Fig. 2.

a) Dependence of maximum cross correlation, ρ, on delay, τ. The value of ρ represents the highest correlation between participant and target, allowing for an arbitrary phase shift. Note that the negative slope doubles after 400 ms. b) Dependence of phase shift, τ^*, on delay, τ. For τ ≥ 600 ms, phase shifts are most likely artifacts of using Eq. 5 on time series which are not well correlated. c) Dependence of τ^* on τ ≤ 400, highlighting a linear regime