Self-Determination Theory and Assistive Technologies: The Role of Competence and Interface Control Modality on Performance and Motivation

Abstract

Spinal cord injury and disorder (SCI/D) patients suffer great physical limitations, causing harm to their psychosocial well-being through limited independence. Environmental control units (ECU) are interactive assistive devices created to aid SCI/D patients foster independence by integrating technologies and varying control methods. One key issue identified by end-users is a lack of training for operating the interface, which puts them at risk of errors and frustration with the ECU. Motivation theory can address and reduce frustration related to interfaces by focusing on facilitating user goals. Self-determination theory (SDT) supports goal-attainment by increasing intrinsic motivation through the satisfaction of basic psychological needs. Through the implementation of training, the basic psychological need of competence can be satisfied. This study therefore investigates the effects of training and different control methods on ECU users’ performance (efficiency and speed) and basic psychological need satisfaction (specifically for competence). This study also investigates trial effects in order to verify the validity of any performance or satisfaction-based differences observed. Results indicated that effects from training and different control methods were not significant. However, trial effects were found to be significant, indicating participants overcame the learning curve of using the ECU through subsequent trials, regardless of training or control method conditions. This result provides critical insights for the design and implementation of direct and indirect control modalities for use with ECUs.