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1.
Ann N Y Acad Sci ; 2020 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-33336809

RESUMO

It is commonly understood that hand gesture and speech coordination in humans is culturally and cognitively acquired, rather than having a biological basis. Recently, however, the biomechanical physical coupling of arm movements to speech vocalization has been studied in steady-state vocalization and monosyllabic utterances, where forces produced during gesturing are transferred onto the tensioned body, leading to changes in respiratory-related activity and thereby affecting vocalization F0 and intensity. In the current experiment (n = 37), we extend this previous line of work to show that gesture-speech physics also impacts fluent speech. Compared with nonmovement, participants who are producing fluent self-formulated speech while rhythmically moving their limbs demonstrate heightened F0 and amplitude envelope, and such effects are more pronounced for higher-impulse arm versus lower-impulse wrist movement. We replicate that acoustic peaks arise especially during moments of peak impulse (i.e., the beat) of the movement, namely around deceleration phases of the movement. Finally, higher deceleration rates of higher-mass arm movements were related to higher peaks in acoustics. These results confirm a role for physical impulses of gesture affecting the speech system. We discuss the implications of gesture-speech physics for understanding of the emergence of communicative gesture, both ontogenetically and phylogenetically.

2.
J Acoust Soc Am ; 148(3): 1231, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33003900

RESUMO

Expressive moments in communicative hand gestures often align with emphatic stress in speech. It has recently been found that acoustic markers of emphatic stress arise naturally during steady-state phonation when upper-limb movements impart physical impulses on the body, most likely affecting acoustics via respiratory activity. In this confirmatory study, participants (N = 29) repeatedly uttered consonant-vowel (/pa/) mono-syllables while moving in particular phase relations with speech, or not moving the upper limbs. This study shows that respiration-related activity is affected by (especially high-impulse) gesturing when vocalizations occur near peaks in physical impulse. This study further shows that gesture-induced moments of bodily impulses increase the amplitude envelope of speech, while not similarly affecting the Fundamental Frequency (F0). Finally, tight relations between respiration-related activity and vocalization were observed, even in the absence of movement, but even more so when upper-limb movement is present. The current findings expand a developing line of research showing that speech is modulated by functional biomechanical linkages between hand gestures and the respiratory system. This identification of gesture-speech biomechanics promises to provide an alternative phylogenetic, ontogenetic, and mechanistic explanatory route of why communicative upper limb movements co-occur with speech in humans.

4.
Proc Natl Acad Sci U S A ; 117(21): 11364-11367, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393618

RESUMO

We show that the human voice has complex acoustic qualities that are directly coupled to peripheral musculoskeletal tensioning of the body, such as subtle wrist movements. In this study, human vocalizers produced a steady-state vocalization while rhythmically moving the wrist or the arm at different tempos. Although listeners could only hear and not see the vocalizer, they were able to completely synchronize their own rhythmic wrist or arm movement with the movement of the vocalizer which they perceived in the voice acoustics. This study corroborates recent evidence suggesting that the human voice is constrained by bodily tensioning affecting the respiratory-vocal system. The current results show that the human voice contains a bodily imprint that is directly informative for the interpersonal perception of another's dynamic physical states.


Assuntos
Extremidade Superior/fisiologia , Voz/fisiologia , Adulto , Percepção Auditiva , Feminino , Audição/fisiologia , Humanos , Masculino , Atividade Motora/fisiologia , Experimentação Humana não Terapêutica , Punho/fisiologia
5.
J Mot Behav ; : 1-22, 2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32208833

RESUMO

We investigated the patterns of coordination between the left and right legs that support the task of maintaining an upright standing posture. We used cross-wavelet analyses to assess coordination between the centers of pressure under the left and right feet. We recruited participants with a lateralized functional preference for their right leg, and we manipulated whether these participants stood with symmetric/asymmetric stances and whether their eyes were open or closed. Our hypotheses were derived from the Haken-Kelso-Bunz (HKB) model of interlimb coordination dynamics. Consistent with HKB model predictions, we observed (1) coordination taking the form of metastable, transient epochs of stable phase relations, (2) preferences for in-phase and anti-phase coordination patterns, and (3) changes in pattern stability and phase leads associated with both stance asymmetry and right-side lateral preference. The form and stability of observed coordination patterns were mediated by the availability of visual information. Our findings confirm the existence of a metastable coordination dynamic associated with the task of maintaining upright stance. We discuss the implications of these findings in the context of evaluating the utility of the HKB model for understanding the functional organization of the posture system.

