a study of hyperlexia
DESCRIPTION
A Study of HyperlexiaTRANSCRIPT
BRAIN AND LANGUAGE 17, l-23 (1982)
A Study of Hyperlexia
JANE M. HEALY
Hathaway Brown School
DOROTHY M. ARAM AND SAMUEL J. HORWITZ
Rainbow Babies and Childrens Hospital and Case Western Reserve University
AND
JANE W. KESSLER
Case Western Reserve University
Twelve children with early intense reading and superior word recognition skills coupled with disordered language and cognitive behavior are described. Cog- nitive, linguistic, and reading measures evidenced a generalized cognitive deficit in forming superordinate schemata which was not specific to visual or auditory modalities. Positive family histories for reading problems were present for 11 of the 12 children, suggesting a relationship between hyperlexia and dyslexia.
INTRODUCTION
Children with remarkably advanced word reading ability despite pro- nounced cognitive and language deficits have been recognized for some time. This unusual developmental disorder, termed hyperlexia by Sil- berberg and Silberberg (1967), was noted in early reports of idiot savants (Parker, 1917; Phillips, 1930), and in case studies of psychotic children (Cain, 1969; Goodman, 1972).
A few recent studies have described circumscribed aspects of the functioning of groups of hyperlexic children. In their initial report on hyperlexia, Silberberg and Silberberg (1967) summarized a group of 28 children whose ability to recognize words was notably higher than either comprehension of material read or overall verbal functioning. Other than
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2 HEALY ET AL.
commenting upon the reading and verbal behavior and reporting that intellectual functioning ranged from “mental defective to bright normal” (IQ’s from nontestable to 126), the authors presented little information about specific aspects of development. More than half of the group had been diagnosed as retarded, autistic, or exhibiting behavior suggestive of neurological impairment.
In subsequent reports Silberberg and Silberberg (1968, 1971) described more fully six of these hyperlexic children. Although a wide variation in perceptual and linguistic skills was reported among subjects, specific findings or testing instruments used to evaluate these skills were not delineated. The authors suggested that difficulty in integrating language was implicit in this condition.
Twelve disordered children who began to read words spontaneously before age 5 were described by Mehegan and Dreifus (1972). Expressive language skills were notably lacking in these youngsters, although oral reading of complex words was proficient. This skill was especially sur- prising since only 2 of the 12 had effective spontaneous speech, mental abilities were well below average, and little comprehension was evi- denced for material read. Disorders of prosody and articulation were common in the group, and the word reading was compulsive in nature. Repetitive physical movements and other behavioral stereotypies were noted.
Huttenlocher and Huttenlocher (1973) studied three hyperlexic children in whom reading developed before age 5 despite language and behavioral disorders. All three were considered intellectually slow and unresponsive to people. Speech was characterized by echolalia, idioglossia, and pro- noun reversals. Piagetian tasks showed that none of the three had attained concrete operations as measured by number and liquid conservation tests. Strengths were found in rote memory and recall of past events, as well as for mathematical problems not requiring a grasp of underlying concepts. Finding that performance was almost identical in response to both oral and written commands, the authors suggested that these chil- dren were able to extract only a limited amount of meaning from verbal material in either auditory or visual modes.
One child described as hyperlexic by Elliott and Needleman (1976) had shown interest in words at 15 months and, although she remained mute, learned to communicate with typewriter and sentence cards. She was also able to match pictures and words, leading these authors to conclude that some comprehension was present. They questioned label- ing hyperlexia as a disorder, seeing it rather as an accellerated cognitive ability.
Most recently Richman and Kitchell (1981) described 10 children who read words at least 2 years above age level, but presented a range of developmental disorders including hyperactivity, language delay, atten-
HYPERLEXIA 3
tional deficits and autistic-like characteristics. Nine of the ten had Full- Range WISC IQ’s within the average range. The authors documented superior visual and auditory memory skills coupled with impaired as- sociative language abilities.
Beyond descriptions of hyperlexic children, numerous theories have been advanced to explain this condition. Explanations have ranged from those holding that the condition represents a difference in degree from normal functioning (Silberberg & Silberberg, 1968, 1971; Rawson, 1971) to those who see it as a manifestation of a qualitative, neurological dysfunction (Mehegan & Dreifus, 1972; Huttenlocker & Huftenlocker, 1973). Others (deHirsch, 1971; Elliot & Needleman, 1976) have suggested that specific gifts in the form of superior skills in word recognition or faculties for remembering words by sight underlie the phenomenon. Rich- man and Kitchell (1981) have postulated that hyperlexia may represent a primary deficit in language association skills. Along with Benton and Pearl (1978) and deHirsch (1971), these investigators suggest that hy- perlexia may be one particular variant of dyslexia. Psychodynamic ex- planations such as those advanced by Cain (1969) or Goodman (1972) have suggested that hyperlexia represents a volitional escape into a non- personal, systematic world.
While most descriptions of such children have emphasized their un- usually early development of word reading, the Richman and Kitchell (1981) study did not report on this aspect of the condition. It designated as hyperlexic children whose word reading was at least two years ad- vanced over expectation. Other than this work, no systematic description of hyperlexics’ cognitive, linguistic, and reading abilities has appeared. Consequently many issues related to hyperlexia remain equivocal. Among those addressed in the present study are the following: Does hyperlexia exist as a syndrome with characteristic features? Are any developmental or familial variables consistently related to the condition? What cognitive, linguistic, and reading patterns exist for these children? Are their abilities specific to auditory or visual input modalities?
METHOD
Subjects Twelve children, eleven boys and one girl, between the ages of 5 and 11 years served
as subjects for this study. These children were drawn from three northern Ohio counties and represented a wide cross section of socioeconomic groups, with parents’ occupations ranging from professionals to welfare clients. Seven were white and five were black. Referrals were obtained from school psychologists, a pediatric neurologist, a language pathologist, and a diagnostic pre-school center. Subjects comprised all children referred during the period of 1 year who met the following criteria: (1) intense early interest in graphic symbols; (2) onset of word recognition prior to age 5; (3) disordered linguistic or cognitive functioning; (4) level of word recognition superior to other linguistic or cognitive abilities.
