# readme.md

Please cite our paper if you use our code or data.
Burlingham, C.S. & Heeger, D.J. (2020). Heading perception depends on time-varying evolution of optic flow. PNAS.

## Organization
/main_experiments/
	/em/ - envelope motion data
	/pm_first/ - phase motion (first flow field) 
	/pm_first__replication/ - phase motion (first) replication
	/pm_last/ - phase motion (last flow field)
	/tvpm/ - time-varying phase motion

/control_experiments/
	/pm_last__double_patch_density/ - phase motion (last) with double the density of plaid patches
	/pm_last__single_plane/ - phase motion (last) with a single fronto-parallel plane instead of two planes
	/tvpm__single_plane/ - time-varying phase motion with a single fronto-parallel plane instead of two planes

* Within each of these subdirectories are a number of directories labelled /Ox/, where x is the number of the observer.
* These /Ox/ directories contain .mat files with binary choice data from the experiments. 

* Note: eye data (.edf files) are available upon request due to large file size (> 4 gb). Email charlie [dot] burlingham [at] nyu [dot] edu.

## Usage
/analysis/choiceData/
• run OFAnalysis.m to fit a psychometric function to choice data and to extract heading bias and variability. 
• To recreate figs 4 and S1-3, run this function within an /Ox/ directory containing data (.mat) files, which are automatically outputted by MGL.
• run OFAnalysis_controlExpts.m on data from the control experiments to recreate figs S5 and S7. 

/analysis/eyeData/
• run wsEyeAnal.m within a directory containing .mat (MGL choice data) and .edf (EyeLink gaze data) files to reproduce eye movement analyses detailed in the supplementary appendix.