TABLE 1.

Equations Relating Torque to Force in Exp. 3

Experimental condition	Torque/Force relation
Constant torque	τ = 0.20 Nm
Positive correlation (1)	τ = f * L
Negative correlation (1,3)	τ = τ0 – f * L
Uncorrelated (2,3)	$\tau =\{\begin{array}{cc}\hfill f\ast L^{\prime },& \hfill p=0.5\hfill \\ \hfill {{\tau }^{\prime }}_0-f\ast L^{\prime },& \hfill p=0.5\hfill \end{array}\phantom{\}}$

⁽¹⁾L = 0.05 m;

⁽²⁾L’: randomly selected between 0.00 m and 0.05 m;

⁽³⁾τ₀ & τ’₀ : selected for each trial to center the distribution of torque around 0.2 Nm;

In all conditions, the stiffness of the reference spring was 500 N/m.