Tactile stimulation and interhemispheric communication by learning disabled children: an exploratory study

33 right-handed, learning disabled children aged 8-10 yr., 11-13 yr., and 14-16 yr. were presented a tactile discrimination task. Pairs of fabrics of different or the same texture were presented to the same hand (uncrossed condition) or alternating hands (crossed condition). Analysis indicated that the total number of crossed errors was significantly greater for the youngest children. There were no significant differences between the groups for the uncrossed condition. These results suggest that younger learning disabled children may experience greater difficulty on a task which required interhemispheric transfer.     

Tactile discrimination of shape by octopus

Experiments are described showing that Octopus can be trained to distinguish by touch between a cube and a sphere, a surprising result since previous work has always indicated that octopuses cannot take proprioceptive information into account in learning. It can be shown, however, that the cube/sphere discrimination is made by detecting the distortion imposed on the rims of individual suckers in contact with the corners of the cube. Thus it is shown (1) that a cube with the corners even slightly rounded is less readily distinguishable from a sphere than a cube with sharp corners and, more important, (2) that a narrow rod is readily accepted in place of the cube by trained animals. Indeed, the rod seems to be a “better” cube than the original, and errors of discrimination decrease when it replaces the cube, presumably because it lacks flat surfaces liable to be confused with the surface of the sphere by a system depending on information from sense organs arranged in circles on the rims of the suckers.     

Naming of object-drawings by dyslexic and other learning disabled children

On the Oldfield-Wingfield Picture-Naming Test, sensitive to subtle chronic dysphasia in adults, dyslexic children name fewer pictures correctly. Even when correct on words with less than 30 per million frequency of occurrence, they perform more slowly than do nondyslexic subjects suffering from minimal brain dysfunction (MBD) or normal controls. However, there is no evidence for “perceptual impairment” underlying dyslexic subjects' low scores and prolonged latencies, as the distribution of their errors is similar to that of normal children. Rather it is the nondyslexic MBD group which produces a high percentage of wrong names, suggestive of mistaking the pictured stimuli for other, visually similar, objects.     

Reading deficits in learning disabled children

The purpose of this study was to determine whether LD children exhibited problems in the processes of attention, memory, or syntactical awareness when decoding written prose. Eighteen LD children and 18 normal controls were matched for initial word recognition skills. Subjects were then trained to read a list of individual words to criterion. Subsequently, they were tested on their ability to decode the same words in paragraph form, presented both immediately after training, and then again one week later. Half the children read paragraphs following standard English syntax, while the other half read a syntactically scrambled version of the same paragraph. The results indicated that a major contributing factor in the reading (decoding) difficulties demonstrated by the LD children derived from problems of acquisition and retrieval from long-term memory storage. The results were discussed in terms of their implications for the developmental lag theory of learning disabilities.     

Concurrent verbal and emotion laterality effects exhibited by normally achieving and learning disabled children.

This study assessed both left- and right-hemisphere functions simultaneously when two-syllable words differing only in the initial stop consonant and spoken in different emotional tones were paired dichotically. Seventy-two right-handed normally achieving children, 12 boys and 12 girls at each of grades 1, 3, and 5, were instructed to detect either the presence of a specific word or of a specific emotion. In addition, 30 right-handed learning disabled (LD) children (age-matched to the normal controls) were assessed to determine whether LD children distribute verbal and nonverbal functions to different hemispheres. Results indicated that although both control and LD children demonstrated an overall REA for word stimuli and an LEA for emotional stimuli, and that emotional stimuli were easier to process than word stimuli, LD children were less accurate in processing both types of stimuli than their control counterparts. 'Complementary specialization,' as assessed through distribution of laterality effects, was found to be greater for control children than for LD children. However, the lack of consistency in complementary specialization found among the three developmental grade levels may be indicative that independent brain mechanisms underlying verbal and emotional processing have yet to be fully established in children. Further, in contrast to adult findings, a larger LEA was obtained for the emotion 'happy' than for the emotion 'sad.' It was concluded that whereas independent hemisphere processing for words and emotions is somewhat prevalent for control children, LD children might not be as strongly lateralized for opposite hemisphere processing of these functions.     

Vision and academic performance of learning disabled children

The purpose of this study was to assess difference in academic performance among myopic, hyperopic, and emmetropic children who were learning disabled. More specifically, myopic children were expected to perform better on mathematical and spatial tasks than would hyperopic ones and that hyperopic and emmetropic children would perform better on verbal measures than would myopic ones. For 439 learning disabled students visual anomalies were determined via a Generated Retinal Reflex Image Screening System. Test data were obtained from school files. Partial support for the hypothesis was obtained. Myopic learning disabled children outperformed hyperopic and emmetropic children on the Key Math test. Myopic children scored better than hyperopic children on the WRAT Reading subtest and on the Durrell Analysis of Reading Difficulty Oral Reading Comprehension, Oral Rate, Flashword, and Spelling subtests, and on the Key Math Measurement and Total Scores. Severity of refractive error significantly affected the Wechsler Intelligence Scale for Children--Revised Full Scale, Performance Scale, Verbal Scale, and Digit Span scores but did not affect any academic test scores. Several other findings were also reported. Those with nonametropic problems scored higher than those without problems on the Key Math Time subtest. Implications supportive of the theories of Benbow and Benbow and Geschwind and Behan were stated.     

