The role of cognitive aging and task complexity in exploratory behavior
In most decision-making situations across the entire life span, people typically do not enjoy access to summarized information about risky options. Instead, they may search for information and learn about environmental contingencies – thus making decisions from experience. Aging is associated with notable deficits in learning and memory – but do these translate into poorer decisions from experience? To address this question, we conducted three studies that used a sampling paradigm to investigate younger (M = 24 years) and older (M = 71 years) adults' decisions from experience.
In Study 1 participants made 12 decisions between pairs of payoff distributions in the lab. Study 2 implemented the same paradigm using portable devices, collecting 84 decisions per individual over a week. Study 3 extended the sampling paradigm by asking participants to make 12 decisions between two, four, and eight payoff distributions (in the lab). The figure below shows the implementation of the sampling paradigm on iPads (with two choice options per decision problem), as implemented in Study 2.
Sampling paradigm implemented on iPad, showing how a person explores two choice options and then makes a final decision.
Surprisingly, the behavioral results suggest that younger and older adults are relatively similar in how they search and what they choose when facing two payoff distributions (Studies 1 and 2). A computational modeling analysis on the level of individual participants showed that a simple delta-rule learning model best described the learning processes of most participants. That is, to the extent that ongoing updating processes (as described by the delta-rule learning model) unfold relatively automatically and effortlessly, older adults may be liberated from the detrimental consequences of cognitive aging in the case of decisions from experience with few decision options. However, with an increasing number of payoff distributions – either 2, 4, or 8 in Study 3 – age differences emerged. The figure below illustrates search effort as a function of the number of choice options in a decision problem.
Exploratory behavior of participants in Study 3, separately for younger and older adults, and as a function of whether choice set sizes were presented in increasing or decreasing order.
To what extent do cognitive abilities, in particular fluid intelligence, matter for search in decisions from eperience? As shown in the figure below, fluid intelligence was only weakly associated with search effort in conditions involving decisions between two options. However, the correlation between fluid intelligence and search was larger in conditions involving more than two options. This effect was even more pronounced for older adults in decision problems with a large choice set size.
Relationship between fluid intelligence and search in the sampling paradigm, seperately for younger and older adults, and for different choice set sizes.
In sum, when people have to learn about decision options in real life, older adults may not necessarily perform worse than younger adults – despite substantial deficits in fluid cognitive abilities. Only when the choice environment is complex (e.g., when there are many decision options), reductions in exploratory behavior, and thus potentially also in choice performance, have to expected in older adults.
Frey, R., Mata, R., & Hertwig, R. (2015). The role of cognitive abilities in decisions from experience: Age differences emerge as a function of choice set size. Cognition, 142, 60-80. doi:10.1016/j.cognition.2015.05.004
Mamerow, L., Frey, R., & Mata, R. (2016). Risk taking across the life span: A comparison of self-report and behavioral measures of risk taking. Psychology and Aging, 31, 711-723. doi:10.1037/pag0000124