Neural representation of object memory in the hippocampal formation

This project will create and implement a new translational animal test for object memory using stimulus sets in an operant chamber that will be developed from validated human ratings. We will then use this task to probe for the first time how object memory is encoded at the neural level when object information is presented either as a 2D image in the touchscreen chamber or as a 3D physical object in an open arena. This is important because whilst we have very good data from human fMRI experiments about how object memory is encoded in the brain this approach provides an indirect measure of neural function, indexed via changes in regional metabolic demand. Recording of neural responses is a well-established technique in rats and mice, but investigation of how neurones encode object memory is severely limited in terms of both number of studies and experimental approach. In addition, there has been no investigation of whether rat neurones process and represent 2D and 3D stimuli in similar ways to humans. Our comparison of neural responses to information via a touchscreen (2D; fully translatable to human studies) and in an open arena (3D) will provide vital and novel insights into the presentation of object information in both cases AND how neurones can distinguish between objects with high or low similarity.