DIFFERENT TYPES OF SMILES AND LAUGHTER IN ... Reports, 2001,89,547-558. O lJsychological Reports 2001 DIFFERENT TYPES OF SMILES AND LAUGHTER IN PRESCHOOL CHILDREN ' SIMONE SARRA AND

Psychological Reports, 2001,89,547-558. O lJsychological Reports 2001

DIFFERENT TYPES O F SMILES AND LAUGHTER IN PRESCHOOL CHILDREN '

SIMONE SARRA AND EMMA OTTA

Department of Experimenfal Psychology Univer.rity of580 Pa'aulo, Brazil

Szrmmay.-The relationship among m o r p h ~ l o ~ ~ c ~ ~ dkferent forms of smiling and laughter was examined. The participants were 19 B r ~ z d ~ a n preschool children. Each child was observed a total of 60 min. in three 10-rnln. sessions on the playground and three 10-min. sessions in che classroom. Analysis suggests thar the various forms of smiling do nor simply express different intensiries of a single emotion. A two-dimensional structure was indicated by factorial analysis. The f i s t dimension, which could be called plafiulness-mock aggression, consisted of a broad smile and laughter. The second dimension, which could be c d e d friendliness-appeasement, consisted of a closed and upper smile. The pattern of correlation found benveen expressive behaviors and both teacher's and peers' evaluations gives further support to the interpretation that s m h g is an heterogeneous category.

The human smile is one of the simplest and more easily recognized facial &splays. Only one muscle-the zygomatic major-controls the upward and outward movement of the nlouth corners, whereas the facial expressions of fear, sadness, and anger involve two to four different n~uscles. S m h g is -

more easily recognized at great distances or in short time periods in comparison with other signals of facial affect (Hager & Ekman, 1979; Ekman & Friesen , 1982).

The underlying control mechanisms for srnhng are far from being sim- ple. A number of issues related to the determinants and functions of this facial display s d remain controversial (Soussignan & Schaal, 1996; Dickson, Walker, & Fogel, 1997). Darwin (1872/1965) interpreted s m h g and laughter as an expression of mere joy or happiness, i.e., as the outward expressive components of internal emotional experiences, providing veridical informa- tion about the sender's internal state and promoting social interaction. He considered srnllmg as a diminutive form of laughter, differing from it only in intensity. Other authors claimed that smiling is a communicative behavior designed to maintain affiliation and may not reflect an underlying emotional state (Kraut &Johnston, 1979). Facial expressions are conceived of as social interaccive signals (Fridlund, 1991 ).

'This research was conducted with the support of Conselho Nacional de Desenvolvimento Cientifico e Tecnolbgico (Processo 306385-88) and CAPES. We thank Vera Silvia Raad Bussab and Fernando Leite Ribeiro for their comments on this study. Please address correspondence to Emma Otta, Ph.D., Departamento de Psicologia Experimental, Institi~to de Psicologia, Uni- versidade de Sno Paulo, Av. Prof. Mello Moraes, 1721, CEP 05508-900, Sso Paulo, Urasil or e- mail ([email protected]).

548 S. SARRA & E. OTTA

In contrast with many investigators who have not distinguished different topographical forms of smiling (Feldman & Ingham, 1975; Foot, Chap- man, & Smith, 1977; Lau, 1982; Reis, Wilson, Monestere, Bernstein, Clark, Seidl, Franco, Gioioso, Freeman, & Radoane, 1990), Brannigan and Hum- phries (1972) categorized this expressive behavior according to the extent and form of mouth opening and exposure of teeth: the closed smile in which the mouth corners are drawn up and out while the teeth remain covered, the upper smile in which the mouth corners are drawn up and out, and the upper lip is raised showing part of the upper teeth while the lower teeth remain covered, and the broad smile in which both the upper and lower teeth are exposed. These categories were named, respectively, basic, Du- chenne, and duplay smiles by Dickson, et al. (1997) and can be considered macrofacial measurement techniques. Another more fine grained facial measurement technique was developed by Ekman and Friesen (1982), the Facial Action Coding System (FACS). Using the system, Ekman and Friesen (1982), Frank and Ekman (1993), and Frank, Ekman, and Friesen (1993) ddferenti- ated an enjoyment smile from other types of smiles that are not associated with positive emotion by presence of orbicularis oculi action in conjunction with the zygomatic major (Duchenne smile), symmetrical action of the zygomatic major on both sides of the face, and smoother zygomatic major actions of Inore consistent duration.

