Elliott M. Blass

On the road to obesity: Television viewing increases intake of high-density foods.

Television viewing (TVV) has been linked with obesity, possibly through increased sedentary behavior and/or through increased ingestion during TVV. The proposition that TVV causes increased feeding, however, has not been subjected to experimental verification until recently. Our objective was to determine if the amount eaten of two familiar, palatable, high-density foods (pizza and macaroni and cheese) was increased during a 30-min meal when watching TV. In a within-subjects design, one group of undergraduates (n = 10) ate pizza while watching a TV show of their choice for one session and when listening to a symphony during the other session. A second group of undergraduates (n = 10) ate macaroni and cheese (M&C). TVV increased caloric intake by 36% (one slice on average) for pizza and by 71% for M&C. Eating patterns also differed between conditions. Although the length of time to eat a slice of pizza remained stable between viewing conditions, the amount of time before starting another slice was shorter during TVV. In contrast, M&C was eaten at a faster rate and for a longer period of time during TVV. Thus, watching television increases the amount eaten of high-density, palatable, familiar foods and may constitute one vector contributing to the current obesity crisis.

Suckling- and sucrose-induced analgesia in human newborns

This experiment had three goals: 1. To identify the basis of sucking-induced analgesia in healthy, term, newborn humans undergoing the painful, routine, procedure of heel lance and blood collection. 2. To evaluate how taste-induced and sucking-induced analgesias combine to combat pain. 3. To determine whether facial grimacing was an accurate index of diminished pain, or whether it was linked to tissue trauma. We report that: 1. Sucking an unflavored pacifier was analgesic when and only when suck rate exceeded 30 sucks/min. 2. The combination of sucrose and nonnutritive sucking was remarkably analgesic; we saw no behavioral indication in nine of the ten infants that the heel lance had even occurred. 3. Grimacing was reduced to almost naught by procedures that essentially eliminated crying and markedly reduced heart rate during the blood harvesting procedure.

Sucrose attenuates a negative electroencephalographic response to an aversive stimulus for newborns

ABSTRACT. Reports that sweet taste calms crying in newborns and is analgesic against the pain caused by a heel lance served as the basis for this study. Electroencephalographic (EEG) activity, heart rate activity, and infants’ facial behaviors were recorded before and after a noninvasive, but noxious, heelstroke (procedure from the Brazelton Neonatal Behavior Assessment Scale). In a randomized and controlled trial, 34 newborns were administered 2 mL of water or sucrose solution before the heelstroke. Frontal EEG asymmetry scores were computed, and power in the 3 to 6 Hz frequency band was analyzed. Infants who received water showed increased relative right frontal EEG activation from baseline to the post-heelstroke phase, a pattern that typifies negative affect. The EEG of infants in the sucrose group did not change. Heart rate increased rapidly in both groups during the heelstroke phase. However, after the heelstroke, the heart rate of infants who received sucrose returned to baseline, whereas the heart rate of infants who tasted water remained elevated. During the heelstroke, the infants in the water group cried and grimaced twice as long as the infants in the sucrose group. These findings add to the growing literature showing that sucrose attenuates newborns’ negative response to aversive or noxious stimuli.

The Ontogeny of Face Recognition: Eye Contact and Sweet Taste Induce Face Preference in 9- and 12-Week-Old Human Infants.

Nine and 12-week-old infants (N = 140) who were either calm or crying sat facing a researcher for 3.5 min. The researcher gazed into the infants eyes with a smiling face or looked above the infants forehead. She delivered a 12% sucrose solution via a syringe or a pacifier, or she did not deliver anything. After the exposure period, the mother held her infant over her shoulder. Infant gaze direction was recorded while the infant faced the same researcher and a stranger. The confluence of sweet taste and eye contact was necessary and sufficient for calm 9- and 12-week-olds to form a preference for the researcher. Crying infants never did so, even though eye contact and sweet taste arrested crying. Different visual-gustatory combinations induced unanticipated affective states and are discussed within the contexts of cognitive mechanisms that mediate face learning and preference, the proximate mechanisms involved, and the evolutionary significance of face recognition.

Effects of colostrum in newborn humans: dissociation between analgesic and cardiac effects.

