How sleeping neonates smile

Infants over one month of age tend to produce two types of smiling during especially positive social interactions, Duchenne smiles involving cheek raising and open‐mouth smiles. Little is known, however, about the prevalence, frequency, duration and organization of these smiles among neonates. Twenty‐five full‐term, healthy neonates (12 female) were videotaped during six minutes of sleep. Smiles were identified and analysed using an anatomically based coding system (FACS/Baby FACS). One‐half of the neonates showed bilateral Duchenne smiles. One‐quarter of the neonates showed bilateral Duchenne smiles at a mature level of intensity whose median duration was 1? s. By contrast, open‐mouth bilateral smiles occurred in less than one‐tenth of the sample. The contrast between the more frequent bilateral Duchenne smiles and the less frequent open‐mouth smile is discussed in terms of the early synergistic functioning of facial muscles and contrasted with the smiling patterns of older infants.     

Communication and crying in newborns

Few studies have analysed newborns’ crying behaviour in relation to the communicative context. In the present study, duration, latency and dysphony of newborns’ cry were analysed in three different communicative conditions: absent, continuous and discontinuous tactile communication. Thirty newborns were randomly assigned to three tactile communicative procedures. Subsequently they were presented with two visual stimuli, face (social-stimulus) and square (non-social-stimulus). The study showed that newborns cried only during visual stimuli presentation both in absent and continuous communication conditions. Newborns with absent communication cried more, with shorter latency and more dysphony than newborns with continuous communication. No significant differences were found in duration, latency and dysphony of newborns’ cry between the two stimuli. Newborns in the discontinuous communicative condition did not cry either during tactile communication or during visual stimuli presentation. Different communicative contexts affected the newborns’ crying behaviour during stimuli presentation. Different interpretations are discussed here in order to explain the results.     

Spontaneous facial expressions of happy bowlers and soccer fans

Kraut and Johnston (1979) found surprisingly few smiles in large samples of bowlers and hockey fans during happy events--unless they were simultaneously engaged in social interaction. A limitation of their studies is that there was no direct test of subjects' actual emotional experience at the moments in which they were observed. This article reports two field studies in which emotions were reported by bowlers and by soccer fans. Analysing facial behaviour of those who reported happiness, we found a low probability of smiling in the absence of social interaction (.09 for bowlers and .07 for soccer fans) and a high probability of smiling during social interaction (.78 and .70). These findings question the common assumption that smiles are an indicator of happiness per se, and support the alternative hypothesis of a more complex and indirect relationship between smiling and happiness.     

What's in a smile?

In positive social contexts, both adults and older infants show more Duchenne smiling (which involves high cheek raising) than non-Duchenne smiling (which does not). This study compared Duchenne and non-Duchenne smiles in early infancy for clues to their emotional significance. Infants (N = 13) from 1 to 6 months of age were videotaped weekly for 5 min in 208 face-to-face interactions with their mothers. Levels of Duchenne and non-Duchenne smiling were correlated within interactive sessions, and the 2 smiles had similar developmental trajectories. Duchenne smiles were typically preceded by non-Duchenne smiles. The results suggest these frequently contrasted types of smiles occur in similar situations and are often different temporal phases of a continuous emotional process. In contrast to adults, infant Duchenne smiles had longer durations than non-Duchenne smiles, suggesting infant smiling does not fit adult models of emotional functioning.     

VOLUNTARY SMILING CHANGES REGIONAL BRAIN ACTIVITY

Abstract— We used measures of regional brain electrical activity to show that not all smiles are the same. Only one form of smiling produced the physiological pattern associated with enjoyment. Our finding helps to explain why investigators who treated all smiles as the same found smiles to be ubiquitous, occurring when people are unhappy as well as happy. Also, our finding that voluntarily making two different kinds of smiles generated the same two patterns of regional brain activity as was found when these smiles occur involuntarily suggests that it is possible to generate deliberately some of the physiological change which occurs during spontaneous positive affect.     

The inappropriate smile and zygomatic muscle activity

Long-term recording of activity of the zygomatic muscle, the most important mimic muscle involved in smiling, was performed in 22 disorganized type schizophrenic patients with inappropriate smiles and 15 normal subjects in two separate experiments. During inappropriate smiles, the zygomatic muscle exhibited waxing and waning bursts of activity with an amplitude of 75 to 120 microV, which could not be distinguished from the activity observed during usual smiling in normal subjects. However, the duration of such activity tended to be longer when compared to that in usual smiling by normal subjects as well as by schizophrenic patients. In contrast to usual smiles, inappropriate smiles decreased with personal contact. When asked about their thoughts during smiling shortly after inappropriate smiles, more patients reported that they thought of nothing at all or something not necessarily pleasant rather than something pleasant that would be expected to induce smiling.     

