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Perceptual organization in ketamine users: preliminary evidence of deficits on night of drug use but

Perceptual organization in ketamine users: preliminary evidence of deficits on night of drug use but

  1. Jatelka
    Journal of Psychopharmacology 2007 May;21(3):347-52

    Uhlhaas PJ (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Millard I (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Muetzelfeldt L (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Curran HV (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus), Morgan CJ (http://www.ncbi.nlm.nih.gov/sites/e...l.Pubmed_DiscoveryPanel.Pubmed_RVAbstractPlus).

    N-methyl-D-aspartate (NMDA)-receptor antagonists such as ketamine can induce transient schizophrenia-like symptoms and cognitive dysfunctions in healthy volunteers similar to those observed in patients with schizophrenia. Perceptual organization deficits have been documented in schizophrenia and are thought to be related to some symptoms associated with the illness. The current study was designed to determine whether people who repeatedly self-administer ketamine would also show deficits in perceptual organization. Using a psychophysically well-controlled measure of contour integration, we compared a group of recreational users (n = 16) to a group of poly-drug using controls (n = 16). Contour integration performance was measured on the night of drug use and 3 days later when drug free. The results showed that on the night of drug use, ketamine produced a dysfunction in contour integration however, this was not present 3 days later when drug free. Levels of dissociation were also higher in ketamine users only on the night of drug use. These preliminary data provide some support for the role of NMDA-receptor hypofunctioning in dysfunctional coordination of cognitive activity.

Recent Reviews

  1. enquirewithin
    Version: 2008-07-06
    The article is interesting, although it seems to be following the old 'psychomimetic' approach, which was given up with regard to psychedelics a long time ago. Some chronic ketamine users have been categorised as showing symptoms of 'paranoid schizophrenia' but, as this study show, the symptoms disappear within days of abstinence from the drug.