We've all heard the term before. It's when we decide, usually at the very last minute, that we cannot go through with a major life change. There's stress, panic, often anxiety, or just plain scared. But what if our feet *actually* got colder under these scenarios. Science says they sure do.
Our bodies regulate our reactions to stress by modifying body temperature. Internal body temperature is based on the role of the Rap1A proteins and blood in each individual cell. When the brain signals a reactor in our cell, that protein activates and shifts from one area of the cell to another. And in June 2012, a team of scientists from the Research Institute at Nationwide Children's Hospital identified this interaction between the protein molecules and the receptors as the main biological cause of icy extremities.
"When we exposed the cells with chemicals that activated the Rap1A with a receptor, we found a shift in the cell's nucleus and a change in the cell's skeleton," says Dr. Maqsood Chotani, a principal investigator at the hospital. "We identified this receptor as the alpha-2C receptor and have found that it responds at times of stress to conserve body heat."
When the brain signals these receptors and shifts the proteins, the structure of the cells changes. The body reacts to this potential attack by then transporting blood from the extremities, like hands and feet, to vital organs like the brain, lungs and heart.
This is the body reaction to stress and threats (e.g. Fight or flight response) to maximize our chance of survival in threatening situations. Our heart beats faster and our circulating blood is redistributed to those parts of the body which acutely need it most such as the heart and skeletal muscle. This is at the expense of other body parts such as the stomach and skin, which are less critical to the acute stress reactions. The decrease in internal temperature in the hands and feet shifts the blood distribution and makes the skin cool and clammy.
Additional studies using infrared imaging have similarly shown heat loss from extremities during these times of stress.
So next time you are gearing up for public speaking or a wedding, bring an extra pair of socks so your feet don't get too cold.