Bolus viscosity and spoon delivery geometry alter dynamic texture perception of a sweet potato model food and cortical beta oscillations during dual-task swallowing in healthy adults

Swallowing under dual-task conditions requires coordination between oral sensorimotor control and cognitive resource allocation, potentially altering cortical activity even in healthy individuals. This study examined the effects of spoon type and viscosity of pre-gelatinized purple sweet potato on beta-band oscillations during dual-task swallowing. Three viscosity levels (6%, 10.5%, and 18% w/w) were characterized by apparent viscosity and spreadability, while TPA was feasible only for the 18% formulation. Temporal Dominance of Sensations assessed dynamic texture perception. Cortical responses were recorded using electroencephalography, and beta-band event-related desynchronization/synchronization (ERD/ERS) was calculated during a concurrent working memory task. Increased viscosity significantly enhanced mechanical resistance and altered temporal perception. Both viscosity and spoon type significantly affected beta activity, while their interaction was not significant. Lower viscosity produced greater desynchronization, indicating higher sensorimotor demand. These findings demonstrate that food consistency and delivery geometry modulate cortical responses during cognitively demanding swallowing.