Perception of elderly people with swallowing disorders on food served in hospital: an exploratory study using eye tracker and emotional face reader methodology to identify challenges and opportunities

Background: Individuals afflicted with dysphagia must modify the consistency of their diet, as there is no other viable option. The patient's acceptance of the diet may not have been given enough attention. This study examined the use of an implicit method to ascertain the perceptions of consumers with dysphagia regarding diets that vary in consistency (pureed or minced and moist) and adaptation (adapted for enhanced sensory experience or base diet).

Methods: A total of 14 participants diagnosed with dysphagia (n = 14) were presented with eight slides of hospital food trays and were asked to indicate whether they liked the food on display by responding “yes” or “no.” Participants’ gaze behavior was recorded using an eye-tracking technique. Subsequently, the participants viewed 16 individual dishes, indicating their level of liking, intention to consume food, and whether they believed it to be safe (answering yes or no). The participants' facial expressions were recorded throughout the experiment and the researchers assessed six discrete emotions.

Results: Regarding gaze behavior, the results indicated that the number of fixations, time to first fixation, and duration of first fixation were higher when participants responded in the negative than when they responded affirmatively to the question regarding their liking of the full tray. This discrepancy is likely because of the difficulty in recognizing food items. Pupil size was the primary factor influencing liking response when a classification tree was used. Regarding facial emotions, negative emotions associated with the adapted presentation of dishes were less prevalent than those observed in the base versions.

Conclusions: This study represents a preliminary investigation into implicit methods with participants with dysphagia in a hospital setting, aiming to elucidate the relationship between food liking and unconscious food liking.