Biological psychiatry
-
Biological psychiatry · Feb 2004
Mu-opioid receptor binding measured by [11C]carfentanil positron emission tomography is related to craving and mood in alcohol dependence.
The endogenous opioid system has been linked to alcohol dependence through animal and human studies. We investigated the relationship between alcohol craving and brain mu opioid receptors (mu-OR) in alcohol-dependent subjects. ⋯ Results show a strong functional relationship between alcohol craving, mood, and mu-OR binding in specific brain regions of recently abstinent, alcohol-dependent men.
-
Biological psychiatry · Feb 2004
Functional connectivity of the prefrontal cortex and the amygdala in posttraumatic stress disorder.
Persistent, intrusive re-experiencing in posttraumatic stress disorder (PTSD) is commonly construed as a failure of cingulate inhibition (i.e., extinction) over a hyperresponsive amygdala, based primarily on animal research of fear conditioning and the finding of cingulate hypoperfusion in PTSD. ⋯ These patterns might represent excessive influences of the amygdala over regions involved in autonomic, and higher-order visual memory processing in PTSD. The present data suggest that inferences of direct correspondence between animal studies and pathophysiology of PTSD should be made with caution.
-
Biological psychiatry · Nov 2003
Comparative StudySleep pathophysiology in posttraumatic stress disorder and idiopathic nightmare sufferers.
Nightmares are common in posttraumatic stress disorder (PTSD), but they also frequently occur in idiopathic form. Findings associated with sleep disturbances in these two groups have been inconsistent, and sparse for idiopathic nightmares. The aim of the present study was to investigate whether sleep anomalies in PTSD sufferers with frequent nightmares (P-NM) differ from those observed in non-PTSD, idiopathic nightmare (I-NM) sufferers and healthy individuals. ⋯ Posttraumatic nightmare sufferers exhibit more nocturnal awakenings than do I-NM sufferers and control subjects, which supports the hypothesis of hyperarousal in sleep in PTSD sufferers; however, elevated PLM indices in both P-NM and I-NM sufferers suggest that PLMs may not be a marker of hyperarousal in sleep of PTSD sufferers. Rather, PLMs may be a correlate of processes contributing to intense negative dreaming.
-
Biological psychiatry · Nov 2003
Comparative StudyForebrain-specific trkB-receptor knockout mice: behaviorally more hyperactive than "depressive".
According to the neurotrophin hypothesis of depression, decreased activity of brain-derived neurotrophic factor (BDNF) contributes to behavioral and plasticity-related alterations in depressed patients. We investigated the hypothesis that mice with a forebrain-specific knockout of the trkB receptor, the main mediator of BDNF signaling, represent a genetic animal model for depression. ⋯ trkB(CaMKII-CRE) mice cannot be regarded as a genetic mouse model of depression. Instead, the behavioral symptoms of trkB(CaMKII-CRE) mice, comprising hyper-locomotion, stereotyped behaviors, and cognitive impairments, are similar to those postulated for mouse models of attention-deficit disorder.