<P> The mapping of the body surfaces in the brain is called somatotopy . In the cortex, it is also referred to as the cortical homunculus . This brain - surface ("cortical") map is not immutable, however . Dramatic shifts can occur in response to stroke or injury . </P> <P> The four mechanoreceptors in the skin each respond to different stimuli for short or long periods . </P> <P> Merkel cell nerve endings are found in the basal epidermis and hair follicles; they react to low vibrations (5--15 Hz) and deep static touch such as shapes and edges . Due to a small receptive field (extremely detailed info) they are used in areas like fingertips the most; they are not covered (shelled) and thus respond to pressures over long periods . </P> <P> Tactile corpuscles react to moderate vibration (10--50 Hz) and light touch . They are located in the dermal papillae; due to their reactivity they are primarily located in fingertips and lips . They respond in quick action potentials, unlike Merkel . They are responsible for the ability to read Braille and feel gentle stimuli . </P>

Carries information from fine touch and pressure receptors