Slightly Stretching Your Arm's Reach May Improve VR Interaction: The Optimal Interaction Zone in a Memory Task

This study investigates how interaction methods and spatial distance affect user performance and experience in virtual reality (VR) tasks. We compared the Go-Go technique with ray-based Laser selection across eight target distances (0.67× to 4× arm length) in a memory task to identify distance ranges that minimize motor and cognitive demands and support working memory. Results with 41 participants revealed a trade-off: Go-Go enhanced embodiment, while Laser yielded higher efficiency and lower workload. This trade-off was distance-dependent: Go-Go performed best at 1.2×-1.4×, and Laser at 1.4×-2.2×. Our results offer practical design guidelines for adaptive, distance-aware VR systems that align performance and subjective experience.