Georgetown Researcher Develops Low-Cost Touchscreen Chamber for Mice

Posted in News Stories  |  Tagged brain, cognitive function, mind, operant chamber, touchscreen chamber, translational research

(June 3, 2025) — Touchscreen chambers are powerful tools for scientists to study cognition — by training mice to recognize and tap different symbols, researchers can study complex brain functions like memory, reasoning and planning.

Just one problem: The price tag for these devices typically starts at around $70,000, putting them out of reach for smaller labs or researchers working under tight budgets.

“These are very important tools for translational research,” explains James O’Leary, PhD, a postdoctoral fellow in the Laboratory for Brain Injury and Dementia at Georgetown University Medical Center. “However, they also require significant financial capital to set up.”

O’Leary, a neuroscientist with a knack for engineering, decided to build his own. With a pilot grant from the Center for Neural Injury and Recovery (CNIR), he constructed four touchscreen chambers using custom software, off-the-shelf parts and a 3D printer, for less than $500 each.

He and colleagues plan to share the design with the research community so that other scientists can build and use the devices for their own projects.

“We see this as a resource that could support a wide range of investigators, including those in early career stages or working with constrained funding,” says O’Leary. “The goal is to contribute a flexible, accessible platform that can facilitate high-quality research across disciplines.”

Translational Analysis

Researchers have been using devices called “operant chambers” to study animal behavior and cognition for more than a century. Traditional models involved training mice or other small animals to push a lever, navigate a maze, or perform other tasks to earn a food reward.

Touchscreens were incorporated around 15 years ago, making the chambers more sophisticated; researchers could use the screens to present animals with more complex cognitive tasks to study behavior.

The touchscreens were also an important development for translational research, since similar tests could be performed in both animals and humans, helping to close the “species gap” that can sometimes be a challenge in animal research, O’Leary says.

“That means that data that we get from the preclinical mouse models are easier to translate into meaningful outcomes for human patients,” he says. “You’re comparing apples to apples.”

The devices can be used to study how conditions like brain injury, stroke and Alzheimer’s disease affect functions including memory, cognition and decision-making. They can also be a tool to measure how well new therapies reverse deficits or improve performance.

“The touchscreen chambers will bring a new depth to the cognitive research that’s occurring at Georgetown University Medical Center,” says Mark Burns, PhD, professor of neuroscience, director of CNIR and principal investigator of the Laboratory for Brain Injury and Dementia.

“We will now be able to test the ability of our mice to perform human-relevant cognitive functions — such as their ability to maintain focus and attention, as well as their ability to switch rapidly between different cognitive tasks. These types of cognitive problems are common in brain injury patients, and also in patients with dementia,” he says.

Humbling Experience

O’Leary, who had previously worked with commercial touchscreen chambers, designed his own prototype as a side project in 2018 while working on his PhD. For the new system, he wanted to develop a high-throughput and user-friendly platform that was also a low-cost alternative to the commercial systems.

He used custom software and open source hardware, including the Raspberry Pi, a small, simple, low-cost computer that can be easily programmed to interact with external devices like sensors, lights and motors that could be configured to dispense food rewards.

O’Leary purchased off-the-shelf parts to assemble the devices and used his lab’s 3D printer to create any additional components that were needed. Then it was time to put the devices to the test.

“After a lot of work designing and troubleshooting, the mice enter the chamber, and they’re interacting with the screen, you think it’s working nicely, and then the mice break the software in about 10 minutes,” O’Leary says.

The mice quickly learned that they could reset the system by triggering a sensor in the food dispenser, scoring extra food pellets. Others found a glitch that allowed them to release more food by rapidly tapping the screen in the seconds before an image appeared.

“Having the software get debugged by mice was very humbling,” O’Leary says.

Now that he has the touchscreen chambers, O’Leary is excited to use them in his team’s research. A current project involves studying neuromodulation therapy, a non-invasive treatment that involves placing electrodes on the outside of the scalp and administering mild electrical stimulation to enhance neural activity. The approach is used to treat a number of psychiatric disorders, and researchers are also studying applications in brain injury and stroke.

O’Leary explained, “We have seen promising results using transcranial electrical stimulation to facilitate functional recovery after TBI in standard behavioral maze paradigms, and we now plan to utilize the touchscreen chambers to further test its therapeutic benefit in more complex cognitive tests and gain more translational insight.”