Schedule of Events | Symposia

Integrating Context and Time in Perceptual Decision-Making: Insights from Peripheral Focused Ultrasound Stimulation

Poster Session F - Tuesday, April 1, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Doga Dogan¹ (ddogan6@gatech.edu), Aya Rezeika², Audrey Leroux¹, Tansu Çelikel¹; ¹School of Psychology, Georgia Institute of Technology, ²Donders Institute for Brain, Cognition and Behavior, Radboud University

Perceptual decision-making is influenced by the interplay between stimulus predictability and temporal uncertainty, as well as global and local stimuli correlations. In this study, we investigated how these factors impact perceptual thresholds for tactile sensitivity using non-invasive focused ultrasound stimulation (FUS). Its high spatial resolution, non-contact nature of force delivery, and spatiotemporal control over sound wave parameters make it an ideal method for quantitatively studying the sense of touch. The study was conducted with human subjects (N = 82, age group: 18-37, all genders) who were instructed to respond if they felt a vibration on their fingertip under varying conditions, assessing the effects of stimulus predictability (priming), temporal uncertainty, and stimulus surprise. Our results show that contextual information (global correlations) and increasing the number of sensory channels (auditory cue) independently improve stimulus detection and reaction times. Temporal uncertainty, however, slows down decision-making and increases sensitivity thresholds independent from local or global correlations. During multi-sensory integration the detection probability is independent from whether stimuli are locally coherent, but reaction times are improved if stimuli are correlated across repetitions (i.e. global correlations). These results suggest that stimulus predictability modulates sensory and motor processes independently. Distributed surface EEG recordings across the two hemispheres revealed a parieto-frontal circuit encoding stimulus predictability in a context- and time-varying manner. These findings suggest that the brain integrates contextual cues and temporal information across sensory modalities through distinct neural circuits to optimize perceptual processes and motor responses.

Topic Area: PERCEPTION & ACTION: Multisensory