Effects of cocaine and alcohol, alone and in combination, on human learning and performance.

The acute effects of cocaine hydrochloride (4 to 96 mg/70 kg) and alcohol (0 to 1.0 g/kg), administered alone and in combination, were assessed in two experiments with human volunteers responding under a multiple schedule of repeated acquisition and performance of response chains. Subjects were intermittent users of cocaine and regular drinkers who were not cocaine or alcohol dependent. Alcohol was mixed with orange juice and ingested in six drinks within 30 min; cocaine was administered intranasally 45 min after completion of drinking. In each component of the multiple schedule, subjects completed response sequences using three keys of a numeric keypad. In the acquisition component, a new sequence was learned each session. In the performance component, the response sequence always remained the same. Results were consistent in both experiments, despite variations in the order in which the drugs were tested alone and in combination. Alcohol administered alone increased overall percentage of errors and decreased rates of responding in the acquisition component, whereas responding in the performance component generally was unaffected. Cocaine administered alone decreased rates of responding but did not affect accuracy of responding in the acquisition component, and enhanced accuracy of responding without affecting rates of responding in the performance component. The combined doses of cocaine and alcohol attenuated the effects observed with alcohol and cocaine alone. These results suggest that, under the conditions investigated in this study, (a) alcohol produces greater behavioral disruption than cocaine or cocaine-alcohol combinations, (b) cocaine and alcohol each attenuate effects of the other, and (c) such attenuation is most pronounced for cocaine attenuating the disruptive effects of alcohol.     

Relationship between religion-related factors and obsessive compulsive disorder

This exploratory study sought to determine whether selected religion-related factors differentiated between 86 patients with obsessive compulsive disorder (OCD), 73 patients with panic disorder, and 292 patients with other psychiatric (non-anxiety) disorders. A standard history questionnaire was used to obtain information from patients concerning religion of origin, involvement in religious activities, religious conflict, and perceived religiousness of parents. It was found that the percentage of patients who reported experiencing religious conflict was significantly higher for the OCD group than for the other two groups. Other findings suggested associations between Catholicism and OCD and between Protestantism and panic disorder, but further research is needed to clarify these relationships. This article is based on a paper presented at the 98th annual convention of the American Psychological Association, Boston, August 1990.     

Does Information That a Suicide Victim Was Psychiatrically Disturbed Reduce the Likelihood of Contagion?1

For example, psychological disturbance is stigmatizing, so knowledge that the suicide victim was psychiatrically disturbed may decrease the possibility that others will imitate the act. To assess this possibility, 306 undergraduate volunteers read a fictitious newspaper article about a 16-year-old high school sophomore, Pat, who committed suicide. There were 7 variations of the article, 4 containing negative circumstances (psychiatric disturbance, romantic relationship breakup, parents’ divorce, alcohol problems), and 2 containing positive circumstances (being a varsity athlete, being an honors student). A control group received no information about circumstances. Knowledge of Pat's life circumstances had no effect on respondents’ estimates of the possibility of the suicide being imitated, but did affect attitudes about the suicidal act itself and attitudes toward Pat's family. Apparently the circumstances surrounding the suicide have no affect on respondents’ estimates of themselves following suit, but do affect how they see the victim and bereaved family.     

An inverse relationship between baseline fixed-interval response rate and the effects of a tandem response requirement.

Previous experiments examining the effects of adding a tandem fixed-ratio response requirement on fixed-interval schedule performance have reported inconsistent results. One variable that may account for such inconsistencies is the baseline response rate in the fixed-interval condition. This possibility was investigated in the present study. Rats were given histories with either interresponse times greater than 11 s or fixed-ratio 40 schedules of reinforcement, which engendered either relatively low or high rates of responding, respectively, in the subsequent fixed-interval condition. A tandem ratio response requirement (fixed-ratio 9) was then introduced. The effects of adding this tandem response requirement were inversely related to the baseline fixed-interval response rates; low rates of responding in the fixed-interval condition were markedly increased, whereas high rates of responding were relatively unaffected. This inverse relationship appears to be similar to the rate-dependent relations observed in behavioral pharmacology. These results may provide an explanation for the inconsistent findings reported in previous studies on tandem fixed-interval fixed-ratio schedules and suggest that principles of behavioral pharmacology research may be applicable to the study of the effects of nonpharmacological variables on schedule-controlled behavior.     

The High School Dropout Goes to College

662 former secondary school leavers of academic potential were identified for a program designed to give selected dropouts a chance to enter the University of Toledo. Following responses to questionnaires, 94 students were selected for further screening, which resulted in the final selection of 50 candidates. 34 members of the experimental group attended pre-school workshops in reading, writing, and study habit skills. 31 enrolled as regularly admitted students in academic programs of the university for the academic year. 11 completed their freshman year, although only 4 were making satisfactory academic progress.