Memorability of photographs in subjective cognitive decline and mild cognitive impairment: Implications for cognitive assessment.

Impaired long-term memory is a defining feature of mild cognitive impairment (MCI). We tested whether this impairment is item specific, limited to some memoranda, whereas some remain consistently memorable. We conducted item-based analyses of long-term visual recognition memory. Three hundred ninety-four participants (healthy controls, subjective cognitive decline [SCD], and MCI) in the multicentric DZNE-Longitudinal Cognitive Impairment and Dementia Study (DELCODE) were tested with images from a pool of 835 photographs. We observed consistent memorability for images in healthy controls, SCD, and MCI, predictable by a neural network trained on another healthy sample. Looking at memorability differences between groups, we identified images that could successfully categorize group membership with higher success and a substantial image reduction than the original image set. Individuals with SCD and MCI show consistent memorability for specific items, while other items show significant diagnosticity. Certain stimulus features could optimize diagnostic assessment, while others could support memory.