When do gestures communicate? A meta-analysis

Do the gestures that speakers produce while talking significantly benefit listeners' comprehension of the message? This question has been the topic of many research studies over the previous 35 years, and there has been little consensus. The present meta-analysis examined the effect sizes from 63 samples in which listeners' understanding of a message was compared when speech was presented alone with when speech was presented with gestures. It was found that across samples, gestures do provide a significant, moderate benefit to communication. Furthermore, the magnitude of this effect is moderated by 3 factors. First, effects of gesture differ as a function of gesture topic, such that gestures that depict motor actions are more communicative than those that depict abstract topics. Second, effects of gesture on communication are larger when the gestures are not completely redundant with the accompanying speech; effects are smaller when there is more overlap between the information conveyed in the 2 modalities. Third, the size of the effect of gesture is dependent on the age of the listeners, such that children benefit more from gestures than do adults. Remaining questions for future research are highlighted.     

Do captive mandrills invent new gestures?

Studies of intraspecific behavioral variability have documented cases where behaviors are present in some populations or groups but are absent in others. In some cases these differences cannot be explained by recourse to environmental or genetic variation, and may instead represent “traditions”. Despite many examples of animal traditions in acoustic communication, relatively few examples exist of gestural traditions. Here I report on a study of communication across eight captive groups of mandrills (Mandrillus sphinx) in which a prominent gesture (Hand extension) was unique to two groups. Habitat variability, genetic differences, and sampling bias were not sufficient to account for the gesture’s limited distribution across the study groups. Within the two groups where the gesture did occur only the juveniles in the group performed it, consistently directing it toward adults. Quantitative analysis of the contexts and responses associated with the gesture suggested that juveniles utilized it to provoke adults. Moreover, the gesture appeared to minimize the risk juveniles incurred while inciting adults, suggesting that repeated social interactions shaped the gesture’s form. Interestingly, both the groups where the gesture emerged contained few juveniles. With limited play partners, these juveniles may have resorted to harassing adults as an alternative social play outlet. The creation of this novel gesture may thus be due to the combined influence of a shortage of play partners and of the increased free time for playful social exploration afforded by captivity. Although juveniles frequently “eavesdropped” on dyadic interactions involving the gesture and would subsequently initiate an interaction with the recipient of the gesture, there was no definitive evidence for social transmission; the gesture could instead have been independently invented by each juvenile. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Do readers make inferences about conversational topics?

When we read that two protagonists in a story chatted together for a couple of minutes, do we draw inferences about the topic of the conversation on the basis of information presented earlier in the text? Participants read passages in which protagonists part and later reunite; the passages ended with a sentence either that implied conversation or did not. In Experiment 1, participants' continuation sentences indicated that inferences about the topic of conversation were drawn. Recognition probe data in Experiment 2 provided more immediate evidence of such inferences. Experiment 3 addressed a possible confound in Experiment 2 and again provided evidence that readers inferred the continuation of the conversation. In Experiments 4 and 5, we investigated the effect of having the targeted conversational topic be a secret that should not be shared between the protagonists. The results are discussed in terms of the collaboration between passive, memory-based text processing and schema-driven comprehension processes.     

Do private gestures have a self-regulatory function? A case study

One of the most fascinating phenomena in early development is that babies not only understand signs others direct to them and later use them to communicate with others, but they also come to direct the same signs towards themselves in a private way. Private gestures become "tools of thought". There is a considerable literature about private language, but almost nothing about private gestures. Private gestures pose an intriguing communicative puzzle: they are communicative, but with the self. In this paper we study two types of private gestures (signs) before language: (1) private ostensive gestures and (2) private pointing gestures. We show in a case study of one child between 12 and 18 months of age that both are used with a self-reflexive function, as a way of "thinking" what to do, in order to solve a problem in the conventional use of an object. The private gestures become self-reflexive signs.     

Do pointing gestures by infants provoke comments from adults?

In the field of developmental psychology, there is speculation that pointing gestures by infants are good precursors of infant language acquisition, and some researchers have found correlations between these pointing gestures and some indices of language acquisition. Infants’ pointing gestures are presumably related to language acquisition because they provoke verbal responses from adults. To test this, seven boys and six girls were observed during free play time in a nursery classroom, and post-pointing and matched-control data were collected. Comparison between these data confirmed that the nursery staff spoke to infants at a significantly earlier stage in post-pointing sequences, compared with control sequences, indicating that pointing gestures elicit verbal responses from adult caregivers.     

