Nonverbal Learning Disabilit) School Behavior, and Dyslexia Nathlie A. Badian Holbrook Public Schools Holbrook, Massachusetts The Children's Hospital Boston, Massachusetts Harvard Medical School

The aims of the study were to investigate whether children showing a low nonverbal~high verbal (LNV) WISC-R profile are more likely to exhibit behaviors conducive to school failure than children with a low verbal~high nonverbal (LV) profile, and to examine the relationships among these behaviors, the LNV/LV profiles, and reading ability. The 65 subjects included 27 LNV and 38 LV children, aged 5 to 11 years. Results confirmed earlier findings (Badian 1986) that LNV children are perceived by their teachers as significantly poorer than LV children in many behaviors associated with school success. There was a dichotomy, however, between LNV good and poor readers. All LNV subjects displayed problems in organizational skills, but those who were dyslexic were poorer in social behavior (e.g., acceptance of criticism and peer relationships) than either LNV good readers or LV good or poor readers. It was concluded that children with a low nonverbal~high verbal profile and a probable right hemisphere dysfunction, who appear to be dyslexic in the early school years, are at high risk for both social behavior problems and school failure, and that these children are a more high-risk group than poor readers with a low verbal~high nonverbal profile. Annals of Dyslexia, Vol. 42, 1992. Copyright © 1992 by The Orton Dyslexia Society ISSN 0736-9387

159

160

O~cnvs, ParrE~s,

~¢v

PROCNOSES

For more than two decades there has been massive research focused on language disorders, including dyslexia, which are strongly associated with dysfunction of the left cerebral hemisphere. Comparatively little attention has been given to learning problems and behaviors believed to be associated with right hemispheric dysfunction. Evidence has been accumulating, however, that the child or adult with a pattern of strengths and weaknesses that suggests a right hemispheric dysfunction is impaired in many adaptive behaviors (Badian 1983, 1986; Denckla 1978; Rourke 1982, 1988; Tranel et al. 1987; Voeller 1986; Weintraub and Mesulam 1983). In their recent review of right hemispheric dysfunction in nonverbal learning disabilities, Semrud-Clikeman and Hynd (1990) point out that many different terms have been used to classify children with a profile suggestive of right hemispheric dysfunction. The term most frequently used for this type of dysfunction is a nonverbal disorder of learning or nonverbal learning disability (Johnson and Myklebust 1967; Myklebust 1975). Johnson and Myklebust stated that their "experience with children who have deficits in learning clearly reveals that in many instances their greatest, if not their only, problem is in nonverbal learning" (1967, p. 44). The child who has a nonverbal learning disability has a significantly higher Verbal than Performance IQ and is usually good at word recognition and spelling, but tends to be poor in arithmetic. Rourke and his colleagues have carried out extensive research comparing children showing this school achievement profile with those showing the reverse characteristics: poor in reading and spelling, but comparatively strong in arithmetic (e.g., Ozols and Rourke 1985; Rourke 1978, 1982; Rourke and Finlayson 1978; Rourke and Strang 1983; Strang and Rourke 1983, 1985). Characteristics frequently displayed by children with a deficit in arithmetic indude poor visual-spatial organization, disturbed body image, disorientation in time and space, social imperception, and social immaturity (Johnson and Myklebust 1967, pp. 248-250). Research confirms that children who are satisfactory readers but poor in arithmetic tend to have problems in social learning and adaptive behavior (Badian 1986; Badian and Ghublikian 1983; Ozols and Rourke 1985; Rourke 1982, 1988; Rourke and Fisk 1981; Strang and Rourke 1985). There have been many case studies and descriptions of children and adults with a nonverbal learning disability or developmental learning disability of the right hemisphere (e.g., Badian 1983, pp. 258259, 1986; Rourke 1989, pp. 151-201; Rourke et al. 1983, pp. 238-253; Tranel et al. 1987; VoeUer 1986; Weintraub and Mesulam 1983). Children with nonverbal learning disabilities have been described as having difficulty interpreting nonverbal social cues (e.g., facial expressions), processing novel stimuli, and expressing emotion appropriately through

161

N ONIrERBAL LZARNING DISABILITY

voice or facial expressions (Ozols and Rourke 1985), as talkative, but with a tendency to use jargon, and as clumsy (Strang and Rourke 1985), and as showing signs of an attention deficit disorder (Voeller 1986). Characteristics attributed to older teenagers and adults include shyness and introversion, inability to display affect, chronic emotional difficulties, poor social perception, and poor visuospatial skills (Tranel et al. 1987; Weintraub and Mesulam 1983). Depressive illness in children has also been shown to be associated with right hemispheric learning disabilities (Brumback and Staton 1983). Recently, it was pointed out that the nonverbal learning disability may be associated with a predisposition to adolescent and adult depression and suicide (Rourke, Young, and Leenaars 1989). Rourke and his colleagues have strongly espoused the position that central processing deficiencies can lead both to learning disabilities and to socio-emotional disturbances (Ozols and Rourke 1985, p. 296; Rourke 1982, 1988; Rourke and Fisk 1981). More specifically, the nonverbal learning disability seems to approximate a sufficient condition for the development of some sort of socio-emotional disturbance, whereas the pattern of central processing abilities and deficits exhibited by the psycholinguistically impaired child does not (Rourke 1988). Boys with a nonverbal learning disability are not only lower in arithmetic than reading, but demonstrate behaviors which teachers find irritating and which predispose them to school failure (Badian 1986). Such behaviors include poor school work habits (e.g., slow to get started or to finish), low motivation, disorganization (e.g., losing things, untidiness, forgetfulness), poor peer relationships, dependenc3~ and difficulty accepting criticism. Informal follow-up of children shows that these behaviors distinguish such children from their peers more dramatically, when they reach the upper elementary grades. The aims of the study here presented were: (1) to investigate the validity of findings that children showing a profile believed to be assodated with right hemispheric dysfunction are more likely to exhibit behaviors conducive to school failure than children with an apparent left hemispheric dysfunction (Badian 1986); and (2) to examine the relationships among these behaviors, low nonverbal and low verbal profiles associated with right and left hemispheric dysfunction, and reading ability.

