Fig. 5: Oscillations in bias towards the mean orientation.

a Illustration of how responses were scored, positive if towards the mean orientation in each quadrant. b The black line shows the time course of the bias towards mean orientation of aggregate data, smoothed over 400 trials. The gray area around the line represents ±1 SE computed by bootstrap resampling (1000 reiterations). The colored curve depicts a 7.2 Hz corresponding to the peak spectral amplitude of the combined horizontal and vertical data. c GML spectral analysis of the aggregate data, where each trial bias contributed at the exact delay from the saccadic onset. The amplitude spectrum shows a peak around 7.2 Hz. The gray region shows the 95% confidence limits of the permutation analysis of the bias, keeping trial saccadic onset delay unaltered. d 2D vectors of the peak sinusoidal wave at 9.4 Hz for each individual participant for horizontal (blue dots) and vertical (yellow dots) saccades. The blue and yellow arrows show the mean vector of horizontal and vertical saccades, respectively. The length and direction of the arrows indicate the amplitude and phase (relative to time of saccadic onset). e The average bias from trials within a 25-ms time window around the peaks and troughs of the 9.4 Hz sinusoid wave for horizontal and vertical saccades. f The average bias from trials within a 25-ms time window around the peaks and troughs of the 9.4 Hz sinusoid for each test orientation. In (e, f), the horizontal line within each violin represents the mean bias, and individual data points are overlaid as dots.