Acute Effects of Ketamine on Memory Systems and Psychotic Symptoms in Healthy Volunteers

@article{Morgan2004AcuteEO,
  title={Acute Effects of Ketamine on Memory Systems and Psychotic Symptoms in Healthy Volunteers},
  author={C. Morgan and Ali Mofeez and B. Brandner and L. Bromley and H. Curran},
  journal={Neuropsychopharmacology},
  year={2004},
  volume={29},
  pages={208-218}
}
N-methyl-D-aspartate (NMDA) receptor antagonists have been demonstrated to induce schizophrenia-like symptoms and cognitive impairment in humans. The NMDA receptor has been strongly implicated in memory, but research to date on the effects of NMDA antagonists has examined only some aspects of human memory functions. This study used a double-blind, placebo-controlled, independent groups design with 54 healthy volunteers to examine the effects of infusions of two doses (0.4, 0.8 mg/kg) of the… Expand
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References

SHOWING 1-10 OF 48 REFERENCES
NMDA Receptor Function and Human Cognition: The Effects of Ketamine in Healthy Volunteers
TLDR
The effects of subanesthetic doses of ketamine on two forms of memory, free recall and recognition, as well as attention and behavior in 15 healthy volunteers are examined, suggesting that the NMDA receptor plays a direct role in two types of explicit memory. Expand
Ketamine-Induced NMDA Receptor Hypofunction as a Model of Memory Impairment and Psychosis
TLDR
This double-blind, placebo-controlled, randomized, within-subjects comparison of three fixed subanesthetic, steady-state doses of intravenous ketamine in healthy males demonstrated dose-dependent increases in Brief Psychiatric Rating Scale positive and negative symptoms. Expand
Effects of Ketamine on Thought Disorder, Working Memory, and Semantic Memory in Healthy Volunteers
TLDR
This study characterizes the formal thought disorder associated with ketamine and may suggest that ketamine-induced deficits in working memory are associated withketamine- induced thought disorder. Expand
Ketamine impairs response inhibition and is positively reinforcing in healthy volunteers: a dose–response study
TLDR
The lack of residual effects in healthy volunteers on day-3 indicates that impairments found on day 3 in ketamine abusers are chronic effects, and the abuse of ketamine may be related to its capacity both to reinforce and to decrease response inhibition. Expand
Effect of a subanesthetic dose of ketamine on memory and conscious awareness in healthy volunteers
TLDR
Ketamine decreases episodic memory performance by impairing encoding, but not retrieval processes, and does not selectively impair subjective states of awareness associated with recognition memory as it has been seen in patients with schizophrenia. Expand
The effects of sub-anaesthetic doses of ketamine on memory, cognitive performance and subjective experience in healthy volunteers
TLDR
Low doses of ketamine had selective, dose-related effects on memory, perceptual and psychomotor functions, and the disruption of memory and perceptual processes may help to explain the unique subjective state induced by ketamine. Expand
Association of ketamine-induced psychosis with focal activation of the prefrontal cortex in healthy volunteers.
TLDR
Data suggest that the prefrontal cortex may be involved in mediating NMDA receptor-induced psychosis, and a change in one psychotic symptom, conceptual disorganization, was significantly related to prefrontal activation. Expand
Cognitive, dissociative and psychotogenic effects of ketamine in recreational users on the night of drug use and 3 days later.
TLDR
Ketamine appears to induce acute and severe impairments of working, episodic and semantic memory as well as psychotogenic and dissociative effects and schizotypal symptomatology. Expand
Therapeutic Implications of the Hyperglutamatergic Effects of NMDA Antagonists
Antagonists of the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor produce transient effects in healthy human subjects that resemble symptoms observed in some schizophrenic patients. NMDAExpand
Interactive effects of subanesthetic ketamine and subhypnotic lorazepam in humans
TLDR
Data suggest that subhypnotic lorazepam and ketamine show a spectrum of interactive effects, ranging from antagonism to potentiation. Expand
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