Pharmacological normalisation of gastric state reduces oculomotor avoidance of disgust
Channel: Edwin Dalmaijer
Date: 2021-10-04

Talk by Dr Edwin Dalmaijer at Reading Emotions 2021: Gut, Brain, and Affect (https://research.reading.ac.uk/cinn/reading-emotions-2021/). 

ABSTRACT 
Compared to our closest relatives, humans have a uniquely strong tendency to avoid potential contaminants. Even in preferential looking tasks, where participants can freely view pairs of one affective and one neutral image, they consistently avoid bodily effluvia. This effect remains after many consecutive repetitions, and while it can be temporarily reversed by rewarding participants for gazing at disgusting stimuli, that does not last when rewards are suspended. These and other findings show that disgust resists both habituation and cognitive reappraisal. One potential reason could be disgust's inherently visceral nature, which sets it apart from other emotions. Here, we directly tested this visceral hypothesis by employing an eye-tracking paradigm in a placebo-controlled randomised crossover design with the peripherally selective dopamine antagonist domperidone. This drug normalises gastric rhythm, but barely crosses the blood-brain barrier (and indeed had no effect in a control experiment sensitive to central dopaminergic manipulations). We found that oculomotor disgust avoidance was lower on domperidone compared to placebo, but only after reward-encouraged exposure. These findings suggest that the gastric changes induced by domperidone did not have an immediate effect, but required a period of recalibration during which participants' reduced gastric response in turn reduced their avoidance.

You can read more about the presented work in the following papers:



Dalmaijer, E.S., Lee, A., Leiter, R., Brown, Z., & Armstrong, T. (2021). Forever yuck: Oculomotor avoidance of disgusting stimuli resists habitiation. Journal of Experimental Psychology: General, advance online publication. doi: https://doi.org/10.1037/xge0001006


Nord*, C.L., Dalmaijer*, E.S., Armstrong, T., Baker, K., & Dalgleish, T. (2021). A causal role for gastric rhythm in human disgust avoidance. Current Biology, 31, p. 1-6. doi: https://doi.org/10.1016/j.cub.2020.10.087