What Is Memory?
Memory is the faculty by which the brain encodes, stores, and retrieves information. It is a record of experience for guiding future action.
Humans process stimuli first with their sensory memory; that information is typically held in the brain for less than a second, which may explain why most people report that when shown an object quickly, they feel like they take in more details than they're able to recall later. Next, the information is transferred to short-term memory or working memory, which allows someone to mull things over and hold key information in their mind. Finally, people store past events and patterns in their long-term memory, also known as episodic or semantic memory.
Different areas of the brain affect different aspects of memory. The hippocampus, for instance, is related to spatial memory, which helps the brain map the surrounding world and find its way around a known place. The amygdala, on the other hand, is linked to emotional memory.
Research is being done on the genetics of memory—and particularly a possible genetic root for Alzheimer's disease—but the science is still preliminary; it is unclear why some people remember things much more efficiently than others.
How Memory Works—or Doesn't
Memory is malleable, and many researchers believe that it can be improved. But it also tends to decline naturally as people age and it can be corrupted by dementia as well as brain injury, trauma, or repeated stress. Even without impairment, though, human memory is notoriously untrustworthy.
Studies have shown that people can be easily persuaded to conjure false memories—even suddenly “remembering” that they committed a crime that never actually occurred—while events that did occur can’t be recalled with perfect accuracy. Eyewitness memory is critical in criminal cases—but some experts wonder if the human brain should be fully trusted in a court of law.
How to Improve Memory
Memory naturally declines with age, but some people are able to stay mentally sharp. How do they do it? Genetics plays a role, but lifestyle choices—like exercising regularly, eating healthy, getting plenty of sleep, not smoking, and watching blood pressure and cholesterol levels—can have a huge impact. It’s also crucial to keep the brain active and challenged with new activities, such as learning a language, puzzles, hobbies, volunteering, and other activities.
People can boost memory with proven techniques like repeating what they hear out loud, writing things down, creating associations, and dividing new information into learnable chunks. By making healthy choices, a person can slow memory loss and improve cognition in their later years.