Sometimes we hear a song, or smell a certain odor that reminds us of something that happened in the past. It is like rewinding a scene with all its details and incidents. This may seem a random occurrence to us, but it turns out that this is an intentional function of the brain. Our five senses leave memory imprints on different parts of our brains to help us retain information later.
Sight is one of the senses humans rely on heavily; however, it is not perfect when it comes to recalling memories. You would know this if you have ever struggled to recall the face of someone upon meeting them again. There are times when your sense of sight serves you well, though. Information from your ocular organs travels to your temporal lobe, leaving an imprint on your brain; this information is what you use to recognize people and movements. Without this information, you would not be able to recognize anyone you know by sight alone.
As for sound, the human mind has the ability to recognize tune, rhythm, and wording of a song after a lapse of time without hearing it. You may be familiar with these phenomena if you can recall children’s rhymes immediately when you hear them again. Not only does your brain remember the information from the songs well, but it also remembers voices too. For example, you may go a long time without hearing a certain voice, but you can recognize it immediately when you hear it again. Information attained from sound stores itself in the auditory cortex of the brain.
A smell, on the other hand, can bring a flood of memories and take you back to a moment in the past. What happens is that your nose sends signals to your olfactory cortex in your brain so you can recognize the smell. From there, the information travels to the limbic system of your brain, which links that smell to past events, bringing your memories to the forefront of your mind.
Finally, touch is an important sense we use from birth to experience the world around us. Sensations from your skin stay with you in the form of impulses. For example, when you experience something painful as a burn, your mind will immediately associate the thing that burned you with pain. From that point, you will condition yourself to avoid that pain. You also do the same for pleasurable sensations like softness. The signals from your skin travel to the insula cortex in your brain and stay there for future reference.
It is amazing how our senses act as a memory inventory. The next time you hear a song or smell a certain odor that takes you back to pleasant times, remember that it is your senses that take you there.
References
www.nature.com
www.ehow.com
*The original article was published in SCIplanet printed magazine, Summer 2013 issue.
Cover image by Freepik