Effects of methylphenidate on kinematic aspects of handwriting in hyperactive boys

Poor handwriting in hyperactive children often contributes to academic failure. Beneficial effects of methylphenidate on the quality of handwriting have been shown. Using a digitizing tablet, the handwriting of 21 hyperactive boys was examined both during methylphenidate treatment and following withdrawal of the drug. Half of the hyperactive boys were tested first on methylphenidate and then following withdrawal of the drug and the remaining hyperactive boys were examined in the reverse order. Twenty-one control boys underwent the same examination. Velocity and acceleration of handwriting movements were measured. Furthermore, every writing specimen was independently rated by four examiners regarding the quality of handwriting. Following withdrawal of the drug, the quality of handwriting specimens of hyperactive boys was poorer than during treatment with methylphenidate. Statistical comparison of writing movements of hyperactive boys on and off methylphenidate revealed that the medication resulted in a deterioration in handwriting fluency. The results showed that following withdrawal of medication, hyperactive children did not differ from control boys in handwriting movements. The improvement in hyperactive behavior through methylphenidate was associated with increased legibility and greater accuracy of handwriting. The intention to write neatly may interfere with the fluent writing process.     

Social judgment processes in hyperactive boys: Effects of methylphenidate and comparisons with normal peers

Although there is consensus that ADHD children have serious social problems, there is little understanding of the mechanisms underlying or accompanying such problems. To examine the possibility of atypical or faulty social reasoning, we presented ADHD and normal boys with a social perception task that entailed evaluating the behaviors of unknown peers. ADHD judges participated under both methylphenidate and placebo conditions, and on each occasion they evaluated an unfamiliar ADHD target in each medication state. In contrast to placebo, methylphenidate appeared to dampen overall response rates in ADHD judges, but there was no effect on sensitivity to medication-related differences. Regardless of their own medication state, ADHD judges identified more undesirable behaviors in peers on placebo than in those taking methylphenidate. Judges with the most serious behavior problems tended to identify the greatest number of negative behaviors in peers, especially when both judge and target were unmedicated. There were no effects of target medication status on detections of positive behaviors and few differences in detection patterns of ADHD versus normal judges. Discussion focused on the need to distinguish general regulatory from specific social-cognitive processes.This study was conducted at the Fernald Child Study Center, UCLA, and we very much appreciate the many contributions of Stephen P. Hinshaw, codirector of the program. We are also grateful to the resourceful and devoted staff and the energetic children who served as judges and targets.     

Effects of methylphenidate on inhibitory control in hyperactive children

This study investigated the effects of methylphenidate (MPH) on inhibitory control in hyperactive children. A double-blind, placebo-control, within-subject (crossover) design was used in which 12 children, between 6 and 11 years of age, were each tested four times in each drug condition: 0.3 mg/kg and 1.0 mg/kg of methylphenidate, and placebo. Dependent measures included (a) the probability of inhibiting responses to a primary choice reaction time task given a stop signal, on the Stopping Task, and (b) response latency and errors on the Matching Familiar Figures Test (MFFT). MPH improved the efficiency of the central inhibitory mechanism by speeding the inhibitory process, thereby affording the children greater control over their actions and enabling them to increase the probability with which they inhibited responses given a stop signal. MPH increased response latency but did not reduce errors on the MFFT, and observation of the children's task performance highlighted the interpretive problems associated with this task. Performance on both tasks was better at a dosage of 1.0 mg/kg than at 0.3 mg/kg.     

Prosocial behavior in hyperactive boys: Effects of stimulant medication and comparison with normal boys

