-
THE VALENCES OF INFANT TEMPERAMENTAL CHARACTERISTICS
AND THEIR RELATION TO PARENTING STRESS
Trisha Ackland
B.A. (Honours) Simon Fraser University, 1988
THESIS SUBMITTED IN PARTIAL FULFILLMENT OF
THE REQUIREMENTS FOR THE DEGREE OF
MASTER OF ARTS
In the Department
of
Psychology
(c) Trisha Ackland, 1994
SIMON FRASER UNIVERSITY
March 1994
All rights reserved. This work may not be reproduced in whole or in part, by photocopy
or other means, without permission of the author
-
Name:
Degree: -
Approval
Trisha Ackland
Master of Arts
Title of Thesis: The valences of infant temperamental characteristics
and their relation to parenting stress.
Examining Committee:
Chair: Dr. William Turnbull
Date Approved:
Dr. Elinor W. Ames Senior Supervisor
b r . Janef Strayed Supervisor
Dr. Lucy Lb Mare External Examiner
-
PARTIAL COPYRIGHT LICENSE
I hereby grant to Simon Fraser University the right to lend my thesis, project or extended essay (the title of which is shown below) to users of the Simon Fraser
University Library, and to make partial or single copies only for such users or -
in response to a request from the library of any other university, or other educational institution, on its own behalf or for one of its users. I further agree
that permission for multiple copying of this work for scholarly purposes may be
granted by me or the Dean of Graduate Studies. It is understood that copying or publication of this work for financial gain shall not be allowed without my
written permission.
Title of Thesis/Project/Ex-tended Essay
The Valences of Infant Temperamental Characteristics and Their
Relation to Parenting Stress
Author: . - - (signature)
(name)
-
Abstract
The purpose of the present study was to investigate mother-rated infant
temperamental characteristics and their relation to parenting stress. Fifty-two
mothers of children less than 13 months old were asked to complete a series of
questionnaires: a parent-rated infant temperament measure; a measure of
mothers' perceptions of infants' behaviours; and a parenting stress inventory.
Mothers also recorded infant crying and night waking behaviour on an infant
behaviour diary for 5 days. Results indicate that maternal experience with
children did not affect their ratings of infant temperament. Mothers considered
behaviours that theorists consider as indicators of "difficult" temperament to be
neutral rather than negative. The infant behaviour diary was a significant
predictor of parenting stress in the mother, whereas a composite score from the
mother-rated temperament measure did not predict parenting stress. Significant
gender differences were not found on any of the temperament measures;
however, male infants had somewhat longer crying episodes than female infants.
Male infants were rated as less reinforcing to their mothers, and mothers of male
infants rated themselves as less attached to their infants than did mothers of "?
female infants. Results are discussed in terms of how early infant characteristics . A which require more caretaking may act as a risk factor for negative interactions
I
/'
within the family system and possibly contribute to the development of
behavioural problems in later childhood.
iii
-
Acknowledgements
I would like to thank my supervisor, Dr. Elinor Ames for the opportunity to do this
degree and her support throughout it. I would also like to thank Dr. Janet Strayer
for the opportunity to learn from her, and gain insight into developmental
psychopathology by acting as her teaching assistant for many years.
I am indebted to my husband Michael Gaetz, for his support and encouragement
which were unending, and for his confidence in my ability which never seemed to
waver (although mine frequently did). I am thankful for being given the gift of two
tremendously independent, caring and loving children, Taryn and Robert
Ackland. Without their unselfish natures and understanding this thesis would not
have been possible.
I would also like to thank Lianne Fisher and Kim Chisholm for keeping me sane
during the last few months, and for their friendship and help.
Last but not least, I would like to thank all the mothers and their children who
participated in this study. The motivation and desire to assist in the research by
these women was an inspiration.
"Abred"
-
Table of Contents
................................................................................................................. Approval ii ... ................................................................................................................. Abstract 111
............................................................................................... Acknowledgements iv
List of tables ........................................................................................................ vii
General Introduction .............................................................................................. I
I . Theories of Temperament ................................................................................. 4
Towards conceptual aggreement ............................................................. 11
II . Temperament and Childhood Behaviour Disorders ....................................... 14
II I . Methodological Issues in Measurement ........................................................ 19
Psychometric unsoundness of infant measures ................................ 9
Parental personality bias .......................................................................... 9
Parental reporting bias ............................................................................. 20
The concept of difficultness ...................................................................... 21
................................................................................. Interacting variables 24
IV . Objective measure of infant difficulty ............................................................ 31
Behavioural measurement of negative emotionality:
Crying and its correlates ...................................................................................... 34
Infant crying as a social mediator ............................................................. 40
Summary and hypotheses for the present study ....................................... 42
........................................................................................................... V . Met hod 46
................................................................................................... Subjects -46
Procedure and measures .......................................................................... 47
Infant Behaviour Questionnaire ...... ..:.. ........................................... 48
Valence of Infant Behaviour Questionnaire .................................... 49
Parenting Stress Index ................................................................... 50
Infant Behaviour Diary .................................................................... 51 v
-
.......................................................................................................... Results 53
Hypothesis
Hypothesis
Hypothesis
Hypothesis
Hypothesis
Supplementary Analysis ...................................................... 60
.................................................................................................... VI I . Discussion 62
Appendix A: Infant Behaviour Diary .................................................................... 70
Appendix B: Intercorrelations of IBQ and Diary ................................................... 72
References .......................................................................................................... 73
-
List of Tables
Table 1 . Intercorrelations of Infant Diary Measures ............................................ 54
Table 2 . Regression analyses for the PDS ......................................................... 55
Table 3a . Correlation Matrix for Total Sample .................................................... 59
Table 3b . Correlation Matrix for the Male Subjects ............................................. 59
Table 3c . Correlation Matrix for the Female Subjects ......................................... 59
vii
-
General Introduction
Research in the field of developmental psychopathology
emphasizes the importance of considering the interaction and transactions
between individual characteristics of the child and what is loosely called
the environment. Investigation into global concepts of environmental
factors such as the family has moved towards more detailed and specific
studies of the varieties, styles, and dynamics of such factors. Broad
concepts related to within-individual development, such as genetic
contributions, are now being more precisely delineated. As well as
constitutional impact, such variables as sex, temperament, and cognitive
skills are considered relevant transacting individual variables affecting
developmental outcome (Rutter, 1981 ).
A substantial area of investigation has focused on temperament as
a possible mediator in developmental outcome. According to Rutter
(1 982), "temperament constitutes a variable of considerable predictive
power in developmental psychopathology, a power with both practical and
theoretical implications." (p. 14). Rutter (1 989) has postulated several
mechanisms that may be involved in the hypothesized association.
Specific dimensions of temperament may act as a direct vulnerability to
specific psychopathological disorders; may increase susceptibility to
psychosocial adversities; as well as influence the choice of activities and
experiences within the environment. Other mechanisms suggested by
Rutter include transactional factors such as goodness of fit between the
child's temperamental qualities and his or her environment, and, related
-
but distinct, that infants and children bring into social interaction their
temperamental qualities which influence the response they will receive.
"The possibility that to some extent people shape their own environments,
that nature helps to shape nurture, needs to be considered ..." (Rutter,
1989; p. 473).
The main research focus concerning temperament and
psychopathology has been on the issue of whether parentally perceived
infant temperament predicts later psychopathology and/or behaviour
problems. The focus on infancy derives from the common belief that the
link between temperament and manifested behaviour is relatively direct
during infancy but becomes more complex as the child matures
(Goldsmith et al., 1987).
The present thesis commences Chapter 1 with a review of the
dominant theoretical frameworks in which to conceptualize and study
empirically the construct of temperament. The frameworks are diverse
and each carries a uniqueness to the construct. This diversity of defining
characteristics believed to encompass temperament has been suggested
as the greatest obstacle for researchers to overcome (Goldsmith et al.,
1987). There are also however, compelling similarities across the
frameworks in the core defining features of the construct. The review
concludes by providing an operational definition of temperament generally
accepted in the field and the one to be used in the current research. The
rationale for choice of measurement instruments used in the current
research based upon this operational definition is also provided.
