Slide 17
The Responsiveness of Pyramidal Cells Increases During the UP State
To investigate the mechanisms by which the UP state is started and stopped by the activation of afferents, we examined the response of cortical pyramidal cells (and interneurons) to the start and stop stimuli. Note that the start and stop stimuli are identical stimuli applied either locally in layer 5, or at the white matter/layer 6 border. The responsiveness of the pyramidal cell is enhanced by the UP state - although the cell never generates more than one action potential to the activated synaptic input.