Chronic stress has been a pervasive factor during the new-normal of the COVID era. Notably, although moderate stress is critical for adaptation in a changing world, prolonged stress exposure can lead to an array of mental health conditions, often associated with structural changes in brain regions that affect emotional learning, such as the amygdala, the frontal cortices, and the hippocampus. To better target treatments, it is critical that we improve our understanding of the physiological and behavioral consequences of increased exposure to chronic stress. To this end, rodent behavioral tasks have been instrumental for probing symptoms of stress-induced behavioral change, including the social interaction test, the sucrose preference test, and the forced swim test to study increased social avoidance, anhedonia, and decreased motivation, respectively. However, one notable behavior that has received less attention thus far, is avoidance of aversive stimuli. Given that periods of increased chronic stress are also often coupled with frequent occurrences of aversive cues and events, this poses an important question for the field. In this issue of Neuropsychopharmacology, Shukla and Chattarji [1] tackle this question by tapping into the rodent behavioral repertoire in response to different frequencies of ultrasonic vocalizations (USVs), which rats use to communicate their affective states.

One interpretation comes from an emerging field in rodent research that focuses on the role of prior experiences in developing pro-social tendencies. This work shows that prior experience determines whether a rat is likely to help another rat in distress. A lack of familiarity with the distressed rat or situation can result in a decreased likelihood to behave pro-socially and a reduced tendency to help conspecifics [3]. It is therefore possible that stressed rats display a form of empathic-like behavior as manifest via decreased avoidance, wherein their previous exposure to stress makes them more likely to approach distressing USVs than their stress-naïve counterparts. This behavior may rely on partially overlapping neural circuits and communication patterns with those of fear learning.

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