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J M Halperin

Publications and source records attributed to J M Halperin.

46 records · Page 3Linked to original sources

Preclinical evaluation of behavioral deficits following hypnotic drug treatment.

Most hypnotic medications result in performance decrements, or "hangover effects," the morning after bedtime ingestion. However, the severity of hangover effects with new compounds is difficult to predict prior to clinical trials. This paper describes a preclinical procedure that is predictive of human hangover effects following bedtime ingestion of hypnotic medication. Four cebus monkeys were shaped to discriminate between two levers such that rapid responses following the cue light maximized the probability of reinforcement. Subsequently, performance was evaluated one hr (immediate condition) and 8 3/4 hr (delayed condition) after the administration of flurazepam, triazolam, pentobarbital and placebo. All drugs caused dose-dependent performance decrements in both conditions. Significantly higher doses of triazolam were required to impair performance during the delayed condition as compared to the immediate condition, but no such differences occurred with either flurazepam or pentobarbital. These findings parallel human data which indicate that sleep-inducing doses of flurazepam and many barbiturates, but not triazolam, cause performance decrements the morning after bedtime ingestion.

Animals↗

Reading-disabled hyperactive children: a distinct subgroup of attention deficit disorder with hyperactivity?

Mixed hyperactive/reading-disabled children, selected from a large sample of hyperactive children, were compared to pure hyperactive children on demographic, behavioral, and neuropsychological measures. Children in the Mixed group were reading-disabled relative to age and IQ; those in the Pure group had achievement scores that were average relative to age and IQ. The Mixed group was significantly older than the Pure group; there were no differences in gender, race, or socioeconomic status. Behaviorally, the groups did not differ significantly on teacher ratings or on psychiatric ratings of aggression. The Mixed group had a significantly higher Performance IQ, whereas the Pure group had a significantly higher Verbal IQ and performed better on measures of cognitive impulsivity. Several other measures failed to distinguish the groups. The data give minimal support to the notion that pure hyperactive and mixed hyperactive/reading-disabled children constitute distinct subgroups of Attention Deficit Disorder with Hyperactivity.

Achievement↗

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

To test the hypothesis that intellectual deficits are trait shared by family members of hyperactive children, 18 hyperactive children were compared to their nonhyperactive siblings on measures of intelligence and academic achievement. As measured by the Wechsler Intelligence 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 whom adjusted for IQ. Contrary to previous hypotheses, the data suggest that intellectual deficits may be specific to hyperactive children and not a familial trait.

Achievement↗

Sleep-inducing effects of three hypnotics in a new model of insomnia in rats.

Sleep-inducing effects of hypnotic drugs are difficult to demonstrate in rats because of high baseline sleep times. Most increases in slow wave sleep (SWS) following the administration of hypnotics have been found to be at the expense of REM sleep rather than waking. In the first experiment we found that rats chronically implanted with electrodes for recording ECoG and EMG slept significantly less during the first two hours of the dark period when housed under 16-hr light 8-hr dark (16L/8D) than when housed under 12L/12D conditions. The second experiment examined the effects of flurazepam, phenobarbital and thalidomide administered orally at the onset of the two-hour period of increased waking resulting from the 16L/8D lighting. All three drugs caused dose-dependent reductions in waking and increases in SWS with no alterations in REM% of total sleep time. Sleep onset latency was also significantly was also significantly reduced by all three drugs. As in man, flurazepam was the most potent, and thalidomide was the least potent of the hypnotics in rats.

Animals↗

Protection from shock-induced seizures as a measure of hypnotic potency of drugs.

Mice injected with drug or vehicle were administered a 13 mA shock via corneal electrodes. The number of mice in which the shock produced a tonic seizure was recorded. The dose that blocked seizures in 50% of mice (ED50) was determined for each drug. The drugs evaluated consisted of 15 hypnotics, two antidepressants and two antihistamines. All hypnotics and antidepressants, and one antihistamine, caused a dose-dependent suppression of seizures. The ED50's were highly correlated with hypnotic potency in man. The advantages of this procedure, as compared to others currently used for the evaluation of hypnotic potential of novel compounds, are discussed.

Animals↗

Mode of inheritance influences behavioral expression and molecular control of cognitive deficits in female carriers of the fragile X syndrome.

The effect of mode of inheritance on expression of fragile X syndrome [fra(X)] was investigated in nonretarded female carriers. Examination included cognitive and molecular measures. A priori predictions about cognitive impairment and size of an unstable region of DNA containing a CGG repeat on the X chromosome were tested in age and education matched heterozygotes grouped according to parental inheritance. Nine carriers with a maternal fra(X) chromosome, 11 carriers with a paternal fra(X) chromosome and 15 control mothers of children with non X-linked developmental disabilities were tested. Inheritance was established through DNA linkage analysis. Cognitive skills were assessed using the Wechsler Adult Intelligence Scale-Revised and the Benton Visual Retention Test. Molecular status was assessed by Southern blot analysis of genomic DNA digested with Eco RI and Eag I, and probed with StB 12.3. Results supported the inheritance models' predictions. Heterozygotes who inherited the fra(X) from their fathers appeared to be a homogeneous group. They were indistinguishable from controls on cognitive measures and all had genomic insertions of less than 500 base pairs. In contrast, heterozygotes who inherited the fra(X) chromosome from their mothers appeared to be made up of 2 sub-populations. They were as a group deficient in measures of attention and visual memory, but not other measures, with scores of some women consistently below the other subjects. Further, they had some members with greater than 500 base pair inserts.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

ADHD and reading disabilities: a cluster analytic approach for distinguishing subgroups.

Data suggest that children with reading disability (RD) and non-RD children with attention-deficit/hyperactivity disorder (ADHD) may comprise distinct subgroups. Research has been hampered by variance in definitional criteria, which results in the study of different subgroups of children. Using cluster analysis, this study empirically divided children with ADHD (N = 54), based on their Full Scale IQ (FSIQ) and reading ability. Four distinct subgroups emerged in which cognitive, behavioral, and neurochemical function was compared. Cluster 1 was of average FSIQ and reading scores; Cluster 2 was of average FSIQ but showed impairment in reading; Cluster 3 had high FSIQ and reading scores; and Cluster 4 had low scores in both domains. The groups had different patterns of cognitive, behavioral, and neurochemical function, as determined by discrepancies in Verbal-Performance IQ, academic achievement scores, parent aggression ratings, and a measure of noradrenergic function. These distinctions are discussed with regard to etiology, treatment, and long-term outcome.

Aggression↗

Investigation of modality-specific distractibility in children.

Seventy-three nonreferred children were administered a battery of cognitive, academic and behavioral measures along with distinct tests of aural and visual distractibility. The data suggest that distractibility is modality specific. Completely distinct groups of visually- and aurally-distractible children were found. In addition, visual distractibility was associated with both a continuous performance test (CPT) measure of inattention and teacher ratings of behavior, but not with cognitive nor academic achievement measures. In contrast, aural distractibility was associated with cognitive functioning and reading scores, but not with the CPT inattention measure nor teacher behavior ratings.

Achievement↗