Glossary
Searchable terminology from accessibility, web standards, and related fields.
6660 terms — page 221 of 333
- Photoparoxysmal Response (PPR, Photosensitive Response)
- An abnormal brain response to flashing lights or patterns, detected through electroencephalogram (EEG) monitoring during intermittent photic stimulation. A photoparoxysmal response indicates photosens…
- Photophobia (Light Sensitivity)
- A genuine physiological sensitivity to bright light, flickering light, or intense visual patterns that causes symptoms such as headaches, migraines, nausea, dizziness, and disorientation. Despite its …
- Photoplethysmography (PPG)
- A non-invasive optical technique used to detect blood volume changes in peripheral circulation, commonly implemented in wearable devices like smartwatches and fitness trackers. PPG sensors use light (…
- Photosensitive epilepsy (PSE, Photosensitivity, Visually-provoked epilepsy)
- A form of epilepsy in which seizures are triggered by visual stimuli such as flashing lights, strobing effects, rapid colour transitions, or high-contrast repeating patterns. It affects approximately …
- Photosensitivity (Photosensitive Epilepsy, PSE)
- A neurological condition in which exposure to flickering light patterns, flashing graphics, or rapid luminance changes triggers physiological responses including seizures, migraines, nausea, dizziness…
- Photosensitivity (Light Sensitivity, Photophobia)
- An abnormal sensitivity to light that can cause discomfort, pain, or visual disturbance. Photosensitivity affects many people with visual impairments and certain neurological conditions including migr…
- Phrase-Based Communication (Phrase-Based AAC, Pre-Stored Phrase Communication)
- An augmentative and alternative communication approach where users select complete pre-composed phrases or sentences rather than constructing messages letter by letter or word by word. Phrase-based sy…
- Physical Accessibility (Physical Access, Architectural Accessibility)
- Physical accessibility refers to the design of buildings, environments, and public spaces so they can be independently used by people with physical disabilities, including those who use mobility aids.…
- Physical Agency (Bodily Agency, Sense of Agency)
- The feeling of control and ownership over physical actions and their effects in the world. In assistive technology contexts, physical agency refers to a users sense of directly controlling objects and…
- Physical Control (Direct Control, Direct Manipulation)
- An interaction paradigm where the user directly manipulates on-screen objects or controls by pointing to them and acting on them, as with a mouse click or touch screen tap. In physical control, the fo…
- Physical Crowdsourcing (Spatial Crowdsourcing, Physical World Crowdsourcing)
- A form of crowdsourcing in which tasks require participants to perform actions in the physical world rather than completing digital tasks online. In an accessibility context, physical crowdsourcing ha…
- Physical Disability (Motor Disability, Physical Impairment)
- A condition that affects a person's physical functioning, mobility, dexterity, or stamina. Physical disabilities include conditions such as paralysis, amputation, muscular dystrophy, cerebral palsy, s…
- Physical Guidance (Hands-On Guidance, Physical Assistance)
- A body movement teaching technique in which an instructor physically moves or positions a student's body to demonstrate correct form, rhythm, or placement. Physical guidance is widely used in teaching…
- Physical Layer Accessibility
- The dimension of VR accessibility concerned with whether users can physically access and operate VR hardware and interaction paradigms. This includes the setup process (putting on head-mounted display…
- Physical Rehabilitation (Physiotherapy, Physical Therapy)
- A therapeutic process aimed at restoring, maintaining, or improving physical function, mobility, and strength through structured exercises and interventions. Physical rehabilitation is essential for p…
- Physical Therapy (Physiotherapy, PT)
- A healthcare profession focused on evaluating and treating physical impairments, functional limitations, and disabilities through movement, exercise, manual therapy, and assistive devices. Physical th…
- Physiological Computing (Biometric Computing, Biosignal-based Computing)
- A computing paradigm that uses real-time physiological signals from the body to inform system responses and adaptations. Common signals include heart rate (via photoplethysmography), skin conductance …
- Physiological Sensing (Biosensing)
- Measuring bodily signals - such as heart rate, galvanic skin response, skin temperature, respiration, or muscle activity - to infer aspects of a user's physical or affective state. Physiological sensi…
- Pico Projection (Pico Projector, Pocket Projector, Mini Projection)
- A compact projection technology that enables small, portable devices to project images and information onto nearby surfaces. In accessibility contexts, pico projection offers an alternative to screen-…
- Pictograms (Pictogram, Picture Symbols, PCS)
- Simplified pictorial symbols that represent concepts, objects, activities, emotions, or places, widely used as a form of augmentative and alternative communication (AAC) and as a visual support for au…