The sensory feedback mechanisms enabling couples to walk synchronously: An initial investigation

Abstract

The inattentive eye often will not notice it, but synchronization among human walking partners is quite common. In this first investigation of this phenomenon, we studied its frequency and the mechanisms that contribute to this form of "entrainment." Specifically, by modifying the available communication links between two walking partners, we isolated the feedback mechanisms that enable couples to synchronize their stepping pattern when they walk side-by-side. Although subjects were unaware of the research aims and were not specifically asked to walk in synchrony, we observed synchronized walking in almost 50% of the walking trials, among couples who do not usually walk together. The strongest in-phase synchrony occurred in the presence of tactile feedback (i.e., handholding), perhaps because of lower and upper extremity coupling driven in part by arm swing. Interestingly, however, even in the absence of visual or auditory communication, couples also frequently walked in synchrony while 180 degrees out-of-phase, likely using different feedback mechanisms. These findings may partially explain how patients with certain gait disorders and disturbed rhythm enhance their gait when they walk with a partner and suggest alternative interventions that might improve the stepping pattern. Further, this preliminary investigation highlights the relatively ubiquitous nature of an interesting phenomenon that has not previously been studied and suggests that further work is needed to better understand the mechanisms that entrain the gait of two walking partners and allows couples to walk in synchrony with minimal or no conscious effort.

Self in motion: sensorimotor and cognitive mechanisms in gait agency

“…In goal-directed upper limb studies, such dissociations have not been reported and the more participants were required to adjust their movements in order to reach the target, the lower their corresponding agency ratings became (Fourneret et al 2002;Slachevsky et al 2001). As our task did not require participants to adjust their gait, we suggest that the temporal information of the feedback was automatically integrated into forward motor planning, a property of locomotion often employed in neurorehabilitation (rhythmic auditory stimulation; Hayden et al 2009;Thaut et al 1997) and in line with recent studies on side-by-side walkers (Nessler and Gilliland 2009;Zivotofsky and Hausdorff 2007). We argue that the visuospatial incongruence (left-right reversal) in our study may have outweighed the temporal synchrony for gait agency judgments, creating the strong dissociation between agency and gait.…”

Sensorimotor synchronization: A review of recent research (2006–2012)

“…When pairs of women were asked to walk together down a hallway (Zivotofsky & Hausdorff, 2007), tactile information (holding hands) led to synchronization of steps in about 50 % of the cases, whereas manipulations of visual and auditory information had no significant effect. In a similar, more recent study (Zivotofsky, Gruendlinger, & Hausdorff, 2012), half of the pairs tested never synchronized, whereas the other half did so in most conditions.…”

Musical agency reduces perceived exertion during strenuous physical performance

“…Furthermore, it would be interesting to know whether the observed effect is stronger in a group setting (which is ecologically valid for most forms of musical activities) than when performed alone. For example, in a social interaction there may be motorically contagious effects that, for example, are modulated by synchronizing (27)(28)(29). Another point that would be interesting to further address is how a subjective perception of fun may modulate perceived exertion (note that the musical agency condition is likely to have been perceived as more fun/more exciting).…”