HEALY ET AL.
Instruments Following subject identification, an extensive parent interview was conducted by the
first author at each child’s home. This interview explored the child’s medical, develop- mental, and reading history, as well as familial learning patterns. Each child was then seen individually for 8 to 10 hours of testing.
The test battery developed for this study explored cognitive, linguistic, and reading competencies. Cognitive and linguistic tests were selected for the mental, rather than the chronological, ages of the subjects, as it was anticipated that they might not be able to perform at chronological age expectations.
To explore the question of modality-specific deficits in these hyperlexic children, alternate written forms of specific auditory subtests were prepared and administered at a testing session after standard administration. Alternate forms consisted of the test questions typed on 3 x 5 cards which the child read. Table 1 summarizes the testing instruments included in this battery.
TABLE 1 SUMMARY OF TESTING INSTRUMENTS
COGNITIVE TASKS McCarthy Scales of Children’s Abilities
Verbal scale Performance scale Quantitative scale
Pictorial memory Word knowledge I Word knowledge II” Verbal memory I” Verbal memory II Verbal fluency Opposite analogies”
Block building Puzzle solving Tapping sequence Draw-a-design Draw-a-child Conceptual grouping
Number questions Numerical memory I Numerical memory II Counting and sorting
Piagetian tasks Detroit Tests of
Learning Aptitude
Object permanence Seriation Number conservation Liquid conservation
Picture absurdities Oral commissions
LANGUAGE TASKS Test of Language Development
Comprehension Meaningful production Repetition
Picture vocabulary” Grammatic understanding”
Oral vocabulary” Grammatic completion’
READING TASKS
Sentence imitation
Wide Range Achievement Test: Reading Goldman Fristoe Woodcook: Reading of Symbols Stanford Diagnostic Reading Test Level B: Comprehension Reading Miscue inventory
u Denotes presentation of both oral and alternate written form of test items.
HYPERLEXIA 5
Cognitive tests selected for use in this study included the McCarthy Scales ofchildren’s Abilities (McCarthy, 1972), Piagetian tasks, and the test of Pictorial Absurdities and Oral Commissions from the Detroit Tests of Learning Aptitude (Baker & Leland, 1959). The McCarthy is a standardized test of mental abilities, similar in construction to the Wechsler Intelligence Scales for Children. It yields a general cognitive index which is derived from tests in three subscales: Verbal, Perceptual-Performance, and Quantitative. Piagetian tasks included object permanence (Uzgiris & Hunt, 197.5) seriation, number and liquid conser- vation. Seriation required the child first to copy a “stairway” of graduated wooden blocks, and then to insert additional blocks into the construction (Elkind, 1968). A number con- servation test with modified verbal requirements (Miller, 1976) was used with chocolate M&M’s serving as the stimulus items. The child was asked, “Which row has more-which would you like to eat?” A standard liquid conservation test was used (Bruner, 1966). Pictorial Absurdities required the child to tell or indicate in some manner the absurdity in each of a series of pictures of common situations, such as a tree bearing several different kinds of fruit, or a child pushing an adult in a baby carriage.
The Oral Commissions subtest from the Detroit Tests of Learning Aptitude was also administered in both oral and written forms, with the two modes alternated in each of two testing sessions. Commissions consisted of eight sets of directions, ranging from one to four parts each, for example: “Walk to the window; then put this book on a chair.”
Language Tests likewise were planned to explore auditory and visual receptive mo- dalities, with verbal and nonverbal response alternatives. Subtests of the Test ofLanguage Development TOLD, (Newcomer & Hammill, 1977), shown in Table 1, tapped syntactic and semantic skills through both picture recognition and expressive language tasks. Again, selected subtests were administered at a subsequent testing session with the stimulus questions typed for the child to read. In Picture Vocabulary and Grammatic Understanding, the child was asked to point to or place the word or sentence he had just read on the appropriate one of four pictures. Oral Vocabulary required a definition of single words (such as “bird” or “old”), while Grammatic Completion tests required completion of a sentence with a syntactically correct word.
Reading Tests included tests both of word recognition and comprehension. The word reading section of the Wide Range Achievement Test WRAT (Jastak & Jastak, 1965), yielded a score for single word recognition, and the Reading of Symbols from the Goldman Fristoe Woodcock Auditory Skills Test Battery GFW (Goldman, F&toe, & Woodcock, 1974) was used to test mastery of phonological principles in nonsense words. The Stanford Diagnostic Reading Test Level B: Comprehension SDRT (Karlsen, Madden, & Gardner, 1976) included both sentence and paragraph meaning. The former required a picture choice response to a single sentence, while the latter involved choosing words to complete related sentences in a modified cloze procedure. In the Reading Miscue Inventory RMI (Goodman & Burke, 1972), the child read a passage in which oral reading errors were tabulated and evaluated. The child then was asked to retell the story as an index of comprehension.