Method Subjects The study sample was drawn from a pool of 239 children, aged 5 to 11 years, who were tested for school learning and behavior problems.

162

Omcnvs, PAvrEmcs, ,,avp PRo~lvosEs

The children all lived in a suburban, lower-middle-to-middle socioeconomic class community, with a predominantly white population. Testing included the WISC-R (Wechsler 1974) for most subjects, but some young children, aged 5 to 6 years, had been given the WPPSI (Wechsler 1963) or the WPPSI-R (Wechsler 1989). Sample selection criteria were: Full Scale IQ between 80 and 120, a difference of 15 or more points between Verbal and Performance IQ (in either direction), English the primary language, and placement in a regular class for more than half the day. Among the 239 potential subjects, 73 (30.5 percent) had a Verbal/Performance IQ discrepancy of at least 15 points. Eight of the 73 did not meet another of the criteria, leaving 65 subjects (43 boys, 22 girls). Mean age of the sample was 7.9 years (SD 1.7). Mean IQs were Verbal, 99.2 (SD 13.5), Performance, 102.2 (SD 14.0), Full Scale, 100.4 (SD 9.4). There was no difference between boys and girls in IQ: Verbal, F(1,63) = 0.08, p.7835, Performance F(1,63) = 0.36, p.5517, Full Scale, F(1,63) = 0.03, p.8736. Measures

As part of the evaluation, classroom teachers were asked to rate each subject on a checklist of behaviors: Teacher Behavioral Assessment (TBA), using a 4-point scale. The TBA is based on earlier research on nonverbal learning disorders (Badian 1986). Behaviors induded are: Motivation, Work Habits, Independence, Following Directions, Organization, Written Work, Appropriate Behavior, Acceptance of Criticism, and Peer Relationships. Poor performance on each behavior is defined on the checklist. The TBA is shown in Table I. As children were rated by regular classroom teachers, the comparison group for ratings was the normal peer group. All but four children were also administered individual school achievement tests, which included the Kaufman Test of Educational Achievement (K.TEA) (Kaufman and Kaufman 1985) for those in first grade or above, and the Achievement section of the Kaufman Assessment Battery for Children (K.ABC) (Kaufman and Kaufman 1983) for kindergarten children, as the K.TEA is not normed for children below first grade. The K.TEA and K.ABC subtests used are listed below: Kaufman Test of Educational Achievement Reading Decoding (word reading), Reading Comprehension, Spelling (writing of dictated words), Mathematics Computation, Mathematics Applications. Kaufman Assessment Battery for Children Reading Decoding (letter naming, word reading), Arithmetic. Standard scores (M 100, SD 15) based on age were used for all school achievement tests.

NONVERBAL LEARNING DISABILITY

Table I Teacher Behavioral Assessment Below Poor Average Average

163

Above Average

1. Motivation 2. Work Habits 3. Independence 4. Following Directions 5. Organization 6. Written Work 7. Appropriate Behavior 8. Acceptance of Critisicm 9. Peer Relationships Poor performance might include: 1. Motivation: Makes little effort, does not participate, uncooperative, poor attitude. 2. Work Habits: Slow to get started or to finish, dawdles, daydreams, seldom finishes. 3. Independence: Cannot work without help, immature, cannot take ageappropriate responsibilities. 4. FollowingDirections: Has to be given directions individually, or several times, or one at a time. 5. Organization: Loses things, untidy desk, untidily dressed, forgets to bring homework etc. to school, forgets long-term assignments. 6. Written Work: Messy, untid~ poorly organized on paper, poor handwriting. 7. Appropriate Behavior: Makes noises, hums, sings, talks excessively without permission, plays with pencils, fingers etc., drums fingers. 8. Acceptance of Criticism: Becomes angry or arrogant when criticized, argues, contradicts, cannot accept teasing. 9. PeerRelationships: A loner, not liked by other children, mean to others, gets along better with adults or younger children, titan with peers.

