Do hyperactive children and their siblings differ in IQ and academic achievement?

To test the hypothesis that intellectual deficits are traits shared by family members of hyperactive children, 18 hyperactive children were compared to their nonhyperactive siblings on measures of intellegence and academic achievement. As measured by the Wechsler Intellegence Scale for Children, the nonhyperactive siblings had significantly higher Verbal, Performance, and Full Scale IQs. Scores on the Wide Range Achievement Test and the Gray Oral Reading Test did not differ between the groups when adjusted for IQ. Contrary to previous hypotheses, the data suggest that intellectual deficits may be specific to hyperactive children and not a familial trait.     

Cluster analysis of child behavior checklists of 6 to 11-year-old males with varying degrees of behavior disorders

Achenbach Child Behavior Checklist ratings were collected on boys aged 6 to 11 years screened as not having significant behavior problems, as clinic-referred boys, and as boys diagnosed as having Attention Deficit-Hyperactivity Disorder alone or together with Oppositional-Defiant Disorder or Conduct Disorder. Cluster analysis resulted in a classification system related to DSM-III-R classification of the boys and parent self-report of mildly antisocial acts. Clusters also enhanced the ability of the instrument to detect Attention Deficit Hyperactivity Disorder and disruptive behavior disorders.     

Behavioral effects of hippocampal system lesions on rats in an operant paradigm

The effects on both operant and non-operant behavior during an operant task of various types of neural damage involving the hippocampal system were studied in adult male Sprague-Dawley rats. Various lesion types localized in the septal-hippocampal area all produced higher than control levels of operant responding under both a contingent variable interval and a non-contingent variable time schedule, an effect opposite to that seen in rats with ventral mesencephalic tegmental lesions. A different lesion effect was seen for the non-operant activity measure in that an activity hierarchy was noted, with colchicine-induced granule cell lesions producing the greatest activity increase and kainic acid-induced pyramidal cell lesions producing virtually no increase. Operant response rate was very sensitive to a switch in response contingency in that all groups significantly reduced operant responding while on the non-contingent schedule. This effect was not seen for the non-operant activity measure which appeared to be far less sensitive to contingency changes. The significance of these results to an understanding of the behavioral functioning of this system is discussed with some emphasis placed on their applicability to clinical cases of hyperactivity.     

Gilles de la Tourette's disease and minimal brain dysfunction: Amphetamine isomers reveal catecholamine correlates in an affected patient

Graduated doses of d- and l-isomers of amphetamine were administered on several occasions in double blind fashion to a patient with symptoms of both Gilles de la Tourettes disease and minimal brain dysfunction. d-Amphetamine markedly increased the frequency of ticking while l-amphetamine did not alter the tics. By contrast both isomers decreased the patient's hyperactivity to a similar extent. Based on the known differential influence of amphetamine isomers upon brain norepinephrine and dopamine, these findings suggest that aggravation of the tics is mediated by brain norepinephrine, while brain dopamine plays a major role in the alleviation of the symptoms of minimal brain dysfunction.     

Prenatal morphine administration alters behavioral development in the rat

Female rats were administered increasing doses of morphine sulfate 5 days prior to mating and during gestation until 4–6 days before the birth of their litters. Prenatal morphine exposure altered the normal developmental pattern of spontaneous motor activity by inducing in the offspring a sustained period of hyperactivity during the 3rd and 4th postnatal weeks. This disruption in behavioral ontogeny did not coincide with changes in physical parameters. Decreased body weight and higher mortality were observed in morphine-treated offspring only during the first postnatal week. The appearance of behavioral disturbances in the absence of physical abnormalities stresses the need for follow-up studies of infants born to narcotic-dependent mothers after signs of physical withdrawal or retarded growth have disappeared.     

