Gestures

Abstract

Gestures are a form of kinesics, the meaning-bearing movements of the hands and body, and the most studied channel of body motion in cognitive psychology. Their scientific study began with David Efron, who showed that gestural style is shaped by culture rather than race, and matured through David McNeill's four-way classification of co-speech gesture and Adam Kendon's continuum from spontaneous gesticulation to conventional sign. Modern research treats the hand movements that accompany speech not as decoration but as one gesture-speech system, synchronized with the words and springing from a shared idea. Much of it, from Susan Goldin-Meadow and her collaborators, shows that gesture can carry information the speaker never puts into words, reveal knowledge on the verge of emerging, and make learning last. Three demonstrations present gestures as a repertoire, a component of thought, and an aid to learning.

Keywords: gestures, co-speech gesture, gesture-speech integration, iconic gesture, gesture and learning

When people talk, their hands move. The movement is nearly universal, largely involuntary, and oddly persistent — people gesture on the telephone, in the dark, and from birth blindness, where no listener can see them. That stubbornness is the first clue that gesture is not simply a performance aimed at an audience but something bound up with speaking and thinking themselves. Cognitive psychology approaches gesture with three questions. What are the kinds of gesture, and how do they relate to the words they accompany? What does gesture do for the person who watches it — does it genuinely add to comprehension? And what does gesture do for the person who produces it — does moving the hands help the speaker think, learn, and find words? The sections that follow take these in turn. The recurring finding is that gesture is neither mere ornament on speech nor a separate sign language running alongside it, but an integral part of how humans package and exchange meaning.

What Gestures Are

A gesture is a movement of the body, most often the hands and arms, that carries communicative or representational meaning. Gesture is one of the channels that make up kinesics, the broader study of body motion as communication; where kinesics also takes in posture, facial movement, and gaze, the study of gesture proper concerns the expressive actions of the hands and limbs. Its scientific study begins with David Efron, whose Gesture and Environment compared the gesturing of first- and second-generation immigrant communities in New York and showed that gestural style tracks culture and assimilation rather than ancestry — a direct empirical refutation of the then-current racial theories of gesture, and the founding demonstration that gesture is learned and socially patterned (Efron, 1941). Paul Ekman and Wallace Friesen later placed gesture within their general taxonomy of nonverbal behavior, distinguishing emblems — gestures with a direct verbal translation, such as a thumbs-up, that can stand in for words — from illustrators, the gestures that accompany and depict speech (Ekman & Friesen, 1969).

The classification that organizes most current research is David McNeill's, which sorts the gestures that accompany speech into four kinds (McNeill, 1992). An iconic gesture depicts concrete content — tracing the path of a rolling ball, or miming the turning of a crank — so that its form resembles what it represents. A metaphoric gesture depicts an abstraction by giving it a spatial vehicle, as when a speaker cups the hands to present an idea as an object held out for inspection. A deictic gesture points, locating a referent in real or imagined space. A beat is a short, rhythmic flick of the hand that marks the structure of speech rather than its content, falling on words the speaker wishes to foreground. These kinds are not sharply exclusive — a single gesture can point and depict at once — but they capture how differently the hands can mean. Adam Kendon arranged a related set of distinctions on a continuum, from the spontaneous gesticulation that accompanies ordinary talk, through language-like and pantomimic gestures, to the fully conventionalized signs of a sign language, with speech-dependence falling and conventionalization rising along the way (Kendon, 2004). The first demonstration presents McNeill's four categories and lets the reader classify example gestures.

Read the utterance and the hand movement that accompanies it, then choose which of McNeill’s four kinds it is.

Note. The kinds are not sharply exclusive — a single gesture can point and depict at once — but each example here has one clearest reading. Classification after McNeill (1992).

