Neural and dendritic activity during sensory-based behaviour

Palmer LM

lorey Institute of Neuroscience and Mental Health, University of Melbourne.

In the living animal, sensory systems are generally not stimulated in isolation but are instead activated collectively. The task of understanding how neurons receive and transform this sensory input is central to explaining brain function during behaviour. Pyramidal neuron dendrites in the primary somatosensory cortex receive both feedforward input from the thalamus and feedback input from other cortical areas. Since the synaptic location of the different input streams are morphologically and functionally isolated, how sensory input is integrated and computed at the level a single neuron is currently unknown. Here I will present recent results investigating the activity of tuft dendrites of layer 2/3 pyramidal neurons in the primary somatosensory cortex during a sensory-based reward association task. We find that tuft dendrites alter their activity during the behavioural task when presented with multi-sensory input, increasing the occurrence of large Ca2+ events. This modulation of synaptic integration highlights the importance of feedback information in dendritic encoding of sensory-based behaviour.