Data and code: Single cone photoreceptors experience global image statistics through gaze shifts
Creators: name: XX, YY
Publisher: name: Zenodo
Year: 2024

description: Title of the study: Single cone photoreceptors experience global image statistics through gaze shifts

Short summary of the study: Our visual experience does not merely reflect a static view of the world but is a dynamic consequence of our actions, most notably our continuously shifting gaze. These shifts determine the spectral diet of any individual cone photoreceptor. The aim of this study was to characterize that diet and its relationship to scene adaptation. Gaze shifts were recorded from observers freely viewing scenes outdoors for five minutes. Hyperspectral images of the scenes were also recorded from the observer’s eye position. As a control, gaze shifts were also recorded from observers viewing the images on a computer-controlled display in the laboratory. From the hyperspectral data, spatially local histograms of estimated excitations in long-, medium-, and short-wavelength-sensitive cones were accumulated over time at different retinal locations. A global illuminant change was then introduced to test how well local retinal adaptation discounted its effects. The results suggest that over short periods individual cones tend to experience the statistics of full scenes, with local adaptation compensating for illumination changes almost as well as global adaptation. This compensation may help to maintain our stable local perception of scene colour despite changes in scene illumination.

Code version: ver 2

Dependency: Psychtoolbox-3 http://psychtoolbox.org/

Overview and instructions:Welcome to the repository for "Single cone photoreceptors experience global image statistics through gaze shifts"! Here, you’ll find all the files and MATLAB source codes you need to run simulations, analyze results, and create the figures presented in the manuscript.

To generate the figures, add this respository to the path, simply navigate to the parent folder ('Gaze_HSimages') and run GHS_main.m. This will call the other codes needed to carry out the analysis and produce the figures. All figures will be saved in the folder "fig".

Please keep in mind that a full simulation of local adaptation can take some time—up to several weeks—and the resulting files may require over 1 TB of storage space. To make things easier for you, we’ve uploaded a summary file ("DeltaE_adaptation_summary.mat") that you can use for figure generation without having to run the full simulation.

If you’re interested in running the code and generating summary files on your own, just uncomment the following lines in "GHS_main.m":

% GHS_run_simulation

% GHS_analysis_simulation

 

All gaze data and hyperspectral images are stored in "allData.mat" within the "data" folder. The field name of the structure variable "allData" should provide sufficient interpretation.

The gaze data is represented in x, y coordinates, where x is horizontal and y is vertical.

The coordinates x, y = 0, 0 correspond to the upper left corner of the image. An increase in x shifts the gaze to the right, and an increase in y shifts the gaze downward.