Gesture and Speech

The central claim of modern gesture research is that co-speech gesture and the speech it accompanies form a single system rather than two parallel channels. David McNeill's Hand and Mind assembled the evidence: gestures are produced in tight temporal synchrony with the speech they relate to, their most effortful phase falling on or just before the word that carries the matching meaning; they are disrupted together with speech in stuttering and aphasia; and they express the same underlying idea in a complementary form (McNeill, 1992). McNeill proposed that an utterance begins as a growth point, a minimal unit in which imagery and linguistic content are briefly fused, and that gesture and speech are the two channels into which this shared seed is unpacked — the gesture rendering the imagistic, holistic side, the speech rendering the analytic, sequential side. On this account a gesture is not a translation of the sentence but a window onto the thought the sentence is still assembling. Kendon's analysis reached a compatible conclusion from the side of communication: visible bodily action is deployed by speakers as an integral part of the utterance, planned and timed together with speech to form a single multimodal package (Kendon, 2004).

Because gesture and speech spring from a shared representation, the two can also come apart in revealing ways. When a gesture expresses information that the accompanying speech does not — a gesture-speech mismatch — the mismatch is not noise but signal: it frequently marks a speaker, especially a child, who holds more than one idea about a problem and is on the verge of change. Jana Iverson and Susan Goldin-Meadow found that gesture leads the way into language itself: the objects and actions a child first indicates in gesture predict which words will soon enter the child's speech, so that gesture paves the way for the vocabulary that follows (Iverson & Goldin-Meadow, 2005). Marian Novack and Goldin-Meadow later recast gesture of this kind as representational action — action that has been schematized and stripped of direct effect on the world, so that it represents rather than does, which is what lets it carry meaning forward into thought and language (Novack & Goldin-Meadow, 2017). The second demonstration shows how a gesture can express a problem-solving strategy that the speaker's words leave out.

Two children explain their answer to the same equivalence problem. Reveal each channel in turn and see whether the hands agree with the speech.

Note. The equivalence problem and the strategy types follow Goldin-Meadow’s studies of gesture and learning. A mismatcher’s hands reveal a correct grouping idea before speech can state it, which is why such children profit most from instruction. Fixed illustrative cases.

Gesture, Thought, and Learning

If gesture and thought are linked at their source, then producing gesture should affect the gesturer, not only the observer — and it does. Susan Goldin-Meadow's program established that gesture is a route into a learner's mind and a lever on learning. Children explaining how they solved a problem often reveal in their hands a correct strategy that is absent from their speech; those who produce such speech-gesture mismatches are the ones most ready to profit from instruction, so a teacher who watches the hands can see readiness to learn before it surfaces in words (Goldin-Meadow & Alibali, 2013). Gesture does not only diagnose learning; it promotes it. Susan Wagner Cook and colleagues taught children a mathematical principle with or without gesture and tested them weeks later: the children who had gestured during learning retained far more of what they had gained, so that, as the title of the study put it, gesturing makes learning last (Cook et al., 2008).

Why producing gesture should help the producer is itself an active question, addressed in the Current Directions below, but the working answer is that gesture externalizes and lightens thought — giving spatial and motor ideas a bodily form that is cheaper to hold and manipulate than a purely verbal one. That gesture also helps the listener is well established. Spencer Kelly, Asli Özyürek, and Eric Maris showed that speech and gesture interact bidirectionally in comprehension: a gesture speeds and sharpens the understanding of the speech it accompanies, and the speech in turn constrains how the gesture is read, so that neither is processed in isolation (Kelly et al., 2010). The size of gesture's benefit to comprehension has been estimated by meta-analysis, which is the subject of the worked example and the third demonstration; the benefit is reliable but moderate, and it depends on what the gesture depicts and on the learner (Hostetter, 2011; Dargue et al., 2019).

Drag the effect size d and watch it become the common-language effect size: the chance a randomly chosen learner who saw gesture understood better than one who did not.

Note. At d = 0 the two conditions are identical and the chance is 50%. A moderate effect of d = 0.6 gives about 66%; a strong concrete-content effect near d = 0.9 reaches about 74%; a weak abstract effect of d = 0.2 is barely above a coin toss at about 56%. The conversion is exact for two equal-variance normal distributions; the effect sizes are illustrative (Hostetter, 2011; Dargue et al., 2019).