RESULTS
Histories
Historical information obtained from the families supported distinct commonality of development in all twelve subjects (Table 2). While gross motor milestones were normal, patterned actions such as tying shoes, buttoning, zippering, and even opening doors were uniformly delayed. Behavioral problems, particularly those associated with autism, were frequently cited, and all 12 subjects were described as difficult or puzzling
TABL
E 2
SUM
MAR
Y OF
DAT
A FR
OM
FAM
ILY
INTE
RVI
EW (x
= ye
s)
KB
DM
SC
G
T
Age
Se
x R
ace
Dev
elop
men
tal
mile
ston
es
Wal
k (m
onth
s)
Tie
shoe
s (y
ears
) La
te b
owel
con
trol
Beha
vior
Ph
ysic
al s
tere
otvo
ies
Lack
of
inte
rest
-in
Peer
pro
blem
s Sp
eech
his
tory
O
ne w
ord
(yea
rs)
Sent
ence
s (y
ears
) Ec
hola
lia
Spee
ch p
robl
ems
Rea
ding
toys
Age
first
obs
erve
d (y
ears
) W
atch
ed S
esam
e St
reet
Pr
eocc
upie
d w
ith r
eadi
ng
Enjo
yed
bein
g re
ad t
o C
urre
nt s
choo
l pla
cem
ent
Spec
ial
clas
s EM
R
LD
Mai
nstre
amed
R
egul
ar c
lass
H
ande
dnes
s C
hild
M
othe
r Fa
ther
S-6 M
W
12
No X X X 14
4 X 3 X X X X am
R
am
6-5 M
B 11
No X X X X 1”
54
X X 24
X X X am
R
R
SM
CB
KF
DH
B
F C
D
MG
7-l M
W
11
No X X X X 1”
5 X X 3 X X X X R
R
R
7-5 M
W
12
No X X X X 2 41
X X 39
X X X L R
R
7-5 M
W
15
7 X X X X 1 4f
X 21
X X X Rb
R
R
8-2 M
B 10
No X X X 3 4 X X 31
X X Lb
R
am
8-2 M
B 12
No X X 14
2”
X 3 X X X X L R
R
8-9 M
W
12
I X X X 3 4 X X 3 X X X X R
R L
8-10
M
B
9-7 M
W
10-3
M
W
l@
11
13
8 6
10
X X
X
X X X 21
5 X X 21
X X X X Rb
R
R
X X X 3t
6 X X 3f
X X X
10 m
o’
4 X X 3 X X X
X R
R
am
DB
Q
\ 10
-7
F B 12 I X X X 5
E
8 X 5 m
X
cl
4 F
X X X R
R
L
0 St
oppe
d.
D Ex
amin
er
obse
rved
am
bide
xtro
us
hohs
lvin
r
HYPERLEXIA 7
children. Physical stereotypies such as hand flapping, spinning, or rocking were common, and all but one child had shown a notable absence of interest in toys. All had problems relating to peers and were described as inflexible and intent on activities of their own choice. Speech histories showed a common pattern of delay with echolalia often noted. All of these youngsters had been referred to professional services for behavioral anomalies and/or language delay. Most had been classified as retarded by at least one professional. Only one was currently being educated full- time in a regular classroom, although earlier he had special developmental classes.
While all of the mothers were right-handed, two fathers were left- handed and four were ambidextrous. Two of the subjects were clearly left-handed, and two ambidextrous. Four had been reported by the fam- ilies as either right or left-handed, but were observed to use both hands for tasks usually performed by the dominant hand.
In dramatic contrast to other development, reading histories, also shown in Table 2, illustrate unusually precocious acquisition of word reading skills, most commonly noted first around age 3. Each family was uniformly shocked at this development, and none had taught the child to read. Some of these children actually began to read words before they talked meaningfully, demonstrating word recognition by pointing or spell- ing with magnetic letters. All were preoccupied, almost compulsively, with letters and words, and spent hours studying books, labels, and catalogs. In a typical account, one mother described her child as lying in his playpen at age 24, studying books and ignoring his toys. All but two had intently watched Sesame Street. Reading appeared to have replaced other developmentally appropriate activities for all of these children, and most were reported to have continued their fascination with word-reading until the skill was highly developed. Families uni- formly agreed, however, that the children had great difficulty under- standing what they read.
An unexpected pattern that emerged from these interviews was one of reading disorders on the paternal side of 11 out of 12 of these families. Table 3 summarizes data relevant to these findings.
While 9 mothers reported that they enjoyed reading, only 1 father was so described. This is not surprising, since 8 of the 12 fathers had sig- nificant reading problems, and one other, who had dropped out of school in Italy, had never learned to read English. These cases were charac- terized by delayed acquisition of reading, poor comprehension, or adult dyslexia. The fact that several of these men had gone on to finish high school, college, or even a medical degree suggests that intellectual re- tardation was not the primary factor in much of this reading pathology. It is also notable that seven families reported male and female siblings with some form of language-learning disorder, ranging from severe mental
TABL
E 3
SUM
MAR
Y OF
FAM
ILIA
L R
EAD
ING
PRO
BLEM
S
KB
DM
SC
G
T SM
C
B K
F D
H
BG
CD
M
G
DB
Enjo
ys r
eadi
ng
Mot
her
X’
X X
X X
X X
X X
Fath
er
X
Year
s of
sch
ool
Com
plet
ed
ii
Mot
her
12
13
12
6 12
12
12
BA
13
BS
BA
12
Fa
ther
13
12
BA
d.
0.’
11
d.o.
d.
o.
MD
15
BA
M
S 12
5 3
Rea
ding
pro
blem
s M
othe
r X
F Fa
ther
X
X ?”
X
X X
X X
X
Sibl
ings
X
X X
X X
X X
Pate
rnal
rel
ativ
es
X X
X X
X X
? M
ater
nal
rela
tives
X
X
‘x =
Yes.
’
d.o.
Dro
pped
out
of
scho
ol.
’ ?
Info
rmat
ion
not
avai
labl
e.
HYPERLEXIA 9
retardation to documented reading deficits. One older male sibling had been hyperlexic and was now in high-school EMR classes. In two other families, younger brothers had not yet acquired language at age 3, al- though one was reported to be reading words at nursery school.
Test Findings
Table 4 summarizes test scores for all individual subjects in this study. It should be noted that subtest scores on the Test of Language Devel- opment and the Detroit Test of Learning Aptitudes are reported in age level scores, while the three reading tests are scored by grade levels (a typical 7-year-old, for example, would score at grade level 2.0). Ex- amination of this table reveals notable discrepancies between perfor- mance on cognitive and linguistic tests and on the two tests of word recognition ( WRAT and GFW). The SDRT comprehension scores, how- ever, in all but one case, reflect depressed ability even on this picture and single-word measure designed for children in Grade 2.
