Asymmetry of recall in depression.

We compared the verbal (auditory/semantic) and nonverbal (visual/configurational) recall of carefully defined depressed patients with a demographically matched control group of normal volunteers. Whereas controls were split as to whether their nonverbal recall exceeded or was inferior to their verbal recall, 89% of depressed patients demonstrated an asymmetry characterized by poorer nonverbal than verbal recall. Depressive subgroups (determined by clinical and psychoendocrine criteria) differed from controls, but not from each other, in demonstrating this asymmetry of recall. In contrast, depressed patients did not individually demonstrate an asymmetry between verbal and nonverbal recognition that differed from controls.

A comprehensive study of chronic schizophrenic patients. I. Quantitative computed tomography: cerebral density, ventricle and sulcal measures.

Based on recent computed tomography (CT) studies that have suggested the presence of distinct structural abnormalities in the brains of chronic schizophrenics, the authors evaluated 23 chronic schizophrenics and 23 controls by CT, using linear and area lateral ventricular measures, sulcal and Sylvian fissure widths and cerebral density measures. Technical problems inherent in CT studies and their impact on the use of data generated by such studies are discussed. Although there were few differences between groups, there emerged a distinct subgroup of schizophrenic patients with mild lateral ventricle enlargement associated with increased cortical density. The possible etiopathology for this atypical combination is discussed, including the striking parallels with a recent neuropathological study's findings.

The ventricular system in chronic schizophrenic patients. A controlled computed tomography study.

Twenty-three chronic schizophrenic patients and 23 controls, all males between 20 and 40 years of age, were evaluated by CT scan. The lateral, third and fourth ventricles, the Sylvian fissures, and the largest sulcus from each of the frontal, parietal, and occipital lobes, were measured in order to determine whether the previously reported ventriculomegaly in schizophrenics was perhaps due to a disturbance of CSF flow or to atrophy, two common causes of ventricular enlargement. We found that in the schizophrenic group the third and fourth ventricles and both Sylvian fissures were significantly enlarged, but not the lateral ventricles or cerebral sulci. Our data suggest that these ventricular changes are not due to a disturbance of CSF flow or to cerebral atrophy. Other possible explanations are discussed.

Central brain morphology in chronic schizophrenic patients: a controlled CT study.

A comprehensive quantitative computed tomography (CT) study of the diencephalic region of 23 chronic schizophrenic patients and 23 normal controls was done. The third ventricle width, the Sylvian fissure widths, and the densities of the head of the caudate nucleus, thalamic nucleus, and medial temporal lobe were measured. In the schizophrenic patients, there was a significant increase in third ventricle and Sylvian fissure widths and a significantly greater density of both periventricular nuclei. The several explanations for this atypical association of atrophy with greater density are discussed.

Cerebellar morphology in chronic schizophrenic patients: a controlled computed tomography study.

Simple, objective, linear, and density measures were used to evaluate by computed tomography (CT) the cerebellum-fourth ventricular region of 23 chronic schizophrenic patients and 23 normal controls. Our data suggest that a subgroup of chronic schizophrenic patients have cerebellar atrophy associated with a strong but nonsignificant trend toward increased cerebellar density. The implications of these findings are discussed in view of previous CT and neuropathological studies.

Reaction time facilitation in affective psychotic patients.

The extent to which the second member of a pair of monotic clicks facilitates simple reaction time was examined for 35 psychiatric patients and 43 non-patient controls across 2 studies. Affective psychotic patients showed greater reaction time facilitation than did either schizophrenic patients or non-patient controls. Computer simulations of a 'statistical facilitation' model for these data are also presented.

Auditory sensitivity in psychiatric patients and non-patients: monotic click detection.

The sensitivity in detecting a click was measured separately for the right and left ear of psychiatric patients and non-patient controls using a three-interval forced-choice staircase procedure. Patients with affective disorders showed reduced right ear sensitivity, while schizophrenic patients did not show reduced sensitivity. Lower sensitivity correlated with higher structured-interview ratings of speech retardation.

Dichotic perception: evidence for right hemisphere dysfunction in affective psychosis.

The association between lateralized hemispheric dysfunction and psychiatric diagnosis was investigated with a measure of summation of dichotic clicks and with a dichotic competing message task. Ear asymmetries of affective psychotic patients were similar to those of right temporal lesioned controls and differed from those of schizophrenic patients and normal controls. In contrast, schizophrenic patients did not display abnormal auditory perceptual asymmetries.

Auditory signal detectability and facilitation of simple reaction time in psychiatric patients and non-patients.

Patients diagnosed on the basis of structured interviews as having affective psychoses were less sensitive in detecting the presence of a transient auditory signal than were schizophrenic patients or non-patients. Patients with affective psychoses also benefited more (their reaction time was more reduced) than the other two groups from the presence of a second auditory transient.