Clarifying the functional process represented by reduced P50 suppression in schizophrenia

P50 suppression is a measure of the brain’s ability to modulate its response to incoming repetitive auditory stimuli that is derived from the electroencephalogram. This measure is widely used in psychiatric research and is argued to be a schizophrenia endophenotype. However, inconsistent results within this literature suggest that P50 suppression, even in healthy populations, is poorly understood and limits the ‘endophenotype’ claim. An understanding of methodological issues relevant to P50 suppression measurement, variables influencing P50 suppression, and the neural function it indexes in healthy subjects will inform psychiatric research as to the nature of impairments observed in schizophrenia.