BLOG

Share 0
Like 0
Basic properties of somatosensory-evoked responses in the dorsal hippocampus of the rat.

Basic properties of somatosensory-evoked responses in the dorsal hippocampus of the rat.

We investigate the elementary responses of the hippocampus to somatosensory stimulation
(peripheral and lemniscal) in rats given its relevance for episodic memory function
In our recent paper in J.Physiol, we used electrical stimulation of the paws, the whisker pad or the medial lemniscus to probe the somatosensory pathway to the hippocampus in the anesthetized rat, and multisite electrodes in combination with tetrode and intracellular recordings to look at the properties of somatosensory hippocampal responses. We found that peripheral and lemniscal stimulation elicited small local field potential responses in the dorsal hippocampus about 35-40 ms post-stimulus. We applied CSD analysis to reveal associated synaptic sinks and sources at different hippocampal layers, and tetrode, multi-unit and intracellular data to demostrate that somatosensory signals reach the hippocampus mainly from layer II entorhinal cortex to directly discharge dentate gyrus granule cells, while a different predominantly inhibitory process takes place in CA1. Our data reveal a distinct organization of somatosensory-related extra-hippocampal inputs converging onto DG and CA1.
Share 0
Like 0