-
Chapter 2 reviews the empirical literature examining the
relationship between infant temperament and later behaviour disorders.
Chapter 3 discusses several possible reasons for the lack of sufficient
evidence linking early temperament with later behaviour problems.
Chapter 4 outlines a method of measuring early temperament relatively
independent of maternal perception bias and closes the chapter with the
research hypotheses for the present study.
Chapter 5 outlines the method, Chapter 6 the results and Chapter 7
provides a discussion of the findings of the current study and future
directions for research on temperamental differences in the infancy period.
-
I. Theories of temperament
The term temperament is defined in diverse ways by different
scholars and practitioners in the field of child development, with empirical
research in the area less than 30 years old (Garrison & Earls, 1987).
Basic conceptions and classifications of temperament have their roots in
adult personality research. The functional thinking that applies to internal
regulatory roles of temperament tend to derive from psychophysiology, the
Pavlovian tradition, and the work of Eysenck and Gray (Goldsmith et al.,
1 987; Roth bart, 1 989a).
Early adult personality theorists such as Allport (1 937) and Cattell
(1 950) viewed temperament largely as hereditary characteristics that were
somewhat resistant to environmental influence when compared to those
aspects of personality more determined through experiential factors.
Allport emphasized emotional and mood qualities, while Cattell discussed
temperament in terms of impulsiveness versus reflectivity, or threshold for
excitability.
Developmental research frontiers were broken by Alexander
Thomas and Stella Chess in the early 1960s, with their approach to
temperament emphasizing these personality characteristics as being
displayed in the form of a behavioural style. To these researchers,
temperament is viewed as "a general term referring to the how of
behavior. It differs from ability, which is concerned with the what and how
well of behaving, and from motivation, which accounts for whya person
-
does what he is doing. Temperament by contrast concerns the way in
which an individual behaves" (Thomas & Chess, 1977; p. 9).
Originally Thomas's and Chess's theoretical perspective
emphasized the organismic contribution of genetic and physiological
factors over environmental variables such as early social interaction
(Thomas & Chess, 1957). Incorporating new findings as their longitudinal
research (New York Longitudinal Survey; NYLS) progressed over the
years has resulted in an emphasis on viewing temperament as a
phenomenon largely created through transactions between the child and
the environment, although consideration of organismically originating
characteristics are still present in their work (Chess & Thomas, 1986).
Thomas, Chess and Birch (1 968) constructed a multidimensional
description of early behavioural style from a content analysis of the first
twenty of a total of 136 parental descriptions of infant behaviour from the
NYLS sample. Nine separate dimensions of temperament were derived
from the original analyses: Activity level; Rhythmicity; Approach or
Withdrawal; Adaptability; Threshold of responsiveness; Intensity of
reaction; Quality of mood; Distractibility; and Attention span and
persistence (Thomas, Chess & Birch, 1968).
Further exploration of the data using factor-analysis identified three
general constellations of temperament based upon combinations of more
than one dimension. The largest group (approximately 40%) in their
sample were considered Easy children and displayed a behavioural style
high in rhythmicity, high in adaptability, and moderate in activity, intensity
-
and mood. The second largest group (approximately 15%) of children
were labeled as Slow-To-Warm-up and displayed a behavioural style
combining slower adaptability to new situations with mild intensity and
negative responsivity. About 10% of the sample were categorized as
Difficult. These children displayed a behavioural style consisting of the
dimensions of high negative mood, high withdrawal, high intensity and low
rhythmicity (Chess & Thomas, 1986).
Thomas, Chess and their colleagues have contributed enormously
to the study of early human development, publishing research findings
from the NYLS since the 1960s. These authors are considered pioneers
in the field of individual differences during infancy and early childhood,
generating interest as well as voluminous research over the years.
Consequentially, they have also set the tone of much of the subsequent
work in this area.
Bates, Freeland and Lounsbury (1 979) retain all nine NYLS
dimensions in their Infant Characteristics Questionnaire (ICQ) and add
fussiness, sociability, changeability, and soothability. Bates and his
colleagues have focused their efforts on the temperamental style of fussy-
difficultness which corresponds to the negative mood and high intensity
dimensions in the NYLS framework. Bates (1 987) defines temperament
as dimensions of personality that are basic, early appearing, biologically
rooted and fairly continuous. His framework emphasizes the extent to
which temperament affects social relations and personality development.
Bates (1 980) views temperament to be an inherently interactional
-
phenomenon and defines difficult temperament as " representing an infant
or child's negative emotional responsiveness as perceived by the
individual parent, as well as representing qualities of the child, the parent
and their relationship" (p. 308).
The major criticism of the highly interactional view of temperament
postulated both by Thomas, Chess (1 986) and Bates (Bates et al., 1979;
Bates, 1980; 1987; 1989a) centres on the issue of stability. Plomin (1 982)
agreed that the interaction of child and environment are required for
behaviour, but argued that in understanding individual differences the
important question is the relative extent to which behavioural phenomena
can be explained by individual temperament, by environmental influences,
and by temperament-environmental interactions. In order for the construct
of temperament to be useful in attempting to delineate the heritability and
predictive utility of individual differences, stability is a critical factor. Thus,
Plomin stated "although any measure of temperament includes the
products of former temperament-environment interactions, to measure
temperament as independently as possible of the environment is a
reasonable goal" (Plomin, 1982, p. 39).
Buss and Plomin's (1 975) approach emphasized the heritability and
predictive value of temperament characteristics and derived their definition
directly from theoretical work by Allport (1 937) and Diamond (1 957). To
them, temperament is a set of genetically inherited broad dispositions that
appear early in life and underlie a variety of personality traits (Buss &
Plomin, 1975). These authors presented five criteria to be met when
-
deciding which personality dispositions should be called temperaments.
These criteria include: evidence of a genetic component, stability during
development, presence in adulthood, adaptive qualities, and presence in
other animals. Buss and Plomin identified three dimensions of
temperament: Emotionality, Activity and Sociability. Originally impulsivity
was included but later eliminated after failing to meet the specific criteria
concerning heritability and continuity (Buss & Plomin, 1984). Although the
model stresses the importance of genetic inheritance and stability, Buss
and Plomin (1 975) stated that temperament is expected to differentiate
during development with the course of these inborn dispositions being
determined by interaction with the environment. For example, emotionality
in early infancy is displayed by crying and fussing behaviours
undifferentially, however, with maturation emotionality differentiates into
fearfulness, frustration, and negative responses to specific environmental
situations.
Rothbart (1 989c) argued that concepts of temperament that
emphasize tr,ait-like qualities has led to a focus on the stability of
temperament over time rather than its development. By taking a
developmental perspective, she attempted to describe the structure of
temperament at successive periods of development, to assess the degree
of stability or instability of individual differences in the components of
temperament over time, and to determine the degree to which
temperament at one age may constrain personality and temperament at
the next. Rothbart (1 986) has defined temperament as "constitutionally
-
based individual differences in reactivity and self-regulation, with
"constitutional" referring to the relatively enduring biological makeup of the
individual, influenced over time by heredity, maturation, and experience."
(p. 356). This approach emphasized the psychobiological bases of early
behaviour by examining the reactive aspects of infant behaviour in terms
of physiologic arousal, and the active qualities of self-regulation that serve
to modulate reactivity such as cognition, perception, and affect. Rothbart
(1 989a) suggested that temperament can be behaviourally observed as
individual differences in Emotionality, Activity, and Attention. This
framework of temperament builds upon the basic tenet that temperament
is constitutionally based and therefore measurable via physiologic indices
(Rothbart 1989b).