6.
Exp Brain Res ; 238(4): 917-930, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32172353

RESUMO

Navigation can be haptically guided. In specific, tissue deformations arising from both limb motions during locomotion (i.e., gait patterns) and mechanical interactions between the limbs and the environment can convey information, detected by the haptic perceptual system, about how the body is moving relative to the environment. Here, we test hypotheses concerning the properties of mechanically contacted environments relevant to navigation of this kind. We studied blindfolded participants implicitly learning to perceive their location within environments that were physically encountered via walking on, stepping on, and probing ground surfaces with a cane. Environments were straight-line paths with elevated sections where the path either narrowed or remained the same width. We formed hypotheses concerning how these two environments would affect spatial updating and reorientation processes. In the constant pathwidth environment, homing task accuracy was higher and a manipulation of the elevated surface, to be either unchanged or (unbeknown to participants) shortened, biased the performance. This was consistent with our hypothesis of a metric recalibration scaled to elevated surface extent. In the narrowing pathwidth environment, elevated surface shortening did not bias performance. This supported our hypothesis of positional recalibration resulting from contact with the leading edge of the elevated surface. We discuss why certain environmental properties, such as path-narrowing, have significance for how one becomes implicitly oriented the surrounding environment.

7.
J Exp Psychol Gen ; 149(2): 391-404, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31368760

RESUMO

The phenomenon of gesture-speech synchrony involves tight coupling of prosodic contrasts in gesture movement (e.g., peak velocity) and speech (e.g., peaks in fundamental frequency; F0). Gesture-speech synchrony has been understood as completely governed by sophisticated neural-cognitive mechanisms. However, gesture-speech synchrony may have its original basis in the resonating forces that travel through the body. In the current preregistered study, movements with high physical impact affected phonation in line with gesture-speech synchrony as observed in natural contexts. Rhythmic beating of the arms entrained phonation acoustics (F0 and the amplitude envelope). Such effects were absent for a condition with low-impetus movements (wrist movements) and a condition without movement. Further, movement-phonation synchrony was more pronounced when participants were standing as opposed to sitting, indicating a mediating role for postural stability. We conclude that gesture-speech synchrony has a biomechanical basis, which will have implications for our cognitive, ontogenetic, and phylogenetic understanding of multimodal language. (PsycINFO Database Record (c) 2020 APA, all rights reserved).


Assuntos
Gestos , Fala/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Masculino , Física , Adulto Jovem
8.
Neuroscience ; 392: 203-218, 2018 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-29958941

RESUMO

Rhythmic actions are characterizable as a repeating invariant pattern of movement together with variability taking the form of cycle-to-cycle fluctuations. Variability in behavioral measures is atypically random, and often exhibits serial temporal dependencies and statistical self-similarity in the scaling of variability magnitudes across timescales. Self-similar (i.e. fractal) variability scaling is evident in measures of both brain and behavior. Variability scaling structure can be quantified via the scaling exponent (α) from detrended fluctuation analysis (DFA). Here we study the task of coordinating thumb-finger tapping to the beats of constructed auditory stimuli. We test the hypothesis that variability scaling evident in tap-to-tap intervals as well as in the fluctuations of cortical hemodynamics will become entrained to (i.e. drawn toward) manipulated changes in the variability scaling of a stimulus's beat-to-beat intervals. Consistent with this hypothesis, manipulated changes of the exponent α of the experimental stimuli produced corresponding changes in the exponent α of both tap-to-tap intervals and cortical hemodynamics. The changes in hemodynamics were observed in both motor and sensorimotor cortical areas in the contralateral hemisphere. These results were observed only for the longer timescales of the detrended fluctuation analysis used to measure the exponent α. These findings suggest that complex auditory stimuli engage both brain and behavior at the level of variability scaling structures.


