Your Brain is a Time Machine: The Neuroscience and Physics of Time

by Dean Buonomano

Classical conditioning is the primordial algorithm animals use to predict what is about to happen next.

There is also a dark side to wheel running. When rats are kept on restricted diets, running wheels can be detrimental to their health. Rats with limited access to food will increase their wheel running and, compared to rats given the same amount of food but no access to a running wheel, exhibit more health problems and an increased mortality rate.

During Galileo’s life, however, the properties of the pendulum were used to create one of the first medical devices invented: the pulsilogium. It consisted of a weight on a string, which was attached to a horizontal ruler. The ruler allowed the length of the string to be shortened or lengthened. By changing the length of the string, the pulsilogium allowed the doctor to adjust the period of the swing of the pendulum to match the heartbeat of the patient. Thus the length of the string provided a fairly reproducible measure of heart rate.7

Fortunately, how we balance the trade-offs between short- and long-term outcomes is not hardwired into our genes. Delaying gratification and making optimal intertemporal decisions is a process that benefits immensely from practice, education, deliberation, and simply stopping to think about the future. Studies show, for example, that temporal discounting rates can be extended—shifted from impulsive to more patient decisions—by having people engage in mental time travel as they make decisions.