Revisiting Embodiment for Brain-Computer Interfaces

TL;DR

This paper reviews the role of embodiment in brain-computer interfaces, arguing that cognition's integration with the body influences BCI design and evaluation, challenging traditional views that prioritize bodily movements.

Contribution

It offers a nuanced perspective on embodiment in BCI research, emphasizing the importance of neural and body integration rather than body movements alone.

Findings

Embodiment should not favor body movements over brain signals.

Body-grounded explanations can improve BCI performance understanding.

Embodiment insights can inform BCI design and evaluation.

Abstract

Researchers increasingly explore deploying brain-computer interfaces (BCIs) for able-bodied users, with the motivation of accessing mental states more directly than allowed by existing body-mediated interaction. This motivation seems to contradict the long-standing HCI emphasis on embodiment, namely the general claim that the body is crucial for cognition. This paper addresses this apparent contradiction through a review of insights from embodied cognition and interaction. We first critically examine the recent interest in BCIs and identify the extent cognition in the brain is integrated with the wider body as a central concern for research. We then define the implications of an integrated view of cognition for interface design and evaluation. A counterintuitive conclusion we draw is that embodiment per se should not imply a preference for body movements over brain signals. Yet it can nevertheless guide research by 1) providing body-grounded explanations for BCI performance, 2) proposing evaluation considerations that are neglected in modular views of cognition, and 3) through the direct transfer of its design insights to BCIs. We finally reflect on HCI's understanding of embodiment and identify the neural dimension of embodiment as hitherto overlooked.