To clarify the effects of stimulant medication on hyperactive (ADHD) children's prosocial as well as aversive behaviors toward peers, 19 hyperactive boys, aged 7–12, were observed as they acted as leaders for groups of 2–4 unfamiliar younger children. In a doubleblind crossover design, subjects were observed twice, once on placebo and again on a moderate (0.6 mg/kg) dose of methylphenidate (Ritalin). Thirteen comparison boys, without problems in attention and behavior, were also observed in the same leader roles. Relative to comparison boys, hyperactive boys on placebo were more socially engaged, used more aversive leadership techniques, and were rated as less likable by the younger children in their groups. Aversive social behaviors were the strongest predictors of being disliked by the younger children. No differences were found between comparison and unmedicated hyperactive boys for any aspect of prosocial behavior. Stimulant medication had a general dampening effect on social behavior, significantly reducing social engagement and increasing (mild) dysphoria relative to the placebo condition. The implications of these findings for understanding and treating the peer relationship difficulties of hyperactive children are discussed.This study was conducted at the Fernald Child Study Center, UCLA, and we very much appreciate the contributions of the many staff members of the program, especially those of Alice Huber-Dressler and Tracy Heller. We also are very grateful to staff and children of Corinne A. Seeds University Elementary School for their participation in this study.     

Self-control behavior in hyperactive and nonhyperactive children

This study was aimed at evaluating the self-control behaviors of hyperactive (HA) and nonhyperactive (NHA) first-grade pupils under conditions of repeated failure on a previously learned concept formation task. Subjects were divided into HA and NHA groups on the basis of their scores on the Conners (1969) Teacher Rating Scale. During the training stage of the experiment the children learned a concept formation task under a schedule of contingent positive reinforcement. In the test stage they performed the same task but under a negative noncontingent reinforcement schedule. The results revealed no differences in initial rate of learning the task between the groups. After the introduction of the negative noncontingent reinforcement schedule, however, the HA group showed a marked decrease in the use of effective problem-solving strategies. The HA children's performance on the concept formation task was accompanied by the emission of negative self-evaluations and solution-irrelevant statements. The NHA group used significantly more statements showing useful goal directed cognitive mediations than the HA children. The results suggested that HA children may have deficits in self-control skills.Grateful acknowledgment is made to the two anonymous reviewers whose insightful comments were very helpful in producing the final form of this paper.     

Motor timing deficits in community and clinical boys with hyperactive behavior: the effect of methylphenidate on motor timing

In a previous paper we showed that community children with hyperactive behavior were more inconsistent than controls in the temporal organization of their motor output. In this study we investigated: (1) various aspects of motor timing processes in 13 clinically diagnosed boys with attention deficit hyperactivity disorder (ADHD) who were compared to 11 community boys with hyperactive behavior and to a control group and (2) the effect of methylphenidate on the motor timing processes in the clinical group with ADHD in a double blind, cross-over, medication-placebo design, including 4 weeks of medication. The clinical group with ADHD, like the community group with hyperactivity, showed greater variability in sensorimotor synchronization and in sensorimotor anticipation relative to controls. The clinical group was also impaired in time perception, which was spared in the community group with hyperactivity. The persistent, but not the acute dose, of methylphenidate reduced the variability of sensorimotor synchronization and anticipation, but had no effect on time perception. This study shows that motor timing functions are impaired in both clinical and community children with hyperactivity. It is the first study to show the effectiveness of persistent administration of methylphenidate on deficits in motor timing in ADHD children and extends the use of methylphenidate from the domain of attentional and inhibitory functions to the domain of executive motor timing.     

Effects of methylphenidate (Ritalin) on information processing in hyperactive children

The effect of methylphenidate on information-processing efficiency was studied in 12 hyperactive, nonretarded children. Performance on six efficiency tasks (Posner Letter Matching, Reaction Time, Memory Search, Category Verification, Item Identification, and Word-Span) and a general measure of on-task behavior were compared for children receiving methylphenidate or a placebo. The median drug dosage was .38 mg/kg, and it was ingested 1 1/2 hours prior to testing. Children blind to the drug-placebo condition were tested on 4 days. In general, methylphenidate-related improvements in attention to on-task behaviors were found. An overall analysis of processing speed suggested that methylphenidate improved efficiency. Methylphenidate significantly decreased reaction times to simple and complex stimulus arrays; differences due to the drug remained even when on-task attentive behaviors were statistically removed. Significantly fewer identification errors occurred on the Posner task in the methylphenidate condition. Results indicated that methylphenidate improved general attentional behaviors and positively influenced processes that define perceptual efficiency.The first author was supported by NIH Training Grant No. HD 07184. We appreciate the assistance of Dr. Robert Sweeney in carrying out this research and the useful comments of Ellen B. Ryan and Jeanne D. Day.     

