Clinical Manifestations.

Area of Science:

• Neuroscience
• Cognitive Psychology
• Gerontology

Background:

• Verbal memory impairment is a key characteristic of Alzheimer's disease (AD), impacting daily activities.
• Traditional memory assessments use overall scores, but the Item-Specific Deficit Approach (ISDA) offers a more detailed analysis of encoding, consolidation, and retrieval.
• Understanding these memory subprocesses is crucial for predicting functional decline in neurodegenerative conditions.

Purpose of the Study:

• To investigate the predictive utility of the ISDA in assessing verbal memory components (encoding, consolidation, retrieval).
• To determine how these specific memory deficits relate to everyday functioning in individuals with mild cognitive impairment (MCI) and AD.

Main Methods:

• Participants included 58 healthy controls (HC), 65 individuals with MCI, and 18 with AD.
• Verbal memory was assessed using the California Verbal Learning Test-II (CVLT-II).
• The ISDA was applied to CVLT-II data to derive encoding, consolidation, and retrieval deficit indices.
• Everyday functioning was measured using the Everyday Cognition Scales (Ecog).

Main Results:

• In both MCI and AD groups, deficits in encoding and consolidation significantly predicted everyday memory and organizational executive functioning.
• In the AD group specifically, encoding and consolidation deficits also predicted everyday visual-spatial abilities and overall everyday cognition.

Conclusions:

• The ISDA is a valuable, psychometrically sound tool for predicting everyday functioning in individuals with MCI and AD.
• Impaired encoding and consolidation are critical indicators of functional difficulties, particularly in memory and executive functions.
• These findings underscore the importance of assessing specific memory components for accurate diagnosis and functional evaluation in cognitive decline.