A 25-year cohort study of the prevalence of deja vu, jamais vu and synesthesia phenomena in Rudn university students
M. S. Artemieva, R. Suleimanov, I. Danilin, A. LazukovaIntroduction
Scientific literature from the 19th and 20th centuries indicates that approximately two-thirds of all people reported experiencing déjà vu and various similar states.
Objectives
The aim of this 25-year study was to investigate the prevalence and incidence of deja vu, jamais vu and synesthesia symptoms in modern society.
Methods
Fifth-year medical students of RUDN University aged 22-24 years +/- 2.4 participated in this study annually from 2001 to 2025. A total of 2860 students were included in the study.
Results
The prevalence of déjà vu at the beginning of the observation (2001–2004) was 82% (95% CI: 79–85%), then consistently increased by 2015 reaching 98.5% (95% CI: 97–99%) and remains at this level to this day. For most respondents, déjà vu occurs quite rarely (from 2 to 10 times over many years), mainly in childhood and adolescence.
A consistent increase in the incidence of synesthesia in students was noted, as a stable feature that is not subject to significant changes and persists throughout life, from 12.6% (95% CI: 11-16%) in 2000-2015 to 22.3% (95% CI: 20-25%) in 2016-2025 (χ2 = 41.7, p < 0.001).
The jamais vu phenomenon was relatively rare: in 2001-2017, the frequency was 3% (95% CI: 2-5%), and in 2018-2025. increased to 5% (95% CI: 3–8%) (χ 2 =6.7, p<0.01). Lifetime prevalence of jamais vu remained consistently low – 1–3 cases in 96% of respondents who answered positively.
Conclusions
This study demonstrates a significant increase in the incidence of deja vu, jamais vu and synesthesia over the past 25 years and requires further investigation.
Disclosure of Interest
None Declared