Overview
- Penn State scientists report in Nature Neuroscience that tensing belly muscles pushes blood through veins along the spine, which nudges the brain and changes pressure in the skull.
- Using two-photon imaging in head-fixed mice on treadmills, the team saw the brain shift just before each step, then reproduced the motion by applying light pressure only to the abdomen.
- Breathing or heartbeat did not cause the same brain movement, identifying abdominal contraction as the key trigger.
- Micro-CT maps of a vertebral venous network and computer models that treat the brain like a sponge show these tiny shifts can drive cerebrospinal fluid out into the subarachnoid space.
- The effect could occur during simple acts like walking or holding posture, but any benefit in people is unproven and will need tests in more natural setups.