The feeling you are describing is commonly known as "déjà vu," which is a French term that translates to "already seen." Déjà vu is the sense of familiarity or the feeling that you have experienced a current situation or moment before, even though you know it's not possible. It can be a strange and sometimes unsettling experience, but it's relatively common, with around two-thirds of people reporting having experienced it at some point in their lives.
There isn't a definitive answer to why déjà vu occurs, but researchers have proposed several theories:
Memory processing: One theory suggests that déjà vu occurs when there is a temporary hiccup in the brain's memory processing. The brain may mistakenly label the current experience as a memory, which leads to the feeling of familiarity.
Dual processing: Another theory posits that déjà vu arises when the brain processes information through two different pathways: one for immediate experience and another for memory recall. Sometimes, these pathways may get temporarily out of sync, causing the current experience to feel like a memory.
Mismatched input: According to this theory, déjà vu occurs when there is a slight delay in processing information from one of the senses. As a result, the brain perceives the current experience as both familiar and new at the same time.
Unconscious familiarity: Some researchers suggest that déjà vu might occur when an experience activates memories that are stored in the brain's unconscious regions. Even though you don't consciously remember the previous occurrence, your brain recognizes the similarities and generates a feeling of familiarity.
Attention and perception: Certain environmental cues or stimuli may subconsciously remind you of past experiences, leading to a sense of déjà vu when those cues resurface in your current environment.
It's important to note that déjà vu is considered a normal phenomenon and is not usually a cause for concern. It often happens spontaneously and rarely indicates any underlying health issues. However, if you experience déjà vu frequently or if it's accompanied by other unusual sensations or cognitive difficulties, it might be worth discussing with a healthcare professional to rule out any potential neurological issues.