Multiple Stresses Killed Snail Memory
When pond snails, a model organism used in memory research, faced multiple stressors simultaneously, it forgot a behavior it had trained for. Allie Wilkinson reports.
By Allie Wilkinson

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Stress sucks. It can affect your body and mind.
Previous research has shown that stress can even hinder our ability to remember. But these studies have typically focused on one stress at a time. What happens when we face multiple stresses?
Researchers looked at pond snails, often used in memory research. They trained the snails to reduce how frequently they breathe out of water. They then tracked whether the snails remembered their training after being stressed. The snails’ memory was considered intact if they reduced their attempts to breathe when removed from water.
Two common stressors—low levels of calcium, necessary for strong shells, and overcrowding by other snails—can happen in combination in the wild.
Individually, these stressors only blocked the formation of new long-term memories in the snails. But combined, they caused the snails to forget their training, that is, they prevented any new memories from being formed. The study is in the journal PLoS ONE. [Sarah Dalesman et al., Combining Stressors That Individually Impede Long-Term Memory Blocks All Memory Processes]
It’s thought that these snails and mammals have similar responses to stress. Of course, when stressed out, we should remember to breathe more, not less.
—Allie Wilkinson
[The above text is a transcript of this podcast.]
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