The inclusion of cognitive factors is in contrast to previous work and
to the view of temperament and cognition as two distinct and pure
constructs (Garrison & Earls, 1987). Support of this new position may be
increased in the near future, however, as current research on cognition
and temperament are discovering a relationship between the two
constructs. Perhaps the main value of Rothbart's perspective is in its
ability to designate psychophysiological parameters to measure child
behaviour. These measures, which will be crucial in developing scientific
credibility for the construct of temperament, are currently being
investigated and validated by a number of researchers. Individual
differences in physiological and anatomical mechanisms regulating
attention (Foote, Bloom, & Aston-Jones, 1983; Posner & Rothbart, 1981 ;
-
Posner & Presti, 1 987; Posner, Inhoff, Freidrich, & Cohen, 1 987; Pribram
& McGuiness, 1975); reactivity (Gray, 1982; Davidson & Fox, 1989;
Masser & Farley, 1989; Tucker & Williamson, 1984); approach to novel
stimuli (Amsel, 1986), mood (Gray, 1982; Panskepp, 1982; Easterbrook,
1959; Murphy & Redmond, 1975); motor activity (Foote et al, 1983; Tucker
& Williamson, 1984); and sociability (Farley & Farley, 1970) have been
indentified. In addition, physiological correlates have also been proposed
for individual differences in cognitive style (Israel, 1969; Zuckerman,
Buchsbaum, & Murphy, 1980; Casal, Caballo, Cueto, & Cubos, 1990:
Eysenck, 1967; Gale, Coles & Blaydon, 1969; Nussbaum, Bigler, Koch, &
Ingram, 1988).
A criticism of Rothbart's framework is that by conceptualizing
temperament so broadly in terms of physiological parameters, it may not
allow the construct of temperament to be operationalized in empirical
research (Goldsmith & Campos, 1982). The definition of temperament
offered by Goldsmith and Campos (1 982) employed measurable
behaviors of individual differences in the probability of expressing the
primary emotions and arousal. They included among the primary
emotions Anger, Fear, Pleasure, and Interest, and measured arousal in
terms of Activity Level. Thus, temperament was considered emotional in
nature, and referred to behavioural tendencies rather than actual
occurrences of emotional behaviour. Cognitive-or perceptual factors were
specifically excluded (Goldsmith et al., 1 987).
-
Kagan, Reznick and Snidman (1 989) did not list a minimal set of
fundamental temperamental dispositions, but suggest that the
predisposition towards behavioural inhibition or disinhibition as a possible
underlying characteristic. Kagan et al., (1 989) treated temperamental
constructs as referring to categories rather than assuming a continuous
dimension, such as sociability or shyness. Initial reaction to unfamiliar
events was reported as a behavioural quality that is moderately stable
over time and independent of social class and intelligence scores.
Related, but not identical, theoretical constructs of introversion-
extraversion have been reported to be among the most stable and
heritable in adult personality work (Kagan, et al., 1989; Eysenck, 1982).
Individual differences in behaviour are associated with peripheral
physiological reactions in the reactivity of limbic structures to novel
situations (Kagan et al., 1989).
Towards conce~tual aareement
In synthesizing the four approaches presented at the Society for
Research in Child Development Roundtable: "What is Temperament?",
(Goldsmith et al., 1987) McCall offered the following definition:
"temperament consists of relatively consistent, basic dispositions inherent
in the person that underlie and modulate the expression of Activity,
Reactivity, Emotionality, and Sociability. Major elements of temperament
are present early in life, and those elements are likely to be strongly
influenced by biological factors. As development proceeds, the
-
expression of temperament becomes more influenced by experience and
context" (p. 524). The inclusion of sociability highlighted the opinion that
temperament was largely expressed within a social context, although
temperament is viewed as a subset of sociability.
Although it is doubtful that one theoretical framework will satisfy all
possible dimensions to be included under the construct of temperament,
Rothbart's psychobiological approach has theoretical and empirical merit.
From a theoretical level, Rothbart's framework is developmental in
orientation allowing an investigation of temperamental continuity and
discontinuity over time and in relation to normative developmental events.
The specification of parameters within the framework provide association
between the behavioural and physiological domains of temperament. By
focusing on individual differences in reactivity and self-regulation, Rothbart
goes beyond a behavioural style advocated by Thomas and Chess, and
specifies individuals' predispositions to particular reactions, including but
not limited to primary emotions as do Goldsmith and Campos (1 982), or
negative emotions as do Buss and Plomin (1 975). In addition, although
Rothbart sees temperament as existing within the person, the framework
is also transactional in nature. The environmental demands influence the
expression of temperament, affect others directly, and require different
caregiving strategies. Temperament influences the choice of
environments in which to participate, and contributes to the development
of cognitive strategies, social skills, and later personality functioning
(Goldsmith et al., 1987).
-
The Infant Behavior Questionnaire (IBQ; Rothbart, 1978) assesses
Activity Level, Smiling (and Laughter), Fearfulness, Distress to Limitations,
Duration of Orienting and Soothability through caregiver report. The IBQ
is free from several methodological problems dominant in other
temperament measures and is recommended by Slabach, Morrow, &
Wachs (1 991) for studies involving infants' normal behaviour patterns. A
full description of the IBQ and its psychometric properties is included in the
Method section.
-
II. Temperament and childhood behaviour disorders
Implicit in the majority of research concerning temperament and
behaviour disorders is the assumption that certain individual
characteristics are perceived by others in the environment as negative or
difficult. This interactional view suggests that the infant who is more
difficult for the caregiver will be at risk for later behaviour problems.
Considering the hypothetical role that temperament is implied to play in
the development of behaviour disorders, there have been relatively few
studies on this issue, especially during infancy.
The New York Longitudinal Study was originally designed to attain
a better understanding of the development of behaviour disorders in
children, with a focus on temperament and on the role it plays in the
etiology and expression of disorder (Thomas, Chess & Birch, 1968). Of
the original 136 subjects who entered the study at approximately three
months, 42 developed behaviour disorders during the first five years of life.
Although this research is commonly cited as supporting a direct link
between infant "difficultness" and later behaviour disorders, this is not
confirmed by the 1968 original work. The hypothesized relationship
between difficult behavioural style and behaviour disorders did not emerge
until four years of age. At one year, only activity level, a temperament
dimension not included in the concept of "difficultness", differentiated
between the clinical and nonclinical sample for later behaviour disorders.
No significant association between behaviour disorders and any
temperament dimension was evident from two years of age, and at three
-
years the only temperament dimension associated with behaviour
disorders was Intensity. Thomas et al. (1 968) concluded from their
analyses that difficult temperament in and of itself did not account for
behavioural problems. More recently, Chess and Thomas (1 986) have
suggested that it is the goodness of fit between the individual child's
temperament and the kind of child management techniques used by
parents which accounts for behavioural problems.
Maziade (1 989) also did not find infant temperamental
"difficultness" predictive of behavior problems at age four and one half.
Maziade, Cote, Bernier, Boutin, and Thiverge (1 989a; 1989b) recruited
infants from the general population who were rated at each extreme end of
temperament. No significant relationship was found between infant
temperament and later behaviour problems, even when the data were
analyzed in terms of extreme difficult temperament scores in infancy.
Similar to the Thomas et al. (1 968) findings, temperament assessed after
four years of age was significantly associated with concurrent behaviour
disorders. However, significant continuity for extreme temperament
scores from infancy to the preschool years was found, particularly in the
boys (Maziade, et al 1 989a; 1 989b).
Wolkind and De Salis (1 982) did report that difficult temperament,
defined as negative mood and irregularity in biological functions at 4
months of age predicted behaviour problems at42 months. Temperament
at four months of age was assessed through an interview with the mother
which incorporated 40 items from an original 70-item self-report
-
questionnaire developed by from the NYLS interviews. Wolkind and De
Salis (1 982) derived cluster scales from a correlation matrix of the 40
individual items. Infants were grouped on this scale according to quartile
position, the two extreme quartiles being kept separate and the two middle
quartiles being combined. When the infants were 42 months of age, the
mothers were interviewed regarding behavioural difficulties measured on
the Behavioural Screening Questionnaire (BSQ; Richman & Graham,
1971). The BSQ consists of 13 items of behaviour difficulties or concern
rated on a scale from 0 (not present) to 2 (severe); a total score of ten and
above on the BSQ is considered indicative of a definite behaviour disorder
(Wolkind & De Salis, 1982). Quartile position on temperament was
significantly associated with the BSQ scores, with the highest quartile
group, called Negative Mood/lrregular receiving higher scores on the BSQ,
although none of the three groups of children had a mean BSQ score
above 10. Of the thirteen behaviour problem items, only "day wetting" was
significantly more prevalent in the Negative Mood/lrregular group.