Tests of Cognitive Abilities: McCarthy Scales
In Table 4 it may be seen that the ratio of mental to chronological age on the total battery ranged from .47 to .91. Table 5 shows a group profile on all McCarthy subtests in z, scores, which are calculated by subtracting the mean score for age from each subject’s score and dividing by the SD in the normative sample for each subtest. Thus, each z score rep- resents a comparison with “normal” functioning: e.g., a score of + 1 is one SD higher than the norm, -2 is two SD lower, etc. The Chart of Extremes in Table 5 shows only those scores outside I-C 1 SD, so a group profile of strengths and weaknesses may be seen. Group mean z scores and SD’s are also reported for each subtest.
Scores reveal relative group strengths on Verbal Fluency, where four children were above one standard deviation and only two were below. In this test, subjects are asked to name as many items in a category, such as food, that they can think of in 20 sec. These items elicited such a rapid series of associations from many of the children that it was necessary to review tapes of each session for accurate scoring.
Relative strength was also found on Numerical Memory I and II (digits forward and backward). Performance on the latter test, however, was variable, as it was on Pictorial Memory.
Although only one child scored below expectation on the Block Build- ing subtest, these constructions are extremely easy for children over 6 years; scores on this subtest probably should not be viewed as repre- senting a particular group strength. Tapping Sequence, a repetition mem- ory task where the child is asked to play a sequence on a toy xylophone after demonstration by the examiner, was also high for the group.
Several subtests were uniformly difficult for most children in this study. Only one child scored within one standard deviation of the mean on
TABL
E 4
SUM
MAR
Y O
F TE
ST R
ESU
LTS:
IND
IVID
UAL
SU
BJEC
TS (A
GE-
GR
ADE
LEVE
L SC
OR
ES)
Subj
ect
CA
McC
arth
y
MA/
CA
Pict
ure
voc.
TOLD
D
TLA
WR
AT
GFW
G
ram
mat
ic
- -
SDR
T O
ral
Und
er-
Sent
ence
G
ram
mat
ic
Pict
ure
Ora
l W
ord
Rdg
. -
voc.
st
andi
ng
Imit.
C
ompl
etio
n Ab
s.
Com
m.
Rec
og.
Sym
b.
Com
p.
Age
Scor
es
Age
Scor
es
Gra
de S
core
s
KB
5-6
DM
6-
5 SC
7-
l G
T 7-
5 SM
7-
5 C
B 8-
2 K
F 8-
2 D
H
8-9
BF
8-10
C
D
9-7
MG
10
-3
DB
10-7
.91
4-9
4-4
4 4
4 <3
4-
9 3.
8 2.
4 1.
8 .4
7 4
4-4
4 4
4 X
” 3-
3 4.
1 4.
1 X
.71
4 4-
4 4
4 4
5 5-
6 7.
1 7.
5 2.
1 .7
5 4-
3 4
4 4
4 <3
5-
6 4.
4 5.
4 1.
9 .8
8 4
4-4
4 S
-11
5-3
3-3
8-O
9.
3 12
.4
2.2
.86
8-6
6-9
7-3
4-9
5-l
5-3
7-6
4.5
3.8
2.5
.86
8 6-
3 5-
6 4
4 5-
o 6-
3 4.
2 4.
3 2.
4 .7
4 8-
3 4-
4 5-
6 4-
4 6-
6 4-
9 6-
9 3.
9 2.
5 3.
1 .7
4 4-
3 5-
7 4-
6 4
4 4-
6 7-
3 8.
7 12
.9
2.3
.68
4-9
4-4
4 4
4 5-
6 6-
9 4.
7 3.
8 2.
0 .7
3 8-
11
7-9
7-3
8-11
7-
5 5-
o 7-
3 11
.3
12.9
2.
7 .6
2 4
4-4
5-9
6-3
4 3-
9 7-
6 4.
8 4.
2 2.
0
a X
= U
nabl
e.
TABL
E 5
SUM
MAR
Y C
HAR
T O
F EX
TREM
E z
SCO
RES
: MC
CAR
THY
SUBT
ESTS
Num
ber
of s
core
s
Subt
est
Verb
al f
luen
cy
Num
er.
mem
. I
Num
er.
mem
. II
Bloc
k bu
ildin
g Ta
ppin
g se
quen
ce
Dra
w-a
-des
ign
Pict
oria
l m
emor
y D
raw
-a-c
hild
O
ppos
ite a
nalo
gies
C
once
ptua
l gr
oupi
ng
Puzz
le s
olvi
ng
Num
ber
ques
tions
Ve
rbal
m
emor
y II
Wor
d kn
owle
dge
Verb
al
mem
ory
I C
ount
ing
and
sorti
ng
Ran
ge
+1.4
to
-3
.6
+1.4
to
-1
.8
+3
to -
2.1
+ .3
to -
7.3
+2.1
to
-2
.1
+ .9
to
-2.7
+1
.3
to -
3.3
+1.1
to
-3
.5
+ .7
to
-3.0
+
.Sto
-2.4
+1
.4
to -
4.8
+ .4
to -
3.3
+ .9
to
-4.6
-
.4 to
-3
.6
+ .9
to -
5.0
+ 3
to
- 14
.5
Gre
ater
Be
twee
n Be
twee
n th
an
+1
-162
-2
-2
&
-3
4 1
4 3
2 3
1 2 3
3 2
1 4 2 4
1 3 6 3 4 1 1
1 1 1 2 2 1 1 4 2 5 2 1
Low
er
Tota
l th
an
-3
belo
w
- 1
Gro
up
mea
n SD
1 I
2 -
.Ol
3 -
.Ol
4 -
39
1 -
.13
3 -
.21
4 -
.46
5 -
.49
5 -
.60
5 -
.91
5 -
1.02
6
-1.2
2 11
-
1.76
8
- 1.
77
10
- 1.
91
8 -2
.05
9 -2
.45
1.58
1.
