Try out PMC Labs and tell us what you think. Learn More. This fMRI study investigated neural systems that interpret body language—the meaningful emotive expressions conveyed by body movement. Participants watched videos of performers engaged in modern dance or Connecticut body language flirting that conveyed specific themes such as hope, agony, lust, or exhaustion. We tested whether the meaning of an affectively laden performance was decoded in localized brain substrates as a distinct property of action separable from other superficial features, such as choreography, kinematics, performer, and low-level visual stimuli.
A repetition suppression RS procedure was used to identify brain regions that decoded the meaningful affective state of a performer, as evidenced by decreased activity when emotive themes were repeated in successive performances. Because the theme was the only feature repeated across video clips that were otherwise entirely different, the occurrence of RS identified brain substrates that differentially coded the specific meaning of expressive performances.
RS was observed bilaterally, extending anteriorly along middle and superior temporal gyri into temporal pole, medially into insula, rostrally into inferior orbitofrontal cortex, and caudally into hippocampus and amygdala. Behavioral data on a separate task indicated that interpreting themes from modern dance was more difficult than interpreting pantomime; a result that was also reflected in the fMRI data.
There was greater RS in left hemisphere, suggesting that the more abstract metaphors used to express themes in dance compared to pantomime posed a greater challenge to brain substrates directly involved in decoding those themes.
We propose that the meaning-sensitive temporal-orbitofrontal regions observed here comprise a superordinate functional module of a known hierarchical action observation network AONwhich is critical to the construction of meaning from expressive movement. The findings are discussed with respect to a predictive coding model of action understanding. Body language is a powerful form of non-verbal communication providing important clues about the intentions, emotions, and motivations of others. In the course of our everyday lives, we pick up information about what people are thinking and feeling through their body posture, mannerisms, gestures, and the prosody of their movements.
This intuitive social awareness is an impressive feat of neural integration; the cumulative result of activity in distributed brain systems specialized for coding a wide range of social information. Reading body language is more than just a matter of perception. It entails not only recognizing and coding socially relevant visual information, but also ascribing meaning to those representations. We know a great deal about brain systems involved in the perception of facial expressions, eye movements, body movement, hand gestures, and goal directed actions, as well as those mediating affective, decision, and motor responses to social stimuli.
Beyond the decoding of body motion, what are the brain substrates directly involved in extracting meaning from affectively laden body expressions? The brain has several functionally specialized structures and systems for processing socially relevant perceptual information. A subcortical pulvinar-superior Connecticut body language flirting circuit mediates reflex-like perception of emotion from body posture, particularly fear, and activates commensurate reflexive motor responses Dean et al. A region of the occipital cortex known as the extrastriate body area EBA is sensitive to bodily form Bonda et al.
The fusiform gyrus of the ventral occipital and temporal lobes has a critical role in processing faces and facial expressions McCarthy et al.
Posterior superior temporal sulcus is involved in perceiving the motion of biological forms in particular Allison et al. Somatosensory, ventromedial prefrontal, premotor, and insular cortex contribute to one's own embodied awareness of perceived emotional states Adolphs et al. Visuomotor processing in a functional brain network known as the action observation network AON codes observed action in distinct functional modules that together link the perception of action and emotional body language with ongoing behavioral goals and the formation of adaptive reflexes, decisions, and motor behaviors Grafton et al.
Given all we know about how bodies, faces, emotions, and actions are perceived, one might expect a clear consensus on how meaning is derived from these percepts. Perhaps surprisingly, while we know these systems are crucial to integrating perceptual information with affective and motor responses, how the brain deciphers meaning based on body movement remains unknown.
The focus of this investigation was to identify brain substrates that decode meaning from body movement, as evidenced by meaning-specific neural processing that differentiates body movements conveying distinct expressions.
To identify brain substrates sensitive to the meaningful emotive state of an actor conveyed through body movement, we used repetition suppression RS fMRI. This technique identifies regions of the brain that code for a particular stimulus dimension e. When a particular attribute is repeated, synaptic activity and the associated blood oxygen level-dependent BOLD response decreases in voxels containing neuronal assemblies that code that attribute Wiggs and Martin, ; Grill-Spector and Malach, We have used this method ly to show that various properties of an action such as movement kinematics, object goal, outcome, and context-appropriateness of action mechanics are uniquely coded by different neural substrates within a parietal-frontal action observation network AON; Hamilton and Grafton, ; Ortigue et al.
Here, we applied RS-fMRI to identify brain areas in which activity decreased when the meaningful emotive theme of an expressive performance was repeated between trials. The demonstrate a novel coding function of the AON—decoding meaning from body language.
Body language in the brain: constructing meaning from expressive movement
Working with a group of professional dancers, we produced a set of video clips in which performers intentionally expressed a particular meaningful theme either through dance or pantomime. Typical themes consisted of expressions of hope, agony, lust, or exhaustion. The experimental manipulation of theme was studied independently of choreography, performer, or camera viewpoint, which allowed us to repeat the meaning of a movement sequence from one trial to another while varying physical movement characteristics and perceptual features. Manipulating trial sequence to induce RS in brain regions that decode body language.
The order of video presentation was controlled such that themes depicted in consecutive videos were either novel or repeated. Each consecutive video clip was unique; repeated themes were always portrayed by different dancers, different camera angles, or both. Thus, RS for repeated themes was not the result of low-level visual features, but rather identified brain areas that were sensitive to the specific meaningful theme conveyed by a performance. In brain regions showing RS, a particular affective theme—hope, for example—will evoke Connecticut body language flirting particular pattern of neural activity.