Management problems were significantly less common in the Good
Mood/Regular group, with no difference between the Middle Quartile
group and the Negative Mood/lrregular group.
Bates and his colleagues (Bates, 1987; Pettit & Bayles, 1984;
Bates, 1989b) reported that 6 month mother rated difficult temperament
predicted later mother rated externalizing (e.g.;aggression) and
internalizing (e.g., anxiety) behaviour problems at 3, 4, and 5 years of age.
By differentiating the type of difficulty, Bates (1 987) reports that 6 month
-
activity management problems are predictive of later externalizing
behaviour problems, and fearfulness at 6 months predicted later
internalizing problems.
Huttunen and Nyman (1 982), in their longitudinal epidemiological
sample of 1,855 found that children who had been rated high on intensity
and negative mood between 6 and 8 months of age were more likely to be
admitted to hospital prior to their fifth birthday for either "acute behavioural
crisis", acute colic spasms, or for "impulsive accidents" which included
contusions, fractures and wounds, while those children being admitted for
pneumonia did not differ on temperamental characteristics.
The measurement of temperament in general, and its predictive
ability in specific, is at present ambiguous. Temperamental qualities,
when measured in toddlerhood or later have been associated with an
increased risk of psychiatric disorder (see Garrison & Earls, 1987; Rutter,
1987; Bates, 1989b). General negative emotionality and negative
reactions to new people and situations show some evidence of predicting
later reports of behaviour problems, especially those seen by the mother
herself. However, results reported in the majority of the reviewed studies
are only of modest size. The few studies that suggest infant temperament
might be related to future behaviour problems are confounded in that the
mother is usually the rater of both temperament and behaviour problems,
which may indicate a personality bias. Furthermore, any association
apparent in the research thus far could be considered a continuity of
-
temperamental characteristics rather than the cause or precursor for
behavioural outcome.
Compelling evidence to support the association between infant
temperament and later behaviour problems is lacking. The endeavor to
detect a linear association between infant characteristics and later
behaviour problems rests on the assumption that early measurement will
best represent those characteristics that are independent of environmental
interaction; an assumption that may be false. Prenatal and perinatal
environmental influences (Rutter, 1989), and maturational differences
(McCall, 1981) have a major impact within the infancy period.
Furthermore, constitutional qualities may not be evident early in life.
Plomin (1 986) states that for most characteristics, the force and stability of
heritability influences increase over time.
-
I I I. Methodological Issues in Measurement
Psvchometric unsoundness of infant measures.
The lack of significant association between infant temperament and
later behaviour disorders could be due to infant measures being
psychometrically unsound. Temperament items in early infancy may not
reflect a reliable picture of the infant, or early scales may not measure
validly those characteristics that are considered to be temperament later in
development. Although individual temperament measures have been
criticized for their psychometric properties, especially those instruments
developed from the NYLS (Slabach et al., 1991), it is unlikely that all
measures suffer from such deficiencies.
Parental personalitv bias
A common criticism levied in the area is that maternal rated
temperament instruments reflect maternal personality rather than child
characteristics. Mothers with severe psychopathology such as
schizophrenia and depression perceived more difficult and fearful
temperaments in their infants, both concurrently (Sameroff, Seifer &
Barocas, 1983) and retrospectively (Silverton, Finello & Mednick, 1983).
This research could be interpreted several ways. It could imply that
maternal reports of infant temperament are merely an assessment of
maternal personality variables. However, equally valid, the association
may imply a genetic component or pre- and perinatal influences on infant
-
constitution. What this research strongly implies is a possible risk to the
infant-caregiver dyad.
Parental re~ortina bias
The lack of concrete association between early infant temperament
and later behaviour disorders may indicate a parental reporting bias,
rather than a parental personality bias. This hypothesis may explain why
temperament, especially at the extreme ends of the distribution, shows
some stability from infancy through school-age but its association with
behaviour problems only strongly emerges during the preschool years or
later. It is conceivable that parental ratings of temperamental
characteristics during early infancy are less variable than those ratings
assessed in toddlerhood and beyond, decreasing the predictability to later
behaviour disorders. Parents may be reluctant to rate the infant as
displaying any extreme characteristics, because of lack of experience with
the infant or unavailability of a reference point to judge behaviour.
Because infants change and develop so rapidly, parental ratings during
early infancy may reflect some form of an averaging bias, whereby
behaviors are accurately rated according to their presence but less
extreme. By the preschool years, parents likely have a more stable and
concrete perception of their child, feel more competent, and have more
experience to incorporate when rating the items. They may thus be more
comfortable in assigning extreme scores.
-
McDevitt (1 986) and Chess and Thomas (1 990) have suggested
that lack of sufficient variance in temperament measures during early
infancy prevents many of the links between early and later behaviour
being detected. Lewis and Starr (1 979) stated that lack of variability or
differentiation of behavioural responses at one point make it extremely
difficult to predict subsequent behaviours. These authors suggest that it is
not until the end of the third year of life that differentiation of behaviour
responses is complete. Although not specific to temperament, these
authors suggests that observed behaviour does not develop response
differentiation until the preschool years.
If continuity is evident in the rank ordering of individual
temperament items over time, and ratings become more variable with age,
early infant temperament may indeed be predictive of later behaviour
problems when the structure of variability is considered.
The concept of difficultness
A further explanation to account for the lack of association between
early temperament and later behaviour problems could relate to changes
across dimensions or scales believed to make up difficult temperament.
When a combination of temperament dimensions are used to reflect a
particular style, e.g., as in the concept of difficultness, stability over time
does not necessarily indicate that each individual dimension remains
stable. Thus, a child could be rated dramatically differently on two scales
from infancy to toddlerhood, but if they were in the opposite direction, the
-
composite score for difficulty might remain the same. For example, a
young infant displaying irregular patterns in sleeping, eating and bowel
movements might be perceived as average; the same infant might also
continually fuss and cry and be rated slightly higher on ratings assessing
negative emotionality. If in toddlerhood, this same child was waking
during the night, hampering toilet training due to unpredictability, and was
still not on a regular eating schedule, parental ratings on Rhythmicity
would be affected negatively. Since crying and fussing behaviors
decrease in frequency and intensity during the toddler years, the child
might no longer be perceived as extreme in mood, especially if there was
a marked decrease from early infancy. A child displaying highly irregular
and unpredictable bodily functions combined with an average mood would
likely receive different reactions from the environment than those received
by a child displaying frequent and intense negative mood combined with
normal regularity, although both children would qualify as having a
"difficult" temperament. Adult characteristics are also stable within the
individual, which may present a problem when characteristics of the child
change over time. Speculatively, a parent may show greater ability to
interact with some aspects of child behaviour than with others, causing the
goodness of fit to shift and create a risk factor for the development of later
behaviour problems.
Therefore, when behavioural styles such as difficultness are
measured it is not clear whether child characteristics do in fact remain
stable over time. It could be maintained that this criticism is unwarranted
-
as the temperamental style remained stable; however, as just described,
different combinations of temperamental dimensions may have more
power than others when the goal is to predict behavioural outcome.
In addition, there is great diversity across and within studies in how
difficultness has been operationally defined, measured and analyzed.