Soussignan and Schaal (1996) investigated forms of s m h g associated with pleasant and unpleasant sensory experience, using the categories of Brannigan and Humphries (1972). Preschool and school-age children, from 4 to 15 years old, thought that they were participating in an assessment of their smell ab~lities. A bottle containing odorant stirnth was squeezed when the participant put the nose above an orifice and the facial responses were videotaped. There were four types of odorant stimuli: fruity, floral, fishy, and faecal. A significantly higher percentage of children displayed closed smiles in the unpleasant than in the pleasant olfactory condition.

Naturalistic studies show that ddferent types of smiles tend to occur in different contexts. Ten-mo.-old infancs react to the approach of a stranger with a closed smile, but to the approach of their mother with an upper smile (Fox & Davidson, 1988). Infants and preschoolers display closed smiles more frequently in nonsocial contexts, e.g., while playing alone with their toys, but open-mouthed smiles during social exchanges (Blurton Jones, 1972; Cheyne, 1976; Jones & Raag, 1989; Jones, Raag, & C o b s , 1990).

Van Hooff (1972) put forward the hypothesis that s m h g and laughter could be conceived as displays of ddferent phylogenetic origins that have converged to a considerable extent in the human species. The monkeys' and apes' silent bare-teeth display, a grimace in which the lips are drawn back and both sets of teeth are exposed, resembles in form and context a human

PRESCHOOL CHILDREN'S SMLLING. LAUGHTER 549

smile. The grunace functions as an appeasement gesture, which attenuates the hosule behavior of dominant animals. It is also displayed when an animal is trying to reassure a less dominant one, as when a male approaches a mother with her infant. It seems to function also as a sign of attachment. The re- laxed open-mouth display, characterized by a widely opened mouth and lips that remain covering the greater part of the teeth, is considered a possible homologue of human laughter. The display is often accompanied by quick and shallow rather staccato breathing that in some species, e.g., the chimpanzee, may be vocalized, sounding b e 'ahh ahh ahh'. It is easily elicited by tickling (Foley, 1935). It also accompanies rough-and-tumble play and may function as a metacommunicative signal that the ongoing behavior is not aggressive (Bateson, 1955).

We conducted the present study to address a series of issues. First, we examined the relationship among morphologically different smiles and laughter in Brazhan preschoolers, guided by the controversy of whether the various forms of s m h g are simply lower-level variants of laughter or represent different categories? The few available studles with preschoolers focused on various forms of s m h g were done more than 20 years ago and did not in- clude laughter (Blurton Jones, 1972; Cheyne, 1976). One study (Bainurn, Lounsbury, & Poho, 1984) examined simultaneously smiling and laughter but lumped together different types of smiles, leadmg their authors to state that "the issue of whether to consider laughing and s m h g as different lev- els of the same response or as separate responses is a ddficult one to de- cide" (p. 1955). We analyzed the structure of interrelations among three types of smiles and laughter through factor analysis with the purpose to de- fine the underlying structure (Hair, Anderson, Tatham, & Black, 1995).

Second, we examined the hypothesis that sex influences rates of s m h g and laughter. American researchers consistently reported that women smile more than men do in a wide variety of social contexts: when greeted (Mack- ey, 1976), during a conversation (Halberstadt, Hayes, & Pke , 19881, or pos- ing for a photograph (Morse, 1982; Ragan, 1982; W s , 1984; Otta, 1998). In therapeutic groups, Pollio and Edgerly (1976) observed that females smiled and laughed more than males, although they joked less. Analyzing poses for ~ h o t o ~ r a p h s , Berman and Smith (1984) found that Canadian pre- adolescent girls smiled significantly more often than boys did, whereas Otta (1998) found no sex difference in smiling among Brazilian preschoolers. Babad, Alexander, and Babad (1983) also found no difference between both American and Israeli boys and girls in the rate of returning smiles of a stranger.

