The processing of ambiguous words without context: Semantic activation, inhibition, selection and controlled retrieval in younger and older adults.

Both younger and older adults showed semantic priming benefits when processing dominant meanings and monosemic associates in the Lexical Decision Task.

• 100 older adults (mean age 66.94±4.49) and 75 younger adults (mean age 26.64±5.87) were tested
• The paradigm used a Lexical Decision Task (LDT) with ambiguous and monosemic words
• Priming effects for dominant meanings and monosemic associates were consistent across age groups
• These results indicate preserved early-stage automatic semantic activation with aging

Subordinate meanings and unrelated targets produced slower responses in the Lexical Decision Task, suggesting the involvement of inhibitory mechanisms.

• Slower responses to subordinate meanings and unrelated targets were observed in both age groups
• These effects were consistent across younger and older adults
• The findings indicate that early-stage inhibitory mechanisms are preserved with aging
• The LDT paradigm was adapted in French for this study

Inhibitory effects in early-stage semantic processing were preserved across age groups, indicating no age-related decline in automatic inhibition.

• Results from the LDT showed consistent inhibitory effects for both younger (mean age 26.64±5.87) and older adults (mean age 66.94±4.49)
• Both subordinate meaning suppression and unrelated target interference patterns were similar across age groups
• The authors conclude that 'early-stage activation and inhibition' remain intact with aging

In the Cue-to-Target Association Task, participants were more accurate when associating based on perceptual features than on overall meaning.

• The Cue-to-Target Association Task (CTTAT) was used to evaluate executive semantic processes including selection and controlled retrieval
• The accuracy advantage for perceptual feature-based associations over meaning-based associations was observed across participants
• The CTTAT paradigm was adapted in French

Older adults showed vulnerability in the semantic selection process, particularly in the presence of semantic distractors, while controlled retrieval abilities were preserved.

• Older adults (mean age 66.94±4.49, n=100) demonstrated impaired selection compared to younger adults (mean age 26.64±5.87, n=75)
• The selection vulnerability was especially evident 'in the presence of semantic distractors'
• Controlled retrieval abilities were preserved in older adults
• The findings indicate that 'aging selectively affects semantic selection, whereas activation, early inhibition, and controlled retrieval remain largely intact'

The pattern of results challenges global decline models of cognitive aging by demonstrating selective rather than generalized effects on semantic memory processes.

• Activation, early inhibition, and controlled retrieval were found to be largely intact in older adults
• Only semantic selection showed age-related vulnerability
• The authors state the findings 'challenge global decline models of cognitive aging by showing selective effects on interference control'
• The study provides 'an integrated framework for assessing semantic control across the lifespan'