Biomedical subjects

K F Berman

Publications and source records attributed to K F Berman.

62 records · Page 4Linked to original sources

PubMed1986

Physiologic dysfunction of dorsolateral prefrontal cortex in schizophrenia. II. Role of neuroleptic treatment, attention, and mental effort.

We conducted two xenon Xe 133 inhalation regional cerebral blood flow (rCBF) studies to clarify earlier findings of dorsolateral prefrontal cortex (DLPFC) dysfunction in medication-free patients with chronic schizophrenia. In the first study, 24 neuroleptic-treated patients and 25 normal controls underwent three rCBF procedures, first while at rest, then during the Wisconsin Card Sort (WCS), which tests DLPFC cognitive function, and during a number-matching task that controlled for aspects of the WCS-rCBF experience not specifically related to DLPFC. The results were qualitatively identical to those previously reported for medication-free patients. In the second study, rCBF was determined while 18 medication-free patients and 17 normal control subjects each performed two versions of a visual continuous performance task (CPT). No differences in DLPFC blood flow between the two groups were found during either CPT condition. These data suggest that DLPFC dysfunction in schizophrenia is independent of medication status and not determined simply by state factors such as attention, mental effort, or severity of psychotic symptoms. Dysfunction of DLPFC appears to be a cognitively linked physiologic deficit in this illness.

Adult↗

PubMed1984

Seasonal variation in human central dopamine activity.

This report focuses on two studies of seasonal variation of central dopamine activity in patients with schizophrenia and normal controls. In the two investigations, data were grouped and analyzed by season (i.e., spring-summer vs. fall-winter). The first study concerned blink rate, a putative measure of central dopamine activity; the blink rate for patients with schizophrenia was significantly increased during the spring-summer period. In the second study concentrations of catecholamines and their metabolites were measured in the hypothalamus and nucleus accumbens of normal and schizophrenic subjects. Findings include a reduced concentration of hypothalamus dopamine in normal controls and a reduced concentration of homovanillic acid in the nucleus accumbens of patients with schizophrenia, both during the spring-summer period.

Adult↗

PubMed1984

The Genain Quadruplets 25 years later: a diagnostic and biochemical followup.

A biological and clinical followup of the Genain Quadruplets was initiated as a multilaboratory collaborative effort at the National Institute of Mental Health (NIMH). The quadruplets are 51-year-old monozygotic women previously studied with a battery of psychological and physiological tests 25 years ago at the NIMH. The present article (the first of a series of three) details the clinical history and course of the schizophrenic illness in each of the quadruplets and describes the biochemical measures determined. The findings of elevated urinary phenylethylamine excretion, decreased plasma dopamine-beta-hydroxylase activity, and increased alpha-adrenergic receptor concentrations in all quadruplets warrant further genetic studies.

3,4-Dihydroxyphenylacetic Acid↗

PubMed1984

Eye-blinking and cerebral ventricular size in chronic schizophrenic patients.

Spontaneous eye-blinking, a possible measure of central dopaminergic activity, was studied in 55 drug-free chronic schizophrenic patients subdivided by cerebral ventricular size. Blink rates were higher in schizophrenic patients than in normal control subjects, regardless of cerebral ventricle size. Neuroleptics lowered blink rates in patients with normal ventricles but did not affect blink rates in patients with large ventricles. Insofar as blinking is a dopaminergic parameter, these findings suggest that the dopamine hypothesis of schizophrenia is most relevant in patients with normal ventricles.

Adult↗

PubMed1984

Neuroradiology in psychiatry.

This article explored methods of brain imaging as they relate to the practice of psychiatry. In particular, technical aspects and clinical applications of CAT scanning are reviewed, and some neurologic conditions that may masquerade as psychiatric illness are considered. Suggested guidelines for CAT scanning in psychiatric patients are put forth, and implications of recent research findings in psychiatric disorders are discussed. In closing, we offer the following caveat: As "psychiatric" symptoms may be the earliest sign of structural CNS disease, the psychiatrist may be the first physician to evaluate patients with neurologic abnormalities. Because even the neurologic consultant may not be alert to the possibility of psychiatric symptoms alone heralding CNS pathology, the decision to augment the clinical impression with neuroradiologic or other brain imaging adjuncts (and to choose among them) may rest solely with the psychiatrist. Of these adjuncts, CAT scanning is almost always the most conclusive and reliable.

Adolescent↗

PubMed1983

An inverse correlation between spontaneous eye-blink rate and platelet monoamine oxidase activity.

An inverse correlation between platelet monoamine oxidase activity and spontaneous eye-blink rate, a putative measure of central dopaminergic activity, was found in medication-free chronic schizophrenic patients without tardive dyskinesia (n = 20, rs = -.47, P less than .025). A similar correlation was found when patients with tardive dyskinesia were included but was weaker (n = 27, rs = -.35, P less than .05). Normal controls and patients with tardive dyskinesia did not demonstrate this relationship. This report confirms a previous finding of a significant platelet monoamine oxidase-blink rate correlation in chronic schizophrenic patients. Insofar as this relationship is mediated by dopamine, it suggests that dopaminergic relations are more readily demonstrated in schizophrenic subjects than normals. Moreover, tardive dyskinesia appears to obscure this dopaminergic relationship.

Adult↗

PubMed1981

Speaking, thinking, and blinking.

The effect of several mental tasks on the spontaneous eye blink rate in 36 normals was examined. The blink rate during silence was 19.0 blinks/minute. This was significantly lower than the mean blink rate during speech (24.7 blinks/minute) and while listening to a paragraph to be memorized (27.6 blinks/minute). Reading reduced the blink rate to 12.3 blinks/minute. Men were more able to suppress and speed up blinking than women.

Adult↗

PubMedDate not supplied

Recall memory deficit in schizophrenia. A possible manifestation of prefrontal dysfunction.

Patients with schizophrenia have memory deficits when compared to other neuropsychiatric and normal samples, but the mechanism by which the deficits arise is obscure. In the present study, 13 older, less educated normal subjects, and 31 inpatients with schizophrenia were administered the Selective Reminding test. In addition, the schizophrenic patients received the Mini Mental State Exam and the Brief Psychiatric Rating Scale. While normal subjects performed at a higher level on various measures of recall, a significant effect of repeated trials was present for each group for each measure, indicating that both groups learned. Normal subjects also outperformed the patients on a test of recognition memory. However, the patients exhibited a significantly greater disparity between recognition and recall than did the normal subjects, suggesting they were better able to acquire new information than to retrieve it ('forgetting to remember'). Moreover, anergia, a factor measure on the Brief Psychiatric Rating Scale, correlated significantly with recall, but not recognition memory, in the patient group. The data are suggestive of prefrontal-type cognitive and behavioral deficits in schizophrenia.

Adult↗