Andy’s Quick Hits (95): Second-Hand Stress is Also Stressful (and damaging to the brain)

What do you mean by second-hand stress?
Well, obviously we know that stress is bad for you if you experience it. For example, in research there is something known as social defeat stress: being beaten by an opponent which is a major stressor in the animal world and in many human beings. In this group of experiments, on mice, the researchers measured the impacts of viewing defeat of other mice.

And this also proved stressful?
Yes, indeed this also proved stressful.

And how?
Well, that is the interesting part. They looked at the specific mechanisms. Mice don’t answer surveys but we can actually look into their brains and measure what the impacts are.
They found that there were “psychological” symptoms such as social withdrawal but also, for example, a significant decrease in the survival rate of new-born neurons in a region called the dentate gyrus, a region in the hippocampus responsible for sensory perception and memory.
And this condition persisted for up to four weeks, after “stressing” the mice.

Oh wow — so second-hand stress also could be measured in the brain?
Yup — kind of worrying. Obviously identification can…