Long-range cortico-hippocampal circuit interactions in shaping dendritic spikes, plasticity and sensory-spatial representation.
Please join us for an exceptional seminar this coming Monday May 15th at Noon.
It will be at the newly opened Center of Psychiatry and Neuroscience (102-108 rue de la santé, 75014 Paris)
4th Floor Conference room
Jayeeta BASU, PhD
Assistant Professor
Neuroscience Institute
New York University School of Medicine
Long-range cortico-hippocampal circuit interactions in shaping dendritic spikes, plasticity and sensory-spatial representation.
The circuit mechanisms shaping context-dependent representation of the sensory environment is not well understood. We have recently characterized the functional role of long-range GABAergic projection inputs from the entorhinal cortex to CA1 that may be relevant for assigning contextual salience to coincident sensory stimuli (Basu et al. 2016) . These GABAergic inputs are important for gating dendritic spike activity and are necessary for induction of input timing dependent plasticity. Behaviorally silencing inhibition from lateral entorhinal cortex locally in CA1 impairs precision of contextual fear and object recognition memory suggesting a role in pattern separation. The CA3 sub-region of hippocampus is unique in that it performs computations resulting in context dependent pattern completion and separation. Long-range inhibitory inputs from both medial and lateral entorhinal cortices to CA3 are dense. We have developed an in vivo head-fixed imaging paradigm to examine pattern separation and completion based population dynamics at cellular and sub-cellular resolution in CA3. In this task mice are exposed to a wide range of contexts where the differences in the multisensory stimuli between each context is gradually varied to different degrees. Under these conditions we are testing how manipulation of long-range inhibitory projections from entorhinal cortex modulates the balance between stability and remapping based plasticity of spatially tuned sequences of CA3 pyramidal neurons.
