Evidence for a sex-specific residual effect of cannabis on visuospatial memory.

BACKGROUND: In an exploratory study, we used a novel computerized battery of neuropsychological tests of attention to assess residual cognitive impairment in marijuana users. METHODS: We compared 25 college students who were heavy marijuana smokers (who had smoked a median of 29 days in the last 30 days) with 30 students who were light smokers (who had smoked a median of 1 day in the last 30 days). All subjects were tested after a supervised period of abstinence from marijuana and other drugs lasting at least 19 h. RESULTS: Differences between the overall groups of heavy and light smokers did not reach statistical significance on the four subtests of attention administered. However, upon examining data for the two sexes separately, marked and significant differences were found between heavy- and light-smoking women on the subtest examining visuospatial memory. On this test, subjects were required to examine a 6 x 6 'checkerboard' of squares in which certain squares were shaded. The shaded squares were then erased and the subject was required to indicate with the mouse which squares had formerly been shaded. Increasing numbers of shaded squares were presented at each trial. The heavy-smoking women remembered significantly fewer squares on this test, and they made significantly more errors than the light-smoking women. These differences persisted despite different methods of analysis and consideration for possible confounding variables. CONCLUSIONS: This observation suggests that it may be important to study the residual effects of marijuana on men and women separately-particularly since women have been greatly underrepresented in previous studies in this area.

Impaired attention in depressive states: a non-specific deficit?

Although cognitive research on attention has advanced significantly in recent years, these advances have produced few specific hypotheses regarding the attentional impairment seen in depression, and few experiments designed to test them. We review the limited neuropsychological literature on impaired attention in depressive states, with emphasis on areas where the findings of modern cognitive research might be applied in the future to design more sophisticated tests of attentional impairment. At present, it is not possible to determine whether the attentional deficits seen in depression are specific to this disorder, or whether they represent a final common pathway of impaired cognition seen in many different mental and organic deficit states, such as schizophrenia and dementias.

[Exploration of memory disorders in anxiety states]. / Exploration des troubles de la mémoire dans les états anxieux.

According to cognitive model of anxiety, memory process in anxious patients is usually tested by comparing the incidental recall of positive and negative, threatening and non threatening, self and other-referenced words. Contrary to expectation, the results indicate relatively poorer memory for threatening material in anxious patients and no bias in favour of the recall of self referent negative words. At the opposite this memory bias can be evidenced in patients with panic disorder. The bias for anxiety words is better evidenced in the subgroups with the higher arousal level or when there is a mood induction by reading first an anxiogenic text. Consistent with prediction a perceptive pre-attentional bias can be shown for the great majority of the subjects studied in recent researches.

Bulimia in the late nineteenth century: the observations of Pierre Janet.

In 1903 Pierre Janet published perhaps the first detailed descriptions of patients with bulimia. Janet's observations, although anecdotal, are consistent with modern studies suggesting an association between bulimia and major affective disorder and between bulimia and anxiety disorders. Janet's writings also support the belief that bulimia is more prevalent today than a century ago.

Eye-tracking patterns in schizophrenia. An analysis based on the incidence of saccades.

Saccades occurring when tracking a sine-wave target and when fixating a stationary target were studied in the following three groups: schizophrenics, other psychiatric inpatients, and normal controls. The frequency of saccades when tracking and when fixating was significantly greater among schizophrenics than among the two comparison groups. The pattern of occurrence of saccades within cycles of the sine movement was similar in the three groups; the greatest occurrence was at the highest target velocity and the lowest occurrence was at reversal points. The data are interpreted as consistent with the hypothesis of a failure on inhibiting mechanisms.

[Present trends in biological psychiatry research on psychoses (author's transl)]. / Orientation actuelle des recherches en psychiatrie biologique dans les psychoses.

Most of the present biological hypothesis postulate biogenic amines disorders in schizophrenia: transmethylation and dopaminergic theory. Other systems which can modulate this neuro-transmitter, specially in the mesolimbic dopaminergic system, may be concerned: nor-epinephrine, serotonin or endorphins. A dysfunction in arousal and cerebral dominance has been described by the quantitative electroencephalography. Other electrophysiological studies are consistent with these results; they indicate an impairment of the level of arousal to which the disorders of attention and adaptation could be related. In affective psychoses the major hypothesis bear on norepinephrine or serotonin disorders. But other substances may have a role: acetylcholine and dopamine as well as electrolytic modifications of cell membranes or immunological or neuroendocrine disturbances. This biological and physiological fundamental research has numerous practical consequences as the discovery of compounds with a more specific effect, the research of biological and biochemical diagnostic indices, or the drawing up of biological indices for neuroleptics, antidepressants or lithium sensitivity.

[Normality, normativity and marginality]. / Normalité, normativité et marginalité.

Different points of view about sense of "normality" for psychiatrists are reviewed. It appears that there is not any satisfactory criterion which defines the limit between normal and abnormal. In the field of mental processes, normality is a valuation which is not independent of the psychiatrist's own values, and of his socio-cultural mode of thinking. One of the consequences of this is the risk of "normativity". Normativity indeed terms the imposition of norms on the subject which correspond to the ideal of the psychiatrist or to the ideal of the society, without respecting the individuality of the subject. It is recalled that social abnormality, or "marginality", i.e. the non-respect of social norms, should not be confused with psychiatric abnormality.

[Visual tracking disorders in schizophrenia. Review of the literature and methodological considerations]. / Les perturbations de la poursuite visuelle dans la schizophrénie. Revue de la littérature et considérations méthodologiques.

Since Holzman expressed the hypothesis that eye-tracking dysfunctions might be a genetic indicator of schizophrenia, the researches on the performances of schizophrenics in eye-tacking tasks have been numerous. The correlation between the results of all these researches leaves little doubt on the existence of eye-tacking dysfunctions in schizophrenics. But these distrubances must be precised. Up to now, the studies have used tests that were too complex in their interpretation (pendulum test) and they have been limited to a global appreciation of eye-tacking. To take into account the psychological parameters that may interfere with success in this type of tests, the coming researches should focus on elementary eye-motor activities.

[Childhood aphasia with epilepsy. Remission with antiepileptic treatment]. / Aphasie de l'enfant avec épilepsie. Evolution régressive sous traitement antiépileptique

The authors describe an example of an aphasic syndrome peculiar to children. This syndrome, which has previously been described by several authors, is characterized by an unusual form of aphasia, by its association with epileptic attacks, and by its onset in the absence of any apparent aetiology. In such cases, the effectiveness of anti-epileptic treatment on the aphasia is variable, often quite poor; on the other hand, in the case described in this report, administration of anti-epileptic treatment was followed by spectacular regression of the aphasia.