SSVEP Stimulator using MATLAB and Psychtoolbox
This is a 4 classes (or more) flickering stimulator for Steady State Evoked Potential experiment. The software generate four different target as can be seen in this video. Youtube demo video This tool presents a stable flickering frequencies which are usable for BCI applications.
Key parameters
- Current supported target: 4 different frequencies
- Supported frequencies: [6.66, 7.5, 8.75, 10, 12, 15, 20] Hz
Prerequisites:
- 64-Bit Matlab version 7.14 (R2012a) or later
- Psychtoolbox 3: http://psychtoolbox.org/
- System Requirements: any Nvidia or AMD graphic card, built-in Intel graphic cards do not work properbly (more at Psychtoolbox website)
How to use
- Install Psychtoolbox 3
- Download this repository to your computer
- Add lcms.m and square_flicker.m to MATLab searching directory
- Run square_flicker function. A window with 4 flickering frequency should be appeared on your desktop.
Discussion
- The methodology of this software https://beta.groups.yahoo.com/neo/groups/PSYCHTOOLBOX/conversations/topics/20675
Credits
- Josh, LCMS Matlab function (Least Common Multiple Set): https://www.mathworks.com/matlabcentral/fileexchange/24670-least-common-multiple-set
- Hubert Cecotti, Ivan Volosyak, Axel Graser. Reliable visual stimuli on LCD screens for SSVEP based BCI. The 2010 European Signal Processing Conference (EUSIPCO-2010), Aug 2010, Aalborg, Denmark.
- Psychtoolbox 3.
LICENSE - "MIT License"
Author: Bob and you.