12
1.54
3
1.28
g
1.23
‘.I
9 F
1.63
x”
1.
29
s
1.18
.8
5 1.
77
.94
1.73
.9
7 1.
82
1.96
12 HEALY ET AL.
Number Questions. While computation was generally accurate, items requiring numerical reasoning were commonly missed.
Other group weaknesses were shown in Verbal Memory I and II. In the former, subjects generally performed well in repeating strings of unrelated words, but were unable to retain meaningful sentences, thus depressing the entire subtest score. Verbal Memory II required the child to tell back a short story which was read to him. All but three of the subjects were unable to retell even the simplest details of the story, although they had given the appearance of attending when it was read.
Word Knowledge was also a common weak area; the only two scores within the normal range were below the mean. Formulating a definition for even a concrete noun was uniformly difficult, although the child often was obviously familiar with the term and referent in question. Responses were almost exclusively associative, tending toward personal sensori- motor experiences (door: “I close”), syntagmatic relationships (bird: “tweet, tweet”), or echolalic associations, often from television. Very few responses earned full credit.
Counting and Sorting produced nine scores lower than one standard deviation below the mean, with seven of these falling outside of three standard deviations. On this subtest, failure to respond correctly to ques- tions involving ordinal numeration accounted in part for these extreme scores, as very few children above age 7 in the normative population missed these items.
Overall difficulty was experienced by all children on subtests which required organization of relationships or patterns for any type of incoming stimuli (Table 6). This difficulty extended not only to items requiring verbal organization, such as in Word Knowledge and Verbal Memory II, but to numerical concepts, as in Number Questions, and manipulative, visual-motor tasks such as Puzzle Solving and Conceptual Grouping.
The Puzzle Solving subtest was particularly notable in this regard. Typically these youngsters worked exclusively by matching small inner details rather than by forming the broad outline of the figure. Although each child could name the picture puzzle before assembly, this task was extraordinarily difficult for many.
Items in Conceptual Grouping required the child to abstract properties of color, shape, and size, mentally and visually organizing plastic blocks to ascertain missing or inappropriately placed members of a set. These tasks were also notably difficult for the children in this study.
In dramatic contrast, subtests requiring repetition memory skills were areas of strength, as has been noted (Table 6). Subtests in the McCarthy requiring these abilities are Pictorial Memory, Tapping Sequence, Verbal Memory I (part I), and Numerical Memory I and II. Although Numerical Memory II requires the child mentally to reorganize a schema to repeat the numbers backward, it was performed by these subjects as a repetition
HYPERLEXIA 13
TABLE 6 SUMMARY: EXTREME 2 SCORES, MCCARTHY SUBTESTS TESTS OF ORGANIZATIONAL
RELATIONSHIPS AND REPETITION MEMORY
Tests requiring organiza- tional relationships
Puzzle solving Word knowledge Number questions Verbal memory II Conceptual grouping
Total
Tests of repetition memory
Pictorial memory Tapping sequence Verbal memory I Numerical memory I Numerical memory II
Total
+1 -1 to -2 -2to-3 -3 1 3 1 2 0 4 5 1 0 3 4 1 0 3 2 3 0 4 1 0 1 17 13 7
3 2 2 1 1 2 1 0 0 1 2 5 4 3 0 0 2 3 1 0
10 11 6 6
x - 1.22 - 1.91 -1.76 -1.77 -1.02
- .49 - .21 -2.05 - .Ol - .09
Note. t = 2.51, p = < .05.
task. In some cases the children were observed to point to imaginary numerals on the table or in the air as if actually reading them back from a visual icon.
The difference between these two groups of scores was analyzed using a one-tailed paired comparison t test. There was a significant difference between the subjects’ scores on the five tests of organizational relation- ships and the five tests of repetition memory (t = 2.51, df = 11, p < .05).
Piagetian Tasks
While the method of administration used in this study corresponds to standard Piagetian test procedures, these results are presented only as general indications of cognitive development because of a lack of quan- tifiable normative data or age-matched controls. All subjects but one passed the test of object permanence; this one failure was attributable to an inability to follow any organized search strategy in a series of successive hidings. Simple seriation was attained by 10 of the children, but when they were required to insert blocks in the “stairway,” complete bafflement was the common response. Even when it was demonstrated that blocks could be pulled apart to insert others, 10 were unable to alter the previous construction.
Five passed the test of number conservation; correct answers were achieved by counting the M&M’s. In several cases children selected the group closest together as having “more,” despite a smaller amount. It
14 HEALY ET AL.
appeared to the examiner that they were responding to the density of the array rather than length or number. No child in the study had attained conservation of liquids; only one (MG) could be led to the correct answer, but he failed the same test 2 weeks later. No child in the study had achieved an age-appropriate level in these Piagetian tasks.
Detroit Tests of Learning Aptitude
Picture Absurdities produced uniformly low performance levels from all subjects, as can be seen by examining age scores in Table 4. Converted into z scores, they ranged from -3.02 to -7.53 with a mean of -5.04 and a SD of 1.58. The inability did not appear to center on verbal expression of the absurdity, as children generally were able to describe adequately what was happening and often picked out and described details in the picture. Rather, they appeared not to evidence compre- hension of the meaning of the situation pictured.
z Scores for auditory administration of items on the Oral Commissions subtest were also low, ranging from - 1.01 to -7.05 with a mean of - 2.62 and a SD of 2.16. The children responded to isolated words, but seemed unable to apprehend relationships of words in the commands. Bizzare responses resulted. When asked to “Put this pencil on the table; then open the door; then fold your hands behind you,” two children attempted to push the pencil under the door, looking baffled when it did not fit. Similar responses were the rule, with complete confusion resulting from an apparent inability to integrate the commands into any meaningful framework. Sequential auditory memory, per se, seemed to be intact, for the children often correctly repeated the commands. Alternate written presentation of test items elicited similar responses and comparable scores as will be seen later.
