Experiments
Visual method
In the visual method, lay trials out in one or more tables in a spreadsheet. You can use any spreadsheet app, but Google Sheets is most common since it gives you dropdown menus and quick docs. Rows are trial definitions. Columns are object properties. Values are MATLAB values or expressions. You only need to write each distinct row once, and in any order. Then use one more MATLAB expression to set a list of trial definitions to run through, including any repetition and ordering. Save to an Excel file, use the command loadExperiment in MATLAB to load it, and runExperiment to run.
For example, the two tables below would make an experiment that runs two repetitions of three distinct trials, all in random order. In each trial, a picture of an animal shows at a height of 10 degrees visual angle. The picture stops showing when the subject presses any key. Experiment results report picture file name and response latency for each trial. (This is an extremely minimal example! See examples and demos for more.)
Coding method
You can always use the coding method instead if you prefer. Here make objects, set properties, and define trials in a MATLAB script. You can use for loops through conditions to automate defining trials. This isn't really code in the usual sense—more like a list of statements setting parameters. For example, this script would build and run the same experiment as above:
(Without PsychBench)
Just for comparison, here is some compact Psychtoolbox code that would run the same experiment, with the same timing precision and error handling. The difference with/without PsychBench is noticeable here but it balloons up for more realistic experiments.
