Archives of general psychiatry
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Arch. Gen. Psychiatry · Apr 2008
Comparative StudyComparing drug-related hospital morbidity following heroin dependence treatment with methadone maintenance or naltrexone implantation.
Most research on heroin dependence treatments assesses short-term changes in patients' self-reported drug use. To our knowledge, long-term sustainability of changes in patients' drug use and associated hospital morbidity posttreatment have not been studied. ⋯ Naltrexone implants, but not methadone maintenance, has long-term benefits in reducing opioid-related hospital morbidity. However, long-lasting and increased nonopioid drug-related morbidity following naltrexone implantation is particularly concerning. Similar studies are required to confirm these findings.
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Arch. Gen. Psychiatry · Feb 2008
Randomized Controlled TrialGlutamate and the neural basis of the subjective effects of ketamine: a pharmaco-magnetic resonance imaging study.
Ketamine evokes psychosislike symptoms, and its primary action is to impair N-methyl-D-aspartate glutamate receptor neurotransmission, but it also induces secondary increases in glutamate release. ⋯ These 2 changes may underpin 2 fundamental processes of psychosis: abnormal perceptual experiences and impaired cognitive-emotional evaluation of their significance. The results are compatible with the theory that the neural and subjective effects of ketamine involve increased glutamate release.
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Arch. Gen. Psychiatry · Feb 2008
Controlled Clinical TrialPlacebo and nocebo effects are defined by opposite opioid and dopaminergic responses.
Placebo and nocebo effects, the therapeutic and adverse effects, respectively, of inert substances or sham procedures, represent serious confounds in the evaluation of therapeutic interventions. They are also an example of cognitive processes, particularly expectations, capable of influencing physiology. ⋯ Placebo and nocebo effects are associated with opposite responses of DA and endogenous opioid neurotransmission in a distributed network of regions. The brain areas involved in these phenomena form part of the circuit typically implicated in reward responses and motivated behavior.
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Arch. Gen. Psychiatry · Jan 2008
Neural substrates of symptoms of depression following concussion in male athletes with persisting postconcussion symptoms.
Depressed mood is frequently reported by individuals who have sustained cerebral concussion but little is known about the nature of this alteration in mood state. ⋯ The results suggest that depressed mood following a concussion may reflect an underlying pathophysiology consistent with a limbic-frontal model of depression. Given that depression is associated with considerable functional disability, this finding has important clinical implications for the management of individuals with a cerebral concussion.