Investigators have analyzed difficultness in terms of a behavioural style
reflecting a composite score from several dimensions of temperament, as
well as only using one dimension. McNeil (1 982) argued "there are
already at least six different constellations of characteristics that have
been suggested to constitute the difficult child concept. When shall we be
able to achieve convergence across different studies if everyone has
different versions?" (p. 152). This lack of specification is likely a major
contributor to the inconsistent results. Several challenges to the concept
of difficult temperament have been put forth on empirical grounds
(Rothbart, 1982). Bates (1 987) reported that several studies using a
variety of temperament questionnaires have found that rhythmicity is not
associated with the cluster proposed to encapsulate temperamental
difficulty. It has also been found that mother's ratings of infant difficultness
are more associated with negative mood than with unadaptability (Bates,
1987). A study by Maziade (1 989) did find however, that mood and
unadaptability scales tended to cluster.
A major issue that has never been addressed is whether the
temperamental dimensions which encompass difficultness are in fact
perceived as negative by the the parent. The notion that individual
-
dimensions of temperament constitute a risk factor for later behavioural
problems implies parental perception of those characteristics to be
negative when they may not be. Furthermore, what is considered to be
negative in one situation or at one age may not be considered negative in
another. Although Bates (1987) has found that parental reports of infant
difficultness center around fussing and crying behaviours, whether these
difficult infant behaviours are considered negative in quality has not been
investigated. It is surprising that there is no evidence on the extent to
which parents find the components of difficult temperament to be negative.
The present research will attempt to remedy this lack.
lnteractina variables
The fact that conclusive evidence for a relationship between early
temperamental characteristics and later behaviour problems is not present
in the literature may indicate not that a relationship does not exist, but
rather, that the relationship is not a direct one. Early infant ratings of
temperament associated with later behavioural problems generally do so
with the introduction of interacting variables such as "goodness of fit"
(Chess & Thomas, 1986). The goodness of fit model suggests that
favorable development occurs when there is a compatability between the
"capactities and characteristics of the individual and the demands and
expectations of the environment" (Chess & Thornas, 1986, p. 12).
Cameron (1 978), reanalyzing the NYLS, data found that difficult
temperament at 1 year predicted childhood behaviour problems at 3 years
-
only when parenting management styles were taken into account, and
only among the female children. Initially, no parental characteristics
differentiated between the difficult and easy temperament groups, but
differences emerged between the parents as the difficult children placed
demands on them. These differences in parental reaction to similar
temperaments determined the development of behaviour disorders
(Thomas, Chess, & Birch, 1 968; Achenbach, 1 974).
Other researchers have attempted to investigate the notion that
difficult infants are the subject of less warm or less responsive interactions
with their mothers. To date, there is little evidence to support this notion,
at least in the infancy period. Bates (1987) in a thorough review of such
studies concluded that mother warmth-responsiveness is not importantly
affected by infant temperament. Daniels, Plomin, and Greenhalgh (1 984)
did not find any relationship between mother rated difficultness and
observed quality of parenting on the HOME scale at 12 or 24 months.
Wachs and Gandour (1 981) also reported no differences in the observed
quality of maternal stimulation to 6-month-old easy or difficult infants.
Findings that do show differences of interaction with more difficult
infants usually occur in "at risk" dyads, such as mothers who are young
and less well educated (Nover, Shore, Timberlake, & Greenspan, 1984),
psychologically disturbed (Campbell, 1979), or hold preexisting attitudes
towards the amount and quality of responsiveness needed by infants in
the early neonatal period that are independent of child temperament
(Crockenberg & Smith, 1982).
-
Other researchers have suggested that infants who are more
difficult to care for affect their mother's physical and psychological health,
and that these changes within mothers lead to risk situations within the
family which may lead to the child developing behavioural problems.
Wolkind and De Salis (1 982) found mothers of 4-month-old infants who
were described as having a negative mood and being irregular in their
biological functioning were more physically tired than other mothers.
Although these mothers were not different on measures of emotional
tiredness or depression at 4 months postpartum, by the time their children
were 42 months old, they were more likely to have developed depression.
Of this group of initially difficult infants with tired mothers who became
depressed, 40% had developed behavioural problems at three and one
half years.
Easterbrooks and Emde (1 984) found that first born, 6-month-old
infants who were more intrusive during a couple-oriented task had
mothers who reported having lower marital satisfaction than those mothers
with less intrusive infants. The intrusive infants were not rated differently
on the IBQ from the non-intrusive infants except for being rated higher on
the temperament dimension of smiling and laughing. The mothers of
these intrusive infants were more likely to respond to them than were their
fathers, who also rated the infants higher on smiling and laughing.
Interpretations of these findings could suggest that the root of socially
demanding behaviour (difficultness) could lie in marital distress, or that
-
possibly the parents diffused their marital tension by redirecting attention
to their child, or by communicating through the child (Bates, 1987).
Other findings suggest that difficult infant behaviour is reacted to
differently by multiparous and primiparous mothers, and may be affected
by the gender of the child. Bates et al. (1 979) found that primiparous
mothers were more likely to rate their infants as difficult, and in fact these
children were observed to exhibit more fussiness than infants of
multiparous mothers. According to Bates et al. (1 979), gender was not a
determinant of whether the mothers perceived the infant as difficult. Dunn
(1 977) also found that primiparous mothers were more likely to let their
infants cry and were less responsive to infant cues. Crockenberg and
Smith (1 982) reported that first born children had mothers who exhibited
more caretaking only behaviors towards them, rather than socially
interactive behaviors.
Wolkind and De Salis (1 982) assessed whether maternal
confidence in parenting affected ratings of temperament. Mothers rated
themselves more at ease and comfortable with their second child than
they did with their first born; however, there were no significant differences
in the temperament ratings of their first and second born children. Bates
et al. (1 979) found no difference between primiparous and multiparous
mothers on their knowledge of developmental milestones; however, the
more knowledge the mother had regarding child-rearing the more likely
she was to rate her infant as easy. Sameroff (1 975) reported that mothers
-
with more children were more likely to rate them as difficult than mothers
with fewer children.
There are numerous studies which indicate that boys show more
behavioural and psychiatric disorders than girls. If temperament is related
to the development of later disorders, and boys are more likely to develop
disorders, gender differences should be evidenced in the research. Most
studies do not find gender differences on temperament dimensions
(McNeil, Persson-Blennow, 1982; Wolkind & De Salis, 1982; Bates et al.,
1979; Crockenberg & Smith, 1982; Fish & Crockenberg, 1981) with the
exception of activity level, where males appear to be more active (Eaton &
Enns, 1986; Hegvik, McDevitt & Carey, 1982; Buss & Plomin, 1984).
However, it has also been found that parents see active infants as more
sociable and more fun (Bates et al., 1979).
Moss (1 967) found that first born female infants who had been
highly irritable at 3 weeks were observed to have more maternal contact (!:
=.68), than were first born irritable male infants (L = .20) observed when
the infants reached three months of age. Moss suggested that male
infants were less consolable; so that their mothers were less reinforced for
interaction; and over time, these mothers showed less responsiveness to
their infant males.
Crockenberg and Smith (1 982) also found that mothers of 3-month-
old infants were less likely to respond to their highly irritable male infants
than their highly irritable female infants. Although these authors reported
no gender differences in actual irritability, the highly irritable female infants
-
were reported as the most alert. Crockenberg and Smith (1 982)
suggested that the greater responsivity to irritable females might be due to
their increased alertness over the male infants, which the mothers might
find rewarding. These authors cited a study by Bell, Weller and Waldrop
(1 971) who reported that irritable male infants displayed reduced social
interest with others as they matured, a possible result of reduced maternal
responsivity.
As indicated by the previous review, and suggested by Thomas
(1 982), even when children display similar temperament, the reactions by
people in the environment may be very different. These differences can
be non-temperamental in nature but related to the birth order, gender,
physical and emotional health of the mother as well as marital satisfaction.
Thus, attention to infant as well as family characteristics should be
considered.
The present research is an effort to address some of the issues
reflected in the research which may account for the lack of significant
predictability of early temperament to later behaviour disorders.
