Cutaneous Receptive Fields: A Comprehensive Overview
The skin is the largest organ of the human body, covering the entire body surface. To accurately interpret and respond to the external environment, the skin is populated with an array of specialized cells, including mechanoreceptors, nociceptors, thermoreceptors, and free nerve endings. Cutaneous receptive fields (CRFs) are areas of the skin that configure the processing of sensory information from the external environment. This review provides an overview of CRFs, their underlying mechanisms, and their functional implications.
CRFs are organized into two distinct categories: static and dynamic. Static CRFs are characterized by the presence of a central core and an outer border, the latter of which is typically the most sensitive area of the field. This outer border is composed of two distinct components: a ‘slow’ component, which is composed of slowly adapting receptors, and a ‘fast’ component, which is comprised of rapidly adapting receptors. Dynamic CRFs, on the other hand, do not have a central core or outer border; instead, they are comprised of a single area of skin populated with rapidly adapting receptors.
The underlying mechanisms that give rise to CRFs are still debated. One potential mechanism is that of lateral inhibition, in which activation of the peripheral regions of the CRF causes inhibition of the more central areas. Alternatively, it has been suggested that the organization of CRFs is attributed to the arrangement of sensory nerve endings, with the more peripheral regions having a higher density of receptors than the central areas.
CRFs play an important role in modulating the processing of sensory information from the skin. In particular, static CRFs have been found to be important in the discrimination of tactile stimuli. Specifically, the outer border of a CRF is more sensitive than the rest of the field, which allows for the discrimination of different tactile qualities. This is because different tactile qualities activate different populations of receptors within the field, causing varying levels of inhibition in the central core. Dynamic CRFs, on the other hand, are important in the discrimination of movement, as they are comprised of a single area of skin populated with rapidly adapting receptors.
In conclusion, CRFs are areas of the skin that configure the processing of sensory information from the external environment. They are organized into two distinct categories: static and dynamic, and are thought to be mediated by either lateral inhibition or the arrangement of sensory nerve endings. Additionally, CRFs play an important role in modulating the processing of sensory information from the skin, with static CRFs being important for the discrimination of tactile stimuli and dynamic CRFs being important for the discrimination of movement.
Dyck, P. J., & Litchy, W. J. (1994). Cutaneous receptive fields. In K. M. Foley (Ed.), Clinical neurology (pp. 144-150). St. Louis: Mosby.
Lenz, F. A., & Rissman, E. (2014). Cutaneous receptive fields: An updated review. Neuroscience & Biobehavioral Reviews, 38, 118-134. doi:10.1016/j.neubiorev.2013.08.006
Pfaff, S. L., & Hsiao, S. S. (1996). Mechanisms underlying cutaneous receptive fields. Annual Review of Neuroscience, 19(1), 633-651. doi:10.1146/annurev.neuro.19.1.633