Biology subjects

Lee, A. C. H.

Publications and source records attributed to Lee, A. C. H..

2 recordsLinked to original sources

bioRxiv2017

Ventral hippocampal CA1 and CA3 differentially mediate learned approach-avoidance conflict processing

The ventral hippocampus is thought to play a key role in the resolution of approach-avoidance conflict, a scenario that arises when stimuli with opposing valences are present simultaneously. Little is known, however, about the contributions of specific hippocampal sub-regions in this process, a critical issue given the functional and anatomical heterogeneity of this structure. Using a non-spatial cue-based paradigm in rats, we found that transient pharmacological inactivation of ventral CA1 produced an avoidance of a conflict cue imbued with both learned positive and negative outcomes, whereas inactivation of the ventral CA3 resulted in the opposite pattern of behavior, with significant preference for the conflict cue. In contrast, dorsal CA1- and CA3-inactivated rats showed no change in conflict behavior. Our findings provide important insight into the functions and circuitry of the ventral hippocampus by demonstrating that the ventral CA1 and CA3 subserve distinct and opposing roles in approach-avoidance conflict processing.

neuroscience↗

bioRxiv2017

Memory And Perception-based Facial Image Reconstruction

Visual memory for faces has been extensively researched, especially regarding the main factors that influence face memorability. However, what we remember exactly about a face, namely, the pictorial content of visual memory, remains largely unclear. The current work aims to elucidate this issue by reconstructing face images from both perceptual and memory-based behavioural data. Specifically, our work builds upon and further validates the hypothesis that visual memory and perception share a common representational basis underlying facial identity recognition. To this end, we derived facial features directly from perceptual data and then used such features for image reconstruction separately from perception and memory data. Successful levels of reconstruction were achieved in both cases for newly-learned faces as well as for familiar faces retrieved from long-term memory. Theoretically, this work provides insights into the content of memory-based representations while, practically, it opens the path to novel applications, such as computer-based sketch artists.

neuroscience↗