Reduced Temporal Sensitivity in Obesity: Evidence From a Simultaneity Judgement Task.

Preliminary evidence showed a reduced temporal sensitivity (i.e., larger temporal binding window) to audiovisual asynchrony in obesity. Our aim was to extend this investigation to visuotactile stimuli, comparing individuals of healthy weight and with obesity in a simultaneity judgment task. We verified that individuals with obesity had a larger temporal binding window than healthy-weight individuals, meaning that they tend to integrate visuotactile stimuli over an extended range of stimulus onset asynchronies. We point out that our finding gives evidence in support of a more pervasive impairment of the temporal discrimination of co-occurrent stimuli, which might affect multisensory integration in obesity. We discuss our results referring to the possible role of atypical oscillatory neural activity and structural anomalies in affecting the perception of simultaneity between multisensory stimuli in obesity. Finally, we highlight the urgency of a deeper understanding of multisensory integration in obesity at least for two reasons. First, multisensory bodily illusions might be used to manipulate body dissatisfaction in obesity. Second, multisensory integration anomalies in obesity might lead to a dissimilar perception of food, encouraging overeating behaviours.