Laminar organization of encoding and memory reactivation in the parietal cortex

Wilber, A.; Skelin, I.; McNaughton, B. L.

doi:10.1101/110684

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bioRxiv · 10.1101/110684

Laminar organization of encoding and memory reactivation in the parietal cortex

Wilber, A.·Skelin, I.·McNaughton, B. L.

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Abstract

Egocentric neural coding has been observed in parietal cortex (PC), but its topographical and laminar organization is not well characterized. We used multi-site recording to look for evidence of local clustering and laminar consistency of linear and angular velocity encoding in multi-neuronal spiking activity (MUA) and in the high-frequency (300-900 Hz) component of the local field potential (HF-LFP), believed to reflect local spiking activity. Rats were trained to run many trials on a large circular platform, either to LED-cued goal locations or as a spatial sequence from memory. Tuning to specific self-motion states was observed consistently, and exhibited distinct cortical depth-invariant coding properties. These patterns of collective local and laminar activation during behavior were reactivated in compressed form during post-experience sleep, and temporally coupled to hippocampal sharp wave ripples. Thus, PC neuron motion encoding is consistent across cortical laminae, and this consistency is maintained during memory reactivation.\n\nHighlights O_LIParietal cortex MUA encodes specific movements coherently across laminae.\nC_LIO_LIThis organizational scheme is maintained during subsequent memory reactivation\nC_LIO_LIMUA and HF-LFP showed similar self-motion tuning and memory reactivation dynamics\nC_LIO_LIThis establishes the utility of MUA and HF-LFP for human memory reactivation studies\nC_LI

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Wilber, A., Skelin, I., McNaughton, B. L.. 2017-02-25. Laminar organization of encoding and memory reactivation in the parietal cortex. https://doi.org/10.1101/110684

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