Span of apprehension in hyperactive boys

The spans of apprehension of hyperactive and normal boys were compared with a forced-choice letter-recognition task developed by Estes (1965). This task provides an estimate of the span which is relatively insensitive to either memory or motivational influences. The span size was the same for both groups when visual noise was absent. In the presence of noise, span size for the hyperactive boys decreased. Moreover, as the number of noise letters increased, the reduction in span size observed for the hyperactive boys increased. It is argued that this increasing reduction in span size represents a true deficit in attention.     

Effects of methylphenidate (Ritalin) on selective attention in hyperactive children

This study investigated the effect of methylphenidate (Ritalin) on the selective attention of hyperactive children designated as favorable or adverse responders to stimulant medication. Using a type II incidental learning paradigm, it was found that children in the drug condition recalled more central and less incidental stimuli than those children in the placebo condition. While no differential effects on recall were found for responder type, methylphenidate did affect the spontaneous overt labeling of central stimuli by the favorable responder group. Results were interpreted in terms of the role of methylphenidate in narrowing the focus of attention. Implications for the classification of hyperactive children as favorable and adverse responders were also discussed.This paper is based on a master's thesis completed by the first author in the Department of Psychology, University of Guelph, under the supervision of the second author. The authors wish to thank J. Thomas Dalby for his assistance in the conducting of this experiment.     

Attention and distractibility during reading in hyperactive boys

Nonhyperactive and clinically defined hyperactive boys were administered reading tasks under quiet and distracting conditions. Hyperactive boys were less attentive to task relevant stimuli and more attentive to task irrelevant stimuli than their controls. Our results demonstrate that the previous findings of inattentiveness among hyperactive boys on laboratory tasks can be generalized to more typical school activities such as reading.     

Effects of positive and negative feedback on behavior control in hyperactive and normal boys

The hypothesis that hyperactive boys have relatively less response to negative feedback than to positive feedback was studied. Sixteen hyperactive boys and 16 controls were compared on two tasks under different feedback conditions. Feedback conditions were no feedback, positive feedback, and negative feedback. Tasks were symbol encoding and correcting spelling words. Hyperactives and controls were compared in amount of time on-task and amount of work correctly completed. Hyperactives were on-task significantly more under conditions of negative feedback than under positive feedback, but negative feedback significantly increased errors on the spelling correction task. Controls were equally responsive to positive, negative, or no feedback. Hyperactives accomplished significantly less than controls on the coding task, but performed as well as controls on the spelling correction task, which was administered to each boy at his own level of spelling ability. The results imply that while consistent negative feedback can reduce off-task behavior for hyperactives, it can also decrease the accuracy of the work they are doing.This research was supported in part by U.S. Public Health Service Training Grant (in Biological Science) No. MH07081. This article is based on a dissertation presented to the Graduate School of Arts and Sciences of Washington University in partial fulfillment of the requirements for the Ph. D. degree. The assistance of Dr. John A. Stern in helping with the preparation of the dissertation is gratefully acknowledged. The generous assistance of Dr. Cynthia Janes in helping prepare this paper is appreciated. The dissertation is available from University Micro-films (Order No. 74-13, 799). The assistance of Ms. B. Talent and Ms. S. Weiner in making reliability checks is gratefully acknowledged.     

A psychosocial study of hyperactive and learning-disabled boys

Adequately reading hyperactive boys, normally behaved learning-disabled (LD) boys, and normal controls were contrasted on tests measuring personality traits, cognitive role taking, and moral reasoning. Additionally, parents and teachers rated all children on a number of behaviors, and parents were interviewed in a process-oriented fashion to assess home stimulation potential. Hyperactive boys were rated more aggressive and anxious than LD boys and controls and had not been encouraged as much by parents to achieve. Hyperactives had been born to younger parents, on the average, and 25% lived with their mothers and stepfathers. None of the LD or control boys had stepfathers. The groups did not differ significantly in moral reasoning ability, cognitive role taking, or locus of control; on the Junior Personality Inventory hyperactives tended to have elevated scores on the neuroticism scale while LD boys had higher scores on the lie scale.This research was supported by Grant HDNS-09119 from the National Institute of Child Health and Human Development.     

