As time passes after an initial learning experience, our memories do not remain perfectly unchanged. They may become more durable, may gradually lose their level of precision and detail, or may become incorporated into existing knowledge structures that inform and constrain our understanding of the world around us. These changes, in turn, are thought to be accompanied by transformations in how such memories are represented in the brain, both in the medial temporal lobe and the surrounding cortex.
Although our lives unfold continuously across time, we often remember our experiences as sequences of discrete events. How, then, do we derive structure from this constant stream of information? What neural and behavioral mechanisms might support our ability to organize, bind, or segment our everyday experiences into meaningful mnemonic events?
Hippocampal memory circuits have been strongly implicated in the formation and persistence of delusions in psychological disorders such as schizophrenia. According to one hypothesis, delusions may result from aberrant associative memory formation, and then may persist due to a failure to update false beliefs with new episodic information. To consider these hypotheses, we are investigating encoding and memory-based predictions in subjects with first episode psychosis both before and after they begin medication.