Supplementary Figure 1: Recording sites and example waveform clustering, as well as electrophysiological recordings of auditory CS and shock processing following overtraining.
From: Modular organization of the brainstem noradrenaline system coordinates opposing learning states
(a) Recording sites in LC for experiments in which cells were held throughout fear conditioning and extinction. (b) Example waveforms and clusters from stereotrode recordings during pre-conditioning, fear learning and extinction experiments. (c) Experimental protocol. In overtraining experiments, all units (24 units) were optogenetically identified before CS, US, and CS-US presentations. (d,e) Perievent time histograms showing auditory CS (d) and shock US (e) evoked firing rate (y-axis) responses in example LC cells. Time is on x-axis with 0=CS or US onset time (CS period denoted by gray bar and US period denoted by orange bar). Bin size=500 ms (d), 200 ms (e). (f) Pie chart showing proportion of cells (n=24) auditory responsive (red, 45.8%), shock responsive cells (yellow inside, 79.2%) and those not exhibiting shock or auditory responding (black). 37.5% of cells responded to both CS and US, 8.3% responded to CS alone and 41.7% responded to US alone. (g) Heat plots showing auditory- (left) and shock-evoked (right) responses in all cells recorded aligned vertically by cell number. X-axis=time, 0 denotes tone CS or shock US onset, top gray bar shows tone CS duration and red bar shows US duration. Bin size=500 ms (left), 200 ms (right).