Movement and lexical access: Do noniconic gestures aid in retrieval?

The production of meaningful gestures has been claimed to enhance lexical access. However, the possibility that meaningless movements also improve retrieval has been largely ignored despite evidence that all types of movements increase with dysfluency. To examine this issue, we conducted two experiments to determine whether movements in general would improve lexical access in a tip–of–thetongue (TOT) paradigm. TOT states were induced by presenting definitions of rare words that participants were then asked to recall. Participants who were required to tap at their own pace while retrieving words obtained significantly higher resolution rates than those who were immobile. Thus, movement does not have to be semantically related to the lexical item in order to aid in retrieval. However, tapping did not improve lexical access in all retrieval tasks. In a lexical retrieval task that relied more on executive abilities (letter fluency), participants who tapped retrieved fewer words than those who were immobile. The fact that movement enhanced lexical access only when retrieval depended on the automatic spread of activation suggests that facilitation may occur because of the activation of neural areas common to both speech and movement.     

Do 6‐month‐olds understand that speech can communicate?

Adults and 12‐month‐old infants recognize that even unfamiliar speech can communicate information between third parties, suggesting that they can separate the communicative function of speech from its lexical content. But do infants recognize that speech can communicate due to their experience understanding and producing language, or do they appreciate that speech is communicative earlier, with little such experience? We examined whether 6‐month‐olds recognize that speech can communicate information about an object. Infants watched a Communicator selectively grasp one of two objects (target). During test, the Communicator could no longer reach the objects; she turned to a Recipient and produced speech (a nonsense word) or non‐speech (coughing). Infants looked longer when the Recipient selected the non‐target than the target object when the Communicator spoke but not when she coughed – unless the Recipient had previously witnessed the Communicator's selective grasping of the target object. Our results suggest that at 6 months, with a receptive vocabulary of no more than a handful of commonly used words, infants possess some abstract understanding of the communicative function of speech. This understanding may provide an early mechanism for language and knowledge acquisition.     

Why do gorillas make sequences of gestures?

Great ape gestures have attracted considerable research interest in recent years, prompted by their flexible and intentional pattern of use; but almost all studies have focused on single gestures. Here, we report the first quantitative analysis of sequential gesture use in western gorillas (Gorilla gorilla gorilla), using data from three captive groups and one African study site. We found no evidence that gesture sequences were given for reasons of increased communicative efficiency over single gestures. Longer sequences of repeated gestures did not increase the likelihood of response, and using a sequence was seldom in reaction to communicative failure. Sequential combination of two gestures with similar meanings did not generally increase effectiveness, and sometimes reduced it. Gesture sequences were closely associated with play contexts. Markov transition analysis showed two networks of frequently co-occurring gestures, both consisting of gestures used to regulate play. One network comprised only tactile gestures, the other a mix of silent, audible and tactile gestures; apparently, these clusters resulted from gesture use in play with proximal or distal contact, respectively. No evidence was found for syntactic effects of sequential combination: meanings changed little or not at all. Semantically, many gestures overlapped massively with others in their core information (i.e. message), and gesture messages spanned relatively few functions. We suggest that the underlying semantics of gorilla gestures is highly simplified compared to that of human words. Gesture sequences allow continual adjustment of the tempo and nature of social interactions, rather than generally conveying semantically referential information or syntactic structures.     

Do proposed facial expressions of contempt, shame, embarrassment, and compassion communicate the predicted emotion?

Shame, embarrassment, compassion, and contempt have been considered candidates for the status of basic emotions on the grounds that each has a recognisable facial expression. In two studies (N=88, N=60) on recognition of these four facial expressions, observers showed moderate agreement on the predicted emotion when assessed with forced choice (58%; 42%), but low agreement when assessed with free labelling (18%; 16%). Thus, even though some observers endorsed the predicted emotion when it was presented in a list, over 80% spontaneously interpreted these faces in a way other than the predicted emotion.     

Is the hand to speech what speech is to the hand?

Interference between the manual and the verbal performance on two types of concurrent verbal-manual tasks was studied on a sample of 48 female right-handers. The more complex verbal task (storytelling) affected both hands significantly, the less complex (essentially phonemic) task affected only the right hand, with insignificant negative influence on the left-hand performance. No significant reciprocal effects of the motor task on verbalization were found.     

