How to modify sound stimuli
Sounds are controlled via stimulus tables. These are Matlab files that are prepared once during the design of each experiment. They stay the same across sessions unless you would like to change something. For the localization/discrimination task, a stimulus table is contained in the folder stim_tables.
Open the file allSounds_20dB.mat in Matlab. It contains a struct S with two fields, S.T and S.paramFile. The table S.paramFile contains the paths to the stimulus sound files, so if you like to completely change the sounds that are used, you need to change their paths here. But we are going to use the same sounds and play them from different speakers. Many specifics related to the sounds are controlled in the table S.T. It looks like this
Currently, each sound is played from the speakers above the target interaction area (IA). The speakers are numbered 1...12. Two speakers are placed above each of the six IAs. Instead of playing a sound directly above the target, we would like to play it from the speakers left and right of the target. So for example for IA3, currently speakers 5 and 6 are used, and we would like to change that to speakers 4 and 7. After making all changes, S.T will look like this
Then save the modified S by running
save('allSounds_20dB_BiasStudy.mat', 'S')From now on, you can simply load your modified stimulus table from the task GUI.
Are the rats going to learn this modified task?