Infants' responses to mothers' imitative behaviors

Several investigators have suggested that young infants' smiles and vocalizations following their mothers' imitative behaviors might reflect infant recognition that the mother's behavior is imitative or at least contingent. This study investigated whether infants smile and vocalize more frequently subsequent to maternal imitative than non-imitative behavior during both spontaneous and imitative face-to-face interactions. Fourteen 3 1/2-month-old infants and their mothers were videotaped in these two face-to-face interaction situations. The infants vocalized more frequently during the imitative situation and infant vocalizations plus simultaneous smiling, and vocalizations occurred more often following maternal imitative than non-imitative behavior. Although these data suggest that infant vocalizations and simultaneous smiles and vocalizations may reflect the infants' recognition of maternal imitative behavior, they do not establish definitively that it is the imitation per se vs. the contingency aspect that is recognized by the infant.     

Smiling in the face of adversity: the interpersonal and intrapersonal functions of smiling

This study examined hypothesized interpersonal and intrapersonal functions of smiling in positive and negative affective contexts. Smiles were measured during a lab-based monologue task following either happy or sad emotion-evoking films. Psychological adjustment and social integration were measured longitudinally using data obtained in years prior to and after the experimental task. Duchenne (genuine) smiles predicted better long-term adjustment and this effect was mediated independently by both social integration and undoing of negative emotion during the monologue. These effects were observed only in the negative affective context. Non-Duchenne smiles were not related to psychological adjustment. Neither Duchenne nor non-Duchenne smiles during the monologue task were related to personality variables assessed in this study.     

Sleep Architecture in Infants of Substance‐Abusing Mothers

This longitudinal, year‐long study compared sleep–wake state organization in two groups of infants–infants whose mothers abused substances during their pregnancies and nonexposed, typically developing, age‐matched comparison infants–to determine whether differences in sleep–wake state organization existed between the two groups. Seventeen infants of mothers who were participating in a parent–infant residential treatment program for substance abuse were enrolled. Their sleep–wake state organization over the first year of life was compared to that of 17 age‐matched comparison infants. The intent was to follow each infant on five occasions over the first year of life using established methods of time‐lapse videosomnography to record sleep–wake state organization; however, attrition in the substance‐abusing group was problematic. Some sleep–wake variables (i.e., Active Sleep%, Quiet Sleep%, Awake%, number of nighttime awakenings) were similar for both groups of infants at comparable ages across the first year. Total sleep time and the longest sustained sleep period (sleep continuity variables) differed significantly at some of the ages measured. Although overall sleep architecture appears highly resilient and well organized, some indications of sleep fragmentation and shortened nighttime sleep periods were observed in the substance‐exposed infants. More research is needed to explain why sleep‐continuity variables and not sleep‐state proportion variables differed between the two groups.     

Active sleep is associated with the face preference in the newborns who familiarized with a responsive face

Aim of this study was to investigate the preferential looking behaviour, subsequent to a familiarization task (8-min) with a previously responsive or motionless face, before and after a sleep cycle. Moreover, the role of the active sleep in memory consolidation of the responsive or motionless faces was explored. Hypotheses were that the newborns undergoing a motionless familiarization will exhibit a novelty effect (preference for the novel face) whereas the newborns undergoing a responsive familiarization will show a familiarity effect (preference for the known face) before and after the sleep cycle; moreover, the amount of active sleep will be associated with the looking time at the known face after a sleep cycle.Forty-five healthy full-term newborns were randomly assigned to two groups (group 1: motionless-familiarization and group 2: responsive-familiarization); in both groups newborns were video-recorded during four post-familiarization face-preference tasks, two of them performed before and two after a sleep cycle.During the pre-sleep-trials, there was not a significant preference for one face in both groups. During the post-sleep trials, the newborns showed a clear preference for the novel face. This effect was more evident in group 1. Only in group 2 there was a significant positive correlation between the active sleep duration and the looking duration at the known-face during the post-sleep trials (r = 0.41; p = 0.040). Multiple regression confirmed that only in the group 2 the total duration of the active sleep was associated with the looking duration at the known-face during the post-sleep trials (Adjusted R² = 0.13; β = 0.41; t = 2.2; p = 0.040).Findings showed that in newborns the face representation can be recalled after a sleep cycle. Moreover, the amount of the active sleep predicted the post-sleep looking toward the known-face only in the newborns who interactively familiarized with the face.     

