Deja vu is a state where a person feels like they have seen or experienced a place, event or situation before. This may be because the brain stores information about previous experiences and comparisons, and finds similar elements in new experiences. Deja vu can cause a feeling of déjà vu, which can manifest itself in different forms, such as a feeling of fear or excitement, forgetfulness, confusion in time and space.
Deja vu was first described in 1896 by French psychiatrist Emile Boirac, who defined it as a special state of memory in which memories appear new even though they had previously been retrieved. Since then, many studies and experiments have been conducted to study deja vu and related phenomena. For example, some studies show that deja vu is associated with the process of perception, storage and processing of information, as well as with emotions and memory.
Causes of deja vu can be due to various factors such as fatigue, stress, medications and other medical conditions. Some people experience deja vu more often than others and may experience it under a variety of conditions, including travel, sports, noisy places, alcoholic beverages, and some drugs.