Symptom Patterns Following NMDA Antagonist Administration

1 Symptom Patterns Following NMDA Antagonist Administration 

In initial studies with PCP and ketamine in the early 1960s, it was noted that both agents produced what would now be considered positive, negative, and cognitive symptoms of schizophrenia (Luby et al., 1962 Javitt and Zukin, 1991). Similar results were observed in the clinical studies of PCP abusers in the early 1980s. 

Symptomatic effects of NMDA blockade were better classified starting in the early 1990s in a series of ketamine challenge studies conducted in both normal volunteers and schizophrenia patients. In normal volunteers, significant increases in positive, negative, and cognitive symptoms were observed in schizophrenia, using scales such as the PANSS or BPRS/SANS. 

A potentially informative difference between ketamine-induced symptoms and those of schizophrenia is in the production of hallucinations. Thus, in established schizophrenia, auditory hallucinations consisting of voices of various types are common, whereas visual hallucinations are rare. In contrast, during ketamine-induced psychosis, visual perceptual distortions are common but organized auditory 

Data for controls and double-blind, placebo controlled crossover unless otherwise noted Neuropsychology 

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