ADDH Children Research Articles

Event-related brain potentials in children with attention-deficit and hyperactivity disorder: Effects of stimulus deviancy and task relevance in the visual and auditory modality

It has frequently been reported that in so-called oddball tasks, children with attention-deficit and hyperactivity disorder (ADDH) show small P3 peaks of the event-related potential (ERP) in response to "targets" (task-relevant deviant stimuli) than normal children. It is not clear, however, whether this smaller P3 is due to abnormal processing of infrequent stimuli per se and/or of task-relevant stimuli and whether it is preceded by abnormalities in earlier peaks, especially those thought to be related to automatic deviancy detection [mismatch negativity (MMN) in the auditory modality and P2N2 in the visual modality]. ERPs of ADDH and normal children in response to visual and auditory stimuli were studied in a condition without task relevance as well as in a task-relevant condition. ADDH children showed smaller P3 amplitudes and (marginally) smaller MMN to auditory deviant stimuli, irrespective of task relevance, so smaller P3s in ADDH children are due to stimulus deviancy per se. In the visual modality the P3 effect failed to reach significance. Because the smaller P3s were also found in a condition not requiring task-related motivation, recent motivational interpretations of differences with normal children are not supported. ADDH children also showed smaller P1 amplitudes than normal children to all stimuli except visual novels. The ERP differences were unrelated to performance, since both groups performed equally well.

Auditory event-related brain potentials in autistic children and three different control groups

ERPs to auditory stimuli, generated during an oddball task, were obtained in a group of autistic children and three control groups (normal, ADDH, and dyslectic children, respectively). The task included the presentation of standards, deviants, and novels and had a (between-group) passive vs. active (counting) condition. It was examined whether 1) it was possible to replicate several earlier findings, 2) autistics manifest an abnormal lateralization pattern of ERPs, 3) autistics have an abnormal mismatch negativity (MMN), and 4) differences between autistics and normals are really specific to the autistic group. The only finding that could be replicated was that autistics have a smaller A/Pcz/300. There was no evidence for abnormal lateralization or abnormal MMN; however, there was an unexpected effect of the task manipulation on the amplitude of the P3: in autistics, the occipital P3 to deviant stimuli was significantly larger in the active than in the passive condition, a finding, like the replication of the smaller A/Pcz/300, specific to the autistic group. It was suggested that the auditory occipital task effect is related to understimulation of the occipital lobe by visual stimuli in autistic children.

Coincidence of attention deficit disorder and atopic disorders in children: Empirical findings and hypothetical background

ADDH children are often reported to display signs of allergies to various substances and/or atopic (AT) symptoms (i.e., atopic eczema, hay fever, or asthma). Since, at least for a subgroup of these children, a common biological background for both ADD and atopy may be assumed that may involve brain catecholamines, our hypothesis was that in a group of AT children (mainly atopic eczema) signs of ADD should appear more often than in controls. Parental hyperactivity ratings revealed a significantly higher frequency of ADD symptoms in the AT group, and laboratory tests sensitive to attentional capacity and inhibitory functions showed poorer performance in the AT children, the findings being similar to those reported in hyperactives. Thus, our results add support to the assumption of a common predisposing factor for both AT and ADDH in a subgroup of children.

The Effects of Reinforcement and Response–Cost on a Delayed Response Task in Children with Attention Deficit Hyperactivity Disorder: A Research Note

Children with attention deficit hyperactivity disorder are more inattentive, active, and impulsive than normal children. Some researchers have postulated that these symptoms can all be explained as a result of reduced sensitivity to reinforcement. In order to evaluate this hypothesis, we tested 20 ADD-H children and 18 matched normal controls, 4 1/2-11 years of age, on a delayed response task, a measure of impulsiveness, under conditions of positive reinforcement, and punishment in the form of response-cost. The contingencies each improved performance compared to baseline but did not differ significantly from each other. Neither contingency affected the groups differentially, thus failing to provide support for the reinforcement hypothesis.

Methylphenidate: Emergent symptom profile of dose-reponse effects in ADDH children

Methylphenidate: Emergent symptom profile of dose-reponse effects in ADDH children

Comprehensive evaluation of attention deficit disorder with and without hyperactivity as defined by research criteria.

Children with attention deficit disorder with hyperactivity (ADD+H; N = 48) were compared with those without hyperactivity (ADD-H; N = 42), as well as with learning disabled and control children, on an extensive battery of interviews, behavior ratings, tests, and direct observations. ADD+H children had more externalizing and internalizing symptoms by parent and teacher report, were more off task during vigilance testing, and had more substance abuse, ADD+H, and aggression among their relatives than did the other groups. ADD-H children were more day-dreamy and lethargic by teacher report, more impaired in perceptual-motor speed, and had more anxiety disorders among their relatives than did ADD+H children. Results indicate that these 2 types of ADD may be separate, distinct childhood disorders rather than subtypes of a common attention deficit.

Does Methylphenidate Constrict Cognitive Functioning?

It has been suggested that stimulants enhance attention in children with (attention deficit disorder with hyperactivity) (ADDH) by producing a generalized constriction or “over-focusing.” Such a phenomenon might be expected to adversely affect performance on tasks, such as those in the Wallach-Kogan (W-K) battery, which explicitly call for cognitive flexibility or “divergent thinking.” Nineteen ADDH children, 6 to 10 years of age, were tested on two modified subtests of the W-K battery at baseline, following placebo, and following three different dosages (.3, .6 and 1.0 mg/kg) of methylphenidate. Contrary to the hypothesis, methylphenidate did not decrease but rather sustained output on the tests, which contrasted with a decline in productivity seen across nondrug days. Some ADDH subjects displayed particularly large increases in output following methylphenidate and may represent an atypical subgroup of children who became overaroused on medication.

