From early childhood to late adulthood: Lifespan trajectories of attention and inhibition

The prefrontal cortex of the human brain supports many executive control abilities. Three of fundamental abilities include: maintaining speed of responding to external stimuli (simple reaction time); maintaining attention for stimuli in the presence of distractors (sustained attention); and refraining automatic behaviours (inhibition). These three cognitive functions are largely supported by different subregions of the prefrontal cortex, which may exhibit differing ageing trajectories over the lifespan. While a broad developmental trajectory is established, current research is largely composed of separate studies focused on discrete age groups performing different cognitive paradigms, making it difficult to draw a comparable lifespan trajectory. The implementation of a same paradigm helps characterise differences in responses across ages, support appropriate inter-trial-interval selection by target age, and provides a normative data for interpretation of future research. Therefore, this cross-sectional analysis sought to identify developmental differences across the human lifespan in simple reaction time, sustained attention (Stay-Go) and inhibition (Go/NoGo). A total of 2,353 participants (5–80 years old) completed the same cognitive battery. Regression models demonstrated polynomial associations between age and reaction time, where performance on all three tasks followed similar trends but with differing slopes. Key inflection points in the models generally occurred in the mid-20s (peak performance and subsequent decline), late 40s (plateau), and early 60s (further decline). Early development slopes were greater for stimuli with longer inter-trial-intervals, which converged in the early 20s. Interaction effects between age and sex were identified for errors on the Go/NoGo task, where males exhibited more errors in early years.