Data Collection as Environmental Enrichment: Automated Behavioral Measurement in Voluntary Home Cage Operant Tasks

Biomedical research suffers from a translation gap, where most treatments that seem effective when tested on animals turn out not to work in human patients. This is likely due in large part to differences in how animal and human experiments are performed, and a key step in overcoming this problem is to treat animals like we treat human patients. This means making their well-being a top priority and giving them control over stressors in their housing and testing environments.

Cognitive tests of learning and memory are typically performed in an operant chamber outside of the home cage. Many of the aversive features of these hand-run tests – handling by experimenters, temporary separation from social companions, and being placed in unfamiliar environments – can be eliminated by testing animals on a voluntary basis, inside their home cages. Automated home cage operant tests further help ensure that animals volunteer to be tested only when appropriately motivated. Properly designed tests that tap into animals’ intrinsic motivations and match the level of cognitive challenge to their level of skill can even be a valuable form of environmental enrichment.

Aversive features and low or fluctuating motivation associated with conventional hand-run operant tests can negatively impact cognitive performance. Automated home cage operant tests may then more accurately assess learning and memory. Large-scale replication studies further suggest that results of these tests are more consistent across different laboratories. By yielding control to experimental animals and allowing them to be tested voluntarily rather than through coercion, automated home cage operant tests may additionally pave the way towards improved translation from animal to human patients. If so, this would serve as a prime example of how good animal welfare can lead to good science, with improved quality of life for experimental animals and accelerated development of treatments for human patients.