Thursday, October 21, 2004

12 noon

Redwood Neuroscience Institute


Title "A neural model of spatial memory, mental imagery and mental navigation."


Sue Becker

Professor of Psychology

McMaster University



In this talk, I will describe a computational model of the neural mechanisms in the parietal and temporal lobes that support spatial navigation, imagery, and episodic recall. Long-term allocentric representations of scenes are stored in the hippocampus and associated with object and landmark information in the surrounding medial temporal lobe.  Viewpoint-dependent representations are generated in the parietal part of the model to enable construction of an imagined retinotopic scene and generation of appropriate body movements.  Bidirectional interactions between the hippocampal and parietal modules allow translation between allocentric and egocentric representations, with dynamical interactions between recalled episodic memories and viewer-centered mental images.  Damage to the parietal part of the model produces symptoms of hemispatial neglect, including neglect in mental imagery that rotates with the imagined perspective of the observer as observed in parietally lesioned individuals. Finally, through egomotion-driven parietal circuits, the model simulates mental navigation.


This is joint work with Neil Burgess at UCL.