Successful interaction with the world depends on how well we are able to adjust our ongoing behavior to meet the contextual and situational demands. On-line adjustments of behavior require a certain degree of self and response monitoring. Individuals with psychosis are thought to be impaired in their ability to monitor, inhibit and control ongoing behavior.

To study control of action, we examine response monitoring in schizophrenia and bipolar disorder with the countermanding paradigm (stop signal reaction time task). To learn more about this project, please go to Katy Thakkar's website.

To study control of mental representations, a series of experiments involving mental rotation, perspective-taking and simulation are currently in progress. The ability to mentally transform visuospatial perspectives and internally simulate external events may be very important for understanding the social world. (see Neurocognitive origins of social deficits)

Control of action and mental representation also depend on internally stored regularities and predictions. We appear to have an implicit understanding of probabilities of events in the world, which we use to guide our behavior. But it is unclear how we come to acquire these probabilities. One possibility is that working memory and long-term memory interactively glue sequential events over time. We are examining how healthy individuals and psychosis patients deduce probabilities of simple events over time. Some people need to accumulate a lot of data whereas others jump to conclusion with very little evidence. Again, individual differences interact with cognitive machinery in complex ways.