Assuntos
Percepção Auditiva/fisiologia , Movimento , Desempenho Psicomotor , Córtex Sensório-Motor/fisiologia , Estimulação Acústica , Adulto , Mapeamento Encefálico , Feminino , Dedos , Humanos , Masculino , Atividade Motora , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
9.
Front Psychol ; 8: 1061, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28701975

RESUMO

Humans commonly engage in tasks that require or are made more efficient by coordinating with other humans. In this paper we introduce a task dynamics approach for modeling multi-agent interaction and decision making in a pick and place task where an agent must move an object from one location to another and decide whether to act alone or with a partner. Our aims were to identify and model (1) the affordance related dynamics that define an actor's choice to move an object alone or to pass it to their co-actor and (2) the trajectory dynamics of an actor's hand movements when moving to grasp, relocate, or pass the object. Using a virtual reality pick and place task, we demonstrate that both the decision to pass or not pass an object and the movement trajectories of the participants can be characterized in terms of a behavioral dynamics model. Simulations suggest that the proposed behavioral dynamics model exhibits features observed in human participants including hysteresis in decision making, non-straight line trajectories, and non-constant velocity profiles. The proposed model highlights how the same low-dimensional behavioral dynamics can operate to constrain multiple (and often nested) levels of human activity and suggests that knowledge of what, when, where and how to move or act during pick and place behavior may be defined by these low dimensional task dynamics and, thus, can emerge spontaneously and in real-time with little a priori planning.

10.
Nonlinear Dynamics Psychol Life Sci ; 19(4): 345-94, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26375932

RESUMO

Dexterous action, as conceptualized by Bernstein in his influential ecological analysis of human behavior, is revealed in the ability to flexibly generate behaviors that are adaptively tailored to the demands of the context in which they are embedded. Conceived as complex adaptive behavior, dexterity depends upon the qualities of robustness and degeneracy, and is supported by the functional complexity of the agent-environment system. Using Bernstein's and Gibson's ecological analyses of behavior situated in natural environments as conceptual touchstones, we consider the hypothesis that complex adaptive behavior capitalizes upon general principles of self-organization. Here, we outline a perspective in which the complex interactivity of nervous-system, body, and environment is revealed as an essential resource for adaptive behavior. From this perspective, we consider the implications for interpreting the functionality and dysfunctionality of human behavior. This paper demonstrates that, optimal variability, the topic of this special issue, is a logical consequence of interpreting the functionality of human behavior as complex adaptive behavior.


Assuntos
Adaptação Psicológica/fisiologia , Atividade Motora/fisiologia , Fenômenos Biomecânicos , Meio Ambiente , Humanos , Dinâmica não Linear
11.
J Exp Psychol Hum Percept Perform ; 41(3): 665-79, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25751036

RESUMO

Understanding stable patterns of interpersonal movement coordination is essential to understanding successful social interaction and activity (i.e., joint action). Previous research investigating such coordination has primarily focused on the synchronization of simple rhythmic movements (e.g., finger/forearm oscillations or pendulum swinging). Very few studies, however, have explored the stable patterns of coordination that emerge during task-directed complementary coordination tasks. Thus, the aim of the current study was to investigate and model the behavioral dynamics of a complementary collision-avoidance task. Participant pairs performed a repetitive targeting task in which they moved computer stimuli back and forth between sets of target locations without colliding into each other. The results revealed that pairs quickly converged onto a stable, asymmetric pattern of movement coordination that reflected differential control across participants, with 1 participant adopting a more straight-line movement trajectory between targets, and the other participant adopting a more elliptical trajectory between targets. This asymmetric movement pattern was also characterized by a phase lag between participants and was essential to task success. Coupling directionality analysis and dynamical modeling revealed that this dynamic regime was due to participant-specific differences in the coupling functions that defined the task-dynamics of participant pairs. Collectively, the current findings provide evidence that the dynamical coordination processes previously identified to underlie simple motor synchronization can also support more complex, goal-directed, joint action behavior, and can participate the spontaneous emergence of complementary joint action roles.


