Fig. 1.

a The proportion of trials where the participant judged stimulus B as first is plotted for each SOA and the data is fitted to a Psychometric function. Two parameters were left free to vary in the fitting process: µ gives the mean of the fitted curve (0.5 point, referred to as the Point of Subjective Simultaneity; PSS), and β gives the slope, which is a measure of sensitivity and can be used to calculate the Just Noticeable Difference (JND). b Schematic of the experimental set-up for a right handed participant. The participant held a tactor, which was embedded in a foam cube using the thumb and forefinger of their dominant hand. An LED was positioned next to the tactor on the foam cube. The participant was instructed to fixate on a grey cross positioned 19 cm above the speaker