Executive Functioning Component Mechanisms and Schizophrenia

Background: Executive functioning refers to a set of processes involved in complex, goal-directed thought and behavior involving multiple brain regions (e.g., prefrontal cortex, parietal cortex, basal ganglia) and multiple neurotransmitters (e.g., dopamine, glutamate, γ-aminobutyric acid). People with schizophrenia exhibit executive functioning deficits that are associated with treatment-refractory aspects of the disorder. Although there is general consensus about what cognitive tasks involve executive functioning, there is disagreement about the specific cognitive mechanisms that comprise executive functioning. Methods: This article discusses a number of possible candidate executive functioning mechanisms and provides a summary of the consensus reached by the executive functioning discussion group at the first CNTRICS (Cognitive Neuroscience for Treatment Research to Improve Cognition in Schizophrenia) meeting in Washington, DC. Results: The consensus was that two constructs have a well-founded basis in basic cognitive neuroscience research and seem to be impaired in schizophrenia: 1) rule generation and selection; and 2) dynamic adjustments in control (i.e., after conflict and errors). Conclusions: The consensus of the first CNTRICS meeting was that immediate translation of measures of these constructs for use in schizophrenia should be pursued. A number of other constructs (e.g., scheduling, sequencing) could also be very important for schizophrenia and are in need of more basic and more clinical research.