[Memory performance and instruction effects in schizophrenia. A comparative study of chronic schizophrenic patients and healthy probands]

34 chronically schizophrenic persons were matched with 34 healthy control participants according to age, level of education, and sex and received memory tests (short-term, priming, working, prospective, episodic, source and semantic long-term memory) and tests of attention and intelligence. Patients performed worse on all tests. The patients' memory deficits compared with controls are nearly one standard deviation greater than the differences in attention and intelligence. The deficits are smaller for priming and semantic long-term memory than for short-term, working, prospective, episodic, and source memory. After one short instruction all patients and controls received a repeat administration of the tests. Patients showed a lower, but also significant improvement for short-term, working, and prospective memory. We conclude that schizophrenia patients might suffer from specific memory deficits (specific vulnerability of strategic and thus of interference- or context-sensitive memory tasks) not attributable to more general psychopathologic symptoms.

Is resting anterior EEG alpha asymmetry a trait marker for depression? Findings for healthy adults and clinically depressed patients

Several lines of evidence suggest that asymmetric anterior brain activation is related to affective style, linking left hemisphere activation to positive affect and right hemisphere activation to negative affect. However, previous reports of left frontal hypoactivation in depressed patients were not confirmed in recent studies. This study evaluated additional characteristics of resting EEG alpha (8-13 Hz) asymmetry in 15 clinically depressed patients and 22 healthy adults by recording EEG activity on two separate occasions, 2-4 weeks apart. Across both sessions, group differences in anterior EEG asymmetry were compatible with the original hypothesis. However, groups differed in temporal stability of anterior EEG asymmetry, which was retest reliable in controls but not depressed patients. In contrast, temporal stability of posterior EEG asymmetry was acceptable in both groups. Increased variability of anterior EEG asymmetry may be a characteristic feature for depression, and, if so, this would challenge the notion that anterior EEG alpha asymmetry is a trait marker for depression.

Sensation seeking and affective disorders: characteristics in the intensity dependence of acoustic evoked potentials

Augmenting/reducing of the evoked potential has been shown to be related to sensation seeking (SS) and specific clinical disorders. Buchsbaum demonstrated that patients with bipolar affective disorders (BAD) tend to be augmenters, as is the case with sensation seekers, and patients with unipolar affective disorders (UPD) tend to be reducers. In addition, he reported that prophylactic medication reduced the tendency to augment in bipolar patients. However, evidence for these relations is restricted to a few studies. This study explores whether Buchsbaum's initial findings can be found in a naturalistic clinical setting. Acoustic evoked potentials were recorded for six levels of intensity (59, 71, 79, 88, 92, 96 dB SPL) from 24 healthy adults, 21 unipolar depressed patients, and 21 patients with BAD. Participants also completed personality questionnaires, especially the Sensation Seeking Scales Form V. Results revealed a positive correlation between SS and augmenting/reducing in healthy controls, thereby replicating earlier findings. Bipolar depressed patients showed larger P1/N1 slopes than healthy controls, when medication was statistically controlled. Unipolar depressed patients showed smaller P2 slopes, but only when medication was not controlled. Implications of these results for further research on augmenting/reducing and affective disorders and their relationship to SS are discussed.

Olanzapine-induced agranulocytosis

The antipsychotic drug olanzapine was developed to reduce the risk of haematotoxicity. We report a case of agranulocytosis induced by olanzapine.