Effects of different subanesthetic doses of (S)-ketamine on neuropsychology, psychopathology, and state of consciousness in man.
This is the first neuropsychological study using the S-enantiomer of the noncompetitive N-methyl-D-aspartate antagonist ketamine. In 2 randomized placebo-controlled trials we studied effects of two different doses of (S)-ketamine (low dose/high dose) on neuropsychological functions and psychopathology in 12 healthy male volunteers. Impairment was measured via standardized neuropsychological tests. Results indicate that both subanaesthetic doses produce only nonsignificant impairment in most of the tasks. Tasks involving divided and sustained attention as well as scores for objective and subjective psychopathology show significant impairment in a dose-dependent manner. Implications of these findings for the neuropsychology of attention and schizophrenia are discussed.
Passie
Torsten
T
Department of Clinical Psychiatry and Psychotherapy, Medical School Hannover, Carl-Neuberg-Strasse 1, DE-30625 Hannover, Germany. dr.passie@gmx.de
Karst
Matthias
M
Wiese
Birgitt
B
Emrich
Hinderk M
HM
Schneider
Udo
U
D000328:Adult; D000700:Analgesics / Q000008:administration & dosage*; D000704:Analysis of Variance; D001288:Attention / Q000187:drug effects; D003243:Consciousness / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004334:Drug Administration Schedule; D006801:Humans; D007649:Ketamine / Q000008:administration & dosage*; D008297:Male; D009483:Neuropsychological Tests; D009484:Neuropsychology; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000187:drug effects; D011599:Psychopathology; D011930:Reaction Time / Q000187:drug effects; D017603:Signal Detection, Psychological / Q000187:drug effects; D011795:Surveys and Questionnaires
D000700:Analgesics; D007649:Ketamine