Haloperidol-induced hyperactivity in neonatal rats: Effect of lithium and stimulants

The effect of chronic subcutaneous administration of haloperidol directly into neonatal rats was investigated as a possible model for the hyperkinetic syndrome in human children in terms of its onset, duration and offset of hyperactivity. In addition, the ability of chronically-administered lithium in the diet of nursing mothers to attenuate the haloperidol-induced hyperactivity was investigated. Experiments with acute administration of the clinically-effective stimulants, amphetamine and methylphenidate, to the pups were also conducted to determine the adequacy of this behavioral model vis-a-vis the human condition. The results indicate that, although chronic haloperidol (2.5 mg/kg) produces hyperactivity relative to controls on the 25th day of life, this hyperactive behavior does not return to control levels at 30 days of age. Moreover, neither the stimulants nor lithium attenuates this hyperactivity and, indeed, lithium, by itself, produces increased activity. Thus, chronic haloperidol administered directly into neonatal rat pups produces hyperactivity possibly by the production of dopaminergic supersensitivity, yet this effect does not model the temporal course seen in hyperkinetic humans. In addition, the administration of drugs that are clinically-useful in treating childhood hyperactivity were unable to decrease the hyperactivity produced by haloperidol in neonatal rats. Taken together, these observations cast doubt upon the usefulness of this animal model to mimic the human condition.     

Rehearsal Strategies and Recall Performance in Boys With and Without Attention Deficit Hyperactivity Disorder

Examined differences in recall performance and rehearsal strategiesin boys with Attention Deficit Hyperactivity Disorder (ADHD)and comparison boys using an overt rehearsal procedure on aself-paced, multitrial, free recall task. Boys with ADHD recalledfewer words, tended to spend less time rehearsing the items,and spent less time attempting to retrieve them. Although theydid not rehearse items less frequently than comparison boys,they relied almost exclusively on repetition of single items.In contrast, comparison boys showed some evidence of using active,multi-item (cumulative) rehearsal. Despite their failure touse cumulative rehearsal, boys with ADHD identified it as moreeffective than single-item rehearsal in a subsequent forced-choiceassessment of strategy knowledge.     

The adolescent outcome of hyperactive girls

The adolescent outcome of a complete cohort of 12 girls diagnosed hyperactive in childhood is compared with that of 24 hyperactive boys and 24 male control subjects matched for age and social class. The lifetime psychiatric history of parents was also assessed. No significant difference between the rate of mental disorder in adolescent hyperactive boys and girls was found. Also, the rate of lifetime adult psychiatric diagnosis in the parent groups did not differ significantly.     

Low birth weight and psychiatric morbidity; stability and change between adolescence and young adulthood

Background

Being born with low birth weight is a risk factor for psychiatric morbidity.Few longitudinal studies have included diagnostic assessment and followed subjects into adulthood.

Aim

To assess stability and change in psychiatric morbidity between adolescence and young adulthood in low birth weight subjects, and explore whether screening in adolescence can predict subsequent psychopathology in these groups.

Study design

Prospective geographically based follow-up study of two low birth weight groups and a control group born between 1986 and 1988, assessed at 14 (T1) and 20 (T2) years of age.

Subjects

Thirty eight subjects born preterm with very low birth weight (VLBW: ≤ 1500 g), 43 born at term but small for gestational age (SGA: < 10th percentile) and 64 controls with normal birth weight participated.

Outcome measures

Mental health was assessed using diagnostic psychiatric interview at both study points supplemented with the Achenbach System of Empirically Based Assessment and Children's Global Assessment Scale at T1.

Results

There was a trend towards increasing morbidity from T1 among VLBW (p = 0.086) and a significant increase among SGA (p = 0.003) participants. Supplementary assessment at T1 discriminated satisfactory between persons with and without psychiatric disorders at T2 (area under ROC curve: 0.66 to 0.89), but was most effective in the VLBW group.

Conclusion

High psychiatric morbidity continued into young adulthood in the VLBW group and increased significantly in the SGA group. Screening in adolescence can be used to detect individuals at risk especially among those born at very low birth weight.     

Motor examination in children with Attention-deficit/hyperactivity Disorder and Asperger Syndrome

Aim: Evaluating whether motor skills could differentiate drug‐naive subjects with two neurodevelopmental disorders: Attention‐Deficit Hyperactivity Disorder (ADHD) and Asperger Syndrome (AS). Methods: Thirty‐six boys (12 with ADHD, 12 with AS and 12 with typical development) aged 8–12 were evaluated using the Physical and Neurological Examination for Subtle Signs. Three primary outcome variables were obtained as follows: (i) total speed of timed activities, (ii) total overflow and (iii) total dysrhythmia. Results: Children with AS performed more slowly than those with ADHD and healthy children independently of age and IQ. Total dysrhythmia differentiates ADHD and AS children from controls. Conclusion: Dysfunction of the fronto‐striatal–cerebellar networks related to motor control could be the physiopathological basis of the reported findings.