Do Children Laugh Much More Often than Adults Do?

Article by Rod A. Martin

We often hear the claim that children laugh much more frequently than adults do. Many numbers are thrown around, but I've heard some claims that children laugh more than 300 times a day, whereas adults laugh less than 20 times a day. The implication is that somehow people become too serious and lose the ability to laugh while growing up, and adults should try to regain the lost joy of childhood by becoming more playful and humorous. Although I certainly agree that we adults are often too serious and we might benefit from laughing more often, I have not been able to find the scientific research that these numbers supposedly came from. I have found only a handful of studies that examined frequencies of laughter in children and adults, and these do not support the numbers typically cited. In fact, the existing studies suggest that adults may actually laugh more often than children!

Laughter in adults during social interactions with friends and strangers

In one study, my colleague Nicholas Kuiper and I at the University of Western Ontario asked adult participants to record each time they laughed over the course of three days. We found an average of about 17 reported laughs per day in adults, with a range of 0 to over 80 laughs (Martin & Kuiper, 1999). No differences were found between men and women in the average frequency of laughter overall. However, this self-report method may have underestimated the number of times adults actually laugh. When asked to keep a record of their own laughter, people may fail to record all instances of laughter and may not even notice some of the times when they are laughing.

A more accurate method is to actually observe people and count how often they laugh. Of course we would have to have some agreed-upon definition of what constitutes a single laugh. Unfortunately, there doesn't seem to be any research that has followed people around for a whole day to observe how often they laugh! It's more feasible to observe people's laughter during shorter time samples and extrapolate from there. In what circumstances should we observe people to determine their laughter frequency? There is abundant evidence that laughter occurs much more often when people are engaged in social interactions with others than when they are alone. For example, Robert Provine (1989) at the University of Maryland found that people are 30 times more likely to laugh when they are with others than when alone. Thus, laughter is essentially a social behavior, a form of nonverbal communication. To maximize the likelihood of observing laughter, it therefore makes sense to observe people when they are interacting with others. However, to extrapolate from these observations to the entire day, we need to take into account the fact that people are engaged in social interactions for only a portion of the day, and therefore our observed rates will be much higher than what they would be over the whole day.

The only study of this kind that I have found is one by Julia Vettin and Dietmar Todt (2004), at the Free University of Berlin, Germany, who tape recorded a total of 48 hours of conversations among numerous pairs of friends and strangers in naturalistic settings. They found an average of 5.8 bouts of laughter occurring in each 10-minute period of conversation, with a range of 0 to 15 bouts per 10-minute period (which translates to an average of about 35 bouts of laughter per hour). A bout of laughter was defined as the laughter occurring during a single exhalation. Thus, each time a person inhales and laughs again, this is counted as another bout. Surprisingly, the average frequency of laughter did not differ in the conversations of friends compared to strangers. These data, then, suggest fairly high average rates of laughter when adults are engaged in conversations with either friends or strangers. We would need to know how many minutes per day, on average, people are engaged in such conversations with others to extrapolate from these data and calculate the overall daily frequency of adult laughter (I don't have these numbers).

As a matter of interest, here are a few more interesting findings from this study, which further highlight the social nature of laughter. Individuals laughed more frequently following something they themselves said than following something said by their conversational partner. Also, speakers generally waited until the end of their own sentences before laughing (i.e., they did not laugh in the middle of a sentence), but listeners often laughed while their conversational partners were still speaking. Acoustical analyses also revealed a great deal of variability in the sound qualities of laughter, both within and between individuals (cf. Bachorowski, Smoski, & Owen, 2001). In addition, it was found that some of the acoustical parameters of laughter varied systematically according to the context and whether the laughter was produced by the speaker or the listener. These findings highlight the conversational nature of laughter, indicating that it is a nonverbal method of communicating information.

Laughter in infants interacting with their mothers

Research by Eva Nwokah and her colleagues at Purdue University has investigated in some detail the social nature of laughter as a means of communicating emotional information between infants and their caregivers. In one study, Nwokah and her colleagues (1994) conducted a longitudinal study in which they observed the laughter of mothers as well as their infants during a series of free play sessions over the first two years of the infants' lives, to examine the timing parameters and temporal sequence of laughter in interpersonal interaction. They found that infant laughter increased in frequency over the first year and remained fairly stable during the second year. Between 1 and 4 months of age, infants laughed an average of only .08 times per minute during interactions with their mother. By 1 year of age, this had increased to .27 laughs per minute, and leveled off at .30 per minute by two years (equaling 18 laughs per hour). In contrast, the rate of laughter in the mothers remained quite stable over the two years, at around .55 laughs per minute (or 33 per hour). Note that mothers' laughter was nearly twice as frequent as infants' laughter (and was similar to the frequency of adult-to-adult laughter during conversations found in the previously-described study). Interestingly, by the second year, the rate and duration of laughter was significantly correlated between mothers and their infants, meaning that the more a particular mother laughed, the more her infant also laughed. Thus, laughter appears to be modeled by the mother during the first year and stabilizes in the infant by the second year.

