Decoding signal processing in thalamo-hippocampal circuitry: implications for theories of memory and spatial processing.

Our latest paper, focusing on signals afferent to the hippocampal formation as determinants of hippocampal dynamics, and therefore memory and spatial cognition [download]. Brain Res. 2014 Dec 9. pii: S0006-8993(14)01672-2. doi:10.1016/j.brainres.2014.12.003. Decoding signal processing in thalamo-hippocampal circuitry: implications for theories of memory and spatial processing. Tsanov M, O׳Mara SM Highlights Thalamo-hippocampal projections are vital for episodic… Read More

Decoding signal processing in thalamo-hippocampal circuitry: implications for theories of memory and spatial processing

Decoding signal processing in thalamo-hippocampal circuitry: implications for theories of memory and spatial processing Marian Tsanov and Shane M. O’Mara Our latest paper. Highlights • Thalamo-hippocampal projections are vital for episodic memory formation. • There is extensive connectivity between these structures. • We examine the signals processed within this circuitry. • We focus on head… Read More

Neuroanatomical investigations of the projections of the Papez circuit, with an emphasis on connections to the diencephalon

The projections of the extended hippocampal formation are still to a surprising extent under-described and under-investigated, despite the Papez circuit having been first postulated in 1937.  James Papez originally proposed that “the hypothalamus, the anterior thalamic nuclei, the gyrus cinguli, the hippocampus and their interconnections constitute a harmonious mechanism which may elaborate the functions of central emotion,… Read More

Oscillatory entrainment of thalamic neurons by theta rhythm in freely moving rats.

Take-home message: The thalamus plays a key role in  learning and memory. However, the neurons of the anteroventral nucleus have not been characterised in vivo. Here, we provide a framework for the classification of neuron type, based on their electrophysiological phenotype, and show that many of these cells are theta-modulated (a strong 7-12 Hz oscillation in the EEG, studied most frequently in… Read More

Theta-modulated head direction cells in the rat anterior thalamus.

Take-home message – two key findings: (1) there are head-direction cells in the anteroventral thalamus (head direction cells fire when the head is pointed in a particular orientation); (2) a large fraction of these cells are theta-modulated (a strong 7-12 Hz oscillation in the EEG, studied most frequently in the hippocampal formation). These data are interesting because they suggests that the anterior thalamus… Read More

Hippocampal-anterior thalamic pathways for memory: uncovering a network of direct and indirect actions.

Our major theoretical take and review of the extended brain systems that support explicit, declarative memory in the brain. [Download the paper.] Take-home message: there’s a lot more to memory than the hippocampal formation, and you forget (!) the connected thalamic structures at your peril, because the anterior thalamus provides a subcortical circuit supporting memory and spatial… Read More