Dynamic balance of learning disabled and nondisabled children

This investigation assessed a difference in the dynamic balance abilities of 30 learning disabled and 30 nondisabled children of elementary-school age. Only distance traveled across the beam, a novel task, was significantly different between groups; no other effects were significant. Nondisabled subjects traveled further across the beam before losing balance than learning disabled children.     

Visual feature integration in learning disabled children

This study examined the ability of 7 learning disabled children to detect and integrate visual features in a complex display. While the learning disabled children performed more poorly over-all than 6 control children, differences between the two groups were most pronounced when subjects were required to conjoin or integrate visual features to make a decision about the presence of a target item. This finding is discussed with reference to automatic and attention-demanding components of visual perception.     

Syntactic decoding times of learning disabled children

Syntactic decoding reaction times of 20 learning disabled children comprising two groups of subjects (mean age of 8 and 13 yr., respectively) were compared to the responses of normal controls matched for age and sex. An analysis of variance procedure showed that the learning disabled children and their normal peers did not differ significantly in responses to the experimental stimuli. This held true regardless of linguistic complexity, suggesting that delays in processing elementary syntactic constructions are not a concomitant of learning disabilities.     

Three experiences affecting spatial discrimination learning by ambulatory children

Children 1 and 3 years of age were given a two-choice spatial discrimination task. They were placed in front of a barrier and encouraged to walk around it; one route around the barrier was blocked. Three experiments studied the effects of different types of experience with this spatial problem. The first examined trial and error experience, in which the child was allowed to walk the route he or she had chosen. Although most children readily learned to choose the open route, the pattern of choices indicated that 3-year-olds were more likely to achieve a learning criterion after an error than 1-year-olds. A second experiment looked at the effects of showing the children the layout of the problem prior to trial and error experience. The 3-year-olds were again more likely than the 1-year-olds to achieve criterion after an error; furthermore, they were likely to know the correct route on the first trial. The third experiment let the children watch their parents take the correct route. This procedure eliminated age differences in performance. The initial choices of the 1-year-olds indicated that they were likely to know the correct route, and if they did not, they were just as likely to learn from their mistakes as the 3-year-olds. The data were interpreted within a mathematical model of learning. Based upon these analyses, we propose two developmental trends. One involves a growth in sensitivity to the consequences of a choice of route. The other is a progression from social learning to more independent and ideational methods of spatial problem solving.     

Variations in WISC-R patterns of learning disabled children

The WISC-R was administered to 19 learning disabled students at the time of diagnosis and following a period of time in special program placements. Group analyses indicated fluctuations between testing times in the Verbal and Full-Scale IQs and the V-P IQ discrepancies. Small but significant differences in Verbal, Performance and V-P scatter indices were observed at one or both testings in comparison to the normal standardization sample. Although the suggested group pattern for learning disabled children based on the Bannatyne categories was confirmed on both occasions, there was considerable variation for individual subjects.     

Television viewing habits of emotionally disturbed,learning disabled,and mentally retarded children

Two studies were conducted to compare the television viewing habits of handicapped and nonhandicapped children. In Study 1, one group (N = 38) of emotionally disturbed (ED), learning disabled (LD), and educable mentally retarded (EMR) children and two groups of matched controls comprised of nonhandicapped peers were interviewed about their television viewing habits. In Study 2, 42 ED boys and 42 non-ED boys completed a television program diary. The studies found that handicapped children watch more television overall and more aggression-laden programs (i.e., crime dramas and cartoons) than nonhandicapped children. The potential impact of viewing television aggression on the behavior of handicapped children is discussed.     

Hyperactivity and related behavioral characteristics in a sample of learning disabled children.

64 learning disabled and 12 minimal brain-damaged children were evaluated by their teachers on 11 categories of behavior. Analysis showed that behavioral characteristics associated with hyperactivity did not differentiate among subjects. Teachers rated poor motor coordination as the outstanding trait of this sample.     

Motor and cognitive proficiency of learning disabled and normal children

Motor and cognitive skills of learning disabled (N = 32) and normal (N = 32) boys were compared on the Modified Lincoln-Oseretsky Motor Development Scale and on the WISC-R Vocabulary and Block Design subtests. Eight learning disabled and eight normal boys were tested at four age levels from 8 to 11 years. All boys were of normal intelligence. Motor and cognitive skills of the learning disabled boys were significantly below those of the normal boys and below those of the normative group. Chronological age was not a significant factor in relationship to either motor or cognitive skills. Intercorrelations indicated that in the learning disabled group Block Design, but not Vocabulary, was significantly related to motor scores at the 8- and 9-year ages. These results suggest that a common factor relating to perceptual-motor coordination and efficiency may be involved on the Lincoln-Oseretsky and Block Design subtest for young learning disabled children but not for older learning disabled children or for normal children.