What is a brain-computer interface (BCI)?

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From the Guidelines

A brain-computer interface (BCI) is a system that enables people to control devices with their thoughts, bypassing traditional motor pathways, and has the potential to significantly improve the quality of life for individuals with severe motor disabilities.

Definition and Function

A BCI is a technology that establishes a direct communication pathway between the brain and an external device, allowing signals from the brain to control computers, prosthetic limbs, or other machines without requiring normal neuromuscular pathways.

Key Components

BCIs work by detecting brain activity through methods such as electroencephalography (EEG), which records electrical signals from the scalp, or more invasive techniques like electrocorticography (ECoG) or implanted electrodes that capture neural signals directly from brain tissue.

Applications and Benefits

These signals are then processed by algorithms that translate them into commands for external devices. BCIs have significant applications in helping people with paralysis, locked-in syndrome, or other severe motor disabilities to communicate and interact with their environment.

Current State and Future Directions

The technology is advancing rapidly, with current systems allowing users to move cursors, type messages, control robotic limbs, and even restore limited sensory feedback. While non-invasive BCIs are safer but less precise, invasive BCIs offer greater accuracy but involve surgical risks.

Importance of Proper Assessment and Training

As noted in the study on prescribing assistive-technology systems 1, proper assessment and training are crucial for the successful use of any assistive device, including BCIs. The study emphasizes the importance of an interdisciplinary team approach in selecting and implementing assistive devices, considering factors such as the individual's current and future language needs, motor abilities, cognitive levels, and environmental issues.

Conclusion is not allowed, so the answer just ends here.

From the Research

Definition of Brain-Computer Interface

  • A brain-computer interface (BCI) is a system that acquires brain signals, analyzes them, and translates them into commands that are relayed to output devices to carry out desired actions 2.
  • BCIs do not use normal neuromuscular output pathways and are designed to replace or restore useful function to people disabled by neuromuscular disorders such as amyotrophic lateral sclerosis, cerebral palsy, stroke, or spinal cord injury 2.

Functionality of Brain-Computer Interface

  • BCIs can use various brain signals, including electroencephalographic, intracortical, and electrocorticographic signals, to control devices such as cursors, robotic arms, prostheses, and wheelchairs 2.
  • BCIs may also be useful for rehabilitation after stroke and for other disorders, and could potentially augment the performance of surgeons or other medical professionals 2.

Applications of Brain-Computer Interface

  • BCIs have been used to restore communication to people severely disabled by amyotrophic lateral sclerosis (ALS) or other disorders 3, 4.
  • Research has shown that most people severely disabled by ALS can use a visual P300-based BCI for communication, but visual impairment can be a significant obstacle 3.
  • BCIs have also been used to improve the quality of life of patients with ALS in the locked-in state (LIS) and the completely locked-in state (CLIS) 5.

Development and Implementation of Brain-Computer Interface

  • The development of BCIs requires advances in three crucial areas: signal-acquisition hardware, validation of BCI systems in long-term studies, and improvement of the day-to-day and moment-to-moment reliability of BCI performance 2.
  • Researchers, clinicians, and patients must become partners in the development and implementation of BCI technology to make it useful to people with ALS in their daily lives 4.
  • The acceptance of BCIs by patients with ALS and their caregivers is influenced by factors such as behavioral impairment and perceived performance at controlling the device 6.

References

Guideline

Guideline Directed Topic Overview

Dr.Oracle Medical Advisory Board & Editors, 2025

Research

Brain-computer interfaces in medicine.

Mayo Clinic proceedings, 2012

Research

Brain-computer interface (BCI) evaluation in people with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis & frontotemporal degeneration, 2014

Research

Acceptance of brain-computer interfaces in amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis & frontotemporal degeneration, 2015

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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