A novel theme on the subsequent trial—illness, for instance—will trigger a different but equally strong pattern of neural activity in distinct cell assemblies, resulting in an equivalent BOLD response.
In contrast, a repetition of the hopefulness theme on the subsequent trial will trigger activity in the same neural assemblies as the first trial, but to a lesser extent, resulting in a reduced BOLD response for repeated themes. In this way, regions showing RS reveal regions that support distinct patterns of neural activity in response to different themes. Participants were scanned using fMRI while viewing a series of s video clips depicting modern dance or pantomime performances that conveyed specific meaningful themes.
Because each performer had a unique artistic style, the same theme could be portrayed using completely different physical movements. This allowed the repetition of meaning while all other aspects of the physical stimuli varied from trial to trial. We predicted that specific regions of the AON engaged by observing expressive whole body movement would show suppressed BOLD activation for repeated relative to novel themes RS. Brain regions showing RS would reveal brain substrates directly involved in decoding meaning based on body movement. The dance and pantomime performances used here conveyed expressive themes through movement, but did not rely on typified, canonical facial expressions to invoke particular affective responses.
Body language basics
Rather, meaningful themes were expressed with unique artistic choreography while facial expressions were concealed with a classic white mime's mask. The result was a subtle stimulus set that promoted thoughtful, interpretive viewing that could not elicit reflex-like responses based on prototypical facial expressions.
In so doing, the present study shifted the focus away from automatic affective resonance toward a more deliberate ascertainment of meaning from movement. While dance and pantomime both expressed meaningful emotive themes, the quality of movement and the types of gestures used were different.
Little-known facts about body language
Pantomime sequences used fairly mundane gestures and natural, everyday movements. Dance sequences used stylized gestures and interpretive, prosodic movements. The critical distinction between these two types of expressive movement is in the degree of abstraction in the metaphors that link movement with meaning see Morris, for a detailed discussion of movement metaphors. Pantomime by definition uses gesture to mimic everyday objects, situations, and behavior, and thus relies on relatively concrete movement metaphors.
Body language: examples and 5 little-known facts
In contrast, dance relies on more abstract movement metaphors that draw on indirect associations between qualities of movement and the emotions and thoughts it evokes in a viewer. We predicted that since dance expresses meaning more abstractly than pantomime, dance sequences would be more difficult to interpret than pantomimed sequences, and would likewise pose a greater challenge to brain processes involved in decoding meaning from movement.
Thus, we predicted greater involvement of thematic decoding areas for danced than for pantomimed movement expressions. Greater RS for dance than pantomime could result from dance triggering greater activity upon a first presentation, a greater reduction in activity with a repeated presentation, or some combination of both.
Given our prediction that greater RS for dance would be linked to interpretive difficulty, we hypothesized it would be manifested as an increased processing demand resulting in greater initial BOLD activity for novel danced themes. Performers also agreed in writing to allow the use of their images and videos for scientific purposes.
Eight themes were depicted, including four danced themes happy, hopeful, fearful, and in agony and four pantomimed themes in love, relaxed, ill, and exhausted. Performers wore expressionless white masks so body language was conveyed though gestural whole-body movement as opposed to facial expressions.
To express each theme, performers adopted an affective stance and improvised a short sequence of modern dance choreography two themes per performer or pantomime gestures two themes per performer. Each of the eight themes were performed by two different dancers and recorded from two different camera angles, resulting in four distinct videos representing each theme 32 distinct videos in total; clips available in Supplementary Materials online.
The interpretation task was carried out in a separate session to avoid confounding movement observation in the scanner with explicit decision-making and overt motor responses. Participants were asked to view each video clip and choose from a list of four options the theme that best corresponded with the movement sequence they had just watched.
Responses were made by pressing one of four corresponding buttons on a keyboard. Two behavioral measures were collected to assess how well participants interpreted the intended meaning of expressive performances. Consistency scores reflected the proportion of observers' interpretations that matched the performer's intended expression. Response times indicated the time taken to make interpretive judgments. In order to encourage subjects to use their initial impressions and to avoid over-deliberating, the four response options were previewed briefly immediately prior to video presentation.
Experimental testing procedure. Participants completed a thematic interpretation task outside the scanner, either before or after the imaging session.
Performance on this task allowed us to test whether there was a difference in how readily observers interpreted the intended meaning conveyed through dance or pantomime. Any performance differences on this explicit theme judgment task could help interpret the functional ificance of observed differences in brain activity associated with passively viewing the two types of movement in the scanner. For the interpretation task collected outside the scanner, videos were presented and responses collected on a Mac Powerbook G4 laptop programmed using the Psychtoolbox v.
This list remained on the screen for 3 s, the screen blanked for ms, and then the movie played for 10 s. Following the presentation of the movie, the four response options were presented again, and remained on the screen until a response was made.
Each unique video was presented twice, resulting in 64 trials total. Video order was randomized for each participant, and the response options for each trial included the intended theme and three randomly selected alternatives. Each volume consisted of 37 slices acquired parallel to the AC—PC plane interleaved acquisition; 3 mm thick with 0.
Each participant completed four functional scanning runs lasting approximately 7. While there were a total of eight themes in the stimulus set for the study, each scanning run depicted only two of those eight themes. Over the course of all four scanning runs, all eight themes were depicted. Trial sequences were arranged such that theme of a movement sequence was either novel or repeated with respect to the trial. Novel and repeated themes were intermixed within each scanning run, with no more than three sequential repetitions of the same theme.