MarmoAAP is an apparatus for the study of cooperative behaviors, which allows a pair of marmosets to coordinate how they pull a lever to both obtain juice. Image credit: Olivia Meisner (CCBY 4.0)
Cooperation is one of the most important and advanced forms of social behaviour, yet studying it in laboratory settings can be particularly challenging. This is partly because animal species typically used in research do not cooperate in a way similar to humans.
More recently, marmosets have gained recognition as an important model for studying collaboration, as these small primates naturally exhibit cooperative behaviours. However traditional research methods have struggled to capture these dynamics in a reliable and detailed way. A lack of approaches that allow researchers to methodically prompt naturalistic behaviours in freely moving animals under various controlled circumstances has hampered efforts to study the factors that influence cooperation. This limitation has also hindered investigations into the brain processes that underpin this unique social trait.
To address this gap, Meisner et al. developed MarmoAAP, an apparatus that allows two marmosets in adjacent, transparent enclosures to observe each other and coordinate their actions so they can simultaneously pull levers and both receive a reward. This tool is compatible with advanced tracking technologies to monitor behaviour and brain activity.
Testing revealed that the marmosets exhibited cooperative behaviour much more consistently and in greater numbers with MarmoAAP than in previous experiments using traditional, non-automated methods, making the apparatus an effective tool for studying this complex social behaviour.
In addition to studying cooperation, MarmoAAP offers a standardised platform for testing the effects of drugs in marmosets, which could help develop new treatments for further testing in humans. Importantly, performance on the task could be precisely quantified using the detailed metrics provided by the apparatus. This is crucial for better understanding the factors that influence cooperative ability, and how these behaviours can be enhanced or disrupted. Neuroscientists could also use this combination of adaptable design and high-resolution data gathering to better understand brain activity in a wide range of complex primate behaviours.