Subject Groupings The subjects were divided into two groups based on the direction of the Verbal IQ/Performance IQ discrepancy. The 27 subjects w h o s e

164

OP~aXlvs, PAVr~RNS, AND PROCNOSES

Verbal IQ was higher than Performance formed the Low Nonverbal (LNV) group, and the 38 who showed the reverse profile formed the Low Verbal (LV) group. Each subject was also classified as a good or poor reader. Poor reading was defined as a standard score for Reading Decoding, Reading Comprehension, or Spelling below the 25 percentile for age (i.e., < 90), and good reading as standard scores > 90 on these tests. The four subjects to whom no individual achievement tests had been given (2 LNV, 2 LV) were classified as good or poor in reading based on percentile ranks on the group-administered Stanford Achievement Test, but no scores were entered for them. All four were good readers. The criteria yielded 34 poor and 31 good readers. Group distribution by gender was: LNV: Good readers, 8 boys, 8 girls; Poor readers, 9 boys, 2 girls; LV: Good readers: 10 boys, 5 girls; Poor readers, 16 boys, 7 girls. Mean chronological ages, IQs, and WISC-R factors (Kaufman 1979) are shown in Table II for the groups. Subtests comprising the WISC-R factors are: Verbal Comprehension (VC): Information, Similarities, VocabularF Comprehension; Spatial Organization (SpO): Picture Completion, Picture Arrangement, Block Design, Object Assembly; Freedom from Distractibility (FFD): Arithmetic, Digit Span, Coding. The groups did not differ in age: F(3,61) = 0.82, p.4886, Full Scale IQ: F(3,61) = 0.80, p.4992, nor on the FFD factor: F(3,58) = 2.02, p.1210. They differed not only in Verbal and Performance IQs, but also on the VC and SpO factors, because of selection criteria. Procedures

Each behavior rated on the TBA was scored from 1 (Poor) to 4 (Above average) to give nine behavior scores and a total score for each subject. As MANOVA showed that boys and girls did not differ on the TBA: F(9,56.25) = 1.01, p.4408, nor on any univariate comparison, no separate analyses were made for gender. The TBA behaviors were factor analyzed (Varimax rotation of eigenvalues > 1.0) to aid in interpreting the behaviors. Groups were compared on the TBA behaviors, the factors derived from the behaviors, and on the total TBA. A 2-factor analysis of variance was carried out, with nonverbal/verbal profiles and reading ability as the factors. Groups were also compared on school achievement. As the groups did not differ in Full Scale IQ or age, there were no covariates. Correlations between each TBA behavior and age were all near zero. Developmental questionnaires were filled out by 86 percent (56/65) of the subjects' parents. These questionnaires included birth weight, birth histor3~ and medical history. Percentages of those responding were similar for the LNV and LV groups (LNV: 85 percent; LV 87 percent). Groups were compared on birth weight, birth historF and medical history.

12.4

8.6

9.8

FFD Factor

Full Scale IQ

SpO Factor

90.3

102.0

Performance IQ

VC Factor

112.6

8.3

Mean

Verbal IQ

Age (years)

Variable

1.6

1.5

1.5

9.6

10.0

7.0

2.0

SD

8.7

8.7

12.3

99.8

89.1

110.2

7.5

Mean

1.1

1.7

1.6

9.7

9.5

8.6

1.8

SD

Low Nonverbal Good Poor Readers Readers n = 16 n = 11

9.3

8.6

12.4

101.1

89.9

111.6

8.0

Mean

Total

1.5

1.6

1.5

9.5

9.6

7.6

2.0

SD

10.1

11.6

8.8

102.3

112.5

93.4

7.6

Mean

1.3

1.8

1.5

1.4

9.3

8.7

8.6

9.2

11.4

8.3

98.2

110.0

88.3

8.0

Mean

1.6

1.4

1.5

9.3

9.3

8.8

1.5

SD

Low Verbal Poor Readers n = 23

SD

Good Readers n = 15

9.5

11.5

8.5

99.8

111.0

90.3

7.8

Mean

Total

Table II Mean Ages, IQs, and WISC-R Verbal Comprehension (VC), Spatial Organization (SpO), and Freedom from Distractibility (FFD) Factor Scores of Groups Defined by Low Nonverbal/Low Verbal Profiles and Reading Ability

1.7

1.4

1.5

9.4

9.0

8.9

1.4

SD

166

OP.ZGZNS,PAITERNS, AND PROGNOSES

Results Factor Analysis The factor analysis of the TBA for the 65 subjects showed that it consisted of two factors, with Factor I accounting for 54.55 percent of the variance, and Factor II for 16.5 percent. Factor I included (in order of importance) Organization, Written Work, Following Directions, and Independence, and Factor II consisted of Peer Relationships, Acceptance of Criticism, Appropriate Behavior, and Motivation. Work Habits split across the two factors. Factor I appears to be primarily an organization factor, and Factor II a social behavior factor. The factor analysis is shown in Table III. These results are consistent with two other factor analyses of the TBA for referred children (N = 153, N = 115), each of which yielded two similar factors, interpreted as organization and social behavior. Thus, the TBA appears to consist of two reliable, stable factors for children referred for evaluations. Comparison of Groups on the Teacher Behavioral Assessment Mean TBA scores of the groups, defined by nonverbal/verbal profiles and by reading abilit3~ are shown in Table W. Groups differed for the nonverbal/verbal factor on each behavior, on both factors, and on the total TBA score, with the LNV group lower. Significant differences for the reading ability factor were found on Motivation, Work Habits, Appropriate Behavior, Acceptance of Criticism, Peer Relationships, and Factor II, with poor readers lower. There was only one significant

Table III Rotated Factor Loadings of Behaviors on the Teacher Behavioral Assessment Behavior Factor I Factor II Communality Motivation .347 -.601 .482 Work Habits .592 -.553 .657 Independence .747 -.251 .621 Following Directions .806 -.208 .693 Organization .879 - . 175 .803 Written Work .860 -.185 .774 Appropriate Behavior .370 -.804 .783 Acceptance of Criticism .140 - .869 .775 Peer Relationships .091 -.893 .806 Eigenvalue 4.91 1.49 Percent of variance 54.55 16.,50

