Blindness Common Keypad with Braille When a person has become blind, in order to “see” the world, their other senses become heightened. An important sense for the blind is their sense of touch, which becomes more frequently used to help them perceive the world. People that are blind have displayed that their visual cortices become more responsive to auditory and tactile stimulation. Braille allows the blind to be able to use their sense of touch to feel the roughness, and distance of various patterns to be used as a form of language. Within the brain, the activation of the occipital cortex is functionally relevant for tactile braille reading, as well as the somatosensory cortex. These various parts of the brain function in their own way, in which they each contribute to the effectiveness of how braille is read by the blind. People that are blind also rely heavily on Tactile Gnosis, Spatial<unk> , Graphesthesia, and Two-point<unk> . Essentially, the occipital cortex allows one to effectively make judgements on the distance of braille patterns, which is related to spatial<unk> . Meanwhile, the somatosensory cortex allows one to effectively make judgements on the roughness of braille patterns, which is related to two-point<unk> . The various visual areas in the brain are very essential for a blind person to read braille, just as much as it is for a person that has sight. Essentially, whether one is blind or not, the perception of objects that involves<unk>  is not impaired if one cannot see. When comparing people that are blind to people that have sight, the amount of activity within their somatosensory and visual areas of the brain do differ. The activity in the somatosensory and visual areas are not as high in tactile gnosis for people that are not blind, and are more-so active for more visual related stimuli that does not involve touch. Nonetheless, there is a difference in these various areas within the brain when comparing the blind to the sighted, which is that shape<unk>  causes a difference in brain activity, as well as tactile gnosis. The visual cortices of blind individuals are active during various vision related tasks including<unk> , and the function of the cortices resemble the activity of adults with sight. Chronic pain Some non-neuropathic chronic pain conditions have been shown to decrease tactile acuity, the ability to precisely detect touch. There is a difference between different chronic pain conditions and how they affect tactile acuity deficits. One of the conditions with the most profound deficits in tactile acuity is arthritis. This condition affects the tactile acuity both at the site of the pain and at remote locations away from the pain. This suggests that the deficit may be a result of a cortical reorganization, or cortical remapping in the patient's brain. Other conditions, like complex regional pain syndrome and chronic lower back pain, show deficits only at the site of pain. Still other conditions like burning mouth syndrome shows no deficit in tactile acuity at all. Although there is evidence that some chronic pain conditions cause a decrease in tactile acuity there is no evidence to suggest when this deficit becomes clinically meaningful and affects the function of the patient. Robotic<unk>  Early robotic prosthetic hand, made in 1963. On open public display at the main shopping mall in Belgrade. As robots and prosthetic limbs become more complex the need for sensors capable of detecting touch with high tactile acuity becomes more and more necessary. There are many types of tactile sensors used for different tasks. There are three types of tactile sensors. The first, single point sensors, can be compared to a single cell, or whiskers, and can detect very local stimuli. The second type of sensor is a high spatial resolution sensor which can be compared to a human fingertip and is essential for the tactile acuity in robotic hands. The third and final tactile sensor type is a low spatial resolution sensor which has similar tactile acuity as the skin on one's back or arm. These sensors can be placed meaningfully throughout the surface of a prosthetic or a robot to give it the ability to sense touch in similar, if not better, ways than the human counterpart.
Tactile discrimination
Affective sensation
Color vision
Visual perception
Sensation 
Visuospatial function
Visual object recognition 
Tactile graphic