Firstly, as discussed previously, the lack of a significant relationship
between early infant characteristics and later behaviour problems may rest
on aspects of parental perception. A parental reporting bias may exist in
terms of small variability of the temperament dimensions in the infant
period which increases in toddlerhood. This hypothesis can be tested by
examining the extent to which age accounts for the variance in maternal
-
ratings. Secondly, it needs to be asked whether certain temperamental
characteristics are indeed perceived by mothers as negative.
-
IV. Objective measure of Infant Difficulty
Thirdly, it would clearly be advantageous to delineate an early
measure of temperament that is as independent as possible of
environmental interaction, or of maternal bias while remaining practical for
research. A theoretical framework encompassing the manner in which
temperament influences behaviour as well as how it affects the
environment to promote risk for later behaviour disorders must also be
convincing. In addition to a theoretical link, there must be empirical
evidence supporting the relationship.
Although temperament researchers do not always agree on which
behaviors are important, most of the theories have in common a
component that relates to negative emotionality or reactivity (Goldsmith et
al., 1 987; van den Boom, 1989; Bates, 1 989a).
Negative mood is included in two of Thomas and Chess'
dimensions, quality of mood and intensity, both of which are included in
their description of difficultness (Chess & Thomas, 1986). Buss and
Plomin (1 984) consider distress, the tendency to become upset easily and
intensely, to be equivalent to emotionality. Emotionality involves
emotional and behavioural arousal. In terms of temperament, arousal is
the crucial component that yields inherited individual differences. Distress
during infancy should be seen as fear and anger. Early appearing
examples of emotionality are crying, unsoothability, and intense activation
of the sympathetic division of the autonomic nervous system (Goldsmith et
al., 1987).
-
Negative emotionality is included in Rothbart and Derryberry's
(1 981) temperament construct of reactivity which refers to the excitability,
responsivity, or arousability of the behavioural and physiological systems
of the organism. Negative emotionality is approached in terms of the
duration or intensity of stimulation which can be endured before a distress
threshold is reached. lnfants differ in the levels of stimulation or arousal
that they can experience before distress is elicited. Once such a threshold
is attained, some infants rise gradually toward their peak of distress, while
other infants may move rapidly to the level of intense crying (Rothbart,
1989a). lnfants also differ in the peak to which their distress reactions
rise: some infants seldom move beyond moderate fussiness, while others
build all the way to hard, harsh wailing.
Kagan et al. (1989), in their behavioural inhibition approach to
temperament suggest that the biological bases for differences in inhibition,
if present in the first few months of life, would be reflected in extreme
distress to frustration, extreme irritability, poor quality of sleep, chronic
constipation, and other symptoms reflecting high arousal in the central
nervous system circuits involving the hypothalamus, pituitary, adrenal,
reticular activating system, and the sympathetic arm of the autonomic
nervous system.
Bates (1 980) identified through factor analysis, frequent and intense
fussing and crying to be the major temperamental component related to
parental perceptions of the level of difficulty the infant would present to the
average caregiver. To Bates (1 980) negative emotionality is the central
-
feature of difficultness. Bates et al. (1979) found significant correlations
between mother and father ratings of difficultness; between mother and
father ratings of difficultness and observer ratings for difficultness; and
between mother rated difficultness and two home observation factors of
fussiness and unsoothability.
Further information on the objective component of irritability is also
available. Highly irritable infants' cries have a different quality to them
than do those of non-irritable infants. Spectrographs of difficult infants'
cries have shown longer pauses between cry sounds and higher pitched
sounds than cries of temperamentally easy infants (Bates et al., 1979).
Further research on spectrographs revealed that the difficult infants cries
were rated as more 'psychologically demanding' by independent raters
(Lounsbury & Bates, 1982).
Therefore, the most viable temperament theories to date
demonstrate a universal inclusion of negative emotionality as a
temperamental dimension. Research has shown that this dimension of
temperament contributes importantly to perceptions of infant difficultness.
As emotionality is one of only two, the other being activity level,
consensual dimensions of temperament delineated by the dominant
approaches in the field there is validity in its investigation.
-
Behavioural Measurement of Negative Emotionality:
Crying and its Correlates
Negative emotionality or reactivity during infancy is largely
characterized by general irritability marked by fussiness and crying
behaviors. Support for a biological hypothesis can be found in the
consistent diurnal pattern of both excessively and normally crying infants;
that is, most crying episodes occur during the evening hours (Bernal,
1973; Brazelton, 1962). Early infant crying also shows a similar
developmental course over time. Rebelsky and Black (1 972) found that
amount of crying increased from one to six weeks of age, where it peaked
and then declined to 13 weeks. Brazelton (1 962) also found that total
crying per day increased from birth to a peak median of 2.75 hours per
day at six weeks and declined thereafter.
Individual stability of crying has been demonstrated by Korner,
Hutchinson, Koperksi, Kraemer, and Schneider (1 981). Crying was
monitored on 72 healthy full term infants during the first three postnatal
days. Results showed high stability across the three days on percentage
of total crying time. Rebelsky and Black (1 972) reported stability in the
amount of crying from one to 13 weeks of age. Variability within each
infant was high, but it was lower than the variation between infants,
suggesting some individual consistency over the three month period of
study. Fish and Crockenberg (1 981) also found-the frequency of fussing
and crying to be consistent across time and within individual when 16
infants were assessed with the Neonatal Behavior Assessment Scale
-
(BNAS; Brazelton, 1973) in their homes between five and 10 days of age,
and observed in their homes interacting with their mothers at one, three
and nine months. Ackland (1 988) found crying time per day, averaged
over five and seven day infant diaries, to be significantly correlated from
six weeks, to six months and to 14 to 22 months. Snow, Jacklin and
Maccoby (1 980) found the frequency of crying episodes to be reasonably
stable over time in individual children from 3 to 26 months, with crying at 9
months significantly predicting crying at 12, 18, and 26 months.
The trend in thinking about early infant crying is related to
neurological explanations and the biobehavioural shift of the central
nervous system that occurs between 3 and 12 weeks of age, the peak of
crying in young infants. Emde, Gaensbauer and Harmon (1 976) cite
evidence for this shift from the fields of learning, perception, emotionality,
psychophysiology, and neurology. Towards the end of the fourth month
increases in orienting, smiling and laughter occur, corresponding to the
development of the 'stimulus-barrier shift' which decreases infants' distress
to overstimulation (Goldsmith et al., 1987). Rothbart (Goldsmith et al.,
1987) reported lack of stability in questionnaire measures of irritability from
this period to one year and suggested that this was due to a possible
transition in susceptibility to distress after three months.
There is a suggestion in the literature that excessive crying during
the early period is related to other indicators of central nervous system
functioning, such as sleep and activity. Sleep shows marked changes in
early infancy, with active REM sleep declining and quiet sleep increasing.
-
Newborns' sleep in general is controlled by the brainstem. During
postnatal development these brainstem mechanisms come progressively
under the control of the higher level forebrain mechanisms, resulting in
more quiet and less active sleep (Ackland, 1988).
Bernal (1 973) found that 31 O/O of infants in her sample of 14 month
olds were night wakers, defined as waking between 10 p.m. and 5 a.m.
regularly. Total crying time and frequency of crying episodes recorded
during the first ten days of life in the 14-month-old group who were night
wakers, were significantly higher than in those who were not. The night
wakers slept significantly less than did non-wakers both during the first ten
days and at 14 months. The relationship between frequent night waking at
14 months and three years was also significant.
Ackland (1 988), following infants from 6-8 weeks to two years,
found support for the relationship between crying and other biological
correlates. Crying at 6-8 weeks was negatively related to concurrent total
sleep time. By seven months of age crying was no longer
contemporaneously related to total sleep time but showed a strong
positive relationship to contemporaneous night waking episodes. This
relationship was also evident in the 14-22 month group, where increased
night waking was more strongly related to contemporaneous crying than to
total sleep time. Paret (1 983) also reported that those children considered
night wakers, had similar total sleep time to those who slept well, when
measured with a videocamera. Ackland (1 988) and Paret (1 983)
concluded that by later infancy and toddlerhood, total sleep time is
-
compensated for by parental management techniques such as increasing
the number of naps, while early total sleep time reflects less environmental
interaction. Night waking showed significant stability across the three time
periods and was related to early infant crying. In fact, the best predictor
for 14-22 month night waking was crying at six weeks and seven months
(Ackland, 1988).
