Sequential processing in young and older adults in the equiprobable auditory Go/NoGo task

Abstract

Objective: We recently proposed a sequential processing schema for the equiprobable auditory Go/NoGo task, based on a principal components analysis (PCA) of event-related potentials (ERPs) from a university student sample. Here we sought to replicate the schema, and use it to explore processing in well-functioning older adults.

Methods: We compared behavioural responding and ERPs of 20 independent-living older adults (Mage=68.2years) to data from a sex- and handedness-matched group of university students (Mage=20.4years). ERPs had substantial latency differences between the groups, and hence were subjected to separate group temporal PCAs.

Results: Component latencies were systematically increased in the older group by some 26%, with no significant increase in RT or error rates. Despite some differences in their identified components, each group displayed differential component responsivity to Go versus NoGo; this was reduced in the older participants.

Conclusion: The results support our processing schema, and provide insight into the processing stages in well-functioning older adults.

Significance: Understanding the perceptual and cognitive processing stages in normal ageing is a pre-requisite for research on mild cognitive impairment and dementia. This study may also provide a simple paradigm and schema suitable for further exploration of functionality in ageing.

Keywords: Ageing; Auditory equiprobable Go/NoGo task; Event-related potentials (ERPs); Principal components analysis (PCA); Sequential processing schema.