Perceptions of methylphenidate effects on hyperactive children's peer interactions

The behavioral constructs that emerge from observers' openended impressions of methylphenidate effects on the social behaviors of hyperactive children were examined. Ninety-six undergraduates observed videotapes of two different hyperactive target boys, each playing an interaction game with three peers. One target was taking methylphenidate and the other was taking placebo. The valence and content of observers' social perceptions were analyzed. Overall, more negative than positive behaviors were detected, a pattern more pronounced for the placebo than for the medication condition. Interestingly, placebo targets received negative evaluations for poorly controlled behaviors such as noncompliance, aggression, and disruption, but medicated targets received negative evaluations for social inhibition—passive and submissive behaviors. In contrast, the boys' medication state did not consistently influence observers' perceptions of positive social behaviors. Discussion focused on the extent and consequences of medicationrelated increases in social disengagement and on the ultimate impact of stimulant treatment on hyperactive children's social worlds.A preliminary report of this study was presented at the 1990 meeting of the Society for Research in Child and Adolescent Psychopathology, Costa Mesa, CA. We are grateful for the assistance of Pam Ajang, Keri Hom, and Scott Gutentag, and for support from the Fernald Child Study Center at UCLA.     

Effects of methylphenidate on the persistence of ADHD boys following failure experiences

We examined the effects of methylphenidate on the task persistence of 21 boys with attention-deficit hyperactivity disorder (ADHD), after they had been exposed to both solvable and insolvable problems. The boys attempted to solve 10 different find-a-word puzzles on each of 4 days, involving the crossing of medication (placebo vs. 0.3 mg/kg) and prior task difficulty (solvable vs. insolvable). The results revealed that medication prevented the decrement in performance following the insolvable problems that was evident with the placebo days. In addition, on medication compared with placebo, the boys were more likely to make external attributions for failure and internal attributions for success. The results are discussed in terms of the impact of medication on ADHD boys' performance as medicated by cognitivemotivational state mechanisms.This study was undertaken in the 1989 Summer Treatment Program conducted at Western Psychiatric Institute and Clinic. We thank the staff of the program for their cooperation, particularly Mary Vodde-Hamilton, Karen Greenslade, and Gary Vallano. The authors thank Monica Harris for her helpful comments.     

Overall nutrient intake of preschool hyperactive and normal boys

Studies examining the relationship between sugar intake of hyperactive children and behavior problems have reported inconsistent results. We hypothesized that if the problem behaviors of attention deficit-disordered children with hyperactivity (ADDH) are exacerbated by food, then this might be due to differences in their background nutrition relative to non-ADDH children. Parents and day care workers of 24 ADDH and 27 non-ADDH preschoolaged boys were trained to keep food diaries for 21 days. Analysis of the last 14 days for each child revealed no differences in overall nutrient intake between the two groups. On the other hand, for 5 ADDH and 3 non-ADDH children the within-subject correlations between daily behavior and sugar intake were significant. We concluded that nutrition-behavior interactions are more likely a function of idiosyncratic sensitivities, rather than a general tendency for ADDH children to eat differently from non-ADDH children.This research was funded by the Alberta Mental Health Research Advisory Council, and by the National Health Research and Development Program of Health and Welfare Canada. We think Jeannine Fraser for help with data analyses.     

Effects of experimenter and mother presence on the attentional performance and activity of hyperactive boys

The attentional performance, activity, and off-task behavior of hyperactive boys with and without conduct problems and normal boys were compared on a cancellation task under three conditions: when performing the task alone, with mother present, and with experimenter present. Results indicated that both the hyperactive groups achieved poorer attentional scores than normal subjects in the alone and mother present conditions, but improved in the experimenter present condition. The performance of the hyperactive boys with conduct problems was particularly affected by this condition. The activity and off-task behavior scores of both the hyperactive groups were higher than controls in all conditions, although the hyperactive boys with conduct problems decreased in off-task behavior when the experimenter was present. Attention and behavior scores were not significantly correlated. The implications of these findings for assessment of hyperactivity, and the role of noncompliance in the attentional behavior of hyperactive children, are discussed.This study is based in part on the first author's Ph.D. thesis in the Department of Psychology, University of Melbourne.     