3.00 3.09 22.78

Peer Relationships

Total Score

Organization

Acceptance of Criticism

1.97

Following Directions 1.94

2.22

Independence

2.84

2.38

Work Habits

Appropriate Behavior

2.31

Motivation

Written Work

2.84

Behavior

4.6

0.5

0.5

0.7

0.8

0.8

0.8

0.8

0.9

0.9

Good Readers

19.00

2.27

2.09

2.18

1.73

1.73

2.09

2.45

1.55

2.64

4.0

0.8

0.7

0.9

0.8

0.9

0.8

1.0

0.7

0.7

Low Nonverbal Poor Readers Total

21.24

2.76

2.63

2.57

1.85

1.87

2.17

2.41

2.00

2.76

4.7

0.7

0.7

0.8

0.8

0.8

0.8

0.9

0.9

0.8

28.27

3.20

3.20

3.40

2.87

2.93

2.87

2.97

3.27

3.57

3.4

0.4

0.6

0.5

0.4

0.6

0.6

0.7

0.6

0.5

Good Readers

25.43

2.91

3.00

2.83

2.57

2.78

2.61

2.91

2.78

2.91

5.1

0.8

0.7

1.0

0.9

0.7

0.7

0.7

0.9

0.6

Low Verbal Poor Readers

26.60

3.02

3.08

3.05

2.68

2.84

2.71

2.93

2.97

3.17

Total

Table W Mean Scores of Groups Defined by Low Nonverbal/Low Verbal Profiles and by Reading Ability on the Teacher Behavioral Assessment

4.7

0.2

0.7

0.9

0.7

0.7

0.7

0.7

0.8

0.6

168

OmGXNS, PAYdaYS, AND PROalVOSES

interaction: Acceptance of Criticism (F = 4.60, p.0360). The analysis of variance results are shown in Table V, together with the results of post hoc testing of between-group differences (Duncan's Multiple Range

Test). As Table V indicates, Independence was the only behavior on which no significant between-group differences were observed. Both LV groups (i.e., good and poor readers) were superior to both LNV groups on Organization, Written Work, and Factor I, but there was no behavior on which both groups of poor readers differed from both groups of good readers. The LNV good readers were superior to LNV poor readers on Appropriate Behavior, Acceptance of Criticism, Peer Relations, and Work Habits, but the LV good readers were superior to LV poor readers only on Motivation. Behaviors on which LNV and LV poor readers, LNV and LV good readers, LNV good and poor readers, and LV good and poor readers differed significantly are listed in Table VI. Differences between the four groups (LNV good and poor readers, LV good and poor readers) on the two TBA factors (Organization, Social Behavior) are shown in Figure 1. Figure I illustrates that LNV children were inferior to LV children on the organization factor, irrespective of reading abilit3~ but that LNV good readers, as well as LV good and poor readers, were superior to LNV poor readers on the social behavior factor. Group Differences in School Achievement

Mean standard scores of each group on the school achievement tests are shown in Table VII. The groups differed significantly on all aspects of achievement tested: Reading Decoding, F(3,57) = 39.92, p.0000, Reading Comprehension, F(3,51) = 23.41, p.0000, Spelling, F(3,52) = 25.27, p.0000, Mathematics Computation or Arithmetic, F(3,57) = 9.35, p.0000, Mathematics Applications, F(3,51) = 3.19, p.0313. Post hoc tests showed that for the two reading subtests and spelling significant between-group differences were: LNV good readers > LV good readers > LNV poor readers = LV poor readers. For Mathematics Computation, group differences were: LNV good = LV good readers > LNV poor = LV poor readers. For Mathematics Applications, the LNV good readers were superior to the LV poor readers. Birth and Medical History

Complications at the time of labor and delivery were defined as: breech presentation, rotation, placenta previa, long labor (> 24 hours), cord around neck, breathing problems, transfusions needed. Low birth weight was defined as a weight less than 5 lbs. 12 ozs. Using these definitions, 30 percent of LNV children, but no LV children, had a history of birth complications, and 30 percent of LNV

O~

11.25 4.69 27.10 18.89 5.99

Acceptance of Criticism

Peer Relationships

Total Score

TBA Factor I

TBA Factor II

.0173

.0001

.0000

.0343

.0014

.0056

.0000

.0000

.0031

.0131

.0000

.0061

14.47

0.05

8.34

10.33

11.25

8.75

1.76

1.04

1.04

0.00

9.66

5.99

.0003

.8280

.0054

.0021

.0014

.0044

.1900

.3121

.3117

.9499

.0029

.0173

Factors Reading Ability F(1,61) p

1.76

0.51

0.17

2.40

4.60

0.04

0.06

0.06

0.12

0.11

0.49

1.61

.1896

.4778

.6799

.1266

.0360

.8338

.8140

.8143

.7320

.7468

.4848

.2096

Interaction F(1,61) p

1 =3=4 > 2

3= 4 > 1= 2

3 > 1 =2, 4 > 2

1 =3=4 > 2

1 =3=4 > 2

1 =3=4 > 2

3=4 > 1 =2

3=4 > 1--2

3 > 1 =2

3 > 1 > 2, 4 > 2

3 > 1 =2=4

Post H o c Comparisons*

*Groups: 1 = Low Nonverbal Good Readers, 2 = Low Nonverbal Poor Readers, 3 = Low Verbal Good Readers, 4 = Low Verbal Poor Readers.

