Biological psychiatry
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Biological psychiatry · Nov 2003
Comparative StudyRecovery and chronicity in anorexia nervosa: brain activity associated with differential outcomes.
The course of anorexia nervosa varies from rapid recovery to a chronic debilitating illness. This study aimed to identify functional neural correlates associated with differential outcomes. ⋯ Separate neural correlates underlie trait and state characteristics of anorexia nervosa. The medial prefrontal response to disease-specific stimuli may be related to trait vulnerability. Lateral and apical prefrontal involvement is associated with a good outcome.
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Biological psychiatry · Oct 2003
Randomized Controlled Trial Clinical TrialIntensity-dependent regional cerebral blood flow during 1-Hz repetitive transcranial magnetic stimulation (rTMS) in healthy volunteers studied with H215O positron emission tomography: II. Effects of prefrontal cortex rTMS.
The changes in brain activity produced by repetitive transcranial magnetic stimulation (rTMS) of the prefrontal cortex (PFC) remain unclear. We examined intensity-related changes in brain activity with positron emission tomography (PET) in normal volunteers during rTMS delivered to the left PFC. ⋯ The intensity-related inverse relationship between 1-Hz rTMS and prefrontal activity appears opposite to that seen with rTMS over the motor cortex in a companion study. Intensity-dependent increases in rCBF were seen in a number of distant cortical and subcortical areas with PFC rTMS, suggesting activation of left anterior cingulate, claustrum, and cerebellum. The regional differences in direction of rTMS effects and the greater activation of distant structures at higher intensities suggest the potential importance of higher-intensity prefrontal rTMS for therapeutic applications in neuropsychiatric patients.
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Biological psychiatry · Dec 2002
Comparative StudyBrain structures in pediatric maltreatment-related posttraumatic stress disorder: a sociodemographically matched study.
Previous investigations suggest that maltreated children evidence alterations of chemical mediators of stress and adverse brain development. Previous anatomical magnetic resonance imaging (MRI) brain studies have not controlled for socioeconomic status. ⋯ These data provide further evidence to suggest that maltreatment-related PTSD is associated with adverse brain development. These data also suggest that male children may be more vulnerable to these effects.
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Biological psychiatry · Jun 2002
Editorial CommentAnother view of therapy for cognition in schizophrenia.
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Biological psychiatry · Jun 2002
Associative learning deficits increase symptoms of anxiety in humans.
Unpredictability has been postulated to be fundamental to anxiety and mood disorders. The origin of this unpredictability remains obscure. Because classical conditioning promotes predictability, this study investigated whether failure to learn conditioned stimulus (CS)-unconditioned stimulus (US) relationship during fear conditioning increased anxiety and avoidance. ⋯ Deficits in explicit cue fear conditioning can enhance anxiety. These findings are consistent with theories that associate anxiety and mood disorders with perceived unpredictability. Contextual conditioning models may be relevant to study chronic forms of anxiety.