effectiveness of dynamic cognitive intervention in … for correspondence: n hadas-lidor, department...

Clinical Rehabilitation 2001; 15: 349–359

© Arnold 2001 0269–2155(01)CR419OA

Address for correspondence: N Hadas-Lidor, Departmentof Occupational Therapy, Faculty of Medicine, Tel AvivUniversity, Tel Aviv, Israel.

Effectiveness of dynamic cognitive intervention inrehabilitation of clients with schizophreniaN Hadas-Lidor Department of Occupational Therapy, Tel Aviv University, Tel Aviv, N Katz School of OccupationalTherapy, Hebrew University Jerusalem, Jerusalem, S Tyano Geha Psychiatric Hospital, Petah-Tiqva and A WeizmanGeha Psychiatric Hospital, Petah-Tiqva and Felsenstein Medical Research Center, Beilinson Campus, Petah-Tiqva, Israel

Received 1st September 2000; returned for revisions 23rd January 2001; revised manuscript accepted 16th March2001.

Objective: To examine the efficacy of dynamic cognitive treatment inrehabilitation of schizophrenic clients.Subjects: Fifty-eight schizophrenic clients that were matched equally into twogroups: a study group (n = 29) (treated by Instrumental Enrichment) and acontrol group (treated with traditional occupational therapy methods).Setting: The subjects were treated in a day rehabilitation centre in thecommunity.Study design: The programme lasted one year, the same schedule wasprovided for both groups. Subjects were randomly assigned and assessedbefore and after intervention with the same battery and at a follow-up sixmonths later, work and residence status were evaluated.Main outcome measures: Instruments included: (1) memory and thoughtprocesses, measured by a battery of structured tests from the LearningPotential Assessment Device (LPAD), Raven Progressive Matrices and GeneralAptitude Test Battery (GATB); (2) functional outcomes, instrumental activitiesof daily living (IADL), measured by a questionnaire; work and residence status;(3) self-concept measured with Fitts questionnaire. Results: Results showed significant differences between the groups onalmost all the cognitive tests (MANOVA revealed significant differencesbetween the two groups for both memory and thought process(F(2.52) = 13.75, p < 0.001; and F(1.46) = 7.28, p < 0.001, respectively) as wellas in work (χ2 = 14.30, p < 0.001), and residence (χ2 = 3.86, p < 0.05) status.There were no significant differences in IADL questionnaire or the self-concept scale. Conclusions: The successful outcome points to the importance of includinglong-term cognitive intervention in rehabilitation of schizophrenic clients. Thiswork suggests that the classic view of schizophrenia as a progressiveirreversible decline that cannot be altered may be wrong.

Introduction

As Green et al.1 state ‘there has been a surge ofinterest in the functional consequences of neuro-cognitive deficits’ (p.119). However, only fewresearch studies dealing with the use and impactof cognitive intervention approaches applied toclients with schizophrenia have been reported.2–5

Green et al.,1 in their second updated review inthe last five years about the associations of neuro-cognitive deficits and functional outcomes inschizophrenia, found that published studies havedoubled. The new review confirms their originalfindings that significant relationships existbetween cognitive deficits and various areas offunctional outcomes. However, they further askthe important question how neurocognition isrelated to function, suggesting that one of theexplaining variables may be ‘learning potential’assessed dynamically. The present study usesFeuerstein’s Dynamic Cognitive approach6,7 asthe basis for intervention and assessment, thuscontributing a first account of learning potentialof schizophrenic individuals.

A different review prepared recently for theCochrane Library8,9 regarding the impact of cog-nitive rehabilitation (CR) found only three stud-ies which met their inclusion criteria ofrandomized trials compared to another interven-tion with control groups.10–12 Two of these stud-ies compared cognitive rehabilitation with aplacebo treatment and one with occupationaltherapy treatment.12 All three studies showedimprovement following either intervention, how-ever, none of them found conclusive evidence forthe effectiveness of CR over the compared treat-ment. The majority of studies excluded from thereview were single cases or intervention withoutcomparisons (see review by Hayes and McGrath8

for an extensive list). However, Wykes et al.12

comparing neurocognitive remediation (NCR)(n = 17) with occupational therapy (n = 16) foundthat neurocognitive remediation six months postwas more effective in some of the executive func-tion measures and in self-esteem. This study hassome similarities to the current study, hence theirresults will be discussed further in comparison toours.

In addition, Spaulding et al.13 found that sig-nificant improvement was made on attention,

memory and executive functioning after sixmonths of cognitive treatment.

