Visual and Auditory Stimuli Associated with Swallowing: An fMRI Study

Abstract

We focused on brain areas activated by audiovisual stimuli related to swallowing motions. In this study, three kinds of stimuli related to human swallowing movement (auditory stimuli alone, visual stimuli alone, or audiovisual stimuli) were presented to the subjects, and activated brain areas were measured using fMRI and analyzed. When auditory stimuli alone were presented, the supplementary motor area was activated. When visual stimuli alone were presented, the premotor and primary motor areas of the left and right hemispheres and prefrontal area of the left hemisphere were activated. When audiovisual stimuli were presented, the prefrontal and premotor areas of the left and right hemispheres were activated. Activation of Broca's area, which would have been characteristic of mirror neuron system activation on presentation of motion images, was not observed; however, activation of brain areas related to swallowing motion programming and performance was verified for auditory, visual and audiovisual stimuli related to swallowing motion. These results suggest that audiovisual stimuli related to swallowing motion could be applied to the treatment of patients with dysphagia.

Ressonância magnética funcional e deglutição: revisão sistemática

“…Concerning the auditory stimulus, answers in the supplementary area were observed and for the audiovisual stimulus, the pre-motor areas and prefrontal right and left hemisphere showed positive responses. It is concluded that the brain areas related to swallowing performance and programming were triggered by visual, auditory and audiovisual stimuli provided (16) . Studies showed no correlation concerning the lateralization aspects of the swallowing function in the cerebral cortex.…”

“…Scientific articles were categorized specific features to the swallowing cortical representation (3,(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23)(24)(25) . Research on elderly and patients with dysphagia underwent compared to control groups.…”

“…A chronological analysis of the presented studies, observed that initially the concern was the confirmation of cortical activation mechanisms for swallowing Therefore, procedures such as saliva (1,3,5,7,(16)(17)(18)(19)(20)22,23,26,(29)(30)(31)(32) , water (5,11,12,17,(24)(25)(26)28,29,31) , barium (5,26,29,31) swallowing were performed, comparing swallow and not swallow (1,7,14,27) . Later on, studies began to analyze differences in the cortical areas, responsible for each motor phase, differentiating the role of the structures involved.…”

“…Guidance provided to different groups of surveyed subjects included visual (3,7,8,10,14,(16)(17)(18)(19)(23)(24)(25)(26)(27)(28)(30)(31)(32) , hearing (6,16,21,29) and sensorial clues (5,9,11,13,15,17,19,24,29) . In studies examining the food swallowing, its ingestion was the track for the patient to swallow, i.e., the absence of formal statement was a major factor, differentiating it from studies with other types of tasks.…”

Swallowing Disorders in Clinical Practice: Functional Anatomy, Assessment and Rehabilitation Strategies

“…Swallowong movements are internal and not visible; biofeedback is used to increase swallowing biomechanic circuit. Studies use auditory feedback (hearing swallowing sounds), visual feedback (watching own laryngeal movements and normal movements), during swallowing exercises (18). Biofeedback is also combined with novel swallowing treatment maneuvers such as effortful swallowing or Mendelsohn maneuver (23).…”