Finally, we sought to investigate the relationship of s m h g to teachers' judgements of social competence, happiness, and leadership, and to peers' acceptance. Alexander and Babad (1981) and Babad, et al. (1983) found that

550 S. SAKKA & E. OTTA

from preschool to junior high school American children were more likely than Israeli children to return the smile of a friendly stranger with a smile. In both countries teachers were aware of individual differences in the nonverbal expressive style of their students. They successfully identified smilers and nonsmilers beyond chance and judged smilers as more socially competent in preschool and junior high school. Whereas American teachers con- tinued to judge smilers as more socially competent in the elementary grades, Israeli teachers judged smilers as less socially competent. The researchers sug- gested that their results reflected cultural dfferences in sociahzation goals. The major goal of Israeli sociahzation is to produce competent and indepen- dent adults as soon as possible, since the defense of the country depends heavily on the performance of the young. To accomplish this goal, the social- izing agents reduce the spontaneous expression of positive affect as the children grew older.

In our study with Brazhan preschoolers we also expected that the teacher would be aware of the general propensity of each child to smile, but in a different manner from Alexander and Babad (1981) and Babad, et al. (1983) we have classified different types of smiles. The point is, would the teacher be aware of specific smiling propensities of the children? Would the teacher judge closed smilers more socially competent than nonclosed smilers?

Participants

Participants were 19 Brazilian children, 8 boys and 11 girls (M=4:3, range = 3 : 8 to 4 : 8), who attended a lndergarten in a private school in Slo Paulo. All children were Caucasian and from upper-middle-class homes.

Procedure

Observations were made by the first author (S.S.) during the second term of the year, so that the relationships among the children were already well established. Children were always observed in the middle of the week in similar contexts and activities. They were not observed on the first or last days of the week because, generally, children tend to feel more excited or tired on those days. Actual behavioral observations began after a period of three weeks of training, so famharity with the procedure and with the children could be gained.

Observations were made once a week on the playground, during free play, and inside the classroom during structured activities such as music and art. Each child was observed a total of 1 hr. (three 10-rnin. sessions in the classroom and three 10-min. sessions on the playground). The children were randomly assigned to the sessions.

PRESCHOOL CHILDREN'S SMILING. LAUGHTER 55 1

The specific coding categories used in this study were classified according to Brannigan and Humphries (1972): closed smile, upper smile, and broad smile. Cheyne (1976), Otta and Sarra (1990), Otta, Lira, Delevati, Ce- sar, and Pires (1994), Otta, Arnbrosio, and Hoshino (19961, Ragan (19821, and Soussignan and Schaal (1996) have used the same system of classifica- tion. Besides the three types of smiles, the category laughter was also in- cluded. Laughter was defined as inarticulate sounds of the form "ha-ha-ha." The record of the four categories was mutually exclusive.

Facial conhgurations that were necessarily part of the mouth opening, in the display of one expression, or mouth closing, in the vanishing of that expression, were nor recorded as separate categories. For instance, iE a child exhibited a broad smile, only this category was recorded.

The frequency of each of the expressive behaviors exhibited by the fo- cal child was recorded. A shorthand record was caken of each event during the session and immediately after the end of the session a brief account was written.

Although all data were collected by the first author, the rehabhty of the categories for both authors during a pilot study gave an agreement of .95.

Following the observational sessions, the teacher was asked to evaluate each child with regard to social competence, happiness, and leadership on a 5-point scale. The higher [he score, the more descriptive was the characteristic of the child. Finally, each child was asked to name one classmate with whom he liked most to play. Both the teacher and the children were assured of the confidenti&ty of their responses. They were not aware of the focus on smiling.

