Researchers at the University of Madrid studied the question and they say it’s not an illusion:
The ‘continuity of the self’—the capacity for self-awareness and self-recognition— remains stable whereas other components such as physical aspects, physiological processes and even attitudes, beliefs and values are more liable to change.
Even components such as personality traits tend to change slightly over the years, but “the sense of being oneself is preserved, improving our understanding of human nature,” according to Rubiales. – University of Madrid (Ucm), “Are We the Same Person Throughout Our Lives? In Essence, Yes” at Neuroscience News (November 28, 2020)News, “Do we really remain the same person throughout our lives?” at Mind Matters News
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