Glossary

Search results

Asynchronous Control(also: Self-Paced Control, Asynchronous BCI)

A mode of interaction with a computer or assistive device where the user can issue commands at any time of their choosing, rather than being constrained to respond within system-defined time windows. In brain-computer interface research, asynchronous control is contrasted with…

Beta Rhythm(also: Beta Wave, Beta Oscillation)

A pattern of electrical brain activity oscillating at approximately 13-30 Hz, commonly recorded over the sensorimotor cortex. Like mu rhythms, beta rhythms are modulated by movement and motor imagery — they are suppressed during movement and show a characteristic post-movement…

Bio-Electrical Signal(also: Biosignal, Bioelectrical Signal, Physiological Signal)

A bio-electrical signal is an electrical potential generated by biological processes in the human body, including muscle contractions (EMG), brain activity (EEG), eye movements (EOG), heart rhythms (ECG), and skin conductance (GSR). In assistive technology, bio-electrical…

Biometric Control(also: Biometric Input, Physiological Control Interface)

The use of measurable biological signals from the human body — such as brain waves (EEG), skin conductance (galvanic skin response), muscle electrical activity (EMG), heart rate, or eye movements — as input channels for controlling computers and assistive technology devices.…

BrainGate(also: BrainGate2)

A long-running multi-site clinical trial program (ClinicalTrials.gov NCT00912041) that evaluates implantable intracortical brain-computer interfaces in people with paralysis from spinal cord injury, ALS, brainstem stroke, and other neurological conditions. Participants receive…

Electroencephalography(also: EEG)

A non-invasive method of recording electrical activity of the brain using electrodes placed on the scalp. In assistive technology, EEG is the primary sensing technology behind brain-computer interfaces (BCIs), which allow people with severe motor impairments such as paralysis or…

Event-Related Potential(also: ERP)

An event-related potential (ERP) is a measured brain response that is the direct result of a specific sensory, cognitive, or motor event. ERPs are extracted from electroencephalography (EEG) recordings by averaging brain signals time-locked to repeated presentations of a…

Functional Near-Infrared Imaging(also: fNIR, fNIRS, Functional Near-Infrared Spectroscopy)

A neuroimaging technique that measures brain activity by detecting changes in oxygenated blood volume using near-infrared light transmitted through the skull. In accessibility contexts, fNIR enables brain-computer interfaces that allow people with severe motor disabilities to…

Imagined Voluntary Movement-Related Potentials(also: IVMRPs, Motor Imagery Potentials)

Electrical brain signals generated when a person imagines performing a voluntary movement without actually executing it. These potentials, detectable via EEG electrodes placed over motor cortex areas, are similar in pattern to the signals produced during actual movement. IVMRPs…

Individual-Technology Fit(also: ITF, User-Technology Match)

A framework for matching individual users with the most appropriate assistive technology based on their personal characteristics and the technology's requirements. In brain-computer interface contexts, ITF considers factors like age, education, caffeine consumption, and video…

Intracortical BCI(also: iBCI, Intracortical Brain-Computer Interface)

A brain-computer interface that records neural activity directly from inside the cerebral cortex, typically using surgically implanted microelectrode arrays such as the Utah array. Compared with non-invasive EEG-based BCIs, intracortical BCIs offer dramatically higher…

Learning Vector Quantization(also: LVQ)

A supervised machine learning algorithm used for pattern classification, commonly applied in brain-computer interface systems to classify EEG signals. LVQ works by creating a set of reference vectors (codebook) that represent decision boundaries between different classes of…

Microelectrode Array(also: Utah Array, MEA)

A small grid of fine recording electrodes (typically 96 silicon shanks in a 4mm x 4mm Utah array) surgically implanted into the cerebral cortex to record the electrical activity of individual neurons and small neural populations. Microelectrode arrays are the sensing front-end…

Motor Cortex(also: Primary Motor Cortex, M1)

The region of the cerebral cortex responsible for planning, controlling, and executing voluntary movements. Located in the frontal lobe along the precentral gyrus, the motor cortex is organised somatotopically — different areas control different body parts. In brain-computer…

Mu Rhythm(also: Mu Wave, Mu Oscillation)

A pattern of electrical brain activity oscillating at approximately 8-12 Hz, recorded over the sensorimotor cortex. Mu rhythms are suppressed (desynchronised) when a person performs or imagines performing a movement, a phenomenon known as event-related desynchronisation. In…

Neural Control(also: Neural Interface, Neural Signal Input)

A method of computer interaction where users modulate their brain signals, detected through electroencephalography (EEG) or other neural monitoring technologies, to generate input commands. Neural control users can typically produce a small number of distinct signals by…

Neural Prosthetics(also: Neuroprosthetics, Neural Prostheses)

Devices that interface directly with the nervous system to restore or supplement lost sensory, motor, or cognitive functions. Neural prosthetics can be input devices (reading neural signals to control external equipment, as in brain-computer interfaces) or output devices…

Neurotrophic Electrode(also: Neurotrophic Brain Electrode, Cone Electrode)

A type of implantable brain electrode designed for long-term, stable recording of neural signals. Unlike conventional electrodes that sit on the brain surface or are inserted as rigid probes, a neurotrophic electrode consists of a hollow glass cone coated with neurotrophic…

Nontraditional Assistive Technologies(also: NTATs, Nontraditional Input Technologies)

Input technologies that use physiological signals rather than physical movement to control computers, providing access for people who cannot use traditional devices like keyboards, mice, or even eye-tracking systems. NTATs include brain-computer interfaces (using EEG or fNIR),…

P300(also: P3, P300 Component, P3b)

The P300 is an event-related potential (ERP) component — a positive voltage deflection in EEG brain signals that peaks approximately 300 milliseconds after a person perceives a rare or task-relevant stimulus among frequent non-target stimuli. It is named for its polarity…

Sensorimotor Rhythm(also: SMR, Sensorimotor Cortical Rhythm)

Oscillatory electrical brain activity recorded over the sensorimotor cortex, the brain region responsible for planning and executing voluntary movements. Sensorimotor rhythms include mu rhythms (8-12 Hz) and beta rhythms (18-26 Hz), which change in amplitude when a person…

Slow Cortical Potential(also: SCP, Slow Cortical Potentials)

Gradual voltage shifts in the electrical activity of the brain, occurring over periods of several hundred milliseconds to several seconds. Slow cortical potentials reflect changes in the overall excitability level of cortical neural networks — negative shifts indicate increased…

Speech Neuroprosthesis(also: Speech BCI, Speech Brain-Computer Interface)

A brain-computer interface that decodes neural activity associated with attempted or imagined speech and converts it into text, synthesized voice, or both. Speech neuroprostheses are designed for people with anarthria or severe dysarthria from ALS, brainstem stroke, locked-in…

Visual Evoked Potential(also: VEP, Visually Evoked Response, VERP)

A visual evoked potential (VEP) is an electrical signal generated by the brain's visual cortex in response to a visual stimulus, typically a flash of light or a pattern change. VEPs are measured using electrodes placed over the occipital lobe and extracted from background EEG…

24 results.