Registered psychologist Lisa Rowbottom said June 8, 2026 [1], why people experience the phenomenon of déjà vu.

Understanding these mental glitches helps clarify how the human brain processes memory and perception. By examining the gap between immediate experience and long-term recall, psychologists can better understand the biological mechanisms of the mind.

Rowbottom said in Edmonton, Alberta, to explain the underlying psychological drivers of the experience [1]. The sensation occurs when a person feels an overwhelming sense of familiarity with a current situation, despite the fact that they have never encountered it before.

While the exact cause remains a subject of study, various theories attempt to explain the glitch. Some research suggests the feeling arises from a momentary misalignment in how the brain archives memories. This can create a loop where a current event is mistakenly flagged as a past memory [1].

Other perspectives expand on these mechanisms. For instance, some frameworks identify as many as seven different theories to explain why certain moments feel familiar [2]. These theories often involve the way the brain perceives spatial layouts, or recognizes fragmented patterns from previous, unrelated experiences.

Rowbottom said the experience is a common part of the human psychological landscape. The feeling typically lasts only a few seconds before the brain corrects the perception [1].

Despite the unsettling nature of the sensation, it is generally considered a benign occurrence in healthy individuals. The phenomenon highlights the complexity of the neural pathways that manage time and recognition [3].

“The sensation occurs when a person feels an overwhelming sense of familiarity with a current situation.”

The exploration of déjà vu by professionals like Rowbottom indicates a shift toward viewing the phenomenon as a window into cognitive processing. Rather than a mystical event, it is treated as a functional error in the brain's memory-matching system, providing researchers with data on how the mind distinguishes between the present and the past.