Older adults are sometimes more resistant to the influence of repetition than younger adults because they have a more vast knowledge base that is unlikely to be swayed when repeatedly presented with information that contradicts what they know to be true.

Pepperdine University

Older and younger adults are influenced by the illusory truth effect to the same degree. However, those with Alzheimer's or other forms of dementia are usually less influenced by repetition.

Age and the Illusory Truth Effect

Brashier, N. M., & Schacter, D. L. (2020). Aging in an Era of Fake News. Current Directions in Psychological Science, 29(3), 316–323. https://doi.org/10.1177/0963721420915872

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