RESULTS AND DISCUSSION A number of clear findings emerged from our naturalistic study of smil-

ing and laughter in preschool children, in which a total of 482 episodes was recorded. First, the frequency per hour of upper smile (M= 18.5 + 1.6) clear- ly predominated over the other expressions. Closed smile (M= 1.1 f 0.4) was the least frequent expression; broad smile (M=2.9 f 0.7) and laughter (M= 2.9 + 0.6) occurred somewhat more frequently, but both were well below the upper smile. This finding is similar to that reported by Cheyne (19761, who found that Canadian preschoolers, observed in a nursery school during free play, exhibited upper smiles (30) more frequently than broad (14) and closed smiles (7) per hour. In our study the frequency per hour of the broad sn~ile was nearer to that of closed smile than in Cheyne (1976). In their laboratory study on facial displays in response to hedonically contrasted odors, Soussig- nan and Schaal (1996) also observed upper smiles (45) more frequently than closed (20) or broad smiles (7) regardless of odor valence. The higher fre-


quency of closed smiles in comparison with both our study and Cheyne's is understandable considering the unpleasant sensory experiences imposed by them on the children.

Our second finding concerned the factor of sex, for which no differences were observed between boys and girls for the various categories of expressive behavior (Table 1). The different types of smiles and laughter were analyzed using a multivariate analysis of variance, with sex as the between- subject factor. The multivariate analysis of variance did not ~ i e ld a significant main effect of sex (Wilks lambda = .96; F,,,, = ,154, p > .05). No differences were found in the frequency of closed smile (F,,,, = ,021, p > .05), upper smile (F ,,,, = ,092, p > .05), broad smile ( F ,,,, = ,453, p > .05), or laughter ( F ,,,, = ,135, p > .05) for boys and girls in the Kmdergarten. As sex was not significant, it was dropped from further analyses.

TABLE 1 MEAN FREQUENCY O F SMILING AND LAUGHTER OF BOYS AND GIRLS

Boys (n: 8) G i r l s 0 7 : 11) M SD IM SD

Closed Smile 1.3 .6 1 .O .5 Upper Smile 18.8 2.5 18.3 2.1 Broad Smile 2.4 1.8 3.3 3.1 Lauehcer 2.6 2.0 3 . 1 3 . 1

Our data are at variance with the adult literature but are in accordance with the literature on children. Whereas among adults women smile more than men in a variety of social contexts (Mackey, 1976; Morse, 1982; Ragan, 1982; MLLls, 1984; Halberstadt, et a l . , 1988), observing American and Cana- dian preschool children during free-play in nursery schools, both Cheyne (1976) and Bainum, et al . (1984) found no differences between boys and girls in s m h g and laughter. Analyzing self-posed behavior in photographs, Otta (1998) found no sex difference in smiling under 5 years of age in a Brazhan sample. Older children, adolescents, and adults were more expressive than preschoolers in this context and significantly more females were seen s m h g than males. It is also interesting to note that Babad, et al . (1983) found no sex difference among preschoolers in the rate of returning a smile to a friendly stranger, neither in America nor in Israel. In older age groups (5-7, 8-10, 11-13, and 14-16 yr.), however, girls smiled substantially more than boys in both countries in spite of the effect of supposed sociabzing agents which may reduce the spontaneous expression of positive affect in Israel.

Females are sociahzed to present themselves in a friendher, more socia- ble, and more appeasing way than males. The course of s m l h g over the life span indicates socialization pressure. Apparently the rule 'put on a happy

PRESCHOOL CHILDREN'S SMILING, LAUGHTER 553

face if you are a female' (Henley, 1977) is not valid for young children. From school age onwards, however, the sex ddference is evident. Boys tend to act in accordance to the tnternalizing mode of emotional expression they were taught, while girls tend to act in accordance to an externahzing mode (Buck, m e r , & Caul, 1974).

In the present research, the frequencies of the three types of smiles and laughter were correlated (Table 2). Closed smile was negatively correlated with upper smile, whereas broad smile and laughter were positively correlated.

TABLE 2 PEARSON CORRELATIONS BETWEEN SMILING AND LAUGHTER (N= 19)

1. Closed Smile -.47* .01 -.20 2. Upper Smile -.07 .22 3. Broad Smile .79t 4. Laughter

*p<.05. tp<.Ol.