Several researchers have reported increased motoric activity during
crying episodes as well as retrospective reports of extreme infant irritability
in children later diagnosed hyperactive (Werry, Weiss & Douglas, 1964).
Activity levels appear to be stable over time and have been associated
with sleep problems in childhood. Stability in activity level has been
reported. Korner, Zeanah, Linden, Berkowitz, Kraemer and Agras (1985)
found that neonatal movements measured by a transducer mattress
predicted later activity. Those infants who showed more vigorous activity
in the newborn period tended to become highly active children at four to
eight years, measured by an activity monitor. Battle and Lacey (1 972) in
following up 74 subjects who had been included in the Fels Longitudinal
Study since birth found that activity level could be predicted from previous
age periods. Children who were overly active in the preschool period had
been more active in infancy. Preschool activity level also was related to a
more active behavioural style in adolescence. Fish and Crockenberg
(1 981) assessed newborns with the Brazelton Neonatal Assessment Scale
and found newborn characteristics of motor maturity strongly correlated to
motor activity at nine months of age.
-
In support of the relationship between crying and activity, Brazelton
(1 985) stated that "active, intensely driving babies were likely to have long
periods of crying, which rapidly built up with more and more activity,
startles, and these upset the babies and caused even more crying. High
motor activity, poor consolability, and rapid change of state were
predictable characteristics in the newborn to an intense, unreachable
crying period at the end of each day in the first three month" (p. 331 -332.)
Korner et al. (1 985) studied the activity patterns and characteristic
levels of energy output during the first 3 days of life with an electric activity
monitor that distinguished activity during periods of crying from periods of
non-crying. Crying and non-crying activity were significantly correlated
over the three days, suggesting that the infants tended to be either active
or inactive independent of crying. The researchers made the observation
that non-crying activity was the only reliable measure of activity level
because total activity was so strongly influenced by individual differences
in crying behaviors.
McKeen (1 988) asked parents of 46 infants aged six months to
complete a diary record of their children's crying and sleep behaviors while
the children's activity was independently monitored with actometers.
Parents also completed the Infant Behavior Questionnaire (IBQ; Rothbart,
1978) prior to the recording. Diary measures of crying were significantly
related to the actometer measures of activity, aswell as with the activity
scale on the IBQ. The activity scale on the IBQ and the actometer
measures were also significantly correlated.
-
Gotowiec (1 987) provided support for the proposal that excessive
crying is related to the organization of the infants' nervous system. In his
study neurological organization was operationalized as behaviourally
defined state, the argument being that the organization of state
parameters reflects the underlying functioning and organization of the
neurological systems. Six-to-eight-week-old infants were videotaped while
lying in a crib, and rated every ten seconds for behavioural state. The
results showed that infants who cried more during observation spent more
time in active states even when not crying.
The first prospective study on the relationship between early crying
and later activity was reported by Ackland (1 988; Ackland & Ames, 1990).
Mothers completed diary records of crying at six to eight weeks, seven
months and between 14-22 months. The Toddler Behavior Assessment
Questionnaire (TBAQ; Goldsmith, 1987) was also completed at 14-22
months. Significant correlations were found between concurrent
measures of crying and the activity scale on the TBAQ. Further analysis
revealed that infant crying at six to eight weeks accounted for 37% of the
variance in activity ratings at 14-22 months (Ackland & Ames, 1990).
Negative emotionality defined as crying behaviour illustrates a
stable individual difference present and measurable early in life. It is
related to other neurological factors, that are also dimensions of
temperament, such as irregularity in biological functioning and activity
level. In support of Rothbart and Derryberry's (1 981) temperament of
reactivity, Elliot, Fisher, and Ames (1 988) reported excessively crying
-
infants reached a peak of crying more rapidly than non-excessive criers.
Brazelton (1 985) also reported that excessive criers had more rapid build
up to full cry, changed states more frequently and were less consolable.
Thus, early crying may reflect the neurological organization of the infant
reasonably independent from environmental influences and illustrate
temperamental differences.
Infant crvina as a social mediator
Parents of excessively crying infants have reported less
effectiveness in soothing them when they are distressed (Ames, Khazaie,
Gavel, & Farrell, 1987). Empirical evidence would also suggest that
excessive criers are unsoothable in general and not just in response to
parental method of soothing (Elliott, Fisher, & Ames, 1988). Maternal
reports of ability to terminate crying indicate that mothers are not only less
effective with more irritable infants, but also that more varied techniques
are used (Ames et at., 1987). Excessive infant crying has also been
shown to contribute to increased parenting stress in first time parents.
MacWilliam, Ames, and Mason (in press) have shown that early infant
crying is related to maternal levels of anxiety. Irritability has also been
shown to influence the quality of mother-infant interaction negatively
(Crockenberg & Acredolo, 1 983).
van den Boom (1 989) found that irritability-measured in the
newborn period by the BNAS was related to a developmental pattern of
change in interaction within the infant-mother dyad. Irritable infants were
-
rated as more difficult at 6 and 12 months of age, which was associated
with mothers gradually refraining from involvement with their infant. In
home observations over a period of one year, mothers of irritable infants
tended to ignore crying for part of the time it occurred as well as used
more distance soothing strategies. van den Boom (1 989) reported that
newborn irritability was predictive of an insecure attachment style at one
year.
The mechanism for infant irritability acting as a risk factor for
interactional problems was described by van den Boom (1 989). She
suggested that the more irritable infants will use distress signals such as
crying or fussing to bring their mother into proximity, while less irritable
infants will use positive signals such as smiling. The interaction of these
infant behaviours and maternal response can be seen as a positive
feedback in the case of positive signals (Bowlby, 1969), and negative
feedback in the case of distress signals (Bischof, 1975; cited in van den
Boom, 1989). For example, non-irritable infants will be more likely to use
positive behaviours such as smiling or vocalizations to gain proximity.
These infants will be more effective in not only having their caregiver
respond, but because the intensity of the infant behaviours will likely
increase with proximity to the caregiver, non-irritable infants are more
likely to have his or her mother continue to be responsive until the infant's
needs are met (van den Boom, 1989).
An infant who uses distress signals such as crying will be less
effective in getting and maintaining contact with the caregiver. Distress
-
signals decrease with proximity; thus when the mother responds, the
infant will decrease his or her distress behaviours, and because there is a
reduction in distress, the mother may stop responding before the infant's
needs have been met (van den Boom, 1989). If the infant's needs have
not been met, distress signals will re-occur. Because the mother
perceives herself as unsuccessful in stopping the negative behaviour, she
may attempt to soothe the infant by means other than maintaining physical
contact, such as talking to or distracting the infant with toys. Eventually
the mother may become unresponsive.
A similar framework describing dyadic interaction at risk is provided
by Patterson (1 982). He suggests that if there is a high need for
stimulation in the infant, controlled by fussing and crying to receive
attention, parents may be less inclined to attend to the child when he or
she is not fussing. The coercive pattern in child-mother interaction found
in acting out and aggressive children may have its roots in early infant
crying behaviours.
Summarv and hv~otheses for the gresent studv
Although there is evidence for the continuity of temperament from
infancy to later years, the association between temperament and
behaviour disorders is most clearly detected after ages three or four. The
failure of early infant temperament to predict later behaviour problems may
be due to several reasons: insufficient variability in temperament ratings
in early infancy; behaviours that are theoretically believed to be difficult for
-
parents, but perhaps are not; temperament rating scales that are not
objective enough to tap individual differences; and the mediation of the
association between temperament and behaviour problems by gender,
birth order, or factors within the mother or the family system. Based on
the previously reviewed literature the following hypotheses are made:
1. Increased maternal experience (measured as age or birth order status
of the child) will result in increased variability in ratings on the Infant
Behavior Questionnaire (IBQ: Rothbart, 1978). It is reasoned that parents
may be reluctant to rate their infant as displaying any extreme
characteristics during early infancy, because of lack of experience with the
infant or unavailability of a reference point to judge behaviour. With
increased age of the child, parents may be more likely to assign extreme
scores. Furthermore, multiparous mothers will be more variable in their
ratings than primiparous mothers due to the availability of a reference
point.
