Reduced auditory evoked gamma band response and cognitive processing deficits in first episode schizophrenia

TY - JOUR

T1 - Reduced auditory evoked gamma band response and cognitive processing deficits in first episode schizophrenia

AU - Leicht, Gregor

AU - Andreou, Christina

AU - Polomac, Nenad

AU - Lanig, Clarissa

AU - Schöttle, Daniel

AU - Lambert, Martin

AU - Mulert, Christoph

PY - 2015/3/16

Y1 - 2015/3/16

N2 - OBJECTIVES: Gamma-band oscillations (e.g., the early auditory evoked gamma-band response, aeGBR) have been suggested to mediate cognitive and perceptual processes by driving the synchronization of local neuronal populations. Reduced aeGBR is a consistent finding in patients with schizophrenia and high-risk subjects, and has been proposed to represent an endophenotype for the illness. However, it is still unclear whether this reduction represents a deficit in sensory or cognitive processes, or a combination of the two. The present study investigated this question by manipulating the difficulty of an auditory reaction task in patients with first-episode schizophrenia and healthy controls.METHODS: A 64-channel EEG was recorded in 23 patients with first-episode schizophrenia and 22 healthy controls during two conditions of an auditory reaction task: an easy condition that merely required low-level vigilance, and a difficult condition that placed significant demands on attention and working memory.RESULTS: In contrast to healthy controls, patients failed to increase aeGBR power and phase-locking in the difficult condition. In patients, aeGBR power and phase-locking indices were associated with working memory deficits.CONCLUSIONS: The observed results confirm the applicability of aeGBR disturbances as a stable endophenotype of schizophrenia, and suggest a cognitive, rather than sensory, deficit at their origin.

AB - OBJECTIVES: Gamma-band oscillations (e.g., the early auditory evoked gamma-band response, aeGBR) have been suggested to mediate cognitive and perceptual processes by driving the synchronization of local neuronal populations. Reduced aeGBR is a consistent finding in patients with schizophrenia and high-risk subjects, and has been proposed to represent an endophenotype for the illness. However, it is still unclear whether this reduction represents a deficit in sensory or cognitive processes, or a combination of the two. The present study investigated this question by manipulating the difficulty of an auditory reaction task in patients with first-episode schizophrenia and healthy controls.METHODS: A 64-channel EEG was recorded in 23 patients with first-episode schizophrenia and 22 healthy controls during two conditions of an auditory reaction task: an easy condition that merely required low-level vigilance, and a difficult condition that placed significant demands on attention and working memory.RESULTS: In contrast to healthy controls, patients failed to increase aeGBR power and phase-locking in the difficult condition. In patients, aeGBR power and phase-locking indices were associated with working memory deficits.CONCLUSIONS: The observed results confirm the applicability of aeGBR disturbances as a stable endophenotype of schizophrenia, and suggest a cognitive, rather than sensory, deficit at their origin.

U2 - 10.3109/15622975.2015.1017605

DO - 10.3109/15622975.2015.1017605

M3 - SCORING: Journal article

C2 - 25774562

VL - 16

SP - 387

EP - 397

JO - WORLD J BIOL PSYCHIA

JF - WORLD J BIOL PSYCHIA

SN - 1562-2975

IS - 6

ER -