UC Riverside

The aim of the dissertation is to investigate how people trade off between expending motor effort and memorization effort when visually exploring in different directions to gather information. Specifically, Chapter 2 studied how the motor effort of eye-head-body movements and memorization difficulty affected the motor-memory trade-off in a copying task. Chapter 3 studied how people adjusted the motor-memory trade-off after repeated practice with the task. Lastly, Chapter 4 studied whether inducing people to test a different strategy led to discovery and later adoption of a more efficient strategy. Each chapter examined both the copying strategies (i.e. the trade-off between using more motor effort versus more memory) and the eye-head-body coordination underlying the task. Results showed that participants expended more motor effort when the eye-head-body movements to make gaze shifts were less effortful and when the information was difficult to remember (Chapter2); participants used more memory after repeated practice with the task (Chapter 3); exposing participants to test a different strategy led them to adopt a memory-based strategy (Chapter 4). Overall, participants coordinated their eyes, head, and body differently according to the task conditions such as angle and external restriction. They also changed the eye-head-body coordination to decrease total motor cost over the course of doing the task. The findings suggested that people are adaptive in trading off between motor effort and use of memory.