Abnormal Sensation from Numbness

SOURCE: www.RightHealth.com

Numbness and tingling are abnormal sensations that can occur anywhere in your body, but are often felt in your hands, feet, arms, or legs.

In psychology, sensation is the first stage in the biochemical and neurologic events that begins with the impinging of a stimulus upon the receptor cells of a sensory organ, which then leads to perception, the mental state that is reflected in statements like "I see a uniformly blue wall."

A sensation that might lead to that statement could include the excitation of cone cells in the retina, spatially varying in the proportion of "blue" and "green" cone excitation due to portions of the wall receiving different proportions of yellowish artificial and bluish sky-light; it is common for these variations to be compensated for, within the brain, so that the non-uniform sensation yields a perception of uniform color.

In the West, the human body's senses are divided into eight: visual, auditory, gustatory, olfactory, cutaneous, kinesthetic, vestibular, organic. The ways in which these senses are divided from one another in concept, and combined in varying ratios in perceiving the world, differs based on individual physiology, social and cultural context, and physical surroundings. The whole sensory system, including both physical sensation and interpretation (or cognition) of information from the senses, is referred to as a sensorium.