Facial expressions,smile types,and self-report during humour,tickle, and pain

The nature of ticklish smiling and the possible emotional state that accompanies it have been pondered since the ancient Greeks. The present study is arguably the first to systematically examine facial behaviour and self-reports of emotion in response to tickling. Using a within-participants design, 84 participants' responses to being tickled were compared to their responses when experiencing a painful stimulus and their responses to comedy. Overall results for both self-report and facial action coding showed that the tickle condition elicited both pleasure and displeasure. Facial action during tickling included “Duchenne” smiles plus movements associated with negative emotions. Results suggest that tickle-induced smiling can be dissociated from positive affect. Accounts of tickle are discussed.     

The value of genuine and polite smiles

Humans show remarkable ability to adapt their social behavior to suit the changing requirements of their interactions. An interaction partner's social cues, particularly facial expressions, likely play an important role in motivating and reinforcing this behavioral adaptation. Over three studies, we test a key aspect of this idea. Specifically, we ask how the reinforcement value of facial expressions compares to that of nonsocial feedback and to what degree two frequently occurring expressions (genuine and polite smiles) differ in reinforcement value. Our findings show that social feedback is preferred over nonsocial feedback and that genuine smiles are preferred over polite smiles. Based on a logistic model of our data, we show that both monetary and social values of stimuli contribute significantly to participants' decisions. Indeed, participants were willing to sacrifice the chance of a monetary reward to receive a genuine smile and produced inflated estimates of the value of genuinely smiling faces. These findings suggest that genuine smiles, and potentially other social cues, may be useful social reinforcers and therefore important in the control of social behavior on a moment-to-moment basis during interaction.     

Coyness in Early Infancy

The present exploratory study reports the presence of ‘coy’ smiles beginning at 2‐3 months in infancy, consisting of smiling with simultaneous gaze and head aversion and curving arm movements. Five infants were video‐taped in natural interaction in their homes once a week between 7 and 20 weeks of age. These smiles were elicited in contexts of social attention, and were more likely following the renewed onset of attention. They occurred in interaction with familiar adults, with strangers and with the self in a mirror. Such expressions have previously only been reported in adults and in toddlers in the second year and have been interpreted as self‐conscious emotional reactions deriving from newly developing self‐conscious cognitions. The morphological and functional similarities between these early expressions and those reported in toddlers and adults suggest a developmental continuity in these reactions.     

Automaticity of the interpersonal attitude effect on facial mimicry: It takes effort to smile at neutral others but not those we like

People often mimic others more if the other is liked, a member of an ingroup, or in a cooperative relationship with the observer; we call this the interpersonal attitude effect. This study examines the degree to which this attitude effect on mimicry is an automatic or an effortful process. While under cognitive load or no load, participants observed positive, negative, and neutral others making emotional expressions. Electromyography measured corrugator supercilii (knits brow) and zygomaticus major (raises corners of mouth) activity. Under load, participants mimicked smiles of positive individuals but not neutral or negative individuals. During no-load trials, participants did not mimic negative individuals, but did mimic smiles of neutral and positive individuals. Participants enhanced their smiles in response to the smiles of liked others without effort, but smiling at neutral others’ smiles required greater cognitive resources.     

Development of sleep/wake,activity and temperature rhythms in newborns maintained in a neonatal intensive care unit and the impact of feeding schedules

Biological rhythms in infants are described as evolving from an ultradian to a circadian pattern along the first months of life. Recently, the use of actigraphy and thermistors with memory has contributed to the understanding of temporal relations of different variables along development. The aim of this study was to describe and compare the development of the rhythmic pattern of wrist temperature, activity/rest cycle, sleep/wake and feeding behavior in term and preterm newborns maintained in a neonatal intensive care unit (NICU).MethodsNineteen healthy preterm and seven fullterm newborns had the following variables monitored continuously while they were in the NICU: activity recorded by actigraphy, wrist temperature recorded with a thermistor and observed sleep and feeding behavior recorded by the NICU staff with diaries. Subjects were divided in 3 groups according to their gestational age at birth and rhythmic parameters were compared.ResultsA dominant daily rhythm was observed for wrist temperature since the first two weeks of life and no age relation was demonstrated. Otherwise, a daily pattern in activity/rest cycle was observed for most preterm newborns since 35 weeks of postconceptional age and was more robust in term babies. Feeding and sleep/wake data showed an almost exclusive 3 h rhythm, probably related to a masking effect of feeding schedules.ConclusionsWe found that wrist temperature develops a daily pattern as soon as previously reported for rectal temperature, and with acrophase profile similar to adults. Moreover, we were able to find a daily rhythm in activity/rest cycle earlier than previously reported in literature. We also suggest that sleep/wake rhythm and feeding behavior follow independent developmental courses, being more suitable to masking effects.     

