George C. Stone

Psychological studies of marijuana and alcohol in man.

Regular users of marijuana (cannabis sativa) were given smoked and orally administered marijuana, a placebo, or alcohol. They were unable to distinguish between smoked marijuana and the tetrahydrocannabinol-free placebo. The oral administration of tincture of cannabis produced primarily dysphoric symptoms and was similar to alcohol in this respect. The smoked marijuana altered pulse rate, time estimation, and EEG, but had no effect on a measure of field dependence or on a digit symbol substitution task. Both drugs appeared to be mild intoxicants in a laboratory setting. Consideration of the dose, prior experience with drugs, setting, and possible cross tolerance of marijuana and alcohol are important in evaluating the significance of the clinical effects.

Combined effects of alcohol and sleep deprivation in normal young adults

The effect of combining sleep deprivation and moderate alcohol consumption in male college students differed from the effects of each treatment alone. Following either alcohol or sleep deprivation, there was mild performance impairment, decreased alertness and reduced amplitude and increased latency of cortical evoked potential (EP) components. Heart rate increased after alcohol and anxiety increased after sleep deprivation. When alcohol and sleep deprivation were combined, antagonistic effects were found for most measures (reaction time, heart rate, alertness, anxiety, latency of early EP components), but synergistic effects also occurred (performance accuracy, latency of late EP components). These effects were found in a doubleblind experiment using 24 subjects. The experimental treatments were alcohol doses of 0, 0.45 and 0.90 ml/kg of 95% ethanol and 0 and 26 h of sleep deprivation.

Adolescent Egocentrism and Feelings of Invulnerability Are they Related

This study examined the relationship between adolescent egocentrism and perceptions of risk in a sample of 458 middle school adolescents. Enrights Adolescent Egocentrism Scale (AES) and Elkinds Imaginary Audience Scale (IAS) were used to assess egocentrism. Analyses revealed unexpected findings regarding the relationship of the two egocentrism scales to risk perception. For females, high scores on the AES were associated with perceptions of high risk, and high scores on the IAS were weakly related to perceptions of low risk. Neither scale was related to risk perceptions for males. Theoretical and measurement issues are discussed.

Effects of drugs on nondiscriminated avoidance behavior

SummaryThirteen male, Long-Evans rats were trained to press a lever to postpone a brief electric shock. Each rat was subjected to several different doses of chlorpromazine, d-amphetamine, atropine and benactyzine, and then tested for four hours under a mixed schedule of extinction and nondiscriminated avoidance behavior. In comparison with interspersed control sessions, chlorpromazine produced a consistent depression. Amphetamine increased response rates at moderate doses, and led to severely toxic reactions at higher doses. The three anticholinergic drugs produced qualitatively similar reactions within rats, but very different patterns of response between rats. Most animals showed higher response rates, but a few were depressed.Rats differed markedly in their response to all of the drugs. Both quantitative differences in the dosage necessary to produce a common effect and qualitative differences in the pattern of response to the drug were seen.

Peripheral Vasoconstriction Induced By Emotional Stress in Rats

a psychologic defense mechanism and that the development of arthritis often occurs after ego syntonic gratifications through muscular activity are blocked and the need for activity is frustrated. The development of peripheral rheumatoid arthritis in an extremely active patient after the occurrence of a myocardial infarct which drastically reduced his permissible activity level is a case in point. In his review of the literature Gardner’ states I that none of the various infective, chemical, immunologic and physical means tried has succeeded in experimentally inducing a condition

An international review of the emergence and development of health psychology

Abstract This article presents an historical review of the development of the field of health psychology and traces its progress from its conceptual beginnings until the present. Events are chronicled in most regions of the world and the status of the field is given for these regions with a summary of the current activities taking place. Three hypotheses are posited regarding the future development of the field with respect to its status in the country 1. The identification of health psychology as a specific field has led to its expansion and development. 2. The history and status of psychology itself plays a major role in determining a country or regions receptivity to health psychology. 3. Where psychology is strong and autonomous and where health research and service is not dominated by medicine and psychiatry, health psychology will flourish.

Chlorpromazine slows decay of visual short-term memory

The effects of chlorpromazine, scopolamine, and pentobarbital on the visual short-term memory trace were studied using Sperling’s method. Ss were classified as introverts or extraverts with the Maudsley Test, but this variable had no significant effect. Analysis of variance showed a significant difference among the drug treatments (p <.05). The mean numbers of correct responses for scopolamine, pentobarbital, and placebo, among which there was no significant difference, were pooled and found to differ significantly from the chlorpromazine mean (p <.01). It was concluded that chlorpromazine improved performance either by filtering poststimulus “noise” or by delaying the encoding process for the visual STM trace, thereby making the information available longer.

Effects of practice on marijuana-induced changes in reaction time

The effect of smoked marijuana on performance of complex reaction time (RT) tasks was studied in two groups receiving different amounts of practice. Group M-P had no undrugged practice on the task before performing during marijuana intoxication for four consecutive daily sessions. On the fifth test day they performed while non-intoxicated. Group P-M performed the task on four consecutive test days while non-intoxicated, then smoked marijuana on session 5. Significant RT slowing was found on session 1 for group M-P (performing during marijuana intoxication without prior practice). Performance of this group improved rapidly and by the end of session 2 was not different from undrugged performance. Group P-M (receiving four sessions of undrugged practice before marijuana intoxication) showed no RT slowing while intoxicated. Reaction time performance may involve two phases: an early, attention-demanding phase which is sensitive to drug effects and a later, “automatic”, phase which results from practice and is more resistant to drug effects.Pulse rate, salivary flow and subjective responses were recorded before and after smoking. These physiological and subjective measures showed only slight reduction in the acute effects of the drug over the four days of repeated usage.

Effects of stimulus probability on reaction time in a number-naming task

Subjects were required to respond to the visual presentation of numerals by uttering syllables closely resembling the names of the numerals. Information in stimulus ensembles was varied by manipulating the number of alternative stimulus configurations that could appear, the relative frequencies of stimuli within an ensemble and the probability of a response being required. An increasing linear function was a good first approximation to the relation between reaction time and information transmission. Systematic deviations from this function were found and an attempt is made to explain them by introducing an intervening variable, “effective probability.”

Teaching Psychology to Medical Students.

Psychologists in any professional setting outside of their discipline will find here some important principles of adapting to different teaching needs.