C3Files

Matlab Struct array of data for subject C3. Contains raweyedata which is of the form [time pupilrecognition xposition(pix) yposition(pix)] , xdat which is the value associated with the image and trial which gives the trial letter for the given data

Y7Files

Matlab Struct array of data for subject Y7. Contains raweyedata which is of the form [time pupilrecognition xposition(pix) yposition(pix)] , xdat which is the value associated with the image and trial which gives the trial letter for the given data

FTD5Files

Matlab Struct array of data for subject FTD5. Contains raweyedata which is of the form [time pupilrecognition xposition(pix) yposition(pix)] , xdat which is the value associated with the image and trial which gives the trial letter for the given data

Relationship between Fractal Dimension and Spectral Scaling Decay Rate in Computer-Generated Fractals

Two measures are commonly used to describe scale-invariant complexity in images: fractal dimension (D) and power spectrum decay rate (β). Although a relationship between these measures has been derived mathematically, empirical validation across measurements is lacking. Here, we determine the relationship between D and β for 1- and 2-dimensional fractals. We find that for 1-dimensional fractals, measurements of D and β obey the derived relationship. Similarly, in 2-dimensional fractals, measurements along any straight-line path across the fractal’s surface obey the mathematically derived relationship. However, the standard approach of vision researchers is to measure β of the surface after 2-dimensional Fourier decomposition rather than along a straight-line path. This surface technique provides measurements of β that do not obey the mathematically derived relationship with D. Instead, this method produces values of β that imply that the fractal’s surface is much smoother than the measurements along the straight lines indicate. To facilitate communication across disciplines, we provide empirically derived equations for relating each measure of β to D. Finally, we discuss implications for future research on topics including stress reduction and the perception of motion in the context of a generalized equation relating β to D

FTD2Files

Matlab Struct array of data for subject FTD2. Contains raweyedata which is of the form [time pupilrecognition xposition(pix) yposition(pix)] , xdat which is the value associated with the image and trial which gives the trial letter for the given data

Data from: Temporal structure of human gaze dynamics is invariant during free viewing

We investigate the dynamic structure of human gaze and present an experimental study of the frequency components of the change in gaze position over time during free viewing of computer-generated fractal images. We show that changes in gaze position are scale-invariant in time with statistical properties that are characteristic of a random walk process. We quantify and track changes in the temporal structure using a well-defined scaling parameter called the Hurst exponent, H. We find H is robust regardless of the spatial complexity generated by the fractal images. In addition, we find the Hurst exponent is invariant across all participants, including those with distinct changes to higher order visual processes due to neural degeneration. The value we find for H of 0.57 shows that the gaze dynamics during free viewing of fractal images are consistent with a random walk process with persistent movements. Our research suggests the human visual system may have a common strategy that drives the dynamics of human gaze during exploration

Data from: Temporal structure of human gaze dynamics is invariant during free viewing

We investigate the dynamic structure of human gaze and present an experimental study of the frequency components of the change in gaze position over time during free viewing of computer-generated fractal images. We show that changes in gaze position are scale-invariant in time with statistical properties that are characteristic of a random walk process. We quantify and track changes in the temporal structure using a well-defined scaling parameter called the Hurst exponent, H. We find H is robust regardless of the spatial complexity generated by the fractal images. In addition, we find the Hurst exponent is invariant across all participants, including those with distinct changes to higher order visual processes due to neural degeneration. The value we find for H of 0.57 shows that the gaze dynamics during free viewing of fractal images are consistent with a random walk process with persistent movements. Our research suggests the human visual system may have a common strategy that drives the dynamics of human gaze during exploration

PSP1Files

Matlab Struct array of data for subject PSP1. Contains raweyedata which is of the form [time pupilrecognition xposition(pix) yposition(pix)] , xdat which is the value associated with the image and trial which gives the trial letter for the given data