The present research, in line with both abovereviews, aimed to study the effectiveness ofFeuerstein’s Dynamic Cognitive approach forclients with schizophrenia in the community. Theuniqueness of this approach is in its combinationof two classical cognitive approaches: the reme-dial and the adaptive approaches.7,14 The studycompared cognitive and traditional occupationaltherapy treatments given to two randomized andmatched groups of schizophrenic clients.

Cognitive dysfunctions – which have beenidentified across a variety of domains includingmemory, attention, language and frontal systemsfunctioning – are the most typical disorders inschizophrenia. Attention deficits in schizophrenicclients are related both to selective15 and sus-tained16 attention. These deficits appear to berelated to difficulties in organization and dis-tractibility. Deficit in verbal memory and learn-ing appear to be more severe than in other areasof cognitive functioning.17 It is suggested thatmemory dysfunctions are related to the deficitthat exists in the encoding stage due to ineffi-ciencies in organization.18 It is speculated thatdisorder of thoughts and language in schizophre-nia are related to dysfunction of the left hemi-sphere.19,20 Frontal system functioning hasrevealed dysfunction in schizophrenia manifestedby difficulties in abstraction, sequential organiza-tion, fluency and planning. In addition, behav-iourally, some schizophrenic clients show a lackof motivation, others demonstrate impulse con-trol problems, and some may engage in bizarrebehaviour.21

Feuerstein’s theory of Structural CognitiveModifiability (SCM) maintains that individualcognitive structures can be changed at any ageand in any health status6,7,22 using the MediatedLearning Experience (MLE) interventionalapproach. According to Feuerstein, human learn-ing occurs either by direct exposure to a stimu-lus or indirectly via a human mediator betweenthe stimulus and the individual or between theindividual and his/her outcome.23 Insufficientopportunity to experience mediated learning willresult in deficient cognitive functioning or per-formance in the environment. Affected personscan be helped by exposure to MLE designed

350 N Hadas-Lidor et al.

Dynamic cognitive intervention in schizophrenia 351

in the community. Subjects were diagnosedaccording to the Diagnostic and statistical manualof mentally disordered, fourth edition – revised(DSM-IV)25 criteria by the treating psychiatrists.All the 72 participants were receiving stable med-ication and agreed to take part in this study aftersigning an informed consent. For the purposes ofthe study, the cohort was randomly assigned intotwo equal groups matched for gender, age, fam-ily status, education and subcategory of schizo-phrenia diagnosis. Eight clients were laterexcluded because of a change in their medicationor hospitalization, and six failed to complete theprogramme (which slightly altered the matching).The final sample included 58 clients, 29 in eachgroup, all of them agreed to participate in thestudy (Figure 2). Their demographic characteris-tics are shown in Table 1. The age range of theparticipants was 18–64 years, (mean 36, SD =10.29). T-test analysis showed no significant dif-ference between groups. Chi-square analysisyielded no significant between-group differencesin gender, level of education, number of hospi-talizations or years in rehabilitation.

specifically to meet their needs.14,22 Therapy isbased on four main elements: Reciprocity andintention; Transcendent nature of the mediatedinteraction; Mediation of meaning; and Media-tion of competence.22–24 Several components areused within the theoretical model for evaluationand treatment: (1). The Learning PotentialAssessment Device (LPAD)6 is a battery of testsfor dynamic assessment. It was developed to alterthe cycle of failure that low performers experi-ence on traditional intelligent tests: (2). Instru-mental Enrichment (IE) an interventionprogramme of more than 500 pencil-and-paperexercises.7,22 (3) The third component is the envi-ronmental context, namely the framework withinwhich the person conducts his/her life. The aimof this component is to adapt or create an envi-ronment that is as close as possible to a naturalcommunity environment.14

The theoretical model of dynamic cognitiveintervention through MLE in schizophrenia ispresented in Figure 1. The process relates to cog-nitive functioning, instrumental components ofactivities of daily living (ADL) both at work andin society, and self-concept. Its underlyingassumption is that an improvement in learningability leads to an increase in motivation, cogni-tive and functional skills.

The purpose of the present study was to exam-ine the efficacy of dynamic cognitive treatmentusing IE for clients with schizophrenia in a com-munity day rehabilitation programme. Wehypothesized that after about one year thoseclients who underwent IE would show signifi-cantly greater improvement in cognitive andfunctional abilities and self-concept than thosewho received conventional treatment.

