PsychoPy Stimuli

Stimuli based on PsychoPy play a special role in rewardGym, as they allow for both stimulation, fine control over timing, logging and simulation of experiments.

See some examples rewardgym.psychopy_render, which can be accessed via the rewardgym.psychopy_render.stimuli module.

These stimuli are added to the environment as a list, so that at each state a number of stimuli are displayed after another. Typically ending in an rewardgym.psychopy_render.stimuli.ActionStimulus.

The Stimulus Class

The stimulus class has three main methods: setup, display, and simulate.

Setup

The role of the setup method is to instantiate the different PsychoPy objects, that are used for displaying stimuli on the screen. In principle, this method should only take the current window object as an argument.

All properties of the PsychoPy objects to be displayed (filenames, images, text, etc.) should be added to the class during __init__.

Display

The display method is used by the rewardgym.environments.psychopy_env, to render the stimuli onto the display.

The display method inside the environment has access to:

• the current window object

• the current logger object

• the current condition

• the total reward

• the current reward

• the current location of the agent

• and the action issued previously

Simulate

Finally, there’s the simulate method, which mirrors the display method. This is used to simulate full log files. In many cases you can use simulate method inherited from the rewardgym.psychopy_render.stimuli.BaseStimulus, class.