Musical auditory feedback BCI: clinical pilot study of the Encephalophone

TL;DR

A new brain-computer interface called the Encephalophone helps people with severe motor disabilities create music using brain signals, improving their ability to express themselves.

Contribution

The study introduces a novel auditory BCI system that enables real-time musical expression without physical movement.

Findings

Subjects improved pitch-matching accuracy by 15.6 percentage points and increased hits by 58.7% over three sessions.

All participants scored above random probability in pitch-matching tasks, indicating meaningful performance improvement.

Participants reported positive experiences with self-expression, enjoyment, and control during music improvisation.

Abstract

Therapeutic strategies for patients with severe acquired motor disability are relatively limited and show variable efficacy. Innovative technologies such as brain-computer interfaces (BCIs) have been developed recently that might benefit certain types of patients.

Here, we tested a previously described auditory BCI, the Encephalophone, which may offer new options to improve quality of life and function. Eleven subjects with acquired moderate to severe motor disability, who had lost their ability to express themselves musically, were enrolled and 10 completed a clinical pilot study of the hands-free Encephalophone brain-computer interface (BCI). Subjects were briefly instructed on the use of the Encephalophone BCI, which uses EEG measured motor imagery to allow users to generate musical notes in real time without requiring movement. Subjects then underwent a pitch-matching task, a measure of accuracy, to attempt to match a given target pitch 3 times within 10 s. They were allowed free play, where they could improvise music over a backing track. After 2–3 songs - approximately 10 min - of freely improvised playing, subjects repeated the pitch-matching task. There were 3 sessions of testing and free play per subject, within 2 weeks, with at least 1 day separating sessions.

All subjects, on average, improved their pitch-matching accuracy by 15.6 percentage points and increased their number of hits by 58.7% over the 3 sessions, with all subjects scoring accuracy percentages significantly above random probability (19.05%). A subjective self-reporting survey of ratings of such factors as a feeling of expressing oneself, enjoyment, discomfort, and feeling of control showed a generally favorable response.

We suggest that this training approach using an auditory BCI may provide an innovative solution to challenges in recovery from motor disability.

https://research.providence.org/clinical-research, Swedish Health Services #: STUDY2017000301.

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