Effects of movement specific reinvestment on upper-limb prosthesis control and user experience

Purpose: Prosthetic hand devices are frequently abandoned as they are difficult to use and impose high mental workload upon users. However, researchers are yet to establish whether personality factors might contribute to these negative prosthetic hand experiences. In this study, we examined whether key prosthetic hand outcome measures were associated with the trait inclination for conscious movement control – a phenomenon termed “reinvestment” that can impair motor performance and deplete cognitive resources. Materials and methods: A cross-sectional survey was distributed online to a sample of upper-limb prosthesis users. Thirty-six respondents answered demographic questions and completed three questionnaires related to device satisfaction, trait reinvestment, and mental workload. Results: Correlational analysis revealed that a greater propensity for movement specific reinvestment was associated with lower prosthesis satisfaction, higher mental workload, and lower levels of perceived device predictability. It was also found that mental workload mediated the relationship between reinvestment tendencies and both device satisfaction and hours of prosthesis use per day. Conclusions: This study provides the first evidence that trait reinvestment is negatively implicated in the control and satisfaction of prosthetic hand use. We suggest that training interventions for prosthetic hand use should aim to limit conscious control of movements.