Do low burnout and high work engagement always go hand in hand?: investigation of the energy and identification dimensions in longitudinal data

The aim of the present 2-year follow-up study among young managers (N=433) was to investigate the intraindividual developmental patterns of burnout and work engagement as well as their interconnections. More specifically, we examined the interconnectedness of the varying patterns (i.e., latent classes) of exhaustion and vigor (i.e., the energy dimension) and cynicism and dedication (i.e., the identification dimension) across time. The latent class solutions supported by the growth mixture modeling indicated four latent classes for exhaustion and five for vigor. In addition, four latent classes were found for cynicism and six for dedication. Cynicism and dedication represented opposites with a strong negative relationship, whereas exhaustion and vigor were not connected and seemed to be two independent constructs. Overall, the present findings confirmed the results of earlier studies relating to the energy and identification continua and underlined the importance of investigating the subdimensions of burnout and work engagement. Thus, our study showed that high cynicism goes hand in hand with low dedication, but high exhaustion and low vigor do not necessarily appear together.     

Does the intention to communicate affect action kinematics?

The aim of the present study was to investigate the effects of communicative intention on action. In Experiment 1 participants were requested to reach towards an object, grasp it, and either simply lift it (individual condition) or lift it with the intent to communicate a meaning to a partner (communicative condition). Movement kinematics were recorded using a three-dimensional motion analysis system. The results indicate that kinematics was sensitive to communicative intention. Although the to-be-grasped object remained the same, movements performed for the ‘communicative’ condition were characterized by a kinematic pattern which differed from those obtained for the ‘individual’ condition. These findings were confirmed in a subsequent experiment in which the communicative condition was compared to a control condition, in which the communicative exchange was prevented. Results are discussed in terms of cognitive pragmatics and current knowledge on how social behavior shapes action kinematics.     

Are number gestures easier than number words for preschoolers?

Some researchers have argued that children's earliest symbols are based on their sensorimotor experience and that arbitrary symbol-referent mapping poses a challenge for them. If so, exposure to iconic symbols (such as one-finger-for-one-object manual gestures) might help children in a difficult domain such as number. We assessed 44 preschoolers’ processing of number gestures and number words on two tasks: give-a-number and how-many. Children were generally more accurate when mapping number words than number gestures onto a number of toys, suggesting that the iconicity of number gestures does not help children map symbols to numbers. We argue that children learn number gestures as arbitrary symbols and do not take advantage of their iconicity.     

Does object modeling elicit imitative-like gestures from young infants?

One interpretation of the evidence for early imitative-like matching of facial gestures is that the acts are elicited by stimulus properties, rather than constructed by the infant. Verification of this possibility requires presentation of object models to determine whether infants reliably respond to them with movement-matching gestures. Two object models, one simulating tongue movements and the other mouth opening/closing, were presented to younger infants (median age = 5 weeks) and to older ones (median age = 12 weeks) under systematically varied movement conditions. Additionally, a live model presented tongue protrusion and mouth opening gestures to the same infants. Findings of two studies were similar. At neither age was there reliable elicitation of facial gestures by either object model, which suggests that most infants were not imitating the object movements or responding to them in a way that verifies elicitation of facial matches by object presentation. Live modeling of tongue extensions, however, did increase the incidence of partial tongue protrusions among infants at 5 weeks, which supports previous research.     

Where have all the (ape) gestures gone?

Comparative analysis of the gestural communication of our nearest animal relatives, the great apes, implies that humans should have the biological potential to produce and understand 60–70 gestures, by virtue of shared common descent. These gestures are used intentionally in apes to convey separate requests, rather than as referential items in syntactically structured signals. At present, no such legacy of shared gesture has been described in humans. We suggest that the fate of “ape gestures” in modern human communication is relevant to the debate regarding the evolution of language through a possible intermediate stage of gestural protolanguage.     

What Do We Do Unconsciously? And How?

In this reply, we endorse Chartrand's (2005) taxonomy of conscious awareness for different stages of consumer decisions affected by environmental cues. In addition, we attempt to broaden the scope of this taxonomy by discussing its usefulness for consumer decisions in general. We generally support Simonson's (2005) claim that research based on consumers as conscious decision makers is indeed predictive of a wide variety of behavior. However, we also argue that the importance of consciousness should not be overstated. Conscious processes observed in a research laboratory are not representative of conscious processes in real life. The alternative model to describe effects of the environment on behavior by Janiszewski and van Osselaer (2005) may be useful to explain automaticity in goal‐directed behavior, but it poorly describes other automatic behaviors.