Table 1

What Gesture Does, for Observer and for Gesturer

Note. The functions are not rivals. A single gesture during a lesson can communicate content to a listener, reveal the speaker's readiness to learn, and help the speaker organize the thought at once.

Worked Example

Meta-analyses of gesture report their results as a standardized effect size, Cohen's d, which expresses a difference between two conditions in units of standard deviation. For gesture's effect on comprehension and learning the reported values cluster in the moderate range; take a representative value of d = 0.6. A number like 0.6 is hard to feel, so it helps to convert it into something concrete: the common-language effect size (CLES), the probability that a person drawn at random from the gesture condition scores higher than a person drawn at random from the no-gesture condition.

For two normal distributions with equal variance, that probability is Φ(d / √2), where Φ is the standard-normal cumulative distribution. With d = 0.6, the difference is scaled by √2 ≈ 1.414, giving 0.6 / 1.414 ≈ 0.424. Reading the standard-normal table at 0.424 gives Φ(0.424) ≈ 0.664. So a moderate gesture effect of d = 0.6 means that about 66% of the time, a randomly chosen learner who saw gesture understood better than a randomly chosen learner who did not — a coin that comes up in gesture's favor two times in three, not the near-certainty that the word significant sometimes suggests. The same formula makes the moderators vivid. A gesture about concrete motor content might reach d = 0.9, giving Φ(0.9 / 1.414) = Φ(0.636) ≈ 0.738, roughly a 74% advantage; a gesture about an abstract topic might manage only d = 0.2, giving Φ(0.141) ≈ 0.556, barely better than the 50% of a fair coin. The representative figures here are illustrative rather than exact meta-analytic estimates, but the conversion is exact, and it captures why gesture's documented benefit is real, worth exploiting in teaching, and yet far from guaranteed on any single occasion (Hostetter, 2011; Dargue et al., 2019). The third demonstration implements this conversion.

Discussion

The three questions that open this article have converging answers. Gesture is a classifiable repertoire — iconic, metaphoric, deictic, and beat, arranged on a continuum from spontaneous movement to conventional sign — whose study began when Efron proved it to be cultural rather than innate and which Ekman and McNeill and Kendon turned into a working taxonomy. Gesture communicates to observers, moderately and selectively, best when it is concrete and adds to the words. And gesture serves its producer, externalizing thought, revealing knowledge before speech can, and deepening what is learned. What ties the three together is the founding claim of the modern field: that gesture and speech are not two systems but one, drawing on a shared representation and expressed in two complementary forms.

This integration is what distinguishes the cognitive-psychological study of gesture from both the folk tradition of body language and the linguistics of sign. Against the folk view, gesture is not a leak of hidden feeling that a trained eye can read like print; it is a structured, largely communicative component of utterance whose information is real but bounded. Against an assimilation to sign language, co-speech gesture is not a language — it lacks a stable lexicon and a combinatorial grammar — but it is language's constant partner, and the two are planned, timed, and understood together. The practical upshot, visible across the learning studies, is that attending to the hands, in oneself and in others, is attending to thought in a form that speech has not yet fully captured.

Current Directions

The most active question is why producing gesture helps the gesturer think. An earlier and narrower proposal, Robert Krauss's lexical-retrieval hypothesis, held that gesture's benefit to the speaker is not conceptual but lexical: the spatial and motor features a gesture renders help prime and retrieve the word the speaker is searching for, which is why gesticulation often rises when speech stalls over a hard-to-find term (Krauss, 1998). Sotaro Kita, Martha Alibali, and Mingyuan Chu's gesture-for-conceptualization hypothesis widens that claim: representational gesture helps a speaker schematize and package spatial, motor, and perceptual information into the units that speaking and problem-solving require, so that the hands actively shape the thought rather than merely expressing a finished one (Kita et al., 2017). A closely related framework from Autumn Hostetter and Martha Alibali, gesture-as-simulated-action, grounds gesture in embodied cognition: thinking and speaking recruit perceptual and motor simulations, and when those simulations are strong enough they spill over into visible movement, which predicts both when people gesture and what their gestures look like (Hostetter & Alibali, 2019). The two accounts are being tested against each other and against the accumulating meta-analytic record of when gesture does and does not aid comprehension and learning (Dargue et al., 2019).