8.26

A p p r o p r i a t e Behavior

20.95

9.50

Following Directions

Written Work

6.54

Independence 27.56

29.63

Work Habits

Organization

8.07

Motivation

Variable

Nonverbal/Verbal F(1,61) p

Table V Analysis of Variance: Results of G r o u p C o m p a r i s o n s for the Nonverbal/Verbal a n d Reading Ability Factors o n the Teacher Behavioral A s s e s s m e n t (TBA)

170

O~ctNs, P.4vrggNs, AND PROCNOSES

Table VI Behaviors on which Groups of Children, Defined by Low Nonverbal/Low Verbal Profiles and by Reading Ability, Differed Significantly

Poor Readers LNV < LV Work Habits Organization Written Work Behavior Criticism Peer Relationships

Group Comparisons Low Nonverbal Good Readers Poor Readers LNV < LV < Good Motivation Work Habits Directions Organization Written Work

Work Habits Behavior Criticism Peer Relationships

Low Verbal Poor Readers < Good Motivation

LNV = Low Nonverbal, LV = Low Verbal, Behavior = Appropriate Behavior, Directions = FollowingDirections, Criticism = Acceptanceof Criticism. children, compared with 6 percent of LV children, were of low birth weight. If cases of low birth weight and cases with perinatal complications are combined, 52 percent (12/23) of LNV children, compared with 6 percent (2/32) of LV children, had a less than favorable start in life. Seizures in the first few years of life occurred among 4.4 percent of LNV and in 9.1 percent of LV cases. There was one fractured skull and one case of meningitis in the LNV group, and one case of concussion and one of temporary paralysis following an accident in the LV group. When tested as prekindergarten children, similar percentages of the LNV and LV groups were rated as overactive or inattentive. Two subjects in each group later took stimulant medication for an attention deftcit hyperactivity disorder.

Discussion The impetus for this study was earlier research demonstrating that boys with low nonverbal abilit~ in relation to verbal, were inferior to boys with the reverse profile in behaviors associated with school success (Badian 1986). The behavioral checklist used in this study (Teacher Behavioral Assessment) was based on the results of the earlier study. The present study differed from the earlier one in that girls were included, and the children were two and a half years younger, on average. Because some of the youngest children had been administered the WPPSI, rather than the WISC-R, Verbal/Performance IQ differences

NONVERBAL LEARNING DISABILITY

171

ORG .-

.

.

.

.

•

SOC

+1.0-

\

+.5-

l/lIt

_

--.5--

-1.0-

LNVG

LNVP

FACTOR SCORES

LVG ORG

LVP SOC

Figure 1. Mean factor scores of low nonverbal good (LNVG) and poor (LNVP) readers, and low verbal good (LVG) and poor (LVP) readers on the organization ( ORG) and social behavior (SOC) factors of the Teacher Behavioral Assessment.

were used to define groups, rather than the difference between two Verbal and two Performance scale subtests, as in the earlier study. In spite of the methodological differences, the present study strongly confirms the earlier findings that children with low nonverbal ability are perceived by their classroom teachers as inferior to children with low verbal ability in behaviors important to success in school. The interaction of the nonverbal/verbal ability factor with reading ability was also examined in this study. Among the children with low nonverbal ability 41 percent were below average in reading. If a significant discrepancy between Verbal IQ and reading standard scores is used to define dyslexia, these low nonverbal poor readers would be considered dyslexic. The low nonverbal subjects who did not have deficits in reading were similar to the low nonverbal dyslexic subjects in some behavioral characteristics, but not others. The two low nonverbal groups did

",4

107.0 103.5 105.0 107.4 102.4

Reading Decoding Reading Comprehension

Spelling Mathematics Computation* Mathematics Applications

7.4 7.0 8.9

9.1 8.8

SD

86.6 94.8 94.9

86.2 88.2

Mean

10.2 11.0 11.5

8.4 8.3

SD

Poor Readers

97.3 101.9 99.3

97.8 97.1

Mean

SD

12.5 10.9 10.5

13.6 11.4

Total

*Includes K.TEA Mathematics Computation and K.ABC Arithmetic.

Mean

Variable

Good Readers

Low Nonverbal

95.4 105.4 98.9

98.2 95.6

Mean

3.4 10.4 8.6

4.9 3.5

SD

Good Readers

86.1 91.3 92.6

85.9 85.3

Mean

5.6 11.8 9.1

5.6 4.8

SD

Poor Readers

Low Verbal

89.6 96.4 95.1

90.3 89.0

Mean

8.0 6.6

SD

6.7 13.1 9.3

Total

Table VII Mean Scores of Groups Defined by Low Nonverbal/Low Verbal Profiles and by Reading Ability on School Achievement Tests

