Before running any demos please make sure you have the latest version of PsychBench since they may use features only available in recent versions. You can type pb_update at the MATLAB command line to check.
Below are links to demo experiment scripts in the coding method. Copies are also included in PsychBench in <PsychBench folder>/demos, so you can run them from there.
Below are links to demo experiment spreadsheets in the visual method (Google Sheets files). You can make copies in your own Google account if you want to modify them (Google Sheets → File → Make a copy) and download them to run them (Google Sheets → File → Download → Microsoft Excel). If there is no link then we haven't made the visual method version yet but it's coming soon.