Have you ever walked into a room and forgotten what you were there to do, or were about to say something and immediately forgot what you meant to say?
The human brain typically manages a vast amount of input information, thoughts, and actions, but sometimes it appears to misfire. So, what really happens when we forget something we just thought about?
To understand why we forget, we first need to explore how we remember. Professor of Psychology Susanne Jaeggi at Northeastern University in Boston, USA, explains: “Memory is not just one thing; there are many different factors that contribute to memory, and these factors are all related to different cognitive processes.”
Working memory, or short-term memory, malfunctioning can lead to immediate forgetting. (Photo: Peter Cade/Getty Images).
It is also important to note that there are two types of memory: long-term memory and short-term memory (also known as working memory).
Long-term memory is a vast, multifaceted type of memory that involves knowledge, experiences, and skills, stored in the brain for an extended period, ranging from hours to an entire lifetime, while working memory only lasts in our minds for a few seconds or minutes.
Working memory functions like “a sketch of active thought” – says Professor of Neuroscience Earl K. Miller at the Massachusetts Institute of Technology. Each new piece of information, every inner conversation, and sensory inputs traverse working memory, and certain characteristics of working memory can explain why we can forget these thoughts and intentions so quickly.
First, working memory has its limits. There has been much debate about how far this limit extends and how to measure it, but psychologists estimate that each person can hold about 4 to 7 “items” of information at any one time, such as letters, numbers, words, or phrases.
Instead of remembering all these “items” at once, the brain cycles through them one at a time, making the process of thinking and processing information feel like being lost in a jumble.
Second, the brain quickly purges unnecessary information from working memory to make room for new information. Therefore, unless these short-term memories are transferred to long-term memory, they quickly fade from active thought.
Since the brain cannot multitask effectively, it must “juggle” different thoughts while working memory processes various ideas. This requires effort and conscious focus, monitored by the prefrontal cortex, which is involved in learning, decision-making, and complex reasoning.
If attention focuses solely on one of these thoughts or shifts to a new one, the brain will lose track of the previous thoughts. “All the ‘balls’ get dropped, and that’s why you forget everything” – Professor Miller states.
The brain is particularly prone to “dropping the ball” from working memory when fatigued or influenced by alcohol or other stimulants. Aging is also a contributing factor. Working memory functions best in a person’s 20s and begins to decline from middle age onward.
However, for those who forget frequently enough to impact their lives, scientists have a few training tips.
First, we need to avoid multitasking and thinking about too many things at once. When juggling many tasks, it is easy to forget. If you have thought of something and then forgotten it, recreating the situation may help you remember.
For instance, returning to the room you stepped out of or trying to recall each thought in reverse order can provide the brain with some stimulation to retrace the memories from a few seconds ago and recover the forgotten thoughts.
