Age-related increases in Stroop interference are not best explained by a single global inhibitory deficit; rather, older adults showed greater semantic and response-level conflict than younger adults, whereas task conflict remained comparable across age groups.
Key Findings
Results
Older adults showed larger response conflict than younger adults in the low-cognitive-control Stroop paradigm.
Response conflict was measured by comparing response-set incongruent color words to non-response-set incongruent color words.
The paradigm used a manual color-identification task specifically designed to amplify conflict effects by reducing cognitive control over word processing.
This finding indicates that older adults are disproportionately affected by conflict arising at the response selection stage.
Results
Older adults showed modest age-related increases in both components of semantic conflict (semantic relevance and semantic relatedness).
Semantic relevance was dissociated from semantic relatedness within the single paradigm using neutral shapes, neutral words, color-associated words, and incongruent color words.
The age-related differences in semantic conflict were described as 'modest' relative to the larger effect observed for response conflict.
This suggests that semantic-level processing differences between age groups exist but are smaller in magnitude than response-level differences.
Results
Task conflict did not differ between younger and older adults.
Task conflict was isolated by comparing neutral word conditions to neutral shape conditions within the paradigm.
The absence of an age-related difference in task conflict was a key dissociation from the pattern observed for semantic and response conflict.
This finding argues against a single, global inhibitory deficit account of cognitive aging.
Methods
A low-cognitive-control Stroop paradigm was used to dissociate task conflict, semantic conflict, and response conflict within a single experimental design.
Participants completed a manual color-identification task including five stimulus types: neutral shapes, neutral words, color-associated words, non-response-set incongruent color words, and response-set incongruent color words.
The paradigm was specifically designed to amplify conflict effects by reducing top-down cognitive control over word processing.
The manual-response format and reduced-control conditions were chosen to distinguish this approach from standard Stroop paradigms.
Both younger and older adults participated, allowing direct age-group comparisons across all three conflict types.
Discussion
The pattern of results is consistent with a fine-grained, multi-component account of cognitive control in aging rather than a unitary inhibitory deficit.
The dissociation between preserved task conflict and increased response and semantic conflict in older adults challenges broad inhibitory deficit theories of cognitive aging.
The authors conclude that 'aging may affect some forms of interference more than others.'
The findings motivate future research examining how specific conflict processes relate to functioning in distracting everyday situations.
The authors situate these results in the context of everyday demands such as 'following a conversation in a distracting environment.'
What This Means
This research suggests that the cognitive slowdowns and errors that older adults experience in mentally demanding situations are not simply due to a general weakening of the brain's ability to suppress distractions. Using a specially designed version of the classic Stroop task — where people must identify the color of ink while ignoring the meaning of color words printed in that ink — the researchers found that older adults struggled more than younger adults specifically when the word's meaning directly competed with the correct response (response conflict) and, to a lesser extent, when the word was semantically related to color (semantic conflict). However, older adults performed just as well as younger adults when the basic challenge was simply having to do a color task while ignoring that stimuli were words at all (task conflict).
This distinction matters because it shows that cognitive aging does not cause a blanket decline in all forms of mental interference control. Instead, certain specific stages of processing — particularly those involving selecting among competing response options — appear to be more vulnerable to aging than others. The study used a carefully structured set of stimuli (shapes, unrelated words, color-associated words, and two types of color-word conflicts) to tease apart these different sources of interference within a single experiment.
This research suggests that future work should investigate how these specific conflict types map onto real-world difficulties older adults face, such as staying focused in noisy or distracting environments. Understanding which conflict-resolution mechanisms are most affected by aging could eventually help inform more targeted cognitive training or support strategies for older adults.
Keha E, Augustinova M, Ferrand L, Kalanthroff E. (2026). Dissociating task, semantic, and response conflict in cognitive aging: evidence from a low-cognitive control Stroop paradigm.. Psychological research. https://doi.org/10.1007/s00426-026-02399-y