The frequencies of the three types of smiles and laughter displayed by the children were factor analyzed with the use of a varimax criterion, and two factors accounted for over 80% of the total variance, with eigenvalues higher than 1.00 (see Table 3). Our cutoff point for interpretation purposes were loadings greater than f .35 (Partington & Grant, 1984; Hair, Ander-

TABLE 3 LOADINGS FROM FACTOR ANALYSIS OF SMILING A N D LAUGHTER (N= 19)

Category Factor 1 Factor 2

Closed Smile .01 -.85* Upper Smile .OO .86* Broad Smile .96* - . I1 Laughter .93" -.22

'Factor loading exceeds 35.

son, Tatham, & Black, 1995). It may be seen that Factor 1 consisted of the broad smile and laughter, and Factor 2 of the closed smile and the upper smile. It is notable that both broad smile and laughter had positive scores on Factor 1, whereas the closed smile and upper smde had opposite scores on Factor 2. The categories had high factor loadmgs ( > 85) on the respec- tive factors, and none of them had high loadings on both factors. In any way, results of this analysis should be interpreted with some caution. Given the small sample size employed here, vahdations with other samples are de- sirable.

S. SARRA & E. OTTA

The present factor analysis suggests that the various types of s m h g and laughter may not just express different intensities of a single emotion. Based on the obtained factor loading pattern, we hypothesized that the first factor reflects ~ la~fu lness or mock aggression (broad smile and laughter) and the second friendliness or appeasement (closed smile and upper smile). Hass (1970) argued that s m h g usually has an element of friendhess or appeasement, whereas laughter usually has an element of aggression. We agree with hinl that laughter is sometimes intended to attack and belittle a person. Dur- ing childhood and adolescence it seems important to learn ways to survive events that threaten the public image and react to embarrassing situations (Leary & Kowalsky, 1995). In our opinion laughter functions as a metacommunicative signal that the ongoing behavior-ither rough-and-tumble play or a remark-is not aggressive (Bateson, 1955; van Hooff, 1972); it is mock aggressive and serves to make the group more and not less cohesive (Bai- num, et a/., 1984).

In the present research, an exploratory quahtative analysis supported our interpretation of the underlying structure of the factor analysis. We ob- sewed that different expressive behaviors occurred in different contexts (cf. Pollio, 1980). The closed smile was seen mainly in nonsocial situations when a child was engaged in solitary play, in agreement with both Blurton-Jones (1972) and Cheyne (1976), or while observing others. Sometimes it was also observed in social situations when a child seemed to be ill at ease, for example, after being called to order or even praised (Otta, 1994).

Alexnndre was wandering alone on the playground. H e smiled (closed smile) as he touched the foliage. H e smiled again (closed smile) observing a group of boys playing football.

There was a sudden rain fall and Marcela ran for cover with a closed smile on her face.

Differently from the other children, Camila and Carolina were not playing during playtime. The teacher approached them and asked, 'And you Cami? Are you also going to stand still?' Camila exhibited a closed smile and lowered her eyes. The teacher said 'These girls look gloomy today!' Camila exhibited another closed smile.

The upper smile was usually seen in social contexts, during verbal interactions, showing of objects, etc. (in agreement with Cheyne, 1976).

With a glacs hll ot water, Beatriz a~proached Luisa and Carol who were playing on the sand area. The p~rl, \LL-re making a cake with sand. Smiling (upper smile) Beatriz asked them 'Do you \inant some water?' Luiza nodded in agreement with an upper smile on her face. Also smiling (upper smile), Beatriz poured water on the sand.

The children were painting their drawings. Marcela takes two colored chalks and smiling (upper smile) offers one to Beatriz, who takes it smiling in reply (upper smile).

Guilherme told Quintela smiling (upper smile) 'Today I vomited on the whole house and stepped on it.' Quintela smiled back (upper smile) 'AARGH!'

Broad smiles and laughter were associated with social contexts of high

PRESCHOOL CHILDREN'S SMILING, LAUGHTER

excitation, for example, during chasing and rough-and- tumble play (see also Brannigan & Hurnphries, 1972; Cheyne, 1976).

