Biomedical subjects

A C Parrott

Publications and source records attributed to A C Parrott.

61 records · Page 4Linked to original sources

PubMed1978

Clobazam. A 1.5 benzodiazepine derivative: effects upon human psychomotor performance under different levels of task reinforcement.

Two dose levels of clobazam, a benzodiazepine derivative, were compared to placebo for their effects upon psychomotor performance in an acute dose daytime study with normals. An acute dose of 10 mg clobazam significantly reduced response latencies in the low reinforcement condition of a psychomotor performance task but not in the high reinforcement condition. However 20 mg clobazam did not produce any significant changes in performance under either low or high reinforcement. Response speed changes generally correlated positively with trait anziety and neuroticism scores at both doses of clobazam.

Adult↗

PubMed1978

The effect of a sub-chronic administration of three dose levels of a 1,5-benzodiazepine derivative, clobazam, on subjective assessments of sleep and aspects of psychomotor performance the morning following night time medication.

The effect of repeated doses of a 1,5-benzodiazepine derivative, clobazam, at doses of 20, 30, and 40 mg taken at night was assessed the morning following medication on a variety of subjective and objective measures of sleep and psychomotor performance. None of the three dose levels of the drug produced any significant changes in critical flicher fusion thresholds or in complex reaction time tasks. Conceptual learning ability was not impaired by any of the doses of clobazam administered. Clobazam was rated on a self-scoring analogue rating scale as an effective sleep inducer, which also improved the perceived quality of sleep. There was also a reduction in the perceived integrity of early morning behaviour commensurate with the reported ease of getting to sleep.

Adult↗

PubMed1977

A repeated dose comparison of dichloralphenazone, flunitrazepam and amylobarbitone sodium on some aspects of sleep and early morning behaviour in normal subjects.

1 Seven normal subjects were given three different hypnotics (flunitrazepam 1 mg, amylobarbitone sodium 100 mg and dichloralphenazone 1300 mg) for four consecutive nights each. 2 All three substances improved subjective assessment of the ease of getting to sleep. Flunitrazepam was rated as better than eithr dichloralphenazone or amylobarbitone sodium in this respect. 3 The perceived quality of induced sleep was not altered by any of the preparations. 4 There was a disturbance of the subjective ratings of getting to sleep following cessation of treatment with dichloralphenazone, giving tentative support to the existence of a 'rebound' effect. 5 Dichloralphenazone produced an impairment in psychomotor performance as measured on a complex reaction time test following four nights medication with the drug.

Adolescent↗

PubMed1977

Repeated dose comparison of nomifensine, imipramine and placebo on subjective assessments of sleep and objective measures of psychomotor performance.

1. Nine normal subjects volunteered to participate in a randomized single-blind crossover study of nomifensine 75 mg and two comparators, imipramine 75 mg and placebo. 2. Each volunteer received placebo for 3 d, then the first test drug for 4 days. This sequence was repeated twice more, so that each subject received each comparator. All medication was taken three times daily. 3. Assessments were made on days 3, 5 and 7 of each sequence, and consisted of a Sleep Evaluation Questionnaire, a test of Critical Flicker Fusion and a measure of Complex Reaction Time (CRT). 4. There were no significant differences in the CRT. There was a significant increase in critical flicker fusion with nomifensine. 5. Although both nomifensine and imipramine disturbed the quality of sleep, only imipramine produced a hangover.

Adult↗

PubMedDate not supplied

The effects of an ergot alkaloid derivative (Hydergine) on aspects of psychomotor performance, arousal, and cognitive processing ability.

Hydergine, 12 mg per day for two weeks, has some direct activity on a variety of tasks of mental and cognitive performance. These results add support to biochemical findings that implicate the ergot alkaloids (particularly co-dergo-crine, Hydergine) in cellular activity likely to increase cortical arousal and awareness. The high dose of Hydergine used in this volunteer study was exceptionally well tolerated and did produce significant results on individual measures of central nervous system activity which might suggest the use of similar doses in patient populations. The findings of a hangover of activity after drug withdrawal and the fact that some CNS activity (serial subtraction of 17s) is not obvious until two weeks of medication would suggest the need for pharmacokinetic measures to be taken in conjunction with psychologic assessments. It would seem that a two-week schedule of repeated doses is the minimum required to produce an effect on CNS activity, but even with such a dose regimen it appears that the drug continues to exert some effect after its withdrawal.

Arousal↗

PubMedDate not supplied

Cigarette smoking: effects upon self-rated stress and arousal over the day.

Feelings of stress and arousal were assessed over a day of cigarette smoking. Smokers reported heightened stress prior to smoking, and reduced stress immediately after smoking (p < .002). Feelings of arousal were also significantly affected by cigarette use, with lower arousal prior to smoking, and increased arousal postsmoking (p < .011). This pattern was found with both "sedative" and "stimulant" smokers, as defined by the Smoking Motive Questionnaire (SMQ). These findings demonstrate that smoking can simultaneously produce both increased arousal and decreased stress. They lend doubt to the arousal modulation theory, which states that smoking leads either to reduced stress, or to increased arousal, but not both together. The present data broadly replicated some earlier findings (O'Neill & Parrott, 1992), and confirmed that smokers experience vacilating feelings of stress and arousal over the day. Thus, while feeling-state improvements often accompany cigarette smoking, they are followed by negative feelings (during nicotine withdrawal), which are alleviated by the next cigarette. These feeling-state changes also provide a clear psychological rationale for the repetitive/addictive nature of tobacco use.

Adult↗

PubMedDate not supplied

Psychological functions served by nicotine chewing gum.

All 43 participants in a smoking cessation study complete Russell's (1974) Smoking Motivation Questionnaire (SMQ) before quitting, and an equivalent Nicotine gum Questionnaire (NGQ) during cessation. The profiles of SMQ and NGQ scores were very similar, showing that nicotine gum served a range of psychological functions similar to that provided by cigarettes: stress modulation, feelings of arousal and pleasure, hand/mouth activity, and nicotine dependency. Gum scores were, however, around 45% of cigarette values, as would be expected from its lower nicotine dose. Failed quitters (less than 2 weeks abstinence, N = 15), short-term quitters (3-12 weeks abstinence, N = 14), and successful quitters (+13 weeks abstinence: N = 14), did not differ on any SMQ subscale. However, they did differ significantly on the NGQ habit subscale. Thus the development of a regular gum-chewing habit during the first week of cessation was associated with eventual success in quitting. Sex differences were also apparent, with females reporting higher sedative, stimulant, and hand/mouth activity gum-questionnaire scores than males. These findings provide evidence for the construct and content validity of the NGQ, but further studies into its criterion validity and test-retest reliability are required.

Adult↗