Stress-Induced Impairment of a Working Memory Task: Role of Spiking Rate and Spiking History Predicted Discharge
Figure 2
Peri-stimulus time histograms (PSTHs) illustrate the effects of stress on plPFC neuron task-related spiking activity.
A) T-maze schematic and associated peri-event raster and histogram analysis illustrates prototypic (i) delay- (ii) run- (iii) branch- (iv) choice- (v) reward- and (vi) pickup-related activity observed from plPFC neurons (0 sec. = start of respective behavioral interval; n = 40 correct trials of a baseline recording session; Delay length = 20 sec.; 5 msec. bins). Colored fiduciaries indicate beginning of each major event of the T-maze task (Red, Start Box; Green, Gate; Magenta, Branch; Grey, Choice; Cyan, Reward; Yellow, Pickup). B) Task-related discharge of a single WS-type plPFC neuron during correctly executed trials with a left arm entry during the baseline recording session (17 trials; top) and subsequent stress session (11 trials; bottom). Delay-related spiking of this delay neuron was enhanced during stress. Inset illustrates recorded spike waveforms. PSTH y-axis represents spiking probability/bin normalizing for different numbers of trials (5 msec. bins). C) Run-related activity suppressed during stress conditions. D) Suppression of choice-related activity during stress. Labeling conventions of C–D are identical to B.