Visual perseveration in normal and mentally retarded children

Visual perseveration was investigated within mentally retarded and second, fifth, and eighth grade normal children (Ns = 12 each group). Subjects matched an auditorially presented click to the onset and offset of visually presented stimuli. Time differences between visual stimulus offset and the point at which subjects reported simultaneity of the click and visual stimulus offset was assumed to reflect visual perseveration. Results showed: (a) no differences between the normal children as a function of age; (b) no difference between groups for stimuli of 100 msec. or longer duration; and (c) retarded subjects judged stimuli of 20 and 50 msec. to be of shorter duration than did normal subjects. This highly specific distinction between retarded and normal subjects suggests a difference in an early stage of perceptual processing.     

A follow-up developmental study of hypothesis behavior among mentally retarded and nonretarded children

To clarify the roles of IQ and mental age (MA) in hypothesis behavior, MA-matched subjects at three levels of IQ (70, 100, and 130) and three levels of MA ($\text{5}\text{1}\text{2}\text{, 7}\text{1}\text{2}\text{,}\text{and}\text{9}\text{1}\text{2}\text{years}$) received blank-trial discrimination learning problems using procedures designed to discourage position-oriented responding. With position responding discouraged, earlier findings were contradicted in that no hypothesis measure showed a main effect of IQ. This suggest that previously reported IQ group differences in hypothesis behavior may not reflect cognitive deficits inherently linked to low IQ, but instead may reflect the influence of specific methodological factors. The finding and interpretation are consistent with Zigler's (American Journal of Mental Deficiency, 1969, 73, 536–556) “developmental” theory of retardation and inconsistent with the general “difference” position. In additional findings, the predictions that subjects at all three MA levels would use hypotheses, and that retarded children from special-education classes would use hypotheses more often than retarded children “mainstreamed” in classes for the nonretarded were confirmed.     

Patterns of imitation in mentally retarded children

Abstract.— In this report, the interchange theory of imitation was extended to mentally retarded children. Retardates were expected to observe and copy adults, using external cues and internal controls as aids. In Experiment I external cues were studied. Twenty-four speaking and 24 non-speaking retardates were paired with adults who gave half the children instructions to copy and the other half additional verbal and gestural cues. Non-speaking retardates receiving frequent cues attended and copied better than those getting initial instructions, gestural cues being equally or more effective than verbal ones. Speaking retardates getting repeated cues finished copying sooner than those getting only instructions, verbal and gestural cues being equally effective. In Experiment II internal controls over appropriate imitation were studied. Twenty-two retardates were trained to sit, observe and copy their teachers in a two-month program. Training was evaluated in situations where copying or playing was signalled. Overall, children attended and copied more in the appropriate situation. However, sitting, attention, and copying increased non-specifically in both situations, and initial situational differences in copying were not observed after treatment. The interchange theory was revised, and implications for attention-deficit and verbal self-control theories were discussed. Notions of "generalized imitation" were criticized.     

Self-concept in educable mentally retarded and emotionally handicapped children

A total of 48 educable mentally retarded (EMR) and emotionally handicapped (EH) children ( \(\overline {CA} \) =137.7 months) were pretested on Coopersmith's Self-Esteem Inventory (SEI), Nowicki-Strickland's Locus of Control Scale for Children (LCSC), and 3 behavioral measures: (1) risk-taking, (2) a chance/skill task, and (3) delay of gratification. One group of 12 children from each population was then exposed to either a self-confident or a control model. After exposure, Ss were given an opportunity to perform successfully on an ambiguous task and answer questions about their success, and were readministered the SEI, LCSC, and 3 behavioral choices. Correlational analyses of pretreatment data revealed significant relationships between defensiveness and LCSC, SEI, and delay of gratification and a near-significant relationship between LCSC and SEI. EMR and EH Ss were both lower on self-esteem than the general population, while EMR Ss were more defensive, more external, and less likely to delay gratification than EH Ss. Both treated groups matched more of the behavioral choices than the control groups, while only treated EH Ss were more likely to attribute their success to internal causes. It was concluded that EMR and EH children differ in self-concept development and that future attempts to modify self-concept should include greater modeling exposure as well as increased opportunity for performance with its resultant feedback.     

Developmental differences in reactions to children labeled mentally retarded

In an attempt to examine age-related differences in response to the mental retardation label, 48 4th and 5th graders and 48 11th and 12th graders were told of a child of their own age and sex who was either labeled mentally retarded or unlabeled and who performed either competently or incompetently in giving a report. Incompetent target children were viewed more negatively than competent ones at both grade levels. The mental retardation label had less generalized impacts, leading girls but not boys (a) to cite lack of ability as the reason for a retarded child's failure, and (b) to hold low expectations that retarded targets would hold jobs, marry, or have children. A developmental shift in responses to the label was evident only on a trait perception measure; younger children stigmatized retarded targets, while older children granted special dispensation of a failing retarded child by viewing him or her more positively than a similarly incompetent but unlabeled child. Since only adolescent boys showed special dispensation, even though girls were more generally attentive to the label, both sex and age differences warrant further examination.     

