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RT can also be operationally defined as “complex,” which involves a reaction to one or more visual stimuli after recognition (cvrRT) of correct stimuli and inhibiting incorrect stimuli 12. RT can be operationally defined as “simple,” which typically involves a non-choice reaction to a visual stimulus (svRT).
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These findings collectively suggest that RT is a useful index of age-related cognitive decline, healthy brain aging, and neurodevelopment. Moreover, studies comparing varied factors and tests of age-related episodic memory deficit implicate age-related decline in processing speed as the main mediator 9– 11. In studies where processing speed was used as a covariate, the age-related variance in various episodic memory measures was reduced or even eliminated 7, 8. Processing speed is an important limiting factor for most aspects of cognition during aging, most notably memory 5, 6. In fact, of the studied demographics, age is the main factor known to influence RT 4. Reaction time (RT), an index of processing speed or efficiency in the central nervous system (CNS) 1, is an essential factor in higher cognitive function 2, 3 and is profoundly affected by age 4. Divergent findings from UKBb MindCrowd included more education being associated with shorter svRTs and a history of smoking with longer svRTs from younger to older ages. (2) Men with the least education were associated with longer cvrRTs comparable to women across all educational attainment levels. Divergent findings from the UK Biobank included (1) a first-degree family history of Alzheimer’s disease (FHAD) was associated with longer cvrRT. Analyses revealed similarities between MindCrowd and the UK Biobank across most results. An identical linear model (LM) was used to assess both cohorts. Similarities between the UK Biobank and MindCrowd were assessed using a subset of MindCrowd (UKBb MindCrowd) selected to mirror the UK Biobank demographics ( n total = 39,795, n women = 29,640, n men = 10,155 ages 40–70 years old, M Age = 56.59, SD Age = 8.16). To complement this work, we evaluated complex visual recognition reaction time (cvrRT) in the UK Biobank ( n total = 158,249 n women = 89,333 n men = 68,916 ages 40–70 years old, M Age = 55.81, SD Age = 7.72). Analysis of svRT revealed education and stroke as potential modifiers of changes in processing speed and memory from younger to older ages ( n total = 75,666, n women = 47,700, n men = 27,966 ages 18–85 years old, mean ( M) Age = 46.54, standard deviation (SD) Age = 18.40).
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svRT and PAL results were combined with 22 survey questions. MindCrowd is a cross-sectional web-based assessment of simple visual (sv) reaction time (RT) and paired-associate learning (PAL). To identify potential factors influencing age-related cognitive decline and disease, we created MindCrowd.