Assuntos
Desempenho Psicomotor , Comportamento Social , Humanos , Relações Interpessoais , Modelos Psicológicos , Percepção de Movimento , Análise e Desempenho de Tarefas
12.
Exp Brain Res ; 231(4): 383-96, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24162860

RESUMO

"Quiet standing" is standing without intended movement. To the naked eye, a person "quiet standing" on a rigid surface of support is stationary. In the laboratory quiet standing is indexed by behavior (at the millimeter scale) of the center of pressure (COP), the point location of the vertical ground reaction force vector (GRF). We asked whether quiet standing is lateralized and whether the COP dynamics of the right and left legs differ. In answer, we reexamined a previous quiet standing experiment (Kinsella-Shaw et al. in J Mot Behav 38:251-264, 2006) that used dual, side-by-side, force plates to investigate effects of age and embedding environment. All participants, old (M age = 72.2 ± 4.90 years) and young (M age = 22.8 ± 0.83 years), were right handed and right footed. Cross-recurrence quantification of the anterior-posterior and mediolateral coordinates of each COP revealed that, independent of age, and with no right GRF bias, right-leg coordination was (1) more dynamically stable and less noisy than left-leg coordination and (2) more responsive to changes in degree of visible structure. The results are considered in the context of theories of laterality inclusive of lateralized differences in postural dynamics.


Assuntos
Envelhecimento/fisiologia , Lateralidade Funcional/fisiologia , Equilíbrio Postural/fisiologia , Adulto , Fatores Etários , Idoso , Fenômenos Biomecânicos/fisiologia , Feminino , Humanos , Perna (Membro)/fisiologia , Masculino , Modelos Teóricos , Postura/fisiologia , Adulto Jovem
13.
J Mot Behav ; 45(3): 239-47, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23663188

RESUMO

Given the flexible organization of locomotion evidenced in the many ways the limbs can be coordinated, the authors explored the potentially correspondingly flexible organization of nonvisual (kinesthetic) distance perception. As kinesthetic distance perception is known to be affected by how the limbs are coordinated, the authors probed the potential perceptual contribution of the arms during locomotion by manipulating arm-leg coordination patterns in blind-walked distance-matching tasks. Whereas manipulation of arm-leg coordination for walking with free-swinging arms had no observable perceptual consequences, comparable manipulation for walking with hiking poles did affect distance matching. These results suggest that under conditions in which the arms act to propel the body (e.g., crawling or stair-climbing) a person's nonvisual sense of movement is conveyed in the coordinated actions of all four limbs.


Assuntos
Braço/fisiologia , Percepção de Distância/fisiologia , Cinestesia/fisiologia , Locomoção/fisiologia , Desempenho Psicomotor/fisiologia , Caminhada/fisiologia , Adulto , Fenômenos Biomecânicos/fisiologia , Humanos
14.
Exp Brain Res ; 221(3): 351-5, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23030020

RESUMO

The current study examined whether the amount and location of available movement information influenced the stability of visuomotor coordination. Participants coordinated a handheld pendulum with an oscillating visual stimulus in an inphase and antiphase manner. The effects of occluding different amounts of phase at different phase locations were examined. Occluding the 0°/180° phase locations (end-points) significantly increased the variability of the visuomotor coordination. The amount of occlusion had little or no affect on the stability of the coordination. We concluded that the end-points of a visual rhythm are privileged and provide access to movement information that ensures stable coordination. The results are discussed with respect to the proposal of Bingham (Ecol Psychol 16:45­43, 2004) and Wilson et al. (Exp Brain Res 165:351­361, 2005) that the relevant information for rhythmic visual coordination is relative direction information.

