Juan C. Negrete

Cannabis affects the severity of schizophrenic symptoms: results of a clinical survey

Data on the history of cannabis use and a spot urine test for cannabinoids were obtained for 137 schizophrenics in treatment. Subjects who were using cannabis during the 6-month observation period presented with a significantly higher degree of delusional and hallucinatory activity than those who did not. Moreover, the group using cannabis made a higher average number of visits to the hospital during the same period. The status of cannabis use appeared to contribute to such variance more than did other relevant factors (age, stage of the illness, amount of medication prescribed, occasional use of other psychoactive substances).

Apomorphine-induced penile tumescence in impotent patients — preliminary findings

Apomorphine (Apo), a short acting dopamine (DA) receptor agonist induces penile erections in normal subjects. The erectile response to one or more doses of Apo HCl (0.25, 0.5, 0.75, 1.0 mg sc) or placebo was investigated in eight impotent subjects and penile tumescence monitored using a mercury strain gauge and strip chart recording. Four patients showed a full erection with Apo and one a partial response. Distressing side effects (nausea, sweating) were associated with non-response or partial response. Three responders to Apo were treated with low doses of the long acting DA receptor agonist, bromocriptine (2.5-3.75 mg/d po); all three showed complete recovery of erectile function within two weeks. A subgroup of impotent patients may have impaired central DA function. Testing with Apo may provide a diagnostic and predictive test to identify such patients who may respond to treatment with low doses of bromocriptine or other DA receptor agonist.

Alexithymia in Substance Abusers: Persistence and Correlates of Variance

The authors investigated the effects of detoxification on alexithymia scores in a sample of psychoactive substance-dependent patients. At baseline, 48 subjects were administered the 20-item Toronto Alexithymia Scale (TAS-20); a second measurement was carried out 4-6 weeks later. The mean TAS-20 total score of these subjects at baseline (55-5 ± 12.0) was higher than healthy population norms (46.5 ± 10.3), and no significant change in totals was elicited after detoxification. The results suggest that, in substance abusers, alexithymia tends to be a stable trait and is not significantly altered as a result of abstinence.

Cue-evoked arousal in cocaine users: a study of variance and predictive value

Thirty-six cocaine abusers in treatment and 16 non-using controls were exposed to visual cocaine cues; measurements included changes in skin conductance and a rating of psychological arousal (persisting cocaine thoughts and images during the 24 h following the experiment). The GSI score of the HSCL-58 was used as an indicator of psychological distress. Probands showed arousal responses significantly higher than the controls. Skin conductance readings correlated positively with HSCL-58 scores and with severity of craving in the week prior to the trial. Unexpectedly, they correlated negatively with duration of cocaine use and did not vary as a function of the severity of cocaine addiction or the duration of cocaine abstinence prior to the test. Neither cocaine addiction measurements nor arousal responses were found to predict cessation of use (a minimum of 3 months of sustained abstinence) 1 year after the test.

Speech processing ability in alcoholics: A transient impairment and its relation to field dependence

Alcoholic and non-alcoholic subjects received a test of the ability to identify speech presented against competing speech (Synthetic Sentence Identification) and a test of field dependence (Embedded-Figures Test (EFT). Performance on the speech task (which involved auditory figure-ground differentiation) bore no special relationship to performance on the field-dependence test. However, cross-sectional and longitudinal data suggested that recently-drinking alcoholics are temporarily impaired in their speech-processing ability, recovering this ability after several months of alcohol-abstinence. A relationship between chronicity of alcoholism and field dependence was also observed. The latter relationship, along with findings on auditory tests, were discussed in terms of their relevance to the issue of whether field dependence is an antecedent to or a consequence of alcoholism.