Tests of Language (TOLD)
Table 4 details individual age scores on TOLD subtests, and Table 7 summarizes group performance in z scores. Language performance was highly discrepant from chronological age, with most subscores falling below one standard deviation from mean for age and none above 1 SD. This test is normed only through age 8-11, so scores for the three oldest subjects were computed against these norms rather than comparable to actual CA at time of testing. Even including these scores, only four subscores in the entire test fell above mean for age; two on Picture Vocabulary and two on Sentence Imitation.
Because of the extreme low scores on many tests, group means must be interpreted with caution. As a group, subjects did best on Picture Vocabulary, Sentence Imitation, and Oral Vocabulary and worst on Grammatic Completion and Grammatic Understanding. It is important to note that Grammatic Understanding is a test with a recognition re-
TABL
E J
SUM
MAR
Y CH
ART O
F EX
TREM
E z S
CO
RES
: TO
LD
SUBT
ESTS
Num
ber
of s
core
s
Subt
est
Ran
ge
Betw
een
-I&
-2
Betw
een
-2
& -3
To
tal
belo
w
-1
Gro
up m
ean
SD
Pict
ure
voca
bula
ry
+ 1.
0 to
-3.
0 1
6 7
- 1.
30
1.37
Se
nten
ce im
itatio
n +
1.0
to
-2.7
5
5 10
-
1.55
.8
J O
ral
voca
bula
ry
- .3
to
-3.0
6
4 10
-1
.58
.J9
Gra
mm
atic
com
plet
ion
- .J
to
-2.1
3
8 11
-1
.85
.92
Gra
mm
atic
un
ders
tand
ing
- .3
to
-3.0
4
7 11
-
1.91
.7
9
TABL
E 8
SUM
MAR
Y C
HAR
T O
F EX
TREM
E z
SCO
RES
: R
EAD
ING
TE
STS
Num
ber
of s
core
s
Test
R
ange
WR
AT:
R
eadi
ng
+4.7
2 to
-
.26
GFW
: R
eadi
ng o
f Sy
mbo
ls
+2.1
to
-
.7
SDR
T: C
ompr
ehen
sion
+
.05
to -
1.0
Betw
een
Betw
een
Gre
ater
th
an
Tota
l ab
ove
+I&
+2
+2
&
+3
+3
+1
Gro
up
mea
n SD
2 2
3 J
+ 1.
76
1.56
4
2 1
7 +
1.05
1.
07
0 0
0 0
- .3
7 .3
4 __
___
____
__
G
16 HEALY ET AL.
sponse of pointing to a picture in response to a spoken sentence; low scores on this subtest would seem to indicate difficulty processing the syntax and meaning of the sentence and/or the picture, rather than re- flecting expressive language difficulties.
Responses on Oral Vocabulary, a test of defining words similar to the McCarthy subtest, resulted in associative responses. Because scoring on this test allows credit to be given for two such responses, many scores were obtained which do not reflect a conceptual definition. The children were frequently fluent in their associations, but responses overall were limited to echolalic associations, to properties, or to sensorimotor con- nections with the word.
Sentence Imitation was characterized by a rote quality. No paraphras- ing of the sentences occurred and frequently meaning was completely changed in the response, even when certain key words were retained.
Grammatic Completion revealed a lack of expressive syntactic struc- tures commonly mastered by children of these ages. Responses to this sentence completion task also showed, in many cases, a lack of under- standing of the semantic intent of the stimulus sentence; words added might be irrelevant or contradictory to intended meaning.
Tests of Reading
Individual scores for reading-related measures in this study are pre- sented in Table 4, and group summary scores in Table 8. These tests produced strikingly different results from other measures. Overall, the children’s response was positive when these tasks were presented; in many cases they seized the materials and began reading out loud before asked to. Attentional problems, although present, were less apparent than with other tasks. Articulation tended to be more precise in oral reading than in speaking, and inflection and phrasing were often more prosodic in the reading condition.
z Scores on the WRAT word recognition subtest ranged from - .26 to +4.72. Seven subjects scored higher than one standard deviation above mean for age, and only one below the mean. In many cases difficult words were sounded out successfully, and syllabic stress was often ac- curate. In other cases, credit could not be given because the child pro- nounced the phonemes correctly, but inflected incorrectly.
Results of the Goldman Fristoe Woodcock Reading of Symbols support these findings. Reading of these nonsense words required use of phon- ological word-attack skills for completely unfamiliar word configurations. Six children scored at greater than one standard deviation above mean for age, and six within -C 1 standard deviation. On the test of reading comprehension, the Stanford Diagnostic Reading Test, all scores fell below mean for age but within one standard deviation.
Oral reading for the Reading Miscue Inventory showed considerable
HYPERLEXIA 17
variation among this group in ability to read prosodically with observation of phrasing and punctuation. While two of the subjects (MG and SM) read fluently and with expression which suggested linguistic anticipation of the text, the others read with varying degrees of prosody. One child (DM) was unable to read text, although he was proficient with word lists, and the youngest subject’s connected speech (KB) was unintelli- gible. While the remaining children successfully pronounced the words of the text in order, intonation and phrasing were frequently absent, and punctuation was often not observed. Nevertheless, a tendency to self- correct errors was apparent, with corrections occurring immediately after the mispronounciation rather than at the end of the phrase. This fact, as well as the finding that the overwhelming majority of errors occurred from close graphic and sound correspondences, suggests that these read- ers are uniquely responsive to the perceptual attributes of the text rather than to the meaning. Most readers reread and self-correct after they reach the end of a phrase, realizing that they are not “making sense”; such was not the case with these children.
Not only was the pattern of self-correction in these children divergent from normal readers, but their number of errors was so limited as to make scoring of the Reading Miscue Inventory questionable. The most striking finding, however, was that not one of these youngsters, having correctly pronounced almost all of the words in the text, could retell, summarize, or even relate any information from the story. Isolated words and phrases were sometimes recalled, and often the title was repeated in response to the question, “What was the story about?” Most fre- quently, responses were unrelated to the textual meaning, and, on at least one occasion, drawn from a story read 1 month earlier. Even the two most fluent readers failed to meaningfully retell or answer questions about the story. It appeared that these children were not struggling with verbal expression, rather that they had not grasped the overall meaning of what they had read. Further discussion of reading test results of these subjects may be found in Healy (1982).
