Psychiatric hospitalization and veterans with traumatic brain injury: a retrospective study.

Objective: To determine risk factors for psychiatric hospitalization after traumatic brain injury (TBI) in veterans. SUBJECTS AND PROCEDURES: Medical records of 96 veterans with histories of TBI (17 mild, 33 moderate, and 46 severe) were reviewed for information concerning psychiatric history, including hospitalization and substance misuse.

Results: Subjects with a history of problematic drug and alcohol use had a significantly higher probability of psychiatric hospitalization than those without such a history.

Improved p50 auditory gating with ondansetron in medicated schizophrenia patients.

Objective: Most schizophrenia patients have a deficit in auditory sensory gating, which appears to be mediated by the alpha-7 nicotinic receptor, that is not improved with conventional antipsychotic treatment. This study examined the effects of ondansetron, a highly selective 5-HT3 antagonist, on the P50 auditory evoked potential.

Method: Eight medicated outpatients with schizophrenia were given either ondansetron (16 mg) or placebo in a double-blind, placebo-controlled design.

Varied effects of atypical neuroleptics on P50 auditory gating in schizophrenia patients.

Objective: Sensory gating deficits found in schizophrenia can be assessed by using a paired auditory stimulus paradigm to measure auditory evoked response. The ratio of the P50 response amplitude of the second or test stimulus to that of the first or conditioning stimulus is expressed as a percentage. Normal subjects generally suppress the second response and typically have ratios of less than 40%.

Reversal of diminished inhibitory sensory gating in cocaine addicts by a nicotinic cholinergic mechanism.

Cocaine addiction, as with other stimulant abuse, produces psychotic symptoms. Although often moderate to mild in severity, these symptoms are, nevertheless, associated with poorer over-all outcome. Recent studies suggest diminished nicotinic cholinergic neurotransmission as a mechanism of a physiological deficit found in schizophrenia, failure of auditory sensory inhibition.

The P50 auditory event-evoked potential in adult attention-deficit disorder: comparison with schizophrenia.

Background: Attention-deficit/hyperactivity disorder (ADHD) and schizophrenia are both conceptualized as disorders of attention. Failure to inhibit the P50 auditory event-evoked response, extensively studied in schizophrenia, could also occur in ADHD patients, if these two illnesses have common underlying neurobiological substrates.

Methods: This study examined the inhibition of the P50 auditory event-evoked potential in 16 unmedicated adults with ADHD, 16 schizophrenic outpatients, and 16 normal control subjects.