Differential impacts of healthy cognitive aging on directed and random exploration.

Deciding whether to explore unknown opportunities or exploit well-known options is a ubiquitous part of our everyday lives. Extensive work in college students suggests that young people make explore-exploit decisions using a mixture of information seeking and random behavioral variability. Whether, and to what extent, older adults use the same strategies is unknown.

A divisive model of evidence accumulation explains uneven weighting of evidence over time.

Divisive normalization has long been used to account for computations in various neural processes and behaviours. The model proposes that inputs into a neural system are divisively normalized by the system's total activity. More recently, dynamical versions of divisive normalization have been shown to account for how neural activity evolves over time in value-based decision making.

Regulation of evidence accumulation by pupil-linked arousal processes.

Effective decision-making requires integrating evidence over time. For simple perceptual decisions, previous work suggests that humans and animals can integrate evidence over time, but not optimally. This suboptimality could arise from sources including neuronal noise, weighting evidence unequally over time (that is, the 'integration kernel'), previous trial effects and an overall bias.