# Physical effort and task errors influence the choice for cognitive offloading

## TL;DR

People consider both physical and mental effort when choosing problem-solving strategies, and errors lead to different reactions depending on the method used.

## Contribution

The study shows that physical and mental effort influence strategy choice and that error reactions differ based on the method used.

## Key findings

- Both physical and mental effort affect the choice between mental and manual rotation strategies.
- Error-induced strategy switches were more common after mental than manual rotation errors.
- Error reactions differ qualitatively depending on whether the error was made using mental or physical means.

## Abstract

Minimizing effort is a principle widely accepted to govern human behavior. We revisited this principle in an extended rotation paradigm. Participants freely chose to solve an object comparison task by either mental or manual rotation of one of two simultaneously presented objects. We manipulated the required force of manual rotation, stimulus complexity, as well as the angular mismatch between both objects, while carefully eliminating confounds of physical effort with time. Our study revealed that both physical and mental effort affect strategy choice. Additionally, strategy choice in a certain trial was influenced by error commissions in the previous trial. These error-induced strategy switches were asymmetric: participants were more inclined to switch following mental than manual rotation errors. Our results suggest that human reactions to error commission when using external tools may differ in a qualitative manner from reactions to error commission during mental endeavors. Theoretical implications are discussed especially in the context of the entanglement of physical effort and time.

Humans possess the ability to solve problems using either mainly mental or physical resources. For example, objects can be rotated in the mind or physically. Here, we show that when comparing the effort associated with both means, they are both considered for decision making. Furthermore, making a mistake seems to evoke different reactions depending on the means with which the error was made. Considering such different costs and benefits is vital for both designing and working in tech-infused environments that support problem solving.

The online version contains supplementary material available at 10.1007/s00426-025-02186-1.