Traces across the body: influence of music-dance synchrony on the observation of dance

Abstract

In previous studies investigating entrainment and person perception, synchronized movements were found to enhance memory for incidental person attributes. Although this effect is robust, including in dance, the process by which it is actuated are less well understood. In this study, two hypotheses are investigated: that enhanced memory for person attributes is the result of (1) increased gaze time between in-tempo dancers; and/or (2) greater attentional focus between in-tempo dancers. To explore these possible mechanisms in the context of observing dance, an eye-tracking study was conducted in which subjects watched videos of pairs of laterally positioned dancers; only one of the dancers was synchronized with the music, the other being asynchronous. The results were consistent with the first hypothesis-music-dance synchrony gives rise to increased visual inspection times. In addition, there was a preference for upper-body fixations over lower-body fixations across both synchronous and asynchronous conditions. A subsequent, single-dancer eye-tracking study investigated fixations across different body regions, including head, torso, legs and feet. Significantly greater dwell times were recorded for head than torso and legs; feet attracted significantly less dwell time than any other body region. Lastly, the study sought to identify dance gestures responsible for torso- and head-directed fixations. Specifically we asked whether there are features in dance that are specially designed to direct an observer's gaze towards the face-the main "communicative portal" with respect to the transmission of intent, affect and empathy.

Keywords: entrainment; eye movements; music and dance; person perception; synchronization.

Figure 1

Notched boxplot of mean dwell times per Music-Dance level: MM (medium music-medium dance); SS (slow music-slow dance); MS (medium music-slow dance); SM (slow music-medium dance); NM (no music-medium dance); NS (no music-slow dance). Synchronous levels are indicated in light gray, asynchronous in dark gray, and no-music levels in white. Notches extend to +/−1.58 IQR/sqrt(n). If two boxes’ notches do not overlap, there is “strong evidence” that their medians differ at roughly a 95% confidence interval (Chambers et al., ; p. 62).

Figure 2

Mean saccade lengths per Music-Dance level.

Figure 3

Left panel: mean dwell times for the head, torso, legs and feet of the dancer. Right panel: corresponding ROIs.

Figure 4

Top: graph showing mean fixation-position SDs for each 500 ms time window for the middle 20-s of the slow-dance video (seconds 20–40). Bottom: Still-frames (A), (B), (C) and (D) correspond to the transparent, light-gray vertical bars in the graph above. The blue, green and red ellipses correspond to levels SS, NS and FS, and show the relative sizes of the mean fixation-position SDs and fixation locations at each point in the video.

Figure 5

Scatterplot of fixation-centroid height against mean fixation-position SD per 500 ms time window for videos in which the dancing is fast. Three levels are present within the plot: fast music-fast dance (FF), slow music-fast dance (SF) and no music-fast dance (NF).

Figure 6

Scatterplot of fixation-centroid height against mean fixation-position SD per 500 ms time window for videos in which the dancing is slow. Three levels are present within the plot: slow music-slow dance (SS), fast music-slow dance (FS) and no music-slow dance (NS).