Methods

SubjectsSeventy-two clients with schizophrenia in dif-

ferent stages of rehabilitation were initiallyenrolled in the study. This includes all the clientsthat were treated in the rehabilitation centre.Clients participated in a community day rehabil-itation centre at Petah-Tiqva in Israel. The maingoal of the centre is to find and adapt for theclients a suitable occupation and residence place

Table 1 Demographic characteristics of the study(Instrumental Enrichment programme) and control(traditional treatment) subjects with schizophrenia

Variables Study group Control group

Number % Number %

GenderMale 16 55.2 19 65.5Female 13 44.8 10 34.5

EducationElementary 8 28.6 6 20.7Secondary 14 50.0 20 69.0Higher 7 21.4 3 10.3

No. of hospitalizations1 10.7 6.92 17.9 31.03 50.0 34.54 21.4 27.6

Years in rehabilitationUp to one year 9 32.1 12 41.4Up to two years 9 32.1 7 24.1More than two years 11 35.7 10 34.5

No significant between-group differences were found byχ2 analysis.


Procedure and instrumentsThe procedure comprised a pretest, interven-

tion, and two stages of post-testing.

PretestPretest was given to both groups by an occu-

pational therapist and psychologist other than theones who were involved in the intervention. Thetest battery included the following instruments:

• Demographic questionnaire (gender, familystatus, education, working place, psychiatricdiagnosis and number of hospitalization).

• Three types of cognitive tests:1) Two from the LPAD: (a) The complexfigure drawing test figural memory), which isa dynamic version of Rey’s Complex Figure(RCF). This test consists of a complex geo-metric figure, composed of 18 elements, with

Figure 1 Model of dynamic cognitive intervention with schizophrenia.

Self-concept

Functional goals:Independence

Adequate social and IADL skillsReduction in abnormal behaviour


process) standardized in Israel,29 proof-reading, arithmetic exercises, arithmeticproblems and shape perception. (Accordingto the manual, these tests can be usedseparately to determine general aptitude.)

• Two functional outcome measures:1) Instrumental ADL (IADL) question-

naire.30

2) Work and Residence status scales:

both internal and external details.6,26 (b) Aword memory test (verbal memory), which isa dynamic version of Rey’s 16-word memorytest. This test consists of 16 words groupedinto four categories.6,26

2) The Raven Progressive Matrices (RPM)test (thought process).27,28

3) Four of the nine tests of the GeneralAptitude Test Battery (GATB) (thought

Figure 2 The study flow chart.

Losses (n = 14)8 due to changes in their

medication or hospitalization6 failed in the first evaluation

Experimental group (n = 29)Cognitive intervention by

means of IE

Control group (n = 29)Individual, group and

expression therapy

Pretest

Post-test(after one year)

Follow-up –Half year after

post-test

to improve special cognitive skills, like catego-rization, organization, orientation in space, etc.The client was given one or two paper-and-pencil exercises out of the available IE exercises(Table 2). The second part included an analysisof the paper-and-pencil exercise performance byboth the client and the therapist. The third partincluded examples from the client’s daily livingsituations, like work, residence or social skills,and demonstrated how the first exercise can ordid improved daily function. For example, if thefirst part deals with comparison and categoriza-tion, the third part can deal with organizing ashopping day.

Group treatment was also offered according toneed every few weeks and not always with thesame participants.32 The goals of group interven-tion were to enable the subjects to share a com-mon theme and enhance group belonging,develop their ability to see problems from dif-ferent perspectives, and develop their communi-cation skills. The duration of the programme wasone year.

The control group received traditional occupa-tional therapy treatment (functional tasks andexpressive activities), individually and in groups,by experienced occupational therapists, accord-ing to the same schedule and time frame as thestudy group.

Regarding work status, prior to the start ofthe intervention, all participants were work-ing at the adaptation unit in the rehabilita-tion centre. Therefore, work status was ratedaccording to three categories: (i) remained inthe adaptation unit; (ii) moved to anadvanced rehabilitation unit; (iii) hired on theopen market. Regarding residence status, thescale included living either (i) in a shelteredhouse; (ii) with parents; or (iii) indepen-dently.