Comparison of Performance in Auditory and Visual Input Modalities
Tables 9 and 10 show results of the statistical analysis of the selected subtests which were administered in both auditory and visual (written) forms. Subtests of the McCarthy and TOLD selected for this treatment were first administered in the auditory mode for standard scoring in the initial test administration. In sessions at least 1 week later, the identical items were presented with the child reading the item from a prepared card. All children could readily read the sentences presented.
Despite a possible training effect and previous suggestions that these children might be more successful with written than with oral material, there were no significant differences or directions in the scores of the
18 HEALY ET AL.
TABLE 9 COMPARISON OF AUDITORY AND VISUAL INPUT MODALITIES ON SUBTESTS ASSESSED BY PAIRED
COMPARISON 1 TEST (TWO-TAILED)
Subtest
Auditory Visual
32 SD x SD t P
Opposite analo- gies (McC)
Oral vocabulary (TOLD)
Grammatic under- standing (TOLD)
Grammatic com- pletion (TOLD)
Oral Commissions
5.8 1.9 5.6 2.5 .54 NS
5.7 3.8 5.6 4.9 .08 NS
11.1 4.8 11.8 4.9 - .83 NS
9.5 7.6 11.3 8.4 -2.80 < .02 12.6 5.1 11.6 4.8 1.73 NS
TABLE 10 COMPARISON OF AUDITORY AND VISUAL INPUT MODALITIES ON SUBTESTS ASSESSED BY
WILCOXIN MATCHED PAIRS SIGNED RANK TEST (TWO-TAILED)
Subtest
Oral vocabulary II (McC) Verbal memory I (McC) Picture vocabulary (TOLD)
No. of No. where Pairs Vis. > Aud. S P
10 7 12.5 NS 8 4 15.5 NS 8 4 16.5 NS
two administrations except on the subtest of Grammatic Completion. The mean score on auditory was higher than on visual in three subtests: Opposite Analogies, Oral Vocabulary (TOLD), and Oral Commissions; the same in two: Verbal Memory I and Picture Vocabulary; and lower on three: Grammatic Understanding, Grammatic Completion, and Oral Vocabulary (McC).
DISCUSSION
Existence of a Syndrome of Hyperlexia
The children’s histories and test results support the existence of a specific and identifiable syndrome of hyperlexia.
Support from Histories
All children presented developmental histories common in the follow- ing respects. All read words before 5 years of age, and most around 34 years. None had been taught to read, although television may have encouraged development of reading for most. The children pursued read-
HYPERLEXIA 19
ing intensely and with a preoccupation which typically substituted for more usual preschool activities. Severely disordered language compre- hension and expression were present for all of these children. Behavioral patterns were similarly disordered, although assuming different forms in different subjects. While autistic characteristics were frequently con- comitant with the syndrome, they did not invariably appear, and degree of severity varied considerably among children. Behavioral patterns com- mon to all these hyperlexic children included a distortion of symbolic play, a desire to focus intently on an activity of the child’s own choice, difficulty in mastery of many appropriate behaviors in both personal and interpersonal situations, and problems with peer relationships. No con- sistent pattern of pre-, peri-, or postnatal events was identified.
Commonality in familial patterns was found in the existence of lan- guage-learning deficits on the paternal side. Eleven out of twelve families reported close paternal relatives with disordered reading development, and the remaining one was unclear because of the father’s early with- drawal from school. Furthermore, one younger male sibling showed early indications of hyperlexia, and one older male sibling had documented hyperlexia. That 11 of the 12 children studied were male, coupled with the paternal history of language learning problems, suggests that the disorder may be genetically transmitted and its expression may be sex- limited. Other investigators have similarly reported a preponderance of males. Richman and Kitchell’s (1981) study included 8 boys and 2 girls, while Mehegan and Dreifuss (1972) reported findings for 11 boys and 1 girl. All three children described by Huttenlocher and Huttenlocher (1973) were boys, although Elliott and Needleman’s (1976) case study concerned a girl. None of these studies, however, investigated familial history for language or reading disorders. Benton and Pearl (1978), deHirsch (1971), and Richman and Kitchell (1981) have speculated that hyperlexia may actually represent a subgroup of dyslexia. The family histories reported in this study provide data supportive of this possible relationship.
Support from Testing Results: Abilities Associated with Hyperlexia
Support for a common profile of abilities was found in cognitive, lin- guistic, and reading tests. Profiles were uniformly divergent from patterns of normal development in each area.
Cognitive abilities. While overall cognitive functioning was well below age norms, relative skills in repetition memory tasks and concrete cate- gorization were apparent in the testing results. Verbal and numerical memory, particularly for nonmeaningful strings, were strengths. Some categorization skills were evidenced by fluent associative naming as on the Verbal Fluency Test of the McCarthy. These children were most successful when organization was determined by the nature of the stim-
20 HEALY ET AL.
ulus and when immediate sensory cues were available. When they were required to create organizational patterns, or to utilize relational or ab- stract thinking, performance faltered. Failure to develop age-appropriate Piagetian operations substantiate their general inability to free themselves from the perceptual constraints of incoming stimuli and is consistent with findings reported by Huttenlocher and Huttenlocher (1973). The fact that this inability extended to nonverbal as well as verbal stimuli suggests that a generalized cognitive deficit may underlie the syndrome of hyperlexia.
Linguistic abilities. Language testing confirmed a pattern of disordered and/or severely delayed development, which would appear to be an invariable concomitant of the syndrome. Syntactic and semantic skills were depressed in all subjects. Performance on tests involving units of language was better than on those requiring conceptual integration of word groups, rules, and relationships.
