Afferent Pain Pathways: a Neuroanatomical Review
Brain Research 1000 (2004) 40–56 www.elsevier.com/locate/brainres Review Afferent pain pathways: a neuroanatomical review Tatiana F. Almeida*, Suely Roizenblatt, Sergio Tufik Department of Psychobiology, Universidade Federal de Sa˜o Paulo, Rua Napolea˜o de Barros, 925. Vila Clementino, 04024-002, Sa˜o Paulo, SP, Brazil Accepted 23 October 2003 Abstract Painful experience is a complex entity made up of sensory, affective, motivational and cognitive dimensions. The neural mechanisms involved in pain perception acts in a serial and a parallel way, discriminating and locating the original stimulus and also integrating the affective feeling, involved in a special situation, with previous memories. This review examines the concepts of nociception, acute and chronic pain, and also describes the afferent pathways involved in reception, segmental processing and encephalic projection of pain stimulus. The interaction model of the cerebral cortex areas and their functional characteristics are also discussed. D 2004 Elsevier B.V. All rights reserved. Theme: Sensory systems Topic: Pain pathways Keywords: Nociception; Afferent pain pathway; Tract; Supraspinal projection; Cortical structure 1. Introduction characterized as nociceptive pain. However, it is known that the painful phenomenon can occur spontaneously, as is the In 1986, the International Association for the Study of case for nonnociceptive pain represented by the reduction of Pain (IASP) defined pain as a sensory and emotional expe- the receptor thresholds due to alterations of the central rience associated with real or potential injuries, or described nervous system (CNS) [22]. There is a difference between in terms of such injuries. Pain has an individual connotation the terms nociception and pain; the first refers to the neuro- and suffers the influence of previous experiences [75].
[Show full text]