We know for a fact that animals naturally and instinctively shake off their stress. Whether or not they do it while singing Taylor Swift’s Shake It Off is another matter. We also know for a fact that humans don’t do this instinctively. We’re more likely to engage in therapy of the alcohol, retail, or epicurean kind. That physical shaking is a signal from the brain’s limbic system (responsible for the fight/flight/freeze response) that the threat has passed and the nervous system can return to pre-stress levels. In humans, when the limbic system takes over, the prefrontal cortex can go offline temporarily, making it impossible to think our way out of the situation.