Relative strengths were found in recognition of Picture Vocabulary for isolated concrete words, and in sensitivity to syntactic structures at a recognition level. This latter ability may be consonant with abilities noted in repetition memory, as these children frequently evidenced an almost rote command of the structure of word groups even when unable to demonstrate comprehension of the given syntactic or semantic relation- ships. Ability to read orally, often with phrasing and expression, was in dramatic contrast to the syntactic structures produced in formulated language. Disordered syntactic and semantic abilities were found in both comprehension and production tasks. While not directly tested, it was also observed that pragmatic functioning of language was similarly dis- ordered. Demonstrated problems with social use of language, both with adults and in peer groups, was reported for all. In sum, these children appeared to have achieved a high degree of phonological and syntactic automaticity in reading and repetition tasks but were severely limited in their ability to understand or generate meaningful language.
Reading abilities. Reading competencies likewise support some dis- tinct commonalities among this group of hyperlexics. All were word- calling at a level considerably in excess of expectation based on cognitive or linguistic functioning. All exhibited comprehension of single words when read, and all who could attend to connected prose evidenced com- prehension of short literal sentences associated with a pictorial stimulus. None, however, evidenced comparable comprehension of units larger than single sentences without picture response alternatives. All had suc- ceeded in generalizing phonological principles, and in integrating auditory and visual, phoneme-grapheme correspondences.
While degrees of fluent oral reading with correction of miscues at a perceptual, and possibly a syntactic level were observed, participation
HYPERLEXIA 21
in meaning was severely depressed when it was necessary for the child to organize textual meaning beyond a concrete single-sentence level.
Important differences in reading abilities were also found among the group. Despite almost identical early histories of reading behavior, the course of development varied among subjects. At the time testing, in fact, two distinct subgroups could be identified on the basis of decoding ability. Seven subjects were extraordinary in their ability to decode both familiar and unfamiliar word forms, while five were only superior in relationship to their other cognitive and linguistic abilities.
Quantifying the parental attitude toward and encouragement of pre- cocious word reading behaviors was not undertaken in this study. Most parents tended to encourage the habit of word reading and looked on it as a positive sign of development in children suspected of retardation. The one mother who had viewed it with alarm, recognizing its abnormal nature, had the only child in the study whose word reading and com- prehension were roughly comparable. The importance of this point is emphasized by the finding that reading had replaced normal preschool play for these children, who evidenced a paucity of cognitive schemata commonly acquired during sensorimotor and preoperational periods from common childhood experiences. The implications here for redirection of children exhibiting early hyperlexic behaviors into enactive activities which increase participation in meaning would appear to be clear.
Auditory versus Visual Modality Strength
Results of this study support Huttenlocher and Huttenlocher’s (1973) findings that hyperlexics’ deficits are not modality-specific. The only task performed significantly better when read was the Grammatic Completion subtest of the TOLD. Reading the stimulus items may have forced greater attention and thus improved the score. Furthermore, as demonstrated on the Reading Miscue Inventory, some of the children did anticipate syntactic structures when reading. Reading with the additional visual clues may have provided more ready access to rotely acquired syntactic skills. The design, necessitated by scoring procedures of subsequent administration of visual to auditory portions of the McCarthy and TOLD tasks, makes conclusions from these subtests very tentative.
The Oral Commissions test, on the other hand, was administered in a parallel-item, crossed design so that subjects responded to both auditory and visual input at the first session, then to the same items with reversed modality at the second. The nonsignificant results from this comparison may be viewed with more assurance. It is notable that, despite focus of attention by means of the visual stimuli, the children did better in the auditory mode. Likewise, while a slightly better mean response on all tests was obtained with nonverbal or motor tasks, none of these differ- ences were significant.
22 HEALY ET AL.
Once more, it would appear that any effort to circumscribe the dis- abilities inherent in hyperlexia in any narrow modality-specific manner would be erroneous. Indications from this study support the view of a generalized cognitive deficit underlying modality-specific processing limitations.
Issues of Definition
The preceding discussion raises questions regarding the precise defi- nition of hyperlexia. Is early reading behavior the hallmark of the con- dition, or must the child continue to word-call at an extraordinary level in order to be so designated? How extraordinary must this word rec- ognition be?
Several investigators have described children less cognitively impaired than the children in the present study. While the 10 studied by Richman and Kitchell (198 1) presented associated language disorders, all achieved Full Scale WISC IQ’s of 92 or above. Further, no mention was made by these investigators of intense, early, untutored onset of reading. Their criteria for identification as hyperlexic followed Silberberg and Silber- berg’s practice of specification of word recognition on the WRAT at least 2 years above expected achievement level. While a continuum in im- pairment may well exist in hyperlexia, basing identification solely upon accelerated word recognition surely would include many normally de- veloping children. Just such definitional confusion exists in the literature. For example, Niensted (1968) identified 26 out of 45 public-school chil- dren as hyperlexic because their word list reading was at least 1 year higher than their silent comprehension. Hypothesizing that overemphasis on teaching of word-calling skills created this condition, she remedied the hyperlexics by in-service teacher training and remedial instruction. Although this study would seem to misinterpret the clinical problem of hyperlexia, it does point up the need for definitional clarification.
We suggest that the term “hyperlexia” be reserved for reference to the syndrome characterized by spontaneous and intense early interest in letters and words which results in the development of extensive word recognition prior to age 5, coupled with significantly disordered language and cognitive development. Children exhibiting early hyperlexic behav- iors may or may not continue to develop phenomenal word-calling abil- ities, although word recognition remains considerably advanced over other cognitive and linguistic abilities.
One final issue of definition concerns the relationship of this syndrome to dyslexia. While not the focus of this paper, it must be noted that disordered symbolic relationships considered to be integral to the dys- lexic condition are also significantly present in hyperlexia. The existence of common familial patterns, moreover, hints at more than a peripheral relationship between these two language learning disorders.
HYPERLEXIA 23
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