Experimental setup.

<p>(a) different congruency conditions (instructed participant direction×stimulus direction). (b) Illustration of the two visual tracking conditions and the control condition (horizontal stimulus motion depicted).</p

Measures of coordination.

<p>Mean cross-spectral coherence between (a) instructed and stimulus, (b) non-instructed and stimulus and (c) participants' instructed and non-instructed movements as a function of tracking and congruency.</p

Example movement time series.

<p>Both example time-series exemplify the typical instructed and non-instructed movements of a single participant for a (a) congruent and (b) incongruent trial. For both (a) and (b), the instructed movement was performed in the horizontal (i.e., frontal) dimension. The black line on the right panel reflects the principle eigenvector (<i>v</i>₁) calculated using PCA (see text for more details). Even though the two examples shown in the figure have the same angular direction of deviation, both angular directions were observed in the pool of participants. Furthermore, nearly every participant exhibited some degree of angular deviation in all congruent trials.</p