The impact of disgust learning on memory processes for neutral stimuli: a classical conditioning approach

Disgust is a basic emotion that promotes pathogen avoidance and can contaminate nearby neutral stimuli. This study investigates how neutral stimuli, which have acquired disgust value through classical conditioning, are processed in episodic memory. The Category Conditioning paradigm was utilised to assign emotional significance to neutral stimuli, followed by a recognition test conducted immediately or 24 h after conditioning (Experiment 1). The results revealed that neutral stimuli that acquired disgust value were recognised with greater accuracy and higher liberal bias compared to other neutral stimuli in the recognition test conducted after 24 h, but not immediately. Present study also indicates that the memory enhancement observed with disgust did not manifest in the context of fear (Experiment 2). Additionally, the results varied when neutral stimuli associated with disgust were presented with disgusting stimuli in recognition test (Experiment 3). Thus, the present study demonstrates that the memory advantage of disgust extends to associated stimuli when they are presented in a list without disgusting stimuli.