Sensing

Sensing is the process by which organisms or systems detect stimuli from their environment or internal state and convert them into signals that can be interpreted. Biological sensing relies on specialized receptors that transduce energy from the world into neural activity, which is then processed by the nervous system.

In biology, receptors respond to various modalities. Humans rely on vision, audition, taste, smell, and somatosensation (touch, temperature, and pain). Additional senses such as proprioception (body position) and vestibular sense (balance) provide information about movement and orientation. In other animals, the repertoire of senses includes infrared detection, echolocation, magnetoreception, and chemical sensing in the gustatory and olfactory systems. Sensing is typically paired with signaling pathways, adaptation, and, for many cues, threshold and dynamic range limits.

In technology, sensing refers to devices that detect physical quantities and convert them into electrical signals. A sensor, often with a transducer, turns a stimulus into an output that can be measured. Systems include signal conditioning, calibration, and data acquisition. Typical sensors measure temperature, pressure, humidity, position, velocity, acceleration, light, sound, chemical concentrations, and biological markers. Sensors can be passive (responding to ambient energy) or active (requiring energy input).

Key considerations include accuracy, sensitivity, dynamic range, response time, durability, and resistance to noise and drift. Sensing is foundational to measurement, control systems, and perception, linking raw stimuli to actionable information.

Applications span medicine, environmental monitoring, industrial automation, robotics, and consumer electronics, where sensors enable diagnostics, safety, efficiency, and automation.