Abstract
Evaluative conditioning typically involves a neutral perceptual stimulus and one that can trigger an emotional response. During conditioning the emotional response becomes associated with a previously neutral stimulus, so that the once neutral stimulus will now trigger an emotional response in isolation. There is strong evidence that mental imagery can involve perceptual mechanisms in early visual cortex. We hypothesized that if visual imagery does involve the same mechanisms as visual perception then we should be able to condition mental images in a manner similar to perceptual stimuli. During the conditioning phase of the experiment participants were instructed to imagine one of two oriented and colored gratings, after which a positive or negative emotional photograph was displayed (counter-balanced). During the test phase participants made judgements on the emotional content of a different set of pictures in a choice reaction time task. Shortly before each photograph was displayed one of the two previously imagined oriented gratings were briefly presented perceptually. We found that reaction times were faster when the emotional content in the photo matched the conditioned emotion of the oriented pattern during the imagery-conditioning phase (congruent pairing) and slower when it did not match (incongruent pairing). In addition, when the orientation of the perceptual test patterns was manipulated independently to color the RTs changed in a predictable manner consistent with known characteristics of early visual cortex. These data suggest that the previously neutral imagery patterns had taken on emotional value and this carried over to the perceptual stimuli (generalization).
UNSW, University International Postgraduate Award.