Mickey London - Robust and multi-modal adrenergic axonal responses predict cortical dendritic activity

You are cordially invited to a seminar of the

Dept. of Physiology and Pharmacology

Sackler Faculty of Medicine
 

By:

Mickey London

Hebrew University, ELSC

Robust and multi-modal adrenergic axonal responses predict cortical dendritic activity

The seminar will take place on Wednesday, April 21, 2021 | 13:00

Zoom link

https://us02web.zoom.us/j/8601950374

Abstract

The locus coeruleus axonal projections to the neocortex release norepinephrine (NE), a neuromodulator involved in cognitive functions such as attention, arousal, and working memory. Using two-photon Ca2+ imaging of NE axons in the cortex of awake mice, we discovered that NE axons in the primary somatosensory cortex responded robustly and reliably to somatosensory stimulation. Interestingly, NE axons also responded to stimuli of other modalities (auditory and visual). These results indicate that responses of NE axons to sensory stimuli provide a robust multi-modal signal. However, despite the robustness, we found consistent variations in the responses that carry behaviorally meaningful information. For example, following auditory fear conditioning, the response of NE axons increased only for the conditioned stimulus; namely, the signal undergoes experience-dependent plasticity and is specific to meaningful sounds. Using simultaneous imaging of NE axons and local dendrites, we found dendritic responses to auditory stimuli in the barrel cortex and that the probability of these responses increased nonlinearly with NE axons Ca2+ signal amplitude. Our results demonstrate that the activity of the noradrenergic neurons may have a key role in binding multi-modal information through dendritic modulation