A method for the assessment of facial hedonic reactions in newborns

Brow and Masticatory Muscle Activity Senses Subjective Hedonic Experiences during Food Consumption

Sensing subjective hedonic or emotional experiences during eating using physiological activity is practically and theoretically important. A recent psychophysiological study has reported that facial electromyography (EMG) measured from the corrugator supercilii muscles was negatively associated with hedonic ratings, including liking, wanting, and valence, during the consumption of solid foods. However, the study protocol prevented participants from natural mastication (crushing of food between the teeth) during physiological data acquisition, which could hide associations between hedonic experiences and masticatory muscle activity during natural eating. We investigated this issue by assessing participants’ subjective ratings (liking, wanting, valence, and arousal) and recording physiological measures, including EMG of the corrugator supercilii, zygomatic major, masseter, and suprahyoid muscles while they consumed gel-type solid foods (water-based gellan gum jellies) of diverse flavors. Ratings of liking, wanting, and valence were negatively correlated with corrugator supercilii EMG and positively correlated with masseter and suprahyoid EMG. These findings imply that subjective hedonic experiences during food consumption can be sensed using EMG signals from the brow and masticatory muscles.

Analysis of facial expressions in response to basic taste stimuli using artificial intelligence to predict perceived hedonic ratings

Taste stimuli can induce a variety of physiological reactions depending on the quality and/or hedonics (overall pleasure) of tastants, for which objective methods have long been desired. In this study, we used artificial intelligence (AI) technology to analyze facial expressions with the aim of assessing its utility as an objective method for the evaluation of food and beverage hedonics compared with conventional subjective (perceived) evaluation methods. The face of each participant (10 females; age range, 21–22 years) was photographed using a smartphone camera a few seconds after drinking 10 different solutions containing five basic tastes with different hedonic tones. Each image was then uploaded to an AI application to achieve outcomes for eight emotions (surprise, happiness, fear, neutral, disgust, sadness, anger, and embarrassment), with scores ranging from 0 to 100. For perceived evaluations, each participant also rated the hedonics of each solution from –10 (extremely unpleasant) to +10 (extremely pleasant). Based on these, we then conducted a multiple linear regression analysis to obtain a formula to predict perceived hedonic ratings. The applicability of the formula was examined by combining the emotion scores with another 11 taste solutions obtained from another 12 participants of both genders (age range, 22–59 years). The predicted hedonic ratings showed good correlation and concordance with the perceived ratings. To our knowledge, this is the first study to demonstrate a model that enables the prediction of hedonic ratings based on emotional facial expressions to food and beverage stimuli.

Orofacial anthropometric measures in full-term newborns

PURPOSE

To describe and compare the anthropometric measurements and the orofacial proportions of healthy term newborns (NB) according to sex, from a public maternity hospital in the state of Sergipe, northeastern Brazil.

METHODS

Descriptive and analytical randomized study was carried out. The participants included were 46 randomly selected healthy and full-term RNs of both sexes. A digital caliper was used to measure measurements (in millimeters) with the NB supine and occluded lips. Twice different, previously trained researchers measured each NB. Data were described using simple and percentage frequencies. The mean differences were assessed using the Mann-Whitney test, with a significance of 5%. Associations evaluated by the Fisher Exact test, and Cohen D size effects were calculated.

RESULTS

Differences were found between the groups for the anthropometric measurements: midface third height (glabella-subnasal or sn-g) and bottom (subnasal-gnathion or sn-gn); and filter heights (upper-lip subnasal or sn-ls), the upper lips (subnasal-estomus or sn-sto), and lower (stomatal-gnathion or sto-gn), which was always greater in males. The orofacial proportions studied did not show differences between sexes.

CONCLUSION

The study showed the presence of sexual dimorphism for the measures of the face at birth in the population born in Aracaju, Sergipe.