Cognitive training in academically deficient ADDH boys receiving stimulant medication.

This study evaluated the effectiveness of a 16-week intensive cognitive training program in stimulant-treated, academically deficient ADDH boys. Cognitive training focused exclusively on academic skills and tasks, and included attack strategy training as well as self-monitoring and self-reinforcement of problem-solving behaviors and response accuracy. Control groups included remedial tutoring plus medication, and medication alone. Despite the scope of the program, the results provided no support for the notion that academically based cognitive training ameliorates the performance and achievement of academically deficient ADDH youngsters. Further, this intervention did not enhance self-esteem or attributional perceptions of academic functioning. There was poor agreement between teacher ratings of academic competence and test score changes. The lack of concordance between measures, and the scarcity of academically deficient ADDH children are discussed.

Self-regulation of stimulation for ADD-H children during reading and vigilance task performance.

The present study examines the hypothesis that motor responses added into rote tasks would modulate the sensation-seeking activity and impulsive errors of hyperactive (ADD-H) children. To this purpose 22 ADD-H and 25 comparison children were administered two repetitive tasks (word decoding and an auditory vigilance task) under both an active response and a passive response condition. Findings were that the impulsive errors, talking/noisemaking, and activity of ADD-H children was normalized (i.e., did not differ from comparison children) only in the high stimulation active response conditions. Behavioral improvements for ADD-H children were documented in both tasks in the active condition, but performance gains were found only in the vigilance task. The findings supported predictions derived from the optimal stimulation theory that the excessive activity and attraction to novel stimuli of ADD-H children can be channeled into appropriate instrumental motor and attention responses.

Peer interactions of normal and attention-deficit-disordered boys during free-play, cooperative task, and simulated classroom situations.

Groups of 30 ADD-H boys and 90 normal boys were divided into 30 mixed dyads composed of a normal and an ADD-H boy, and 30 normal dyads composed of 2 normal boys. Dyads were videotaped interacting in 15-minute free-play, 15-minute cooperative task, and 15-minute simulated classroom settings. Mixed dyads engaged in more controlling interaction than normal dyads in both free-play and simulated classroom settings. In the simulated classroom, mixed dyads completed fewer math problems and were less compliant with the commands of peers. ADD-H children spent less simulated classroom time on task and scored lower on drawing tasks than normal peers. Older dyads proved less controlling, more compliant with peer commands, more inclined to play and work independently, less active, and more likely to remain on task during the cooperative task and simulated classroom settings. Results suggest that the ADD-H child prompts a more controlling, less cooperative pattern of responses from normal peers.

Behavorial Parent Training and Cognitive-Behavioral Self-Control Therapy With ADD-H Children: Comparative and Combined Effects

We assessed the effects of behavioral parent training and cognitive-behavioral self-control therapy with 24 elementary school-age children diagnosed as having attention deficit disorder with hyperactivity. A randomized-group design with repeated measures and multiple outcome criteria was employed comparing behavioral parent training alone, self-control instruction alone, and a combination of the two treatments. All groups showed significant improvement over time, but the only significant Treatment Group x Time interaction reflected a greater decrease in hyperactivity scores at follow-up for children in the self-control instruction alone group. Furthermore, although there was significant maintenance of change at 1-month follow-up, there was no evidence for generalization of change to the classroom. Stepwise multiple-regression analysis showed that mothers with greater perceived extrafamilial and community social support, and children who were better able to reflect on problems, who admitted to greater self-control problems, and who had a more internal locus of control, evidenced greatest behavioral improvements.

The normalizing effects of methylphenidate on the classroom behavior of ADDH children.

This study examined whether methylphenidate normalizes the behavior of hyperactive children (ADDH). Twenty-eight ADDH children were treated for 8 weeks with a mean dose of 41.5 mg/d of methylphenidate. Their classroom behavior and that of normal children was recorded by observers who were blind to diagnosis and treatment. Before treatment, all measures significantly differentiated the ADDH and normal children. After treatment, the two groups were indistinguishable on measures of gross and minor motor movement, noncompliance, interference, and overall hyperactivity. ADDH children were significantly improved on measures of attention but continued to be significantly less attentive. In many ways, the ADDH children were not only improved but indistinguishable from their normal peers.

Peer relationships in ADDH and normal children: a developmental analysis of peer and teacher ratings.

Peer and teacher perceptions of younger and older ADDH and normal children were compared. Peer nominations on the Pupil Evaluation Inventory revealed that ADDH children received more nominations on the Aggression factor and fewer on the Likability factor. ADDH boys received more nominations on the Withdrawal factor. Generally, older children received fewer nominations, but age did not interact with diagnosis; that is, younger and older ADDH children were perceived by peers as equally deviant. Discriminant analyses showed that peer ratings were useful in discriminating between ADDH and normal boys, but not between ADDH and normal girls. Teacher ratings of peer behavior suggested that older ADDH girls were perceived as less disturbed than younger girls. However, teacher ratings of boys revealed no age by diagnosis interactions. Low to moderate correlations were found between peer and teacher ratings of ADDH boys, and the pattern of relationship varied with age.