Figure 9.

Innocuous auditory conditioning of PBN responses. A, B, A PBN neuron that responds to noxious heat stimuli (A) does not respond to an innocuous tone before conditioning (B, black trace) but responds robustly to the tone after a conditioning (red). C, Representative traces showing the same PBN neuron undergoing extinction (black) and responses after a second conditioning paradigm (red). D, Similarly, pupil responses to the innocuous auditory stimulus appear only after the conditioning paradigm (blue). E, Recordings from the same neuron after extinction of the conditioned responses (black trace) and after reconditioning the auditory response (blue). Data represent averages and 95th confidence intervals, indicated by the horizontal dotted lines. F, Similarly, pupil responses to the innocuous auditory stimulus appear only after the conditioning paradigm (blue). G, Average pupil area after a conditioning paradigm for all 6 animals. H, Recordings from the same neuron after extinction of the conditioned responses (black trace) and after reconditioning the auditory response (blue). I, Average pupil area after the second conditioning paradigm for all 6 animals. Data represent averages and 95th confidence intervals, indicated by the horizontal dotted lines.