Have you ever been about to leave your house in the morning rush and realized that you have no idea where you last left your car keys? Have you ever asked yourself, did I schedule that dentist appointment for today or tomorrow? What was it that I needed to get at the store, or what is my boss’s kid’s name again?
The way our memory works is a complicated process, the details of which neuroscientists are still trying to understand. Our brain’s efforts to store information can be broken down into three modes: working memory, short term memory, and long term memory, each controlled by different parts of the brain.
Short term memory works to store information for a brief amount of time, typically without any processing of that information. Much of this activity occurs in the prefrontal lobe, the section in the front of the brain that is found to be highly developed in humans compared to other intelligent species. (And, it’s the reason we have such prominent foreheads!) Research suggests that there is a capacity limit along with an expiration date for the memories held in the short term memory bank, but the details of those limits are still highly contested. The George Miller Theory from 1956 suggested that we could only remember seven units of information at a time in our short term memory (i.e. seven digits or seven names). However, it has since been shown that this number can vary a lot depending on the type of information, the person doing the memorizing, and the situation.