An Open Source Platform for Presenting Dynamic Visual Stimuli

Abstract

Operant behavior procedures often rely on visual stimuli to cue the initiation or secession of a response, and to provide a means for discriminating between two or more simultaneously available responses. While primate and human studies typically use LCD or OLED monitors and touch screens, rodent studies use a variety of methods to present visual cues ranging from traditional incandescent light bulbs, single LEDs, and, more recently, touch screen monitors. Commercially available systems for visual stimulus presentation are costly, challenging to customize, and are typically closed source. We developed an open-source, highly-modifiable visual stimulus presentation platform that can be combined with a 3D-printed operant response device. The device uses an eight by eight matrix of LEDs, and can be expanded to control much larger LED matrices. Implementing the platform is low-cost (<$70 USD per device in the year 2020). Using the platform, we trained rats to make nosepoke responses and discriminate between two distinct visual cues in a location-independent manner. This visual stimulus presentation platform is a costeffective way to implement complex visually-guided operant behavior, including the use of moving or dynamically changing visual stimuli. Significance StatementThe design of an open source and low cost device for presenting visual stimuli is described. It is capable of presenting complex visual patterns and dynamically changing stimuli. A practical demonstration of the device is also reported, from an experiment in which rats performed a luminance based visual discrimination. The device has utility for studying visual processing, psychophysics, and decision making in a variety of species.

Noradrenergic regulation of two-armed bandit performance.

“…Behavioral devices were controlled and data were collected using custom-written code for the MedPC system, version IV (Med Associates). Visual stimuli were presented using custom-made LED matrices (Swanson et al, 2021). Visual stimulus devices were placed above each nosepoke port, outside the box, to signal active trials.…”

“…Finally, the task transitioned from visually and spatially guided to purely spatially guided behavior. The difference in the number of illuminated LEDs in the LED matrices (Swanson et al, 2021) between the correct and incorrect side was slowly decreased over several sessions, starting from 10 or 8 versus 0 LEDs, until both cues had an equal number of LEDs illuminated for each trial.…”

Noradrenergic Regulation of Two-Armed Bandit Performance

“…Behavioral devices were controlled and data was collected using custom-written code for the MedPC system, version IV (Med Associates). Visual stimuli were presented using custom-made LED matrices (Swanson et al, 2021). Visual stimulus devices were placed NORADRENERGIC REGULATION OF TWO-ARMED BANDIT PERFORMANCE 7 above each nosepoke port, outside the box, to signal active trials.…”

Learning to Choose: Behavioral Dynamics Underlying the Initial Acquisition of Decision Making

“…Building on the work of Kacelnik et al (2011), we designed a behavioral task to isolate learning the values of individual stimuli from learning to make choices between stimuli (Fig 1). Using an open-source two-alternative forced-choice task (Swanson et al, 2021), we first trained rats to learn the reward values of the stimuli. Then, we introduced choice trials with pairs of stimuli and measured how the rats responded when making choices for the first time.…”