PT  - JOURNAL ARTICLE
AU  - Amit Kumar
AU  - Oded Schiff
AU  - Edi Barkai
AU  - Bartlett W. Mel
AU  - Alon Poleg-Polsky
AU  - Jackie Schiller
TI  - NMDA spikes mediate amplification of odor pathway information in the piriform cortex
AID  - 10.1101/346791
DP  - 2018 Jan 01
TA  - bioRxiv
PG  - 346791
4099  - http://biorxiv.org/content/early/2018/06/13/346791.short
4100  - http://biorxiv.org/content/early/2018/06/13/346791.full
AB  - The piriform cortex (PCx) receives direct input from the olfactory bulb (OB) and is the brain’s main station for odor recognition and memory. The transformation of the odor code from OB to PCx is profound: mitral and tufted cells in olfactory glomeruli respond to individual odorant molecules, whereas pyramidal neurons (PNs) in the PCx responds to multiple, apparently random combinations of activated glomeruli. How these “discontinuous” receptive fields are formed from OB inputs remains unknown. Counter to the prevailing view that olfactory PNs sum their inputs passively, we show for the first time that NMDA spikes within individual dendrites can both amplify OB inputs and impose combination selectivity upon them, while their ability to compartmentalize voltage signals allows different dendrites to represent different odorant combinations. Thus, the 2-layer integrative behavior of olfactory PN dendrites provides a parsimonious account for the nonlinear remapping of the odor code from bulb to cortex.