N O ~ R S A L LKaaN~NC DXSASILXTY

173

not differ in Motivation, Independence, Following Directions, Organization, and Written Work. All of these behaviors, except Motivation, loaded on Factor I of the Teacher Behavioral Assessment checklist. The behaviors on which the two groups differed significantly: Work Habits, Appropriate Behavior, Acceptance of Criticism and Peer Relationships, all loaded on Factor II, which was a social behavior factor. Thus, one group of low nonverbal children referred for testing did not show deftcits in reading (or mathematics), but, nevertheless, was not doing well in school because of problems in responsibility, motivation, organizing and producing written work, carrying out teacher directions, etc. The low nonverbal poor readers (or dyslexic group) not only had these problems, but also had poor social behavior. In the low verbal group a higher proportion (61 percent) was below average in reading. As most of these poor readers were reading at the level expected by their Verbal IQs, they could be considered to be "garden variety" poor readers (Stanovich 1988). Although in the low verbal group poor readers were lower than good readers in arithmetic, as well as in reading, the two groups differed on only one behavior: Motivation. Whether the low motivation of the poor readers was the cause of their poor school achievement or its result cannot be determined. However, in contrast to the low nonverbal poor readers, the low verbal poor readers were rated as average (in relation to their normal classmates) in most behaviors, including peer relationships. Although the two groups of poor readers did not differ in reading and mathematics, the low verbal group was superior in behaviors associated with both the organization and the social behavior factors. The only behaviors on which the two groups of poor readers did not differ were Motivation, Independence, and Following Directions. When the two groups of good readers were compared, the low verbal subjects were superior to the low nonverbal group in Motivation, Work Habits, Following Directions, Organization, and Written Work. With the exception of Motivation, all of these behaviors loaded on the organization factor, and most of them were those on which the low nonverbal good and poor readers did not differ. Rourke (1989, pp. 136-137) stresses that a significantly higher Verbal than Performance IQ can occur for many reasons, and that this alone is not sufficient for diagnosis of the nonverbal learning disabilities (NLD) syndrome. All, or most, of the other elements of the syndrome, such as deficits in visual or tactile perception, weaknesses on complex motor tasks, and weaknesses in dealing with novel stimuli, should be present. Not all subjects of this study had received extensive testing in these areas, but a high proportion of the low nonverbal group had problems with visual perception or visual-motor skills, and at least 26 percent of them received occupational therapy for these deft-

174

ORIGINS, PAI"TIIRNS, AND PROGNOSES

cits, compared with only 3 percent (one child, following a serious accident) of the low verbal group. The low nonverbal subjects of this study differ from the children with a nonverbal learning disability described by Rourke (1989), and from the subjects of the study on which the present one is based, in that they did not show a deficit in arithmetic, in relation to their word recognition and spelling. Age may account for this difference. Subjects in most of the studies of Rourke and his colleagues were 9 to 14 years of age (e.g., Rourke and Finlayson 1978; Rourke and Strang 1978; Strang and Rourke 1983). Rourke (1989, p. 20) states that manifestations of learning disabilities in children aged 9 to 14 years are consistent with models of brain-behavior relationships in adults, but that manifestations in younger children tend to differ. Younger NLD children may have problems in the early stages of reading when right-brain skills are needed for analysis of visual differences. Rourke (1989, p. 68) believes that the early difficulties in reading are no longer noticeable by the time the visual-spatial abilities of such children are at a 6-to-7-year-old level (i.e., at approximately 9 to 10 years of age). For children in the first two school grades, arithmetic depends heavily on verbal memory for addition and subtraction facts, which is probably more a function of the left hemisphere than of the right. The spatial type of developmental dyscalculia, or arithmetic disability, does not generally become apparent until third or fourth grade when spatial arrays of digits become more complex. In the early grades, children who later have a spatial type of arithmetic disability may be thought to be visual dyslexics because of their slow progress in reading (Badian 1983). Weintraub and Mesulam (1983) suggest that there is a syndrome of early right hemispheric dysfunction that may be genetically determined and that is associated with introversion, poor social perception, chronic emotional difficulties, inability to display affect, and impairment in visuospatial representation. Cases of acquired right hemisphere lesions tend to have difficulty comprehending and expressing affectively intoned speech, comprehending and expressing emotional facial expressions (Heilman, Bowers, and Valenstein 1985), and in visuoperceptual skills (Benton 1985). Although one cannot conclude that the low nonverbal subjects of this study suffer from right hemispheric dysfunction, their poor visual-spatial ability (as shown by low scores on WISC-R Performance scale tests) and the poor social behavior of those low in reading are reminiscent of the characteristics associated with acquired right hemisphere lesions. Furthermore, the low nonverbal children referred for brain electrical activity mapping (BEAM) (Duffy and McAnulty 1985) have all shown abnormal right hemispheric or bilateral brain activity (Badian 1986).

NONVERBAl. LEARNING DISABILITY

175

That birth trauma may be of significance in the low nonverbal profile is suggested by the finding that 52 percent of the low nonverbal group, but only 6 percent of the low verbal group, had a history of low birth weight or of problems at the time of labor and/or delivery. We may be comparing a group with organic diffuse damage (low nonverbal) with a group whose poor verbal skills are genetically and/or environmentally determined (low verbal). The importance of early recognition of the NLD syndrome and of treatment of the disorder is highlighted by findings that children suffering from it are prone to depression and suicide as adolescents or adults (Rourke, Young, and Leenaars 1989). The present study suggests that a 6- or 7-year-old child who presents with significantly higher Verbal than Performance IQ has weaknesses on visual-motor integration tasks, such as form copying and handwriting, has poor social skills, and is making slow progress in reading, very probably suffers from the low nonverbal or NLD syndrome. Because school behavior and achievement may be affected by activity level, the groups of this study were compared on the WISC-R Freedom from Distractibility (FFD) factor and on earlier ratings of inattention and hyperactivity at the time of prekindergarten testing. The groups did not differ on the FFD factor and were similar in the percentages showing attention problems as prekindergarten children, and in taking stimulant medications for the attention deficit hyperactivity disorder later. The FFD factor has been shown by factor analyses to be distinct from the Verbal Comprehension and Perceptual Organization factors of the WISC-R, which closely approximate Verbal and Performance IQs (Kaufman 1979, p. 22). As its name suggests, the FFD factor is often interpreted as a measure of distractibility, short attention span, poor concentration, etc. However, as Kaufman (1979, p. 71) points out, it is possible that it may reflect a cognitive, rather than a behavioral, attribute.

