Human memory search: theory and data

The fundamental problem of episodic memory concerns linking items with their temporal context (during study) and retrieving the context associated with items (during recall). The reinstatement of mental context is distinguished from the idea that remembering solely involves a reactivation of content information that is specific to that event. I will first present behavioral evidence for the idea associations in episodic memory arise from this contextual encoding/retrieval process, and that forgetting largely reflects the loss of effective contextual cues at retrieval. I will describe how the Context Maintenance and Retrieval model (Polyn et al., 2009)---a computational model of episodic memory---can account for these data, along with data on the role of semantic and source information in memory retrieval. I will then show how direct brain recordings taken as neurosurgical patients perform a free recall task can be used to test some of these ideas. Finally, I will discuss the challenges and rewards of attempting to relate neurophysiological and cognitive approaches to the study of human memory.