What matters in making demand-based decisions: Time alone or difficulty too?

Abstract

Which task is easier, doing arithmetic problems of specified form for some specified duration, or carrying a bucket of specified weight over some specified distance? If it is possible to choose between the “more cognitive” task and the “more physical” task, how are the difficulty levels of the tasks compared? We conducted two experiments in which participants chose the easier of two tasks, one that involved solving addition or multiplication problems (Experiment 1) or addition problems with different numbers of addends (Experiment 2) for varying amounts of time (in both experiments), and one that involved carrying a bucket of different weights over a fixed distance (in both experiments). We found that the probability of choosing to do the bucket task was higher when the bucket was empty than when it was weighted, and increased when the cognitive task was harder and its duration grew. We could account for the choice probabilities by mapping the independent variables onto one abstract variable, Φ. The functional identity of Φ remains to be determined. It could be interpreted as an inferred effort variable, subjective duration, or an abstract, amodal common code for difficulty.

Is task switching avoided to save effort or time? Shorter intertrial durations following task switches increase the willingness to switch tasks.

“…As predicted, participants switched tasks more often in blocks where task switches were associated with (relatively) lower temporal costs. This finding is consistent with previous studies showing that the duration of a given action represents a cost factor in decision making (Janczyk et al, 2022;Potts et al, 2018).…”

Switching between different cognitive strategies induces switch costs as evidenced by switches between manual and mental object rotation

“…The underlying idea is that human prob-Switching Cognitive Mechanisms lem solvers might be especially willing to avoid cognitive effort (Kool et al, 2010). However, it has been shown that for voluntary task switches, physical costs factor in as well (Janczyk et al, 2022;Potts et al, 2018). Physical switch costs are present to some degree in the present paradigm (manual rotation necessitates pressing a key that needs preparation) but are likely more pronounced in more physically engaging situations like, for example, when walking to a computer to gain access to a CM (compare Storm et al, 2017).…”

Policy abstraction as a predictor of cognitive effort avoidance.

“…Other task structures might place the weight on attentional or other demands for task optimization. Furthermore, the subjective feeling of effort, as distinct from effort avoidance, may likewise derive from multiple task features ranging from task performance to cognitive or physical task difficulty and may depend on situational factors (Janczyk et al, 2022). Future studies should verify the contribution of multiple factors on effort costs and directly test the effect of task context and structure on the determinants of effort avoidance.…”