Failure of acute and chronic administration of Δ9-tetrahydrocannabinol to affect the repeated acquisition of serial position responses in pigeons

Pigeons were trained to acquire a new four-response position sequence each day by pecking three response keys in a predetermined order. The key color varied after each correct response prior to food delivery. Acute administration of Γ⁹-tetrahydrocannabinol (Δ⁹-THC) up to a dose that completely eliminated responding, had no effect on total acquisition errors, or on within session patterns of error elimination. Chronic administration of Δ⁹-THC (3–10 mg/kg/day), either before or after the session for 4–7 weeks, also did not affect these error measures, although rates of responding were markedly suppressed and at times no responding occurred Discontinuation of Δ⁹-THC administration for periods of 4–6 weeks also was without effect on errors. These experiments suggest that neither acute nor chronic Δ⁹-THC produce specific effects on the repeated acquisition of serial position responses in pigeons.     

Long latency auditory evoked potentials

Experiment 1 elicited the P1, N1, P2, and N2 components of the long latency auditory evoked potential (AEP) using a 1000 Hz tone presented at 30, 50, or 70 dB SPL and 1-, 3-, or 5- second inter-stimulus intervals to assess the relative effects of the combination of these variables on component amplitude and latency. Four blocks of 16 tone presentations each were recorded from each subject to determine if changes in the AEP would occur because of short-term habituation. Both stimulus factors interacted significantly in a systematic fashion for the amplitude measures, with increases in latency also associated with increases in intensity and inter-stimulus interval. Only minor changes across the four trial blocks for either the amplitude or latency measures were observed over the various stimulus presentation conditions. Experiment 2 employed the same tone stimulus presented at 50 dB SPL and a 3-second inter-stimulus interval. Eight blocks of 64 trials were recorded from each subject on each day for four days to investigate long-term habituation effects. No substantial changes in any of the component amplitudes or latencies were obtained across the 32 trial blocks. It was concluded that intensity and inter-stimulus interval interact to determine AEP amplitude as well as latency values and that the constituent components do not change appreciably with repeated stimulus presentations, even after several days.     

Social sensitivity in adolescents and adults with learning disabilities.

This study investigated social sensitivity and self-concept in students with learning disabilities (LD) and their non-learning-disabled (non-LD) peers. Thirty students each from public junior and senior high schools and a community college participated in the study; at each grade level, half were identified as learning disabled and half experienced no learning problem. Students were individually assessed in 30-minute interviews for their accuracy in interpreting the thoughts and feelings of actors in tape-recorded stories depicting two adults in happy angry, anxious, and sad interactions. A questionnaire assessing four dimensions of self-concept in learning situations (motivation, task orientation, problem-solving ability, and class membership) was also administered. LD students at all grade levels were significantly less accurate at interpreting social situations than were their non-LD peers, and had significantly lower self-concepts. These results support the need for remediation efforts specifically aimed at social skills for overcoming social deficits in adulthood.     

The association between adolescents' attitudes toward suicide and their psychosocial background and suicidal tendencies.

The present study examined the relationship between adolescents' attitudes toward suicide and their psychosocial background. It also evaluated the association between attitudes toward suicide and the subjects' own suicidal tendencies. A questionnaire assessing these issues was administered to 525 Israeli adolescents. Results indicated that significantly more females, nonreligious adolescents, those exposed to suicidal behavior, and those with increased suicidal risk held more accepting attitudes. Ethnic origin, socioeconomic status, and living in intact/nonintact families were not associated with adolescents' attitudes toward suicide.     

Paranoid character and the intolerance of indifference.

This paper suggests that aspects of paranoid character are structured around fantasies of magical and concrete connectedness to objects; these fantasies serve to avoid the terrors of object inconstancy. The authors describe how these fantasies are expressed in the psychoanalytic situation and explore their relation to common paranoid phenomena. The paranoid person must maintain these fantasies of connectedness at all cost or risk experiencing unbearable indifference between self and object. Paradoxically, the sacrifice of self and object boundaries inherent in these fantasies makes object constancy even more difficult to achieve because of the secondary defensive use of anger mobilized to protect the boundaries of the self.     

Malevolent object representations in borderline personality disorder and major depression.

To study malevolent representations, earliest memories were reliably coded on scales of affect tone. Ss were diagnosed with borderline personality disorder: 31 without and 30 with concurrent major depression. Nonborderline comparison subjects had either major depressive disorder (n = 26) or no psychiatric diagnosis (n = 30). Borderline subjects were discriminated from comparison subjects by their more malevolent representations; they more frequently produced memories involving deliberate injury; and they portrayed potential helpers as less helpful. Results suggest the diagnostic significance of malevolent representations, which need to be explained by any theory of borderline personality disorder.     

Depression and social problem solving.

Twenty depressed patients with major depressive disorder, 20 nondepressed matched control subjects, and 17 patients with anxiety disorders were compared in different measures of social problem solving. Problem solving was assessed with the Means-Ends Problem-Solving Test (Study 1), the solution of personal problems, and a problem-solving questionnaire (Study 2). Results showed that, as predicted, depressed subjects suffered from a deficit in problem solving in all three measures. The majority of these deficits were also displayed by the clinical control group rather than being specific to a diagnosis of depression. However, depressed subjects produced less effective solutions than did normal and clinical control subjects. The results suggest that depressed and anxious patients may have difficulties at different stages of the problem-solving process.     

When depression breeds contempt: reassurance seeking, self-esteem, and rejection of depressed college students by their roommates.

To test Coyne's (1976b) theory of depression, students' levels of depressive symptoms, reassurance seeking, and self-esteem were assessed at Time 1, and their same-gender roommates' appraisals of them were assessed 5 weeks later. Mildly depressed students engaged in the type of reassurance seeking described by Coyne. Among men, but not women, mildly depressed students were rejected if they strongly sought reassurance and had low self-esteem but not if they did not seek reassurance or had high self-esteem. Although induction of depressed symptoms in roommates did occur, this contagion effect did not account for the depression-rejection relationship. The prediction that unsupportive, intolerant, or unempathic others would be particularly likely to respond with rejection to reassurance-seeking depressed students with low self-esteem received partial support. Implications for future work on the interpersonal aspects of depression are discussed.