was placed back, separating the resident from the intruder (postfight phase). A different resident was matched to each Wistar rat per day. Control rats (n = 32) were exposed to an empty defeat cage, once per day for a total of 5 days. From the first defeat session or empty cage exposure onwards, all animals were single housed and remained in social isolation for the rest of the experimental conditions, in absence of further sensory interaction with the stressor (residents). All experimental manipulations were conducted during the dark phase of a reversed 12‐hour light‐dark cycle (lights on at 19.00 hours). For the whole experimental period, animals received food and water ad libitum. All experiments were approved by the VU University Amsterdam Animal Users Care Committee.
