Author: Hanni Yang
Editors: Junyu Zheng, Emily Yu, Rachel Chen
Artist: Helen Zhang
Have you ever felt like you’ve already experienced something before, almost like a replay of a moment from the past? That phenomenon is called déjà vu, a peculiar sensation that has intrigued minds for centuries. Déjà vu is a French term meaning “already seen.” It is a captivating mystery that has fascinated psychologists, neuroscientists, and philosophers for centuries. People from all walks of life have felt it, both fleeting and intense, sparking curiosity about how our minds work and how memories unfold.
Psychological perspectives provide valuable insights into the phenomenon of déjà vu. Theories related to memory, such as the dual processing theory, suggest that déjà vu results from the simultaneous processing of incoming information through different brain pathways, leading to the misinterpretation of a current experience as a memory. Likewise, according to divided attention theory, déjà vu can occur when attention is divided between experiencing a current event and recalling similar experiences in the past, causing the current situation to feel familiar. Neurological explanations suggest that déjà vu involves brain regions such as the hippocampus and temporal lobes, which are often disrupted in conditions such as epileptic seizures. These disturbances may contribute to the frequency and intensity of déjà vu events. Additionally, neurotransmitters critical to memory processing, such as dopamine and glutamate, may affect the feeling of déjà vu by influencing brain function. Recent studies from PubMed have explored therapeutic avenues for cognitive deficits, specifically targeting 5-HT4 receptors. In a study of healthy volunteers, short-term administration of the 5-HT4 partial agonist prucalopride improved behavior and neural memory processing. These findings highlight the potential of 5-HT4 receptor modulation to enhance cognition, offering hope for treating cognitive impairment in psychiatric disorders.
Apart from psychological perspectives and memory theories, cognitive theories also offer interesting viewpoints on the phenomenon of déjà vu. One theory argues that déjà vu stems from a mismatch between the familiarity and novelty of the current experience, in which the brain simultaneously perceives a situation as familiar and new. Another view holds that déjà vu is a result of activating pre-existing cognitive patterns or mental frameworks. These schemas help explain the world, and when triggered by situations similar to past experiences, they can create the illusion of familiarity even in truly novel situations. Moreover, some researchers have drawn analogies between déjà vu and dream recall, suggesting that the experience of déjà vu may involve the brain trying to reconcile current perceptions with fragmented or incomplete memories, similar to the elusive nature of waking dream recall. Together, these cognitive theories reveal the complex process behind déjà vu, emphasizing the role of perception, memory, and cognition in shaping this mysterious phenomenon.
The experience of déjà vu is often associated with a sense of familiarity during unfamiliar situations and may be influenced by various environmental factors. For example, stress and anxiety have been shown to exacerbate déjà vu, possibly due to their effects on cognitive processes and memory retrieval. Meanwhile, sleep-related déjà vu experiences may occur due to disruptions in normal sleep patterns, leading to changes in brain function and memory encoding. Additionally, certain medications, such as those that affect neurotransmitter levels or alter sleep architecture, may contribute to the occurrence or frequency of déjà vu. Understanding these environmental effects can provide valuable insights into the mechanisms of déjà vu and its manifestations in different contexts.
Déjà vu shows interesting patterns across age groups, revealing the role of age and gender in this phenomenon. According to Smitha Bhandari, déjà vu varies by age group, with some studies showing higher rates among younger people, ranging from 15-25 years old. This may be attributed to differences in memory consolidation processes or cognitive function across the lifespan.
Déjà vu remains a fascinating mystery that transcends cultural and demographic boundaries. Psychological, neurological, and cognitive perspectives have provided valuable insights into its mechanisms, suggesting complex interactions between memory processes, attentional mechanisms, and cognitive frameworks. Environmental factors such as stress, sleep disorders, and drug use further influence the experience of déjà vu, while age patterns reveal the role of demographic factors. As our understanding continues to evolve, the feeling of déjà vu will continue to provide avenues for exploring the mysteries of human cognition and consciousness, reminding us of the profound complexity of the human psyche.
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