The influence of auditory and visual information on the neuromuscular control of chewing crispy food

Abstract

The influence of auditory and/or visual information on the neuromuscular control of chewing a crispy food was investigated. Participants chewed biscuits of three different levels of crispness under four experimental conditions: no masking, auditory masking, visual masking, and auditory plus visual masking. The order of the four masking condition blocks was randomized. The sound of chewing was masked by loud sounds on a headphone, and visual masking of the food was achieved by closing the eyes. Mechanical tests were performed on the biscuits to determine their characteristics, yield force, and sound production. Skull vibration, jaw-muscle activity, and jaw movement were measured while the subjects chewed and swallowed the food. Auditory and/or visual masking did not have a significant effect on skull vibration, muscle activity, and number of chewing cycles until swallowing. However, auditory and/or visual masking significantly increased the chewing cycle duration, but only for the participants who started the experiments with auditory and/or visual masking. The other participants were not influenced by masking. The memory of the unmodified stimuli helped these subjects to maintain their habitual chewing rate in later trials.

How do visual, auditory and motor dual‐tasking each affect swallowing and chewing function?

“…[38][39][40] It is well known that auditory masking of food causes chewing time to be prolonged. 39,41 The mixing of the auditory stimulus and the chewing sound in auditory dual-task condition may have resulted in a longer chewing time.…”

“…Based on auditory information from the food during chewing, the structure of the food is perceived, and the chewing speed and chewing function are adjusted 38–40 . It is well known that auditory masking of food causes chewing time to be prolonged 39,41 . The mixing of the auditory stimulus and the chewing sound in auditory dual‐task condition may have resulted in a longer chewing time.…”

“…Median (IQR) total chewing time (sec) for baseline visual dualtask, auditory dual task and motor dual task was 37 (30-45), 38 (32)(33)(34)(35)(36)(37)(38)(39)(40)(41)(42)(43)(44)(45)(46)(47)(48), 46 (37-57) and 40.5 (32-43), respectively. There was a significant difference in total chewing time among the tasks (χ 2 (3) = 9.02, p = .02).…”