Conclusions

There has been considerable research showing that children with learning disabilities are poorer in social adjustment than children without learning disabilities (e.g., Bender and Golden 1988; Gresham and Reschly 1986; Pearl, Donahue, and Bryan 1986), have greater difficulty interpreting social situations (Bruno 1981; Gerber and Zinkgraf 1982), and are less popular (Gresham and Reschly 1986; Hoyle and Serafica 1988; La Greca and Stone 1990). There have been many inconsistencies in these social behavior studies, however (See reviews of Dudley-

176

ORXCINS, ParrEaars, AND PROClVOSES

Marling and Edmiaston 1985, and Semrud-Clikeman and Hynd 1990). Semrud-Clikeman and Hynd point out that these studies vary widely in measures used, age of subjects, criteria for learning disabilities, and number of subjects. A further criticism of considerable importance is that the learning-disabled children were seen as constituting one group. A plea for greater specificity in research on learning disabilities, with more precise differentiation among subgroups of children, was voiced some years ago (Badian 1983). If this study had merely examined behavioral differences between good and poor readers, results would support those studies showing that children with a learning disability are poorer in social skills. However, the significant difference in social behavior between good and poor readers was found to be due only to the low nonverbal poor readers. Thus, variability between studies in proportions of subjects with low nonverbal and low verbal profiles may be a contributing factor in the inconsistent results of the research on social skills of learningdisabled children. Poor readers of this study who were low in Verbal IQ, in relation to Performance IQ, displayed no social behavior problems, and low motivation was the only behavior differentiating them from low verbal good readers. Poor nonverbal skills in relation to verbal and a probable right hemispheric dysfunction appear, at the minimum, to have an adverse effect on day-to-day organization and coping ability, contributing to lack of success in school. For the low nonverbal children who were good readers, this was their only disability, but those who were poor readers had social behavior deficits, in addition to the organization and coping problems. These children match more closely descriptions of cases of a nonverbal learning disability, or developmental disorder of the right hemisphere, except that they do not show a deficit in arithmetic, in relation to word recognition and spelling. It was pointed out that this difference from the usual findings was probably due to the young age of the children. Although most of them would meet criteria for dyslexia at this stage, it is probable that at 10-to-ll years of age the majority will no longer meet these criteria, but will present with a disability in mathematics, rather than in reading. As all children in the study had been referred for evaluation of possible learning problems, it is not clear to what extent the findings can be generalized to an unselected child population. However, in conclusion, this study suggests that children who appear to be dyslexic in the early school years and have low nonverbal ability, in relation to verbal, must be of the greatest concern to us all. These children are at much higher risk for social behavior problems and school failure, than poor readers with the low verbal/high nonverbal profile.

NONVERBAL LEARNING DISABILITY

177

References Badian, N. A. 1983. Dyscalculia and nonverbal disorders of learning. In H. R. Myklebust (ed.). Progress in Learning Disabilities, Vol. V. New York: Grune and Stratton. Badian, N. A. 1986. Nonverbal disorders of learning: The reverse of dyslexia? Annals of Dyslexia 36:253-269. Badian, N. A. and Ghublikian, M. 1983. The personal-social characteristics of children with poor mathematical computation skills. Journal of Learning Disabilities 16:154157. Bender, W. N. and Golden, L. B. 1988. Adaptive behavior of learning disabled and nonlearning disabled children. Learning Disabilities Quarterly 11:55-61. Benton, A. 1985. Visuoperceptual, visuospatial, and visuoconstructive disorders. In K. M. Heilman and E. Valenstein (eds.). Clinical Neuropsychology. New York: Oxford University Press. Brumback, R. A. and Staton, R. D. 1983. Learning disability and childhood depression. American Journal of Orthopsychiatry 53:269-281. Bruno, R. M. 1981. Interpretation of pictorially presented social situations by learning disabled and normal children. Journal of Learning Disabilities 14:350-352. Denckla, M. B. 1978. Minimal brain dysfunction. In J. S. Chall and A. E Mirksy (eds.). Education and the Brain. Chicago: University of Chicago Press. Dudley-Marling, C. C. and Edmiaston, R. 1985. Social status of learning disabled children and adolescents: A review. Learning Disabilities Quarterly 8:189-204. Duffy, E H. and McAnult~ G. B. 1985. Brain electrical activity mapping (BEAM): The search for a physiological signature of dyslexia. In E H. Duffy and N. Geschwind (eds.). Dyslexia: A Neuroscientific Approach to Clinical Evaluation. Boston: Little, Brown and Company. Gerber, P. J. and Zinkgraf, S. A. 1982. A comparative study of social-perceptualability in learning disabled and nonhandicapped students. Learning Disabilities Quarterly 5:374-378. Gresham, E M. and Reschly, D. J. 1986. Social skills deficits and low peer acceptance of mainstreamed learning disabled children. Learning Disabilities Quarterly 9:23-32. Heilman, K. M., Bowers, D., and Valenstein, E. 1985. Emotional disorders associated with neurological diseases. In K. M. Heilman and E. Valenstein (eds.). Clinical Neuropsychology. New York: Oxford University Press. Hoyle, S. G. and Serafica, E C. 1988. Peer status of children with and without learning disabilities--a multimethod study. Learning Disabilities Quarterly 11:322-332. Johnson, D. and Myklebust, H. 1967. Learning Disabilities: EducationalPrinciplesand Practices. New York: Grune and Stratton. Kaufman, A. S. 1979. Intelligent Testing with the WISC-R. New York: Wiley. Kaufman, A. S. and Kaufman, N. L. 1983. Kaufman Assessment Batteryfor Children. Circle Pines, Minnesota: American Guidance Service. Kaufman, A. S. and Kaufman, N. L. 1985. Kaufinan Testof EducationalAchievement. Circle Pines, Minnesota: American Guidance Service. La Greca, A. M. and Stone, IN. L. 1990. LD status and achievement: Confounding variables in the study of children's social status, self-esteem and behavioral functioning. Journal of Learning Disabilities 23:483-490. Myklebust, H. R. 1975. Nonverbal learning disabilities:Assessment and intervention. In H. R. Myklebust (ed.). Progress in Learning Disabilities, Vol. IlL New York: Grune and Stratton. Ozols, E. J. and Rourke, B. E 1985. Dimensions of social sensitivity in two types of learning-disabled children. In B. E Rourke (ed.). Neuropsychologyof Learning Disabilities. New York: Guilford Press.

