Facial Emotion Recognition of Sadness Relates to Superior Parietal Cortical Thickness in Mild Cognitive Impairment

Mild cognitive impairment (MCI) is associated with early, regionally selective neurodegenerative changes that may affect socioemotional functioning before atrophy becomes widespread. This study examined whether structural brain alterations in MCI relate to facial emotion recognition performance. Sixty adults (30 MCI, 30 healthy controls), aged 50-86 years, completed neuropsychological testing, the Facial emotion composite Task, and structural MRI. Our results revealed no significant gray matter volume differences between groups. Cortical thickness analyses identified two regions with reduced thickness in MCI: the right superior parietal lobule and the left posterior insula. Results revealed that greater regional volume predicted better sadness recognition in MCI, whereas this association was negative in healthy controls. These findings suggest that early MCI involves selective thinning in association cortices supporting attention and salience processing. The sadness-specific interaction indicates that patients with MCI may draw on structural reserve within the superior parietal lobule to support recognition of subtle negative expressions, highlighting early parietal involvement in socioemotional decline.