This experiment is designed to measure radial direction bias at given eccentricities and polar angles. The presented stimulus during each trial is a drifting grating, and the subject is instructed to determine whether the direction of drift is (a) clockwise or (b) counterclockwise relative to an internal reference frame. The internal reference frame will either be the radial axis (relative to central fixation), or the tangential axis (relative to central fixation). This experiment includes 3 modalities: practice, thresholding, and experimental (default). The thresholding uses a staircase method to determine optimal spacing of the clockwise/counterclockwise tilt relative to the internal reference frame.

Experimental Code Requires:

PsychToolbox (version 3 used)

Palamedes Toolbox: http://www.palamedestoolbox.org (used for staircase procedure)

Analysis Requires:

Palamedes Toolbox: http://www.palamedestoolbox.org (not used for fitting, just for plotting)

Optimization Toolbox (Matlab) for FitCumNorm function

Experiment Running instructions:

In Matlab run Experimental_Setup/Main/expLauncher

Storage & Backup:

Scripts & behavioral data: github.com/raniaezzo/RadialBias_pilot1 All images (.fig, .bmp, .png,) and eyelink files (.edf) are ignored to git push.

Data storage: eyetracker PC, Rania local PC & Rania Google Drive

Data dictionaries in Experiment folder for more details on data and parameter variables saved from experimental code