Sarah Gardy¹ (), Laura Ahumada¹, Faith Gilbert¹, Hannah Engle¹, Christian Panitz², Andreas Keil¹; ¹University of Florida, ²University of Bremen

Aversive conditioning experiments repeatedly pair a neutral stimulus (CS+) with a stimulus (US, e.g., loud noise) that reliably elicits an unconditioned response. Other stimuli are not paired with an aversive stimulus. Eventually, the CS+ becomes predictive of the US, which is accompanied by visuocortical facilitation and heightened sensory gain when viewing the CS+. However, it is unclear whether this visuocortical response is specific to defensive/aversive association formation or reflects associative memory formation in general. To examine the possible impact of non-aversive associative learning on visual processing, a soft tone (65 dB) was paired with one of two possible high-contrast black-and-white circular gratings. Young adult (n=22) participants viewed four Gabor gratings with variations in orientation. Either a 15° or 75° grating was paired with the tone (counterbalanced across participants), while 35° or 55° orientations were never paired (generalization stimuli, GSs). The gratings were presented for 3000 ms and the soft tone was played only during the last 1000 ms of the CS+, co-terminating with the grating. Analyses were conducted on the first 2000ms of grating presentation (i.e., timespan before tone). A Morlet wavelet analysis was used to quantify activity in the alpha-band. Spectral estimates of the ssVEP amplitude were obtained. Results indicate that alpha power increases, rather than decreases, when expecting the tone (CS+). The ssVEP showed a small effect with the non-predictive cues prompting higher amplitude than the conditioned stimulus—the opposite of what has been found during aversive conditioning. Together these findings suggest that the visuo-cortical changes observed during aversive conditioning are specific to situations in which the US elicits a defensive response. Neutral US by contrast prompt responses similar to those observed in working memory, imagery, and anticipation tasks.