Cornell researchers have developed a wireless device that can record animals' brain activity as they move and interact in natural settings, allowing scientists to study behavior that has been difficult to reproduce in laboratories.
The device, called the Wireless, Interactive, Lightweight Datalogger, or WILD, weighs less than a dime and was tested on groups of mice for more than two weeks at a time, according to a proof-of-concept paper published Sept. 10 in Nature Methods.
Recording brains in natural settings
WILD uses flexible probes that can monitor groups of neurons for months. Researchers can add modules to record movement and orientation, vocalizations and eye movements, or to manipulate brain activity with pulses of light and electricity.
The system can also be programmed to send signals when it detects a specific brain pattern or behavior. It records continuously for three to nine hours depending on battery size and can operate longer when set to conserve power while animals are dormant.
Researchers tested WILD in a field enclosure north of Cornell's campus, recording mice as they explored and interacted. The experiments produced what the team described as the first field recordings of “place cells,” neurons that activate as an animal moves through and forms a mental representation of its surroundings.
Co-senior author Antonio Fernandez-Ruiz said the cells shared some traits with those observed in laboratory studies but also showed differences the team is investigating. The work is intended to help scientists compare neural activity under controlled and natural conditions.
Existing approaches often rely on tethers or heavier wireless equipment that can interfere with movement. Cornell said those systems also are poorly suited for outdoor conditions where equipment faces moisture and humidity.
WILD was designed to withstand the elements and can be assembled inexpensively with different combinations of modules. The team made its materials open source so other researchers can build and adapt the system.
New questions about social behavior
Co-senior author Azahara Oliva said the device combines high-resolution neural recordings with observations of animals in nature. That opens studies of how groups form colonies, care for young, defend territory, build nests and coordinate other complex tasks.
Collaborators are already applying the technology to birds, bats and monkeys. Oliva and Fernandez-Ruiz plan to use it to examine group coordination, seasonal effects on the brain, neurodivergence in social settings and the long-term effects of psychedelics.
The team also plans modules that could monitor heart rate, temperature, glucose and other measures of an animal's physical condition. Those readings could be compared with brain activity and behavior over time.
Cornell said the interdisciplinary project moved from an early prototype to field testing in two years, drawing on neuroscience, engineering and computer science expertise as well as the Cornell NanoScale Facility and AI for Science Institute.
Research associate Zifang Zhao led development as first author. Other authors include doctoral students Hongyu Chang, Praveen Paudel, Jaehyo Park and Can Liu, and undergraduate Maria Aurelio.
The research received support from the National Institutes of Health, Whitehall Foundation, David and Lucille Packard Foundation, Alfred P. Sloan Foundation, Simons Foundation, Pershing Square Foundation, Pew Charitable Trusts and Mong Family Foundation.
FingerLakes1.com is the region’s leading all-digital news publication. The company was founded in 1998 and has been keeping residents informed for more than two decades. Have a lead? Send it to news@fingerlakes1.com.