Hierarchical semantic organization in educable mentally retarded children.

Fifty-four educable mentally retarded (EMR) children looked at eight familiar pictures. Subsequently they attempted to recall each picture when given as retrieval cues the corresponding noun and four other words that represented a hierarchical class inclusion system for that particular picture. Five predictions based on a model of semantic distance in the structure were tested. Four of the predictions were significantly confirmed. Thus, EMR children showed evidence of functional use of a hierarchical class inclusion system in memory retrieval. These results are not suggested by most of the relevant literature in mental retardation.     

Heart-rate variability during nocturnal sleep in mentally retarded children.

Heart-rate variability in four normal and 30 mentally retarded children was investigated during nocturnal sleep. In four normal and 25 mentally retarded subjects, a high frequency component defined as spectral activity between 0.15 and 0.5 Hz was found in the compressed spectral array of the power spectra. A periodic change was seen in the high frequency component which corresponded precisely to the sleep cycle. However, four children with mental retardation did not show normally expected changes in the high frequency components specific to the sleep stages: a quantity of the high frequency component in only one sleep cycle (n=2; 6 mo. and 3 yr., 8 mo.), a decreased quantity and discontinuity of the high frequency component in only the second sleep cycle (n=1; 1 yr., 2 mo.), and no high frequency component in any sleep cycle (n=1; 3 mo.) These findings suggest that some mentally retarded children have an abnormal parasympathetic nervous activity.     

Training interpersonal skills among mentally retarded and socially dysfunctional children

Two moderately retarded boys, ages 11 and 12 yr, who resided in an inpatient unit for emotionally disturbed children, were treated for deficits in social skills. The deficits included physical gestures, facial mannerisms, eye contact, words spoken, and intonation and content of speech. The treatment package consisted of instructions, performance feedback, social reinforcement, modeling, and role-playing. The effects of the treatment in developing appropriate social performance were evaluated in separate multiple-baseline designs across behaviors for each child. The training improved social skills and brought children up to or beyond the level of normal control subjects who were the same age and gender.     

Control in memory for movement cues by mentally retarded children

The study was designed to determine the desirability of providing external prompts (1) to use a mnemonic to enhance accuracy of recall and (2) to use response 'priming' in memory for spatial location by mentally retarded persons. Two groups of 40 mentally retarded boys and girls and two groups of 40 MA-matched nonretarded children were compared for accuracy in the recall of movement on an arm-positioning task. No differences were found between mentally retarded subjects and MA-matched subjects treated under the same conditions. However, all groups were unable to make spontaneous control adjustments to accommodate the covert manipulations made just prior to recall. By providing response primes, appropriate performance adjustments were made by all groups, resulting in a significant improvement in accuracy of recall. These findings serve to reaffirm earlier reports showing remarkable similarity between the mentally retarded and MA-matched nonretarded subjects.     

Selected parameters of response organization in mildly mentally retarded children

The purpose of this study was to investigate the effect of response organization on reaction time (RT) and movement time (MT) of mildly mentally retarded children. Two groups of 30 subjects each were formed: a retarded group 9 yr. of age and a normal group matched for chronological age. Subjects were randomly assigned to one of three precued conditions in which they were told that the forthcoming response would be performed with the right or left hand (precue hand), be to the right or left side (precue direction), or cross or not cross the body midline (precue midline). The retarded group performed significantly more slowly than the normal group on both RT and MT. Both groups, however, were able to utilize precued hand information as opposed to other precued variables, indicating that knowing which hand to use is important when organizing responses.     

Social problem solving and mother-child interactions of educable mentally retarded children

Mothers of retarded children and nonretarded children were observed and videotaped as they interacted with their own child in a seminaturalistic situation, requiring teaching, cooperation, and free play. The child's social problem-solving abilities were assessed independently. The Vineland scale was employed to provide some convergent evidence of social problem-solving as a component of social competence. Twelve educable mentally retarded and 19 nonretarded 10-year-old children and their mothers comprised the sample. For the mentally retarded group, it was found that the higher maternal directiveness, the lower the child's social problem-solving skills. Mothers who often gave the child opportunity for decision-making and social influence had children with higher problem-solving skills. The retarded children produced significantly fewer different strategies for solving social problems, but gave a wider range of strategies than has been found in previous research. There was some support that social problem-solving skills are related to social maturity.