Maternal well-being and sleep–wake behaviors in infants: An intervention using maternal odor

The development of an organized sleep–wake cycle in young infants is influenced by characteristics of both the infant and the parent, and by the nature of their dyadic interaction. Sleep–wake state organization is influenced first by homeostatic biological regulation, and later by socioemotional regulation. This report describes a feasibility study using an olfactory intervention designed to bridge the transition from physiologic to social regulation in sleep–wake state organization. A sample of 21 mother–infant dyads participated in an one year longitudinal study, after random assignment to either an experimental condition with a maternal odor-laden sleepaid, representational sleepaid (RSA) or a control condition with a neutral sleepaid, Sham Control (SC). Self-report questionnaires measured maternal psychological well-being, and video taping recorded infant sleep–wake behaviors repeatedly throughout the first year. RSA mothers reported significantly better levels of well-being throughout the year. At six and twelve months, mothers who reported more depressive feelings exhibited different nighttime interaction patterns. Infant sleep–wake state organization and sleepaid use changed significantly during the first year but were not altered by the intervention. © 1997 Michigan Association for Infant Mental Health     

Smiles as signals of lower status in football players and fashion models: Evidence that smiles are associated with lower dominance and lower prestige

Across four studies, the current paper demonstrates that smiles are associated with lower social status. Moreover, the association between smiles and lower status appears in the psychology of observers and generalizes across two forms of status: prestige and dominance. In the first study, faces of fashion models representing less prestigious apparel brands were found to be more similar to a canonical smile display than the faces of models representing more prestigious apparel brands.?In a second study, after being experimentally primed with either high or low prestige fashion narratives, participants in the low prestige condition were more likely to perceive smiles in a series of photographs depicting smiling and non-smiling faces. A third study of football player photographs revealed that the faces of less dominant (smaller) football players were more similar to the canonical smile display than the faces of their physically larger counterparts. Using the same football player photographs, a fourth study found that smiling was a more reliable indicator of perceived status-relevant personality traits than perceptions of the football players' physical sizes inferred from the photographs.     

Effects of normal and perturbed social play on the duration and amplitude of different types of infant smiles

Different types of smiling varying in amplitude of lip corner retraction were investigated during 2 mother-infant games--peekaboo and tickle--at 6 and 12 months and during normally occurring and perturbed games. Using Facial Action Coding System (FACS), infant smiles were coded as simple (lip corner retraction only), Duchenne (simple plus cheek raising), play (simple plus jaw drop), and duplay (Duchenne plus jaw drop). In addition, again using FACS, the amplitude of lip corner retraction was coded on a 5-point scale. Rather than a single smile expression that differs only in amplitude, the authors found a complex family of different smile expressions differing in their duration and amplitude as a function of game, setup versus climax of the game, and perturbation. Both type of smiling and amplitude of smiling appear to be controlled independently by the infant in relation to the context. These findings reveal systematic and context-specific nuances in infant smiles in the 2nd half of the first year.     

Yawning frequency and distribution in preterm and near term infants assessed throughout 24-h recordings

Yawning has been observed in foetuses and preterm infants. The aim of this study was to assess the frequency and the 24 h distribution of yawning in preterm infants.Twelve low-risk infants between 31 and 40 weeks of post-conceptional age (PCA) were continuously video-recorded for 24 h in their incubator. Spontaneous yawning was defined as opening of the mouth to its full extension in a dramatic stretch movement.The results showed that the rate of yawning across the 24-h period was 1.10/h. The highest incidence of yawns was in the waking motility pattern when compared to active sleep or quiet sleep motility patterns.Between 31 and 40 weeks, yawn incidence significantly decreased mainly during the day. The marked decrease in yawn frequency with age may be related to the development of circadian and homeostatic control of sleep and wake.     

Sleep disruption and motor development: Does pulling-to-stand impacts sleep–wake regulation?

During the second half of the 1st year, periods of increased sleep disruption have been documented alongside overall improvement in sleep–wake regulation. The objective of the present research was to test if pulling-to-stand (PTS), a milestone typically achieved during the latter part of the 1st year, co-occurs with a period of disrupted sleep. In a longitudinal design, 20 healthy infants were followed-up, from 7 to 11–12 months, at 3-week intervals. Each measurement consisted of filmed motor observations and sleep recordings (actigraphy), both conducted at home. It was found that among early achievers of PTS (by 8 months), the milestone was time-linked to a period of disrupted sleep. The results point to the significance of timing in the interplay between domains of development, and highlight the importance of considering both chronological and developmental metrics in studying changes in sleep–wake regulation.