Cortical parvalbumin interneurons and cognitive dysfunction in schizophrenia.

Translational Neuroscience Program, Department of Psychiatry, University of Pittsburgh, Pittsburgh, PA 15213, USA.
Trends in Neurosciences (Impact Factor: 12.9). 12/2011; 35(1):57-67. DOI: 10.1016/j.tins.2011.10.004
Source: PubMed

ABSTRACT Deficits in cognitive control, a core disturbance of schizophrenia, appear to emerge from impaired prefrontal gamma oscillations. Cortical gamma oscillations require strong inhibitory inputs to pyramidal neurons from the parvalbumin basket cell (PVBC) class of GABAergic neurons. Recent findings indicate that schizophrenia is associated with multiple pre- and postsynaptic abnormalities in PVBCs, each of which weakens their inhibitory control of pyramidal cells. These findings suggest a new model of cortical dysfunction in schizophrenia in which PVBC inhibition is decreased to compensate for an upstream deficit in pyramidal cell excitation. This compensation is thought to rebalance cortical excitation and inhibition, but at a level insufficient to generate the gamma oscillation power required for high levels of cognitive control.

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