Laughter in 3- to 5-year-old children during free play periods

As children progress into the preschool or nursery school years, their laughter occurs increasingly in the context of playful interactions with other children in addition to caregivers. Charlene Bainum and her colleagues at the University of Tennessee   (Bainum, Lounsbury, & Pollio, 1984) observed groups of 3-, 4-, and 5-year-old children in a nursery school to evaluate the frequency of occurrence and conditions surrounding laughing and smiling during structured and unstructured play. No differences were found between girls and boys in the overall frequency of smiling and laughter across the three age groups. The social nature of smiling and laughter was again clearly demonstrated by the fact that 95 percent of these behaviors occurred when the child was interacting with others, and only 5 percent when the child was alone. Laughter increased in frequency from age 3 to 5, whereas smiling decreased in frequency over this age span. By the age of 5, children were observed to laugh an average of 7.7 times per hour during play.

Interestingly, the stimuli producing laughter also changed with age. Laughter in younger children occurred more often in response to amusing nonverbal actions (e.g., funny faces or body movements), whereas laughter in older children appeared more frequently in response to amusing verbal utterances (e.g., funny comments, stories, songs, or unusual word usage). In all three age groups, laughter occurred most frequently in response to intentionally-produced silliness/ clowning events, in which children engaged in verbal and nonverbal behavior with the apparent intention of causing a laugh response. Thus, laughter appears to be primarily a response to intentional humor rather than events that are unintentionally funny. Interestingly, children were somewhat more likely to laugh at their own funny physical and verbal behaviors than at those of others, indicating that laughter was often used as a signal to indicate that particular behaviors were meant to be funny (cf. the finding that adults tend to laugh more at things they themselves say than at things other people say). Although the majority of laughter occurred in response to socially positive or at least neutral humorous behavior, there was an increase from age 3 to 5 in the proportion of laughter occurring in response to socially negative behaviors such as teasing, shoving, or ridicule.

Summary:

Although these research findings are quite limited, overall they don't support the idea that adults and children show hugely different rates of laughter. Both adults and children laugh primarily during social interactions with others. Consequently, the frequency of laughter at any age depends on how much time an individual spends interacting with others. Among children as well as adults, those who are more extraverted tend to laugh more often than do introverts. Beginning in infancy and continuing to adulthood, laughter appears to be primarily a form of non-verbal communication by which people express their feelings of amusement and joy to one another. If anything, the existing evidence suggests that adults may laugh more often than children do! Two-year-old infants laugh an average of about 18 times an hour during interactions with their mothers, whereas their mothers laugh almost twice as often, at about 33 laughs per hour. Five-year-old children apparently laugh only about 8 times an hour during play (the activity in which they would be expected to laugh most freely). In adults, laughter occurs about 35 times an hour - 4 times as often as what was observed in children - during conversations with either friends or strangers.

One problem with these data is that single instances of laughter were not defined the same way in all studies. The Nwokah et al. and the Vettin and Todt studies counted "laughter bouts" (laughter occurring during a single exhalation), whereas the Bainum et al. study counted "humor events" (discrete verbal or behavioral actions of a child that were followed by audible laughter in the same or another child). Some of these events may have involved more than one laughter "bout," or exhalation, resulting in a lower overall rate than would have been found if bouts had been counted. This difference in measurement approaches may therefore account in part for the lower average laughter frequency found among children in this study. However, even if we allow for the possibility of an average of four laughter "bouts" in each episode (which seems generous), this would still only bring the average frequency of laughter in children up to the level observed in adults. Overall, then, the research that I have been able to locate doesn't support the huge discrepancies between frequencies of adult and child laughter that are often claimed. At the same time, it's important to note that the existing research on this topic is quite limited, and this is certainly one of those areas in which "further research is needed."

References:

Bachorowski, J.-A., Smoski, M. J., & Owen, M. J. (2001). The acoustic features of human laughter. Journal of the Acoustical Society of America , 110(3,Pt1), 1581-1597.

Bainum, C. K., Lounsbury, K. R., & Pollio, H. R. (1984). The development of laughing and smiling in nursery school children. Child Development, 55(5), 1946-1957.

Martin, R. A., & Kuiper, N. A. (1999). Daily occurrence of laughter: Relationships with age, gender, and Type A personality. Humor: International Journal of Humor Research, 12(4), 355-384.

Nwokah, E. E., Hsu, H.-C., Dobrowolska, O., & Fogel, A. (1994). The development of laughter in mother-infant communication: Timing parameters and temporal sequences. Infant Behavior & Development, 17(1), 23-35.

Provine, R. R., & Fischer, K. R. (1989). Laughing, smiling, and talking: Relation to sleeping and social context in humans. Ethology, 83(4), 295-305.

Vettin, J., & Todt, D. (2004). Laughter in conversation: Features of occurrence and acoustic structure. Journal of Nonverbal Behavior, 28(2), 93-115.