Showing papers by "Stephan F. Taylor published in 1996"

Alteration of corticothalamic perfusion ratios during a PTSD flashback

Abstract: We performed a single photon emission computed tomography (SPECT) study of patients with posttraumatic stress disorder (PTSD) by measuring changes in regional cerebral blood flow (rCBF) during provocation by combat stimuli. A single patient experienced an actual flashback following exposure to combat sounds, exhibiting tearfulness, diaphoresis, tachypnea, and severe agitation. Results from his SPECT study demonstrated a dramatically altered ratio of cortical to subcortical perfusion during the flashback but not during the control scan. This altered pattern, which showed a peak of activity in the thalamus, was not consistent with global rCBF changes induced by hyperventilation. The perfusion pattern during the patient's control scan was qualitatively indistinguishable from any of the SPECT scans obtained for the other patients. This single case suggests a possible role for corticothalamic dysfunction in flashbacks. Depression and Anxiety 4:146–150, 1996/1997. © 1997 Wiley-Liss, Inc.

Biological predictors of suicidality in schizophrenia

Abstract: The objective of this study was to determine whether polysomnographic rapid eye movement (REM) sleep abnormalities and cortisol response to the dexamethasone suppression test (DST) differentiate between schizophrenic patients with and without a history of suicidal behaviour. We assessed a sample of 96 schizophrenic in-patients at the end of a 2-week medication-free period with the DST, polysomnography, and an extensive clinical assessment battery. Patients exhibiting suicidal behaviour were significantly more likely to have increased total REM time and increased total REM activity. We found no significant relationship between suicidal behaviour and DST non-suppression. This study confirms a previous finding suggesting an association between REM sleep abnormalities and suicidal behaviour in schizophrenia. It is postulated that this observed association may be related to serotonergic dysfunction in schizophrenia.