Problem solving in hyperactive,normal, and reading-disabled boys

Diagnostic problem solving was examined in groups of hyperactive, normal, and nonhyperactive reading disabled boys matched on age and verbal IQ. On the matrix solution task employed (a version of the game of 20 Questions) hyperactives used less efficient questions and strategies than the other two groups, in spite of the task being designed to maximize the performance of the hyperactives. Readingdisabled children were not significantly worse than normal children on the task. The results were interpreted as suggesting that the attentional difficulties of hyperactives retard the development of strategies for solving complex problems. Nonhyperactive reading disabled children may be less affected in this area because of the absence of significant attentional difficulties.This article is based on a doctoral dissertation submitted to the Faculty of Graduate Studies and Research of McGill University by the first author. We are grateful to the students, teachers, and principals of the following schools in the Montreal area: Allancroft, Beacon Hill, Briarwood, Cedar Park, Greendale, Hillcrest, Lakeside Heights, Martinvale, Sunny Dale, Thomas H. Bowes, and Vivian Graham. Special thanks are due Rhonda Amsel, John MacNamara, and Chet Olsen for their help and advice.     

Social perspective-taking and teacher ratings of peer interaction in hyperactive boys

Hyperactive and matched control boys at two age levels were compared on teacher ratings of peer interaction and three measures of social perspective-taking. The teachers' ratings of peer interaction discriminated between the hyperactive children and their controls. In addition, a significant interaction effect indicated that teachers rated the older hyperactive group as more deviant with peers than both their younger hyperactive counterparts and their age-matched controls. In a structured laboratory setting, the hyperactive children did not differ from control children on the three measures of social perspective-taking. The perspective-taking measures did, however, show differences across age groups. Implications for treatment are examined.The research reported in this paper is based on master's thesis submitted to the Graduate Faculty of Arts and Sciences of the University of Pittsburgh by the first author. The authors are indebted to Dr. C. Keith Conners for his assistance in recruiting hyperactive subjects and to Drs. Alex Siegel and Carl Barenboim for their critical evaluations regarding this investigation. Appreciation is expressed to the staff, teachers, parents, and students of the Forest Grove Elementary School for their cooperation.     

The assessment of impulsivity and mediating behaviors in hyperactive and nonhyperactive boys

Twenty boys (6–8 years) rated by their teachers as hyperactive and a matched sample of nonhyperactive boys performed a task that required them to withhold responding for a set time interval in order to be rewarded (DRL 6-second schedule). Half of each group worked on a one-button console while the other half was provided with additional collateral buttons. Results indicated that hyperactive children were relatively unable to perform efficiently on the task, and that this deficit endured regardless of age, IQ, or experimental condition. DRL was thus found to discriminate accurately between teacher-rated and parent-rated hyperactive and nonhyperactive children. Furthermore, a wide variety of self-generated mediating behaviors was observed, and it was determined that a child's DRL performance was related to the kind of mediating behaviors he displayed. Results are discussed in terms of the clinical assessment of hyperactivity and the training of impulsive children.This report is based upon a dissertation submitted by the author in partial fulfillment for the Ph.D. degree. The efforts of Malcolm Helper, David Hothersall, Donald R. Meyer, Marilyn Moody, and Charles Wenar are gratefully acknowledged. The investigation was conducted while the author was a National Research Fellow, supported by Public Health Service Training Grant No. 5 T32 MH14608-02 to The Ohio State University.     

Types of private speech produced by hyperactive and nonhyperactive boys

Types and amount of private speech (audible talking that is not addressed to another person) were assessed during the free play of 16 hyperactive and 16 nonhyperactive boys. Verbalizations were coded into nine categories that denoted the boys' level of use of verbal control of their own behavior (Luria, 1961; Kohlberg, Yeager, & Hjertholm; 1968). Differences in amount and type of private speech between hyperactive and nonhyperactive boys were found to indicate that hyperactive boys may be presenting a specific or general cognitive lag in development. Treatment ramifications are discussed.