This project combines neuropsychological, neuroimaging, and eye tracking approaches in order to study the functional interactions of PFC and the hippocampus in supporting richly conditional behavior in humans. The experiments test our hypothesis that the hippocampus is critically involved in relational memory representations whereas PFC is involved in more abstract context-guided associative rules. Neuropsychological studies will provide evidence about the necessity of PFC and MTL regions in relational memory and context-dependent associations, and neuroimaging studies will provide evidence about the nature and timing of functional interactions between these regions. For each study, performance assessments will include not only explicit behavioral judgments but also eye movement-based assessment of memory, pioneered in our laboratory. This approach affords sensitive, implicit nr>easures of the strength of relational and context-dependent representations, based on preferential viewing patterns, as they change dynamically during each trial and across learning and retention. Experiments start with a "base" task in common with all the other empirical projects of the Center, and then graduate to more elaborate variants that systematically manipulate the amount and complexity of relational information or the complexity and abstractness of the context-dependent associative rules to be learned, in order to better determine the dependency of each of these aspects of memory on PFC, hippocampus, and their functional interactions, and further, on the directionality of their interactions.
Understanding the roles of PFC and MTL, and their interactions has clear health relevance. Dysfunction of PFC and/or MTL is implicated in a range of mental health disorders, including schizophrenia, bipolar disease, ADHD, cognitive aging. Alzheimer's disease, and drug addiction. Moreover, recent theorizing about these disorders have suggested a conceptualization of them as involving network dysfunction, including dysfunction in PFC-MTL interactions.
|Rueckemann, Jon W; DiMauro, Audrey J; Rangel, Lara M et al. (2016) Transient optogenetic inactivation of the medial entorhinal cortex biases the active population of hippocampal neurons. Hippocampus 26:246-60|
|Ryals, Anthony J; Rogers, Lynn M; Gross, Evan Z et al. (2016) Associative Recognition Memory Awareness Improved by Theta-Burst Stimulation of Frontopolar Cortex. Cereb Cortex 26:1200-10|
|Place, Ryan; Farovik, Anja; Brockmann, Marco et al. (2016) Bidirectional prefrontal-hippocampal interactions support context-guided memory. Nat Neurosci 19:992-4|
|Keene, Christopher S; Bladon, John; McKenzie, Sam et al. (2016) Complementary Functional Organization of Neuronal Activity Patterns in the Perirhinal, Lateral Entorhinal, and Medial Entorhinal Cortices. J Neurosci 36:3660-75|
|Eichenbaum, Howard (2016) Still searching for the engram. Learn Behav 44:209-22|
|McKenzie, Sam; Keene, Christopher S; Farovik, Anja et al. (2016) Representation of memories in the cortical-hippocampal system: Results from the application of population similarity analyses. Neurobiol Learn Mem 134 Pt A:178-91|
|Chen, Zetao; Lowry, Stephanie; Jacobson, Adam et al. (2015) Bio-inspired homogeneous multi-scale place recognition. Neural Netw 72:48-61|
|Wang, Jane X; Voss, Joel L (2015) Long-lasting enhancements of memory and hippocampal-cortical functional connectivity following multiple-day targeted noninvasive stimulation. Hippocampus 25:877-83|
|Howard, Marc W; Eichenbaum, Howard (2015) Time and space in the hippocampus. Brain Res 1621:345-54|
|Puig, M Victoria; Miller, Earl K (2015) Neural Substrates of Dopamine D2 Receptor Modulated Executive Functions in the Monkey Prefrontal Cortex. Cereb Cortex 25:2980-7|
Showing the most recent 10 out of 55 publications