Lab Mice Rehomed to Fields Show Reversed Anxiety Levels, Study Finds
A recent study conducted by researchers from Cornell University has revealed fascinating insights into the behavior of laboratory mice when allowed to roam in a large outdoor enclosure. The findings suggest that ‘rewilding’ these mice may prevent the development of lab-induced fear responses and potentially offer a new perspective on studying anxiety in animals.
According to biologist Matthew Zipple, who led the study, the mice exhibited a remarkable reversal of anxiety behavior after just one week in a naturalistic environment. This observation raises questions about the conventional methods used to induce and measure anxiety in lab animals, such as mice, and sheds light on how anxiety responses may originate.
The standard method for inducing anxiety in mice involves the use of an elevated plus maze (EPM), where the animals are exposed to both enclosed and open spaces. Typically, mice display fear responses by retreating to the enclosed areas, indicating a heightened level of anxiety. This behavior is known to be resistant to traditional anti-anxiety drugs.
When 44 mice were released from their lab cages to explore the outdoor environment, researchers noted a significant shift in their behavior. The mice engaged in various natural activities such as burrowing and climbing, leading to a reset of their fear responses when reintroduced to the EPM. This reset effect was observed in mice of different ages, suggesting a universal impact.
The implications of this study extend beyond animal behavior and could offer insights into human anxiety as well. The researchers suggest that exposure to a diverse range of experiences may play a crucial role in shaping anxiety responses. A limited set of experiences could potentially lead to heightened anxiety when faced with unfamiliar situations.
Neurobiologist Michael Sheehan emphasizes the importance of understanding how our environment influences anxiety responses. He suggests that a broader range of experiences could help individuals calibrate their responses to novel stimuli and reduce inappropriate anxiety reactions.
These findings challenge traditional notions of anxiety research in laboratory settings and highlight the need for a more holistic approach to studying anxiety in both animals and humans. By reevaluating the impact of environmental factors on anxiety levels, scientists may uncover new strategies for managing anxiety disorders and promoting mental well-being.
The study has been published in Current Biology and marks a significant step towards redefining our understanding of anxiety and its complex relationship with our surroundings.