A second strand enlarges the frame from gesture-and-speech to multimodal language. Judith Holler and Stephen Levinson argue that face-to-face communication is processed as a single integrated signal, in which bodily visual cues and speech are bound together and can even speed comprehension, so that gesture belongs to the core architecture of human language rather than to its margins (Holler & Levinson, 2019). On this view the integration McNeill posited within the individual speaker extends outward to the rapid, multimodal coordination of conversation itself. Both strands move the study of gesture away from cataloguing hand shapes and toward explaining how body and speech constitute one system for thinking and for talking.

Common Misconceptions

Gestures are just decoration added to the real message in words.

Co-speech gesture is synchronized with speech, springs from a shared idea, and can carry information the words omit; it can even reveal knowledge the speaker cannot yet put into words. It is part of the utterance and of thinking, not an optional flourish (McNeill, 1992; Goldin-Meadow & Alibali, 2013).

Gesture is a universal language anyone can read.

Emblems and conventional gestures are culturally specific and learned — the very point Efron established by showing gestural style tracks culture, not ancestry (Efron, 1941). Co-speech gesture is also not a language in its own right: it lacks a stable lexicon and a grammar, and is understood only together with the speech it accompanies (Kendon, 2004).

Watching someone's hands reveals what they really feel or whether they are lying.

Gesture's communicative value is real but bounded and depends on what it depicts; meta-analysis puts the overall effect on comprehension at a moderate level, far from a transparent readout of a speaker's inner state (Hostetter, 2011; Dargue et al., 2019).

Glossary

Beat.

A short, rhythmic flick of the hand that marks the prosodic structure of speech rather than depicting content, often falling on emphasized words.

Co-Speech Gesture.

A spontaneous hand movement produced together with speech and synchronized to it, forming part of a single gesture-speech system.

Deictic Gesture.

A pointing gesture that locates a referent, concrete or abstract, in real or imagined space.

Emblem.

A gesture with a direct verbal translation, such as a thumbs-up, that can substitute for words; typically culturally specific.

Gesticulation.

The spontaneous, idiosyncratic hand movement that accompanies ordinary talk; the speech-dependent, least conventionalized end of Kendon's continuum.

Gesture-as-Simulated-Action.

Hostetter and Alibali's framework in which gestures arise when the perceptual and motor simulations underlying thought and speech are strong enough to spill into movement.

Gesture-for-Conceptualization.

Kita, Alibali, and Chu's hypothesis that representational gesture helps the speaker schematize and package spatial and motor information for speaking and thinking.

Gesture-Speech Mismatch.

A moment at which a speaker's gesture expresses different information from the accompanying speech, often marking readiness to learn.

Growth Point.

McNeill's term for the shared idea unit, fusing imagery and linguistic content, from which a co-speech gesture and its synchronized speech are jointly unpacked.

Iconic Gesture.

A gesture whose form resembles the concrete content it depicts, such as tracing a path or miming an action.

Illustrator.

Ekman and Friesen's term for a gesture that accompanies and depicts speech, as distinct from an emblem that can stand alone in place of words.

Kinesics.

The systematic study of body motion — gesture, posture, facial movement, and gaze — as a channel of communication, of which gesture is one part.

Metaphoric Gesture.

A gesture that gives an abstract idea a spatial or physical vehicle, as when the hand presents a concept as an object held out.

Representational Action.

Novack and Goldin-Meadow's term for schematized action that is stripped of direct effect on the world and so comes to represent rather than to do.

