Quantum mechanics

Engineering

Neuroscience

Control engineering

Actuator

Computer science

Haptic technology

Stimulus (psychology)

Physics

Simulation

Psychology

Psychotherapist

Leverage (statistics)

Artificial intelligence

Visual feedback

Action (physics)

Sense of agency

Human–computer interaction

Feedback control

We enable preemptive force-feedback systems to speed up human reaction time without fully compromising the user's sense of agency. Typically these interfaces actuate by means of electrical muscle stimulation (EMS) or mechanical actuators; they preemptively move the user to perform a task, such as to improve movement performance (e.g., EMS-assisted drumming). Unfortunately, when using preemptive force-feedback users do not feel in control and loose their sense of agency. We address this by actuating the user's body, using EMS, within a particular time window (160 ms after visual stimulus), which we found to speed up reaction time by 80 ms in our first study. With this preemptive timing, when the user and system move congruently, the user feels that they initiated the motion, yet their reaction time is faster than usual. As our second study demonstrated, this particular timing significantly increased agency when compared to the current practice in EMS-based devices. We conclude by illustrating, using examples from the HCI literature, how to leverage our findings to provide more agency to automated haptic interfaces.

Preemptive Action