Behavioral Responses to Sucrose as an Indicator of Positive Hedonic Response Across the First Six Months of Infancy

Development of the Baby Behaviors when Satiated (BABES) Behavioral Coding Scheme

Current infant feeding recommendations promote responsive feeding, wherein caregivers respond to infants' cues to determine feeding pace and duration, to support infant self-regulation and healthier weight outcomes. A central tenet of responsive feeding is that infants will effectively signal hunger, receptiveness to feeding, needs to disengage from feeding, and satiation, yet there is a lack of research available to support this assumption. Rather, previous research illustrates substantial variability exists for the extent to which infants exhibit behavioral cues during feeding and that many mothers feel their infants do not clearly communicate satiation, suggesting certain caregivers need tailored support to understand their infants' needs during feeding interactions. As a first step toward addressing this research gap, we developed the Baby Behaviors when Satiated (BABES) coding scheme, a comprehensive tool that assesses infants' disengagement/satiation behaviors and mothers' responses to infant behaviors and feeding practices during mother-infant feeding interactions. The BABES was applied to 876 videos of bottle-feeding interactions from a prospective, longitudinal study of dyads observed when infants were 1, 2, 4, 6, 9, and 12 months old. Coders achieved moderate to strong inter-rater reliability and descriptive analyses illustrated that the percentages of infants and mothers exhibiting different behaviors at each age were consistent with developmental trends noted in previous research. Application of this tool within future research holds the potential to create rich datasets allowing for description of intra- and inter-individual variability in infant and mother behaviors and how infants' and mothers' behaviors co-develop across the first year.

Associations of maternal food addiction, dietary restraint, and pre-pregnancy BMI with infant eating behaviors and risk for overweight

Maternal food addiction, dietary restraint, and pre-pregnancy body mass index (BMI) are associated with high-risk eating behaviors and weight characteristics in children and adolescents. However, little is known about how these maternal factors are associated with individual differences in eating behaviors and risk for overweight in infancy. In a sample of 204 infant-mother dyads, maternal food addiction, dietary restraint and pre-pregnancy BMI were assessed using maternal self-report measures. Infant eating behaviors (as measured by maternal report), objectively measured hedonic response to sucrose, and anthropometry were measured at 4 months of age. Separate linear regression analyses were used to test for associations between maternal risk factors and infant eating behaviors and risk for overweight. Maternal food addiction was associated with increased risk for infant overweight based on World Health Organization criteria. Maternal dietary restraint was negatively associated with maternal report of infant appetite, but positively associated with objectively measured infant hedonic response to sucrose. Maternal pre-pregnancy BMI was positively associated with maternal report of infant appetite. Maternal food addiction, dietary restraint, and pre-pregnancy BMI are each associated with distinct eating behaviors and risk for overweight in early infancy. Additional research is needed to identify the mechanistic pathways driving these distinct associations between maternal factors and infant eating behaviors and risk for overweight. Further, it will be important to investigate whether these infant characteristics predict the development of future high-risk eating behaviors or excessive weight gain later in life.

A mechanistic staging model of reward processing alterations in individuals with binge-type eating disorders

Altered reward processing is thought to characterize binge-type eating disorders, but the exact nature of these alterations is unclear. A more fine-grained understanding of whether specific aspects of reward processing contribute to the development or maintenance of binge eating may point to new therapeutic targets and personalized treatments. The incentive sensitization theory of addiction proposes that repeated use of a substance increases the desire to approach a reward ('wanting') but not pleasure when consuming the reward ('liking'), suggesting that reward processes driving addiction change over time. We hypothesize that the same may be true for binge eating. Further, consistent with the maladaptive scaling hypothesis, reward processing may be heightened for multiple reinforcers in at-risk individuals but become tuned toward food once binge eating is initiated. In this article, we propose a mechanistic staging model of reward processing in binge-type eating disorders that synthesizes existing data and posits that alterations of reward processing depend on illness stage and reward type. We outline translational methods for testing key hypotheses and discuss clinical implications. Considering reward processing alterations in relation to illness stage has the potential to improve treatment outcomes by ensuring that the mechanisms targeted are personalized to the individual patient. PUBLIC SIGNIFICANCE: Individuals with binge-type eating disorders experience alterations in their desire for, and pleasure from, food. We believe that the exact nature of these alterations in reward processing change over the course of illness-from the at-risk state to an established illness. If true, treatments for binge-type eating disorders that target reward processing should be personalized to the illness stage of the patient.

Infant Distress in a Food Delay Task Changes With Development and Predicts Amount Consumed

Objective

Eating behavior regulation emerges during early development and involves general self-regulation (emotional, behavioral), appetite regulation (homeostatic metabolic need) and appetite self-regulation (including both Bottom-Up Food Approach and Bottom-Up Food Avoidance and top-down purposeful self-control of eating). Limited research has investigated developmental trajectories of the regulation of eating behavior before the preschool years. The current study used a novel food delay task to assess infant distress as an early emerging marker of eating behavior regulation constructs across early infancy and examine associations with amount of milk consumed.

Method

Mother-infant dyads (n = 179) completed the Ability to Delay Gratification for Food in Infants Task (ATDG-FIT) at 2 weeks, 8 weeks, and 16 weeks of age. The ATDG-FIT required infants to wait before being fed while their bottle was present, but not accessible (3-min Pre-Feeding Delay). After this, the infant was fed for 1 min, then the feeding was paused for 30 s (Mid-Feeding Delay). Infant distress was coded during each feeding delay period and the amount of milk consumed was measured.

Results

The mean proportion of distress during the Pre-Feeding Delay period decreased from 8 to 16 weeks of age (F(2,230) = 15.02, p < 0.001), whereas the mean proportion of distress during the Mid-Feeding Delay increased from 2 to 8 weeks of age (F(2,230) = 27.04, p < 0.001). There was a positive interaction between distress during Mid-Feeding Delay and infant age predicting the amount consumed in the protocol (ß = 0.30, p = 0.022), suggesting that the association between distress during this part of the task and amount consumed strengthens as infants get older.

Conclusion

The ATDG-FIT may be an effective method to assess emerging eating behavior regulation constructs during early infancy.

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.