Marijuana Revisited

This review examines recent research on the psychological effects of marijuana. The article contains material on potency, research problems, use patterns in the United States, and expectancy, as well as a review of research on acute effects, including psychosis, toxic delerium, acute anxiety, and brain damage. Nonacute effects are also examined, with material on studies of amotivational syndrome, intellectual functioning, memory, sexual activity, and driving. Research on marijuana's relationship to other drugs and to criminal behavior is also evaluated. Implications for counselors are discussed. Counselors are urged to help provide accurate information to users and to encourage an informed-decision approach. The significance of marijuana use to value and life-style choice and the counselor's role in considering marijuana law changes are evaluated.     

Adaptation in distance perception with head-movement parallax serving as the veridical cue

When head-movement parallax functioned as the sole veridical distance cue during exposure to spectacles that altered the eyes’ oculomotor adjustments, sizable adaptation was obtained. This result showed that a discrimination of the distances of 60 and 30 cm can be based on head-movement parallax. Using adaptation in demonstrating that head-movement parallax can serve as a distance cue circumvents the problem that the presence of accommodation normally presents when such a demonstration is attempted. The usual contamination of head-movement parallax with accommodation is avoided, because accommodation is altered by the spectacles and does pot function as a veridical cue along with head-movement parallax.     

Perceived objectivity and the effects of evaluative reinforcement upon compliance and self-evaluation in blacks

Two experiments were conducted to investigate the effects of positive and negative reinforcements upon black college students. In the first experiment subjects received either positive or negative reinforcement from a black or a white Evaluator. Behavioral change (compliance) was greater in response to negative reinforcement from a black Evaluator than in response to negative reinforcement from a white Evaluator, while there were no divergent effects of Evaluator's Race upon compliance with positive reinforcement. The same pattern obtained in subjects' self-evaluations. The second experiment offered a test of the hypothesis that the objectivity of black Evaluators was perceived as greater than that of white Evaluators, and that a manipulation aimed at equating the Evaluators on objectivity would attenuate the effects of Evaluator's Race upon compliance and self-evaluation in response to negative reinforcement. These hypotheses were generally supported by the results.     

Handedness and stuttering: A dead horse?

A handedness questionnaire was administered to 446 stutterers and a control group. No significant male/female or stutterer/control effects were found, although both males and stutterers tended to be less right handed. The slight sex effect in handedness is consistent with previously reported studies and with cerebral structural and functional asymmetries.     

INTERACTIONS BETWEEN TEACHER GUIDANCE AND CONTINGENT ACCESS TO PLAY IN DEVELOPING PREACADEMIC SKILLS OF DEVIANT PRESCHOOL CHILDREN1

Token-mediated access to play and snacks was made contingent on completion of academic tasks in the Baseline Experiment. This contingency produced stable completion rates that were subsequently doubled, and then tripled, for four deviant children in a special preschool. A reversal design demonstrated that the contingency was functional in maintaining the children's rates of task completion. The Guidance Experiment examined the role of a social event, teacher guidance, in the acquisition of task-completion skills, in a multiple-baseline-across-tasks design (with reversals). The analysis demonstrated that teacher guidance was an important supplement to the token-mediated contingency in establishing significant increases in task completions for a second group of three deviant children in the special class. The importance of teacher guidance was related to the difficulty level of the children's tasks.