Empathy Assay

In observational fear learning, an observer animal watches a conspecific demonstrator receive foot shocks through a transparent partition. The observer receives no shock, yet freezes — acquiring a fear response from someone else's experience. The behavior is used as a rodent model of emotional contagion, the affective component that underlies empathy, and it is sensitive to familiarity: observers typically freeze more when the demonstrator is a cagemate than a stranger.

The assay lives or dies on its controls. The observer can pick up distress through sight, sound, and smell at once, so a result means little without a no-shock demonstrator condition to show the freezing is not simply a reaction to the apparatus, and a demonstrator-freezing measure to show the shock was delivered at all. An observer that fails to freeze while the demonstrator freezes normally has a social transmission deficit; an observer that fails to freeze because the demonstrator never froze is a failed experiment, not a phenotype.

ConductVision scores both chambers at once, so observer and demonstrator freezing, proximity to the partition, and the synchrony between the two animals come out of the same recording.