Introduction to Agency and Electrical Muscle Stimulation
The use of electrical muscle stimulation (EMS) in interactive devices can often evoke laughter from volunteers on account of the unnatural sensation of a machine controlling their body. This disruption within the sense of agency, or the sensation of being in charge of one’s actions, could potentially interfere with the technology’s ability to enhance learning and enhance virtual reality experiences.
Exploring the Concept of Agency
Asst. Prof. Pedro Lopes, who has been studying devices through a human-computer interface lens, became desirous about whether agency might be measured, controlled, or restored in the course of the use of EMS devices. He, along along with his collaborators, has been investigating this idea using various methods, including pitching machines and fMRI brain scanners. Lopes’ research began with an easy query: Does EMS all the time must feel unnatural, or is there a solution to make it feel more in tune with one’s own volition?
The Initial Experiment
The research on agency began with a demo where volunteers were asked to catch a marker dropped by one other person at short range using EMS. The results showed that the majority participants attributed their motion to the machine, not their very own reflexes. However, a small minority of participants disagreed, saying that the EMS must not have been on because they caught the marker unassisted. This unexpected end result inspired further experimentation.
Timing and Agency
Lopes, along along with his colleagues Jun Nishida and Shunichi Kasahara, conducted an experiment where they adjusted the timing of when EMS triggered a user to perform a selected task. They found that there’s a window of time where it becomes difficult for users to tell apart between their very own actions and people generated by EMS. If the stimulation occurs too early, it feels artificial, but when it occurs just before the user would normally act, they may not even notice that the EMS was involved.
Measuring Agency within the Brain
In a recent study, Lopes used fMRI brain scanners to measure the electrical activity within the brain during a virtual reality task. Participants were asked to the touch a virtual box and received several types of feedback, including visual, vibration, and muscle stimulation. The results showed that when the feedback was mismatched, the brain’s electrical activity modified, indicating a decrease within the sense of agency. This suggests that the brain has a built-in detector for measuring agency, even when the user just isn’t consciously aware of it.
Brain Areas and Agency
Lopes collaborated with neuroscientists to make use of EMS and fMRI to look for brain areas that distinguish between self-generated and externally-generated motion. The study found that the posterior insular cortex responds strongly to the touch during self-generated motion but not during EMS stimulation. This suggests that there’s a mechanism related to touch that checks for agency and regulates inputs, allowing us to quickly switch between different tasks.
Conclusion
The research on agency and EMS has the potential to guide engineers in designing more practical devices. By monitoring a user’s brain activity, developers can determine whether a virtual reality experience is perceived as real and fine-tune the software accordingly. Preserving a way of agency within the user could also make EMS more practical at teaching physical actions, comparable to improving a tennis stroke or playing an instrument. Ultimately, understanding agency and find out how to restore it during EMS use may lead to more realistic and fascinating virtual reality experiences.