15.
Tech Hand Up Extrem Surg ; 16(2): 91-4, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22627934

RESUMO

Scaphoid nonunions are challenging cases that first must be identified and then treated based on stability, collapse, and vascularity. Unstable nonunions are identified on the basis of collapse of the scaphoid into the "humpback" deformity with an increased intrascaphoid and scapholunate angles. The importance of restoring normal scaphoid alignment has been stressed, because failure to do so leads to worse clinical and radiographic results with predictable patterns of radiocarpal arthrosis. We present a technique to correct unstable scaphoid nonunions using a single volar-based incision with harvesting of volar distal radius corticocancellous autograft. This technique allows the avoidance of harvest site morbidity and has union rates comparable with the gold standard of iliac crest.


Assuntos
Fraturas não Consolidadas/cirurgia , Deformidades Adquiridas da Mão/cirurgia , Rádio (Anatomia)/transplante , Osso Escafoide , Transplante Ósseo/efeitos adversos , Transplante Ósseo/métodos , Transplante Ósseo/reabilitação , Deformidades Adquiridas da Mão/etiologia , Humanos , Osso Escafoide/lesões , Osso Escafoide/cirurgia , Coleta de Tecidos e Órgãos/métodos , Transplante Autólogo
16.
J Exp Psychol Hum Percept Perform ; 38(4): 1014-25, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22506786

RESUMO

Bipedal gaits have been classified on the basis of the group symmetry of the minimal network of identical differential equations (alias cells) required to model them. Primary gaits are characterized by dihedral symmetry, whereas secondary gaits are characterized by a lower, cyclic symmetry. This fact was used in a test of human odometry. Results suggest that when distance is measured and reported by gaits from the same symmetry class, primary and secondary gaits are comparable. Switching symmetry classes at report compresses (primary to secondary) or inflates (secondary to primary) measured distance, with the compression and inflation equal in magnitude. Lessons are drawn from modeling the dynamics of behaviors executed in parallel (e.g., interlimb coordination) to model the dynamics of human odometry, in which the behaviors are executed sequentially. The major observations are characterized in terms of a dynamics of sequentially coupled measure and report phases, with relative velocity as an order parameter, or equilibrium state, and difference in symmetry class as an imperfection parameter, or detuning, of that dynamic.


Assuntos
Fenômenos Biomecânicos/fisiologia , Marcha/fisiologia , Locomoção/fisiologia , Adulto , Humanos , Modelos Psicológicos , Testes Neuropsicológicos , Percepção Espacial/fisiologia , Adulto Jovem
17.
J Mot Behav ; 43(4): 285-94, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21774605

RESUMO

The authors reexamined reported effects of age, illumination, and stationary visible structure on the net center of pressure (COP) derived from dual, side-by-side force plates (J. Kinsella-Shaw, S. Harrison, C. Colon-Semenza, & M. Turvey, 2006 ) from the perspective of axial postural control. They questioned how left and right COP(x)(t), COP(y)(t), and vertically oriented ground reactive force, GRF(z)(t), coordinated during quiet standing. The Cross-recurrence Quantification (CRQ) revealed that coordination was primarily between fluctuations of similar direction, with coordination of left and right COP(y) (t) (anteroposterior fluctuations) dominant. CRQ also revealed that (a) illumination and structure affected the interlimb dynamics of older (M age = 72.2 ± 4.90 years) participants more than their younger (M age = 22.8 ± 0.83 years) counterparts, and (b) older participants exhibited greater interlimb entrainment (dynamical stability) in the presence of greater interlimb noise.