• Fitts Self-Concept Scale.31

InterventionIntervention for the study group consisted of

two- to three-weekly one-hour sessions of IE inthe rehabilitation centre. The IE is divided into15 tools (Table 2), each focusing on a specificcognitive deficiency, while at the same time relat-ing to the acquisition of the necessary conditionsand skills required for learning.7,22 Treatment wasgiven by occupational therapists trained in thismethod on an individual basis and was adaptedto each subject’s abilities and needs, as deter-mined by the pretest evaluation. The goalswere to improve the subject’s cognitive adaptiveability and independence (IADL and occupa-tional) and to sharpen their awareness of theirabilities. Each session was divided into threeparts: The first part included cognitive exercises


Table 2 The cognitive areas, instruments and modalities included in the Instrumental Enrichment programme

Cognitive Instrument Modalityarea/components

Organization Organization of dots Graphic Analytic perception Graphic

Comparison and Comparison Verbal, graphic, paintingcategorization

Categorization Verbal, graphic, painting, numericTransitive relation Verbal, painting, Syllogism Verbal, painting,

Orientation in space Orientation in space I Verbal, graphicOrientation in space II Verbal, graphic

Relations Temporal relations Verbal, graphic, paintingFamily relations Verbal, graphic, paintingNumerical relations Verbal, graphic, painting, numericInstructions relations Verbal, graphic

Social skills Illustrations (cartoons) Painting

Integrative thinking Stencil design Graphic


ANOVAS of each index showed significant dif-ferences between groups on the change frombefore to after treatment in all indices exceptarithmetic exercises (Table 3).

Daily functionThe first functional measure, IADL, rated

before and immediately after treatment, showedno between-group difference at either time point.Differences were significant, however, for workand residence status, measured before treatmentand at follow-up six months after termination ofthe programme (at 18 months). Figure 3 andTable 4 show that approximately 30% of the con-trol group (nine subjects) remained in the adap-tation unit, though none of the study group did;46% of the control group (14 subjects) moved toother advanced rehabilitation units comparedwith 69% of the study group (20 subjects); and14% of the control group (five subjects) wereworking in the open market compared with 31%of the study group (nine subjects). These differ-ences were significant by 3 × 2 chi-square analy-sis (χ2 = 14.30, df = 2, p < 0.001).

Regarding residence status, by the end of theprogramme, 44.4% of the study group (13 sub-

Post-testingPost-testing by the same testers was conducted

in two stages: stage one was conducted towardsthe end of the programme after about one yearwith the same instruments as pre-testing. Stagetwo included a follow-up interview that was con-ducted six months after completion of the pro-gramme to evaluate work and residence status.

Results

Results are presented according to the threeareas studied.

Cognitive abilityTable 3 presents the means and standard devi-

ations of the scores of the two groups on the twomemory indices (figural and verbal) and the fivethought process indices (Raven matrix and fourGATB tests) before and after treatment.MANOVA revealed significant differencesbetween the two groups for both memory andthought process favouring Instrumental Enrich-ment (F(2.52) = 13.75, p < 0.001; and F(1.46) =7.28, p < 0.001, respectively). Separate post-test

Table 3 Scores for the cognitive measures for both groups before and after intervention (mean ± SD) and post-testANOVA for the mean difference in each index

Measures Study group (n = 29) Control group (n = 29) Analysis ofvariance

Before After Before After F(1.52)

LPAD: Complex figure drawing test 15.40 19.18 11.32 13.39 5.47*(6.42) (7.79) (4.24) (5.49)

LPAD: Word memory test 6.30 10.71 6.82 7.89 19.11**(2.51) (2.81) (2.84) (2.54)

Raven Progressive Matrices 35.45 38.04 28.89 29.11 205.07***(9.94) (7.45) (11.54) (10.69)

GATB:Proofreading 33.54 37.77 23.04 23.04 7.29*

(16.04) (15.83) (12.29) (11.16)

Shape perception 10.85 13.77 8.12 7.62 10.51**(4.38) (6.59) (4.24) (4.40)

Arithmetic problems 7.85 9.19 6.50 6.42 5.92*(3.56) (4.03) (3.67) (3.20)

Arithmetic exercises 16.12 19.58 12.85 12.92 0.79(5.89) (5.42) (5.03) (5.68)

*p < 0.05, **p < 0.01, ***p < 0.001.LPAD, Learning Potential Assessment Device.


with schizophrenia and validate our inclusioncriteria.

Discussion

The unique contribution of this study is the suc-cessful use of a structured cognitive interventionmodel in a schizophrenic population in commu-nity rehabilitation. The study hypotheses weresupported for almost all cognitive componentsand for work and residence status. The hypothe-ses in relation to IADL and self-concept were notsupported, raising also the issue of schizophrenicclients’ self report.

jects) had moved to a hostel or independent res-idence compared with only 17.4% of the controlgroup (five subjects) (χ2 = 3.86, df = 1, p < 0.05)(Figure 4 and Table 5).

