— Ch. 1 · Defining Interaction Channels —
Modality (human–computer interaction).
~3 min read · Ch. 1 of 6
A single independent channel of input or output defines a modality in human, computer interaction. Such channels differ based on sensory nature like vision versus audition. They also vary by processing type such as text compared to image. A system becomes unimodal if it implements only one modality. It turns multimodal when more than one exists. Overlapping modalities appear when multiple options serve some tasks. Redundant modalities occur when several handle the same task simultaneously. These combinations can convey information more effectively through complementary methods. The field generally divides into computer, human and human, computer forms.
Sensory Output Technologies
Computers utilize wide ranging technologies to communicate with humans. Common modalities include vision through computer graphics on screens. Audition delivers various audio outputs to listeners. Tactition provides vibrations or other movement sensations. Uncommon modalities exist including gustation for taste and olfaction for smell. Thermoception handles heat while nociception manages pain signals. Equilibrioception tracks balance within the user experience. Seeing and hearing transmit information at higher speeds than others. Vision reaches 250 to 300 words per minute according to research. Hearing achieves 150 to 160 words per minute in similar studies. Tactition via refreshable Braille displays averages 125 words per minute. Smartphone and game controller vibrations represent common tactile feedback today.Input Device Classifications
Computers receive information from humans using diverse input devices and sensors. Simple modalities include keyboards, pointing devices, and touchscreens. Complex modalities encompass computer vision, speech recognition, motion tracking, and orientation sensing. Certain modalities provide richer interaction depending on specific contexts. Having options allows for more robust system implementations. Smartphones have increased public comfort with complex modalities significantly. Motion and orientation track movement in smartphone mapping applications daily. Speech recognition powers Virtual Assistant applications widely used now. Computer Vision scans documents and QR codes through camera apps. Standardized communication methods make many input devices interchangeable effectively.