This study evaluates the effects of colostrum, delivered via syringe or on a pacifier, on the pain and heart rate reactions of newborns undergoing routine heel-lance. This was achieved by following a quasi-randomized, controlled trial in which 60 newborn infants at Boston Medical Center, Boston, MA, were randomly assigned to receive colostrum, sucrose, or water, by syringe or on a pacifier, for a total of 6 groups (n = 10 per group). The effectiveness of an intervention was determined by comparing crying, grimacing, and heart rate differences among groups during and following blood collection. We report that colostrum, delivered by syringe or on a pacifier, did not reduce crying or grimacing relative to control infants who received water. As has been previously reported, sucrose markedly reduced both crying and grimacing, and attenuated the rise in heart rate that normally accompanies blood collection (p < .002). Water, via syringe or on a pacifier, did not prevent the increase in heart rate, nor did colostrum via syringe. In contrast, colostrum delivered on a pacifier prevented the increase in heart rate despite pain reactivity and extreme crying. The implications of this dissociation are discussed.

Reduced heat loss following sucrose ingestion in premature and normal human newborns

To determine the energy savings caused by sucrose taste, we measured heat loss through direct calorimetry for 23 premature and normal term infants who were studied a total of 31 times. Following stabilization in the calorimeter, crying was induced by applying 1 ml cold water to the infants foot. After 4 min, 0.1 or 0.2 ml sucrose were delivered intraorally through a remote syringe to arrest crying. Crying was accompanied by a 13.2% increase in metabolic rate that was quickly and completely reversed during crying cessation caused by sucrose taste. Heat loss was inversely and linearly related to infant body weight. The implications of these findings for minimizing crying and energy expenditure in normal newborns and especially in ill or small newborns are discussed.

Infant Formula Quiets Crying Human Newborns

Milk (Similac), sucrose (12% wt/vol), or water were delivered to crying normal newborns once per minute for 5 minutes, in a volume of 0.1 mL/delivery. Milk and sucrose markedly reduced infant crying, and this calm persisted during the 3 minutes after substance delivery. Infants who received water were only marginally quieted, and this calm did not persist. Despite quieting agitated infants, milk did not cause them to bring their hands to their mouths during the period of milk treatment, whereas infants who received sucrose did bring their hands to their mouths. These data demonstrate that milk effectively quiets human newborns, that its quieting effects endure, and that the mechanisms that quiet and that underlie hand-in-mouth engagement are separable and independent.

Biological bases of face preference in 6-week-old infants

Six-week-old infants (N =40) who started the experiment in either a calm or crying state, received sucrose from an experimenter, while in eye contact with her. Sucrose was delivered either by syringe or on a pacifier. After 3.5 min., the experimenter retired, the mother came into the test room and placed her infant over her shoulder en face with a video camera. The experimenter and a confederate, both dressed identically, sat in front of and slightly to either side of the infant and the infant could choose to look at either experimenter. To minimize position bias, experimenters switched sides every 30 sec. To maintain a stable level of infant attention, they simultaneously called the babys name at 10 sec. intervals. When an infant looked at one or the other experimenters, she raised her thumb in camera view. Only crying infants who sucked a sweet pacifier showed a preference for their experimenter. As a group none of the other infants did so. However, there was a wide distribution of sucking times in calm week 6 infants. Choice was linearly related to sucking duration. Infants who sucked for substantial periods of time, showed a strong preference for the experimenter. Those who sucked for minimal periods of time strongly preferred the confederate. Based on these findings and ones from 9- and 12-week-old infants, a model is presented in which preference in this experimental paradigm is determined by idealized levels of central activation. These levels may be inferred from the normal crying function at a particular age.

Energy conservation in infants.

Energy acquisition through suckling has been widely studied in rat and human infants. Processes mediating energy conservation, however, have not received the attention that they deserve. This essay, in honor of Professor Jerry Hogan, discusses parallel behaviors used by rat and human mothers to minimize energy loss in their offspring. Parallel mechanisms underlying energy preservation have been identified in rats and humans, suggesting phylogenetic conservation and possibly continuity. This article is part of a Special Issue entitled: In Honor of Jerry Hogan.