Sergio said 'I'm Batman!' and Leonardo answered 'I'm Superrn;m! They broke into a run, with arms open ltke wings, pretending to fly. SPrgio turned hrs face with a broad smile to Leonardo, who was behind him. Leonardo returned a broad smile.

Tanila and Ediane hung upside-down on a climbing-frame. Tarsila looked at Edjane and smiled (broad smile). Edjane returned a broad smile.

Among toddlers, Dickson, et al. (1997) found Iduplay' smiles (corresponding to our broad smile category) more frequently during physical play for fa- ther-infant dyads than for mother-infant dyads. They attributed t h ~ s difference to the fact that fathers tend to engage in high-energy physlcal games, involving wrestling and tumbling, whereas mothers tend to engage in less vigorous actions such as patty-cake.

Other contexts that motivated laughter in the present research were fall- ing down, inept performances, awkward interactions, provocative comments, and conversation about taboo topics.

Quintela took 3 magazine and laughing showed an advertisement of women's undenvear to Guilherme, who returned a broad smile. Renato found a photograph of a wornen wearing rrans- parent lingerie, poincimg to the photograph wirh a broad smile. The three boys laughed and whispered. Guilherme kissed the photograph and smiled (broad smile). Quintela and Renato laughed aloud. Quintela put one hand in front of his face, smiled (broad srnile) and said 'Ah! What a shame!'

Gudherme walked on the playground with hlexandre and Qumtela. A child had vomited and a servant was cleaning the ground. Alexandre srepped in the puddle. Guilherrne looked at him, laughing, and said 'HA! HA! HA! Stepped in! Stepped in!' Alexandre seemed embarrassed and smiled (dosed srnile).

In the present study significant negative associations emerged between closed srnile and teacher's judgement of social competence and happiness (Table 4). Children who exhibited more closed smiles were attributed lower social competence and happiness in comparison with their peers who exhibited less frequently this type of smile.

TABLE 4 PFAFSON CORRELATIONS BETWEEN SMIUNC AND LAUGHTER, TFACHER'S

JUDGEMENT OF SOCIAL COMPETENCE, HAPPINESS AND LEADERSHIP, AND CHILDREN'S NOMINATIONS OF BEST FRIENDS (IV = 19)

Category Social Happiness Leadership Sociometric Competence Status

Closed Smile -.481 -.49t -.38 -.33 Upper Smile .75$ .65$ .69$ .59$ Broad Smile 3 5 .52t .37 .43 Laughter .60$ .66S .70$ .62$

S. SARRA & E. OTTA

A different pattern of results emerged for upper smile and laughter. Large positive associations were found between these expressions and both the teacher's and peers' ratings. The more frequently the child exhibited these behaviors, the more positively he was evaluated. Lower but also positive associations were found between broad smile and teacher's and peers' ratings, significant for happiness and marginally significant for sociometric status.

The pattern of correlations found between expressive behaviors and both the teacher's and peers' evaluations gives further support to the interpretation that s m h g is an heterogeneous category. We suppose that s m h g and laughter emerged as strong correlates of teacher's evaluations and peers' acceptance because these expressive behaviors are not isolated characteristics but part of a network of dispositions and interactional patterns. As pointed out by Leiderman (1983), these expressive behaviors, strongly rooted in the biology of the human organism, may become a characteristic 'signature' of the individual, with varying contributions of temperament, early experience, famhal, and societal reinforcement.

Some children seemed to react frequently with embarrassment in contexts where most of the group reacted with enjoyment. In the context of a music class, for example, during which the teacher invited everybody to dance while singing, almost all children danced vigorously exhibiting broad smiles or laughter, but a minority exhibited an upper smile or even a closed smile. In our opinion the teacher was sensitive to this discrepancy, and the types of smiling and laughter were cues used to infer social competence and well being of a child.

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Accepted October 22, 2001.

Documents

DIFFERENT TYPES OF SMILES AND LAUGHTER IN ... Reports, 2001,89,547-558. O lJsychological Reports 2001 DIFFERENT TYPES OF SMILES AND LAUGHTER IN PRESCHOOL CHILDREN ' SIMONE SARRA AND