178

OmGXNS, P,4vreeNs, AND PROGNOSES

Pearl, R., Donahue, M., and Bryan, T. 1986. Social relationships of learning-disabled children. In J. K. Torgesen and B. Y. L. Wong (eds.). Psychologicaland EducationalPerspectives on Learning Disabilities. San Diego: Academic Press. Rourke, B. E 1978. Reading, spelling, arithmetic disabilities: A neuropsychologic perspective. In H. R. Myklebust (ed.). Progress in Learning Disabilities, Vol. I. New York: Grune and Stratton. Rourke, B. P. 1982. Central processing deficiencies in children: Toward a developmental neuropsychological model. Journal of Clinical Neuropsychology 4:1-18. Rourke, B. P. 1988. Socio-emotional disturbances of learning disabled children. Journalof Consulting and Clinical Psychology56:801-810. Rourke, B. P. 1989. Nonverbal Learning Disabilities. New York: Guilford Press. Rourke, B. P., Bakker, D. J., Fisk, J. L., and Strang, J. D. 1983. Child Neuropsychology:An Introduction to Theory, Research, and Clinical Practice. New York: Guilford Press. Rourke, B. P. and Finlayson, M. A. J. 1978. Neuropsychological significance of variation in patterns of academic performance: Verbal and visual-spatial abilities. Journal of Abnormal Child Psychology 6:121-133. Rourke, B. P. and Fisk, J. L. 1981. Socio-emotional disturbances of learning disabled children: The role of central processing deficits. Bulletin of the Orton Society 31:77-88. Rourke, B. P. and Strang, J. D. 1978. Neuropsychological significance of variations in patterns of academic performance: Motor, psychomotor, and tactile-perceptual abilities. Journal of Pediatric Psychology3:62-66. Rourke, B. P. and Strang, J. D. 1983. Subtypes of reading and arithmetical disabilities. In M. Rutter (ed.). Developmental Neuropsychiatry. New York: Guilford Press. Rourke, B. P., Young, G. C., and Leenaars, A. A. 1989. A childhood learning disability that predisposes those afflicted to adolescent and adult depression and suicide risk. Journal of Learning Disabilities 22:169-175. Semrud-Clikeman, M. and Hynd, G. W. 1990. Right hemisphere dysfunction in nonverbal learning disabilities: Social, academic, and adaptive functioning in adults and children. PsychologicalBulletin 107:196-209. Stanovich, K. E. 1988. Explaining the difference between the dyslexic and the gardenvariety poor reader: The phonological-core variable-difference model. Journal of Learning Disabilities 21:590-604. St-rang, J. D. and Rourke, B. E 1983. Concept-formation/non-verbal reasoning abilities of children who exhibit specific academic problems with arithmetic. Journalof Clinical Child Psychology12:33-39. Strang, J. D. and Rourke, B. P. 1985. Adaptive behavior of children who exhibit specific arithmetic disabilities and associated neuropsychological abilities and deficits. In B. P. Rourke (ed.). Neuropsychology of Learning Disabilities. New York: Guilford Press. Tranel, D., Hall, L. E., Olson, S., and Tranel, N. N. 1987. Evidence for a right-hemisphere developmental learning disability. Developmental Neuropsychology 3:113127. Voeller, K. K. S. 1986. Right hemisphere deficit syndrome in children. American Journal of Psychiatry 143:1004-1009. Wechsler, D. 1963. WechslerPreschooland Primary Scale of Intelligence. New York: Psychological Corporation. Wechsler, D. 1974. WechslerIntelligence Scalefor Children-Revised. New York:Psychological Corporation. Wechsler, D. 1989. WechslerPreschooland Primary Scaleof lntelligence-Revised. San Antonio, Texas: Psychological Corporation. Weintraub, S. and Mesulam, M. M. 1983. Developmental learning disabilities of the right hemisphere: Emotional, interpersonal, and cognitive components. Archives of

Neurology 40:463-468.