TY - JOUR T1 - Dynamics of Cortical Dendritic Membrane Potential and Spikes in Freely Behaving Rats JF - bioRxiv DO - 10.1101/096941 SP - 096941 AU - Jason J. Moore AU - Pascal M. Ravassard AU - David Ho AU - Lavanya Acharya AU - Ashley L. Kees AU - Cliff Vuong AU - Mayank R. Mehta Y1 - 2016/01/01 UR - http://biorxiv.org/content/early/2016/12/28/096941.abstract N2 - Neural activity in vivo is primarily measured using extracellular somatic spikes, which provide limited information about neural computation. Hence, it is necessary to record from neuronal dendrites, which generate dendritic action potentials (DAP) and profoundly influence neural computation and plasticity. We measured neocortical sub- and supra-threshold dendritic membrane potential (DMP) from putative distal-most dendrites using tetrodes in freely behaving rats over multiple days with a high degree of stability and sub-millisecond temporal resolution. DAP firing rates were several fold larger than somatic rates. DAP rates were modulated by subthreshold DMP fluctuations which were far larger than DAP amplitude, indicting hybrid, analog-digital coding in the dendrites. Parietal DAP and DMP exhibited egocentric spatial maps comparable to pyramidal neurons. These results have important implications for neural coding and plasticity.One Sentence Summary Measurement of cortical dendritic membrane potential for several days in freely behaving rats reveals disproportionate dendritic spiking and analog and digital coding. ER -