Why does holding a baby bring so much joy? For mice, tending to their young is its own reward. This video shows in real time how the brain drives maternal instincts. See the EKG-like meter running across the screen? Each spike is a shot of dopamine released by the brain at the exact moment a mother mouse picks up a pup.
Cold Spring Harbor Laboratory Associate Professor Stephen Shea and Postdoc Yunyao Xie traced this neurological response to a process called reinforcement learning. Each shot of dopamine creates the expectation of future rewards, driving mouse moms to pick up their pups again.
Understanding how this works in mice gives researchers a clue about how our own brains encourage social interactions. It could also teach us something about autism and other neurodevelopmental disorders.
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