Assuntos
Envelhecimento/fisiologia , Meio Ambiente , Perna (Membro)/fisiologia , Equilíbrio Postural/fisiologia , Percepção Visual/fisiologia , Adulto , Idoso , Feminino , Humanos , Masculino , Fenômenos Fisiológicos Musculoesqueléticos , Estimulação Luminosa , Percepção Espacial
18.
J Exp Psychol Hum Percept Perform ; 37(1): 193-206, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21077721

RESUMO

At issue in the present series of experiments was the ability to prospectively perceive the action-relevant properties of hand-held tools by means of dynamic touch. In Experiment 1, participants judged object move-ability. In Experiment 2, participants judged how difficult an object would be to hold if held horizontally, and in Experiments 3 and 4, participants rated how fast objects could be rotated. In each experiment, the first and second moments of mass distribution of the objects were systematically varied. Manipulations of wielding speed and orientation during restricted exploration revealed perception to be constrained by (a) the moments of mass distribution of the hand-tool system, (b) the qualities of exploratory wielding movements, and (c) the intention to perceive each specific property. The results are considered in the context of the ecological theory of dynamic touch. Implications for accounts of the informational basis of dynamic touch and for the development of a theory of haptically perceiving the affordance properties of tools are discussed.


Assuntos
Comportamento Exploratório , Intenção , Percepção do Tato , Humanos , Julgamento , Movimento , Desempenho Psicomotor , Tato
19.
J Exp Biol ; 213(Pt 9): 1436-42, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20400627

RESUMO

For some animals (e.g. the night-active wandering spider) the encounters with the habitat that result in place learning are predominantly mechanical. We asked whether place learning limited to mechanical contact, like place learning in general, entails vectors tied to individual landmarks and relations between landmarks. We constructed minimal environments for blindfolded human participants. Landmarks were raised steps. 'Home' was a mechanically indistinct location. Travel was linear. The mechanical contacts were those of walking, stepping, and probing with a soft-tipped cane. Home-orienting activities preceded tests of finding home from a given location with landmarks unchanged or (unbeknown to participants) shifted. In a one-landmark environment, perceived home shifted in the same direction, with the same magnitude, as the shifted landmark. In an environment of two landmarks located in the same direction from home, shifting the further landmark toward home resulted in a change in home's perceived location that preserved the original ratio of distances separating home, nearer landmark, and further landmark. Both findings were invariant over the travel route to the test location and repetitions of testing. It seems, therefore, that for humans (and, perhaps, for wandering spiders), mechanical contact can reveal the vectors and relations specifying places.


Assuntos
Aprendizagem , Percepção Espacial , Percepção do Tato , Bengala , Feminino , Humanos , Masculino , Caminhada
20.
J Mot Behav ; 42(1): 85-97, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20051351

RESUMO

Upright standing is always environmentally embedded and typically co-occurs with another (suprapostural) activity. In the present study, the authors investigate how these facts affect postural dynamics in an experiment in which younger (M age = 20.23 years, SD = 2.02 years) and older (M age = 75.26 years, SD = 4.87 years) participants performed a task of detecting letters in text or maintaining gaze within a target while standing upright in a structured or nonstructured stationary environment. They extracted the coefficients of drift (indexing attractor strength) and diffusion (indexing noise strength) from the center of pressure (COP) time series in anteroposterior (AP) and mediolateral (ML) axes. COP standard deviation decreased with drift and increased with diffusion. The authors found that structure reduced AP diffusion for both groups and that letter detection reduced younger SDAP (primarily by diffusion decrease) and increased older SDML (primarily by drift decrease). For older and younger participants, ML drift was lower during letter detection. Further, in older letter detection, larger visual contrast sensitivity was associated with larger ML drift and smaller SDML, raising the hypotheses that ML sway helps information detection and reflects neurophysiological age.


Assuntos
Fatores Etários , Meio Ambiente , Postura/fisiologia , Análise e Desempenho de Tarefas , Idoso , Análise de Variância , Atenção , Sensibilidades de Contraste/fisiologia , Fixação Ocular/fisiologia , Humanos , Modelos Biológicos , Equilíbrio Postural/fisiologia , Leitura , Processos Estocásticos , Percepção Visual , Adulto Jovem
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