tuntuminen

Tuntuminen is a Finnish term referring to the sense of touch or tactile perception. It encompasses the ability to detect and interpret mechanical stimuli such as pressure, texture, and vibration, as well as thermal and nociceptive sensations that accompany skin contact. In everyday use, tuntuminen covers both the discrimination of surface properties and the perception of bodily contact with objects or people.

Physiology: The sense of touch relies on specialized receptors in the skin and, in some cases, deeper tissues. Mechanoreceptors include Merkel cell–neuron complexes for steady pressure and texture, Meissner's corpuscles for light touch, Ruffini endings for skin stretch, and Pacinian corpuscles for vibration. Free nerve endings detect temperature and pain. These receptors transduce mechanical or thermal energy into electrical signals carried by A-beta, A-delta, and C fibers toward the spinal cord.

Processing: Signals ascend through the dorsal columns (fine touch, vibration, proprioception) or the spinothalamic tract (pain and temperature) and reach the thalamus before projecting to the primary somatosensory cortex. The brain integrates touch with proprioception, attention, and contextual information, enabling tasks such as texture recognition, shape discrimination, and spatial localization.

Development and testing: The sense of touch develops in infancy and can decline with aging or be altered in conditions such as diabetes or nerve injuries. Clinically, touch sensitivity is assessed with tools like monofilament tests, two-point discrimination, vibration tests, and more comprehensive quantitative sensory testing.

Clinical relevance: Tuntuminen is essential for everyday interaction, dexterity, and safety. Disturbances can reflect peripheral neuropathy, central nervous system injury, or sensory processing disorders, guiding diagnosis and rehabilitation.