St. Elizabeths Hospital

About: St. Elizabeths Hospital is a healthcare organization based out in Washington D.C., District of Columbia, United States. It is known for research contribution in the topics: Dopamine & Schizophrenia. The organization has 575 authors who have published 588 publications receiving 35325 citations.

Neuroleptics and the Natural Course of Schizophrenia

Abstract: To determine if neuroleptic treatment changes the natural course of schizophrenia, 22 studies were reviewed in which relatively similar patients were or were not given neuroleptics at specific times during the course of their illness. Nineteen of the studies were from first- or predominantly first-break populations. While there was little consensus among the authors of the studies reviewed, a reanalysis of the data indicates that early intervention with neuroleptics in first-break schizophrenic patients increases the likelihood of an improved long-term course. This finding is similar to that of earlier investigators who indicated there was a decrease in patients with the more severe forms of the illness following the introduction of convulsive therapies. Furthermore, there is evidence that stable schizophrenic patients whose neuroleptics are discontinued and have relapses may have a difficult time returning to their previous level of function. The findings describe in this paper have implications for both the treatment of schizophrenia and for understanding the pathophysiological processes that determine the course of the disorder.

Evidence of dysfunction of a prefrontal-limbic network in schizophrenia: a magnetic resonance imaging and regional cerebral blood flow study of discordant monozygotic twins.

Abstract: Objective: The authors previously reported that in monozygotic twins discordant for schizophrenia the affected twin almost invariably had a smaller anterior pes hippocampus, measured with magnetic resonance imaging (MRI), and invariably had less regional cerebral blood flow (rCBF) in the dorsolateralprefrontal cortex duringperformance ofthe Wisconsin Card Sorting Test. The present study was an investigation ofthe relationship between hippocampalpathology and prefrontal hypofunction in the same twin pairs. Method: Nine pairs of monozygotic twins discordant for schizophrenia underwent MRI scanning for determination of anterior hippocampalvolume andxenon-inhalation rCBF testingfor determination of prefrontal physiological activation associated with the Wisconsin Card Sorting Test. Results: The differences within twin pairs on the MRI and rCBF measures were strongly and selectively correlated. Specifically, the more an affected twin differed from the unaffected twin in left hippocampal volume, the more they differed in prefrontal physiological activation during the Wisconsin Card Sorting Test. In the affected twins as a group, prefrontal activation was strongly related to both left and right hippocampal volume. These relationships were not found in the group ofunaffected twins. Conclusions: This finding is consistent with the notion that schizophrenia involves pathology ofand dysfunction within a widely distributed neocortical-limbic neural network that has been implicated in, among other activities, the performance ofcognitive tasks requiring working memory. (Am J Psychiatry 1992; 149:890-897)

Physiological dysfunction of dorsolateral prefrontal cortex in schizophrenia. III. A new cohort and evidence for a monoaminergic mechanism.

Abstract: We previously reported that compared with normals, patients with chronic schizophrenia have reduced regional cerebral blood flow (rCBF) in dorsolateral prefrontal cortex (DLPFC) during performance of the Wisconsin Card Sort Test (WCS), a DLPFC-related cognitive task, but not during nonprefrontal tasks, such as a simple number-matching (NM) test. We also found that unlike normals, patients failed to activate DLPFC during the WCS over their own baseline (NM) level. To explore the reproducibility of these findings, a new cohort of 16 medication-free patients underwent a series of xenon 133 inhalation rCBF studies under the following conditions: at rest, while performing the WCS, and while performing NM. The results confirmed our earlier findings. In addition, the concentrations in cerebrospinal fluid of homovanillic acid and 5-hydroxyindoleacetic acid correlated with prefrontal rCBF during the WCS but not during the NM test or at rest. The results show that behavior-specific hypofunction of DLPFC in schizophrenia is reproducible, and they implicate a monoaminergic mechanism.

Human serial learning: enhancement with arecholine and choline impairment with scopolamine

Abstract: Arecholine (4 milligrams), a cholinergic agonist, and choline (10 grams), a precursor of acetylcholine, significantly enhanced serial learning in normal human subjects. The subjects received methscopolamine prior to both arecholine and placebo injections. Conversely, scopolamine (0.5 milligram), a cholinergic antagonist, impaired learning and this impairment was reversed by arecholine and choline and the impairment after scopolamine were inversely proportional to the subject's performance on placebo; that is, "poor" performers were more vulnerable to both the enhancing effect of cholinergic agonist and precursor and the impairment after cholinergic antagonist than "good" performers.