Key Researchers

Martha W. Alibali

. Professor of psychology at the University of Wisconsin–Madison; her work on gesture, mathematical cognition, and learning includes the gesture-for-conceptualization and gesture-as-simulated-action frameworks. Wikipedia - Google Scholar - Faculty Page

David Efron

(1904-1981). Argentine-American scholar whose Gesture and Environment (1941) founded the cross-cultural study of gesture, showing that gestural style is shaped by culture rather than race. Wikipedia - Wikidata

Susan Goldin-Meadow

. Beardsley Ruml Distinguished Service Professor at the University of Chicago; her research established gesture's role in revealing and promoting learning, the speech-gesture mismatch, and homesign. Wikipedia - Faculty Page

Spencer D. Kelly

. Professor of psychological and brain sciences at Colgate University and co-director of its Center for Language and Brain; he studies the bidirectional integration of speech and gesture in comprehension. Faculty Page - Google Scholar

Adam Kendon

(1934-2022). British gesture researcher whose Gesture: Visible Action as Utterance and the Kendon continuum established visible bodily action as an integral part of the utterance. Wikipedia - Wikidata

Sotaro Kita

(b. 1963). Professor of psychology at the University of Warwick; he proposed the gesture-for-conceptualization hypothesis for how producing gesture shapes thinking and speaking. Wikipedia - Wikidata - Google Scholar

David McNeill

(b. 1933). Professor emeritus of psychology at the University of Chicago; his Hand and Mind established co-speech gesture as a window on thought, introduced the four-way gesture classification, and proposed the growth-point theory. Wikipedia - Wikidata

Asli Özyürek

. Professor of multimodal language and communication at Radboud University and group leader at the Max Planck Institute for Psycholinguistics; she studies how gesture and speech integrate in comprehension and across languages. Wikipedia - Faculty Page - Google Scholar

Frequently Asked Questions

What is a gesture?

A gesture is a movement of the body, usually the hands and arms, that carries communicative or representational meaning. Gesture is one channel of kinesics, the broader study of body motion; the study of gesture concerns the expressive actions of the hands and limbs, from pointing and depicting to the beats that mark speech rhythm (McNeill, 1992).

What are the main kinds of gesture?

David McNeill distinguished four: iconic gestures that depict concrete content, metaphoric gestures that give abstractions a spatial form, deictic gestures that point, and beats that mark the rhythm of speech. Adam Kendon arranged related forms on a continuum from spontaneous gesticulation to conventional sign (McNeill, 1992; Kendon, 2004).

Is gesture the same as sign language?

No. Co-speech gesture lacks a stable lexicon and a combinatorial grammar and is understood only together with the speech it accompanies, whereas a sign language is a full language. Kendon's continuum places spontaneous gesture and conventional sign at opposite ends, with speech-dependence falling and conventionalization rising between them (Kendon, 2004).

How are gesture and speech related?

They form a single integrated system. Co-speech gestures are synchronized with speech to within a fraction of a second and arise from a shared idea unit, so a gesture is a complementary expression of the same thought rather than a translation of the words (McNeill, 1992).

Do gestures actually help a listener understand?

Yes, moderately and selectively. Speech and gesture interact in comprehension, and meta-analyses find a reliable but moderate benefit that is largest when the gesture is concrete and adds information the speech does not supply, and smallest for abstract topics (Kelly et al., 2010; Hostetter, 2011; Dargue et al., 2019).

Does gesturing help the person who gestures?

There is good evidence it does. Children often express a new idea in gesture before they can say it, and gesturing during learning makes that learning more durable; on the gesture-for-conceptualization view, moving the hands helps organize spatial and motor information for speaking and thinking (Cook et al., 2008; Kita et al., 2017).

What is a gesture-speech mismatch?

It is a moment when a speaker's hands express different information from the words, as when a child whose speech gives one solution to a problem produces a gesture that conveys another. Such mismatches often mark a learner who is holding more than one idea and is ready to change (Goldin-Meadow & Alibali, 2013).

Is gesture universal or cultural?

Both, in different respects. The impulse to gesture while speaking is near-universal, but the specific forms, especially emblems and conventional gestures, are culturally learned, as David Efron first demonstrated by showing that gestural style follows culture and assimilation rather than ancestry (Efron, 1941).

References