What is a Brain-Computer Interface (BCI)?

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From the Guidelines

A Brain-Computer Interface (BCI) is a system that enables direct communication between the brain and external devices, controlled by thoughts, with applications in medicine for individuals with paralysis or neuromuscular disorders. BCIs operate by detecting brain signals through various methods such as electroencephalography (EEG), electrocorticography (ECoG), or implanted electrodes, and then translating these signals into device commands 1. These systems have significant implications in healthcare, especially for people with severe motor impairments, allowing them to control prosthetics, communicate when speech is not possible, or operate assistive devices like wheelchairs. Key aspects of BCIs include:

  • Recording electrical activity from neurons
  • Processing these signals to identify patterns associated with specific thoughts or intentions
  • Converting them into digital commands for devices While the evidence regarding the use of non-invasive brain-computer interfaces to improve upper extremity motor outcomes and activities of daily living is insufficient to recommend for or against, as stated in the 2024 U.S. Department of Veterans Affairs and U.S. Department of Defense clinical practice guidelines 1, the technology holds promise for future medical applications. BCIs can be categorized into non-invasive, which are safer but less precise, and invasive, which offer more accurate signals but involve surgical risks. The ongoing advancement in BCI technology focuses on enhancing signal detection, improving processing algorithms, and developing more user-friendly, wireless systems for both medical and consumer use.

From the Research

Definition of Brain-Computer Interface

  • Brain-Computer Interfaces (BCIs) use brain activity to control external devices, facilitating paralyzed patients to interact with the environment 2, 3, 4.
  • BCIs acquire brain signals, analyze them, and translate them into commands that are relayed to output devices that carry out desired actions 4.
  • The main goal of BCI is to replace or restore useful function to people disabled by neuromuscular disorders such as amyotrophic lateral sclerosis, cerebral palsy, stroke, or spinal cord injury 4.

Techniques Used in BCIs

  • Distinct techniques have been explored to control a BCI, including electroencephalography (EEG) and near-infrared spectroscopy (NIRS) due to their noninvasive nature and low cost 2.
  • Functional near-infrared spectroscopy (fNIRS) has been used to develop BCI systems for communication, particularly for people with severe motor disabilities like ALS 5, 6.
  • Other brain signals, such as intracortical and electrocorticographic signals, have also been used for BCI control 2, 4.

Applications of BCIs

  • BCIs have been used to provide a means of communication for patients with locked-in state (LIS) and completely locked-in state (CLIS) 2, 3.
  • BCIs have also been used for restoration of motor impairment after severe stroke 2.
  • BCIs may also prove useful for rehabilitation after stroke and for other disorders, and could potentially augment the performance of surgeons or other medical professionals 4.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Brain-computer interfaces in medicine.

Mayo Clinic proceedings, 2012

Research

Enhancing Communication for People in Late-Stage ALS Using an fNIRS-Based BCI System.

IEEE transactions on neural systems and rehabilitation engineering : a publication of the IEEE Engineering in Medicine and Biology Society, 2020

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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