Smiling and Laughter: Expressive Patterns

Although smiling and laughter are universal, studying these phenomena is a highly complex process. Unpacking the expressive patterns involved in smiling and laughter helps researchers understand and measure the meaning of the expression being conveyed. For example, when Fredrick Redlich, Jacob Levine, and Theodore Sohler (1951) presented patients with cartoons, they were also interested in the nonverbal responses, which they coded while interacting or from video. Six responses (N = negative response, O = no response, s = halfsmile, S = full smile, C = chuckle, and L = laughter) were identified as important and constituted the “mirth spectrum.” Ordering them according to intensity of response, Edward Zigler, Jacob Levine, and Laurence Gould (1966) created the mirthresponse index. Occasionally, chuckle and negative responses were not included, and often the index ranges from no response (0 points) to half-smile (1 point), smile (2 points), and laughter (3 points), which was assumed by some research as being prototypical and exhaustive.

What was revolutionary 50 years ago is no longer tenable. Negative and positive responses are not on a same dimension and might even blend into one single expression (e.g., disgust jokes). Researchers now doubt that laughter should be scored higher than smiling as they propose that smiling and laughing signify different things and thus should not be included in the same index. Importantly, types of smiles, laughter, and negative responses do matter for a comprehensive understanding, but researchers do not believe that words carry the information. Rather, researchers believe it is important to provide accurate morphological observation, that is, how the laughter or smile is created. Moreover, current assessment tools are used for all body movement or all facial actions and are not restricted to smiling and laughter. This entry discusses how researchers measure and classify smiles and laughter as well as the emotions expressed through smiles and laughter and other nonverbal gestures.