Self-conceptNo significant differences were found on the

Fitts Self-Report Scale scores either before orafter treatment for any of the groups. It is note-worthy that comparison of the mean score of self-concept of each of the groups (278.61 and 278.77)with the normative mean (345.57)31 showed thatin both, self-concept was lower than the norm.These findings are in accord with the data of Fittson the self-concept profile of subgroups of clients

Figure 3 Work status changes in study and control group at follow-up. χ2 (2 groups, 3 workstatus) = 14.30, df = 2, p < 0.001.

Research group (n = 29)

Control group (n = 28)

Table 4 Work status changes in study and control group at follow-up

Research group (n) Control group (n)

Adjustment unit 0 9Rehabilitation unit 20 14Independent work 9 5

χ2 (2 groups, 3 work status) = 14.30, df = 2, p < 0.001.


This work has important theoretical and clini-cal implications. To the best of our knowledge,this study is the longest (one year, 100 hours oftreatment) controlled intervention studyreported in the literature. Previous works havedescribed only short-term protocols or case stud-ies.13,21,33 As such, our results question the classicview of schizophrenia as a disease with continu-ous deterioration in cognitive performance thatcannot be altered, and agrees with Feuerstein’stheory of structural cognitive modifiability thatchanges can be achieved with long systematiccognitive dynamic intervention. In the same vein,Wykes et al.12 also demonstrate some improve-ments six months post neurocognitive interven-tion.

Our intervention study also demonstrates whatGreen et al.1 referred to by focusing on learning

Figure 4 Residence status in study and control group at follow-up.aLived in sheltered house or with their parents. bMoved from theirparents’ house to a hostel or independent dwelling. χ2 (2 groups, 2residence status) = 3.86, df = 1, p < 0.05.

Did not changea

Changedb

Table 5 Residence status in study and control group at follow-up

Research group (n) Control group (n)

Changeda 13 5Did not changeb 16 24

aLived in sheltered house or with their parents.bMoved from their parents’ house to a hostel or independent dwelling.χ2 (2 groups, 2 residence status) = 3.86, df = 1, p < 0.05.

Clinical messages

• The Mediated Learning Experience (MLE)approach is applicable to all rehabilitationareas (work, residence and social skills) andnot only to the cognitive area.

• The Instrumental Enrichment (IE) pro-gramme should be included as a permanentpart of the therapeutic programme for schiz-ophrenic clients in remission, in heteroge-neous environments.

• Clinicians need to provide these clients witha more varied community system to easetheir gradual progression to more intellec-tually stimulating and heterogeneous envi-ronments, in accordance with their progress.


AcknowledgementsWe gratefully acknowledge the support and

assistance of Michal Avrech Bar for reading thedrafts of the article and editing it. We want tothank the staff and clients of the rehabilitationcentre at Petah-Tiqva.

References

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potential as the mediating variable between cog-nitive deficits and functional outcomes. The find-ings provide experimental support of the efficacyfor this dynamic structured intervention com-pared with traditional treatment. After about oneyear of IE, significant differences between thestudy and control groups were found for almostall cognitive measures and in work and residencestatus. Although changes also occurred in the tra-ditional treatment, the structured dynamic cogni-tive programme helped the clients to improvetheir thinking strategies and processes andthereby possibly to improve their everyday occu-pational functioning and living status.

No significant between-group differences werefound in the IADL or self-concept scales. Boththese domains were measured by self-reportquestionnaire. This may be a limitation and aninappropriate method for evaluating the schizo-phrenic population, which is characterized by lowself-esteem and feelings of incompetence, even inthe face of real progress. This gap betweenclients’ actual performance and their perceptionof it dictates the need for long periods of time forthese individuals to accept and acknowledgechanges. We suggest that for more precise deter-mination of change, self-report questionnaires bereplaced by performance tests with structuredrating scales conducted under close observationsuch as the Assessment of Motor and ProcessScales (AMPS).34 However, we need also to con-sider the opposite findings of Wykes et al.12 whofound improvement in self-esteem using theRosenberg Self-esteem Scale following theirintervention. Further investigation into the issueof the impact of cognitive interventions on self-concept or self-esteem in schizophrenia has to beundertaken.

In summary, we present an existing model ofcognitive intervention that has been implementedfor the first time in treating individuals with schiz-ophrenia who are in the process of rehabilitationin the community. The significant improvementof the participants in cognitive ability and insome aspects of work and residence providesstrong support for the possibility of effecting cog-nitive functional changes in this population bymeans of instrumental enrichment.


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