2. Mothers will not rate those dimensions of temperament which are
theoretically postulated to encompass "difficulty" as significantly negative.
It is hypothesized that those dimensions reflecting negative emotionality
(distress to limitations and fearfulness) will be rated as neutral behaviours.
It is reasoned that during the first year of life parents are more tolerant of
difficult behaviours, and since the infant is not faced with the demands of
-
social and family rules to a large degree, the expression of "difficult"
behaviours will not be considered to be negative in valence.
3. An objective measure of difficult infant behaviour (Infant Behaviour
Diary) will be more highly associated with overall parenting stress than will
a mother rated temperament measure (IBQ). This hypothesis suggests
that infant behaviour requiring increased parenting (crying, fussing, and
night waking behaviours) will be a better predictor for parenting stress
(measured as the score on the Parent Domain Scale of the PSI) than will
difficult behaviour rated on a temperament scale. It is suggested that
"difficult" behaviours in the first year of life will not have a negative impact
on the mother; rather, those behaviours which demand increased
parenting resources will have a negative impact of the mother.
4. Mothers are hypothesized to rate themselves as having a less positive
relationship with their male infants than their female infants, but male and
female infants will not differ on measures of temperament. This
hypothesis is included to confirm previous research which has shown that
mothers find their male infants to be less reinforcing, and are less
responsive to them.
5. Multiparous mothers are hypothesized to receive higher scores than
primiparous mothers on parenting stress, but their infants will not differ on
measures of temperament. This final hypothesis is included to lend
-
validity to the notion that temperament is a within-individual construct
rather than a within-dyad phenomenon. It had been reported that
psychologically disturbed mothers were more likely to rate their infants as
difficult. If temperament is a within-individual construct, multiparous
mothers who should experience increased parenting stress due to caring
for more than one child, should not rate their infants differently from
mothers with fewer children.
-
V. Method
Subiects
52 mother-infant dyads were included in the present study. All
infants were reportedly full-term and weighed more than 2500 grams at
birth, with a mean birth weight of 3575 grams (range = 2510 - 4564
grams). The ages of the infants ranged from 58 to 385 days, with a mean
age of 202 days (sd = 98). Mothers were represented in all income levels,
reporting annual family incomes from below $20,000 to over $90,000 (M = between $50,000 and $60,000). All except one mother were married or
currently living with the child's father. Thirteen percent of the mothers
reported current full-time employment outside the house, 2% reported their
full-time employment as within the household, 23% were employed part-
time, and 62% reported being 'on leave' from employment, with the
intention of returning to work within the next six months. The mean age of
the mothers was 32 years (range = 23 - 42), and their mean education
level was 15 years (range = 9 - 24 years). Of the total sample of 52 infants, 33 were male and 19 female.
There were no significant differences between the ages of the infant males
(M = 196 days, sd = 94) and females (M = 21 2, sd = 105), f(51) = -.56, e < .57), or their birth order (f(51) = -.04, Q < .96). Of the twenty-three first
born infants, 11 were male. First born children were not significantly
different in age from later born children (f(51) = .49, Q < .62).
Due to insufficient or incorrectly completed data on some
measures, the number of subjects used for analyses ranged from 46 on
-
the Parenting Stress lndex to 52 on the lnfant Behavior Questionnaire.
The number of subjects and degrees of freedom were adjusted for each
statistical analysis.
Procedure and Measures
Mothers in the present study received a letter in the hospital when
their infant was born describing current research activities at Simon Fraser
University. If the parents were interested in having their infant participate
in the research they were instructed to mail an attached card to the
Infancy Research Group at the university. Each of a total sample of 70
mothers was contacted by telephone, informed about the current research
and asked to participate. Upon acceptance by the mother, a package
containing the lnfant Behavior Questionnaire (IBQ; Rothbart, 1978) in its
original form; the IBQ in a modified form inquiring about the valence of
each behaviour; the Parenting Stress lndex (PSI; Abidin, 1990); an lnfant
Behaviour Diary; and a demographic questionnaire was mailed out in a
stamped self-addressed envelope for return. Of the 70 mothers
contacted, 4 refused, 8 could not be included due to prematurity or to the
infant being small for weight at birth, and 6 did not return the research
package. Upon completion of the study, mothers were mailed the results
of the research and an lnfant Scientist Award to thank them for their
participation.
-
Infant Behavior Questionnaire. The Infant Behavior Questionnaire (IBQ;
Rothbart, 1978) assesses temperamental dimensions of Activity Level,
Smiling and Laughter, Fear, Distress to Limitations, Soothability, and
Duration of Orienting through caregiver report. It was designed for 3- to
12-month-old children, and item analyses were performed separately for
463 infants 3, 6, 9, and 12 months of age. To decrease the possibility of
reporting biases, parents are asked about the relative frequency of
occurrence of concrete behaviours in carefully defined situations within the
past week, or, for some items, within the past two weeks. This procedure
reduces the biases which operate most strongly when judgements are
retrospective, global, or involve comparing one's own child to others
(Goldsmith & Rothbart, 1991). The temperament scales were designed to
avoid any conceptual overlap of operational definitions. Items are scored
on a scale from 1 (never) through 4 (about half the time) to 7 (always), or
as X (does not apply: the situation did not occur in the period covered).
Internal reliabilities for the scales, estimated by coefficient alpha,
range from .67 to .85, with a median value of .80. Moderate levels of
agreement between two judges within a two week period have been
reported (1's ranging from .45 to .69, mean 1 = 57, N = 22). All
correlations were significant at Q < .05 (Goldsmith & Rothbart, 1991).
Stability correlations for the IBQ scales range from .23 to 5 8 (mean
1 = .38) between 3 and 6 months; .43 to .67 (mean 1 = 56) between 6 and
9 months, and .29 to .72 (mean 1 = .60) from 9 months to one year. The
data show a general trend for stability to be higher over shorter periods of
-
time and to increase as the infant matures (Goldsmith & Rothbart, 1991).
Correlations range from .15 to .55 (mean !: = .35) from 3 to 9 months, from
.34 to .72 (mean I = .51) from 6 to 12 months; and from .06 to .57 (mean !:
= .31) from 3 months to one year.
Convergent validation of the IBQ and home observations has been
provided by Rothbart (1 986). Product-moment correlations between
Activity, Distress to Limitations, Fear, and Smiling and Laughing converge
with corresponding observationally based behavioural categories at 3
months (mean 1 = .25), at 6 months (mean = .20) and at 9 months (mean
1 = .33). An example from the activity scale is: When put into the bath
water, how often did the baby splash or kick?.
Valence of Infant Behaviour Questionnaire. In the present study, each
item on the IBQ was also rated by the mother on a scale of 1 (a very
positive behaviour) to 7 (a very negative behaviour). Each temperament
scale was summed and averaged over those completed items to provide a
measure of which areas of infant behaviour were viewed as the most
negative. Instructions given to the mother were: "Please rate the
following questions on the scale below indicating how you would perceive
the behaviours IF your baby displayed them (whether or not your baby
actually behaves in this way)". An example item would be: IF your baby,
when put into the bath water splashed and kicked?".
-
Parenting Stress Index. The Parenting Stress Index (PSI; Abidin, 1990) is
a screening and diagnostic assessment technique designed to yield a
measure of the relative magnitude of stress in the parent-child system.
There are three sources of stress as identified by this measure: stress
from the child, stress from the parent, and stress from external life
circumstances. The first source, the child domain (six subscales), consists
of Distractability/Hyperactivity, Demandingness, Mood, Adaptability,
Reinforcement to Parent, and A