Anterior Cingulate Cortical Neuronal Activity During Perception of Noxious Thermal Stimuli in Monkeys

• Published in: Journal of neurophysiology 2005-09, Vol.94 (3), p.1980-1991
• Main Authors: Iwata, Koichi, Kamo, Hiroshi, Ogawa, Akiko, Tsuboi, Yoshiyuki, Noma, Noboru, Mitsuhashi, Yutaka, Taira, Masato, Koshikawa, Noriaki, Kitagawa, Junichi
• Format: Article
• Language: English
• Subjects: Action Potentials - physiology; Action Potentials - radiation effects; Animals; Brain Mapping; Dose-Response Relationship, Radiation; Escape Reaction - physiology; Escape Reaction - radiation effects; Gyrus Cinguli - cytology; Hot Temperature; Macaca fascicularis; Neurons - physiology; Nociceptors - physiology; Physical Stimulation - methods; Psychomotor Performance - physiology; Reaction Time - physiology; Reaction Time - radiation effects; Thermosensing - physiology; Time Factors
• ISSN: 0022-3077; 1522-1598
• DOI: 10.1152/jn.00190.2005

1 Department of Physiology, Nihon University, School of Dentistry, Tokyo; 2 Division of Functional Morphology, Dental Research Center, 6 Department of Pharmacology, and 7 Department of Prosthodontics, Nihon University School of Dentistry, Tokyo; 3 Division of Applied System Neuroscience Advanced Medical Research Center, Nihon University Graduate School of Medical Science, Tokyo; 4 Department of Oral and Maxillofacial Surgery, Nihon University, School of Dentistry, Tokyo, Japan; and 5 Department of Physiology, College of Osteopathic Medicine, University of New England, Biddeford, Maine Submitted 23 February 2005; accepted in final form 28 May 2005 It has been reported that the anterior cingulate cortex (ACC) has a variety of functions relating to pain as well as pain perception. However, the underlying mechanisms for those functions remain unclear. To elucidate the functional role of the ACC in pain perception and pain-related functions such as attention to pain and escape from pain, single neuronal activity was recorded from the ACC, and the behavioral correlates of this neuronal activity was studied. A total of 667 neurons were recorded from the ACC in awake behaving monkeys. Twenty-one had modulated activity during a heat-detection task. Eighteen of these increased their firing frequency following an increase in stimulus temperature, whereas three of them had decreased firing during heating of the face. Seventy-five percent of heat-evoked responses of heat-responsive ACC neurons were significantly depressed when monkeys detected the change in magnitude of illumination of a light presented on the front panel. The neuronal activity was significantly higher when monkeys escaped from a noxious heat stimulus than when the monkeys detected a small change in temperature (T2) above a larger initial shift (T1). No relationship between firing frequency and detection latency of the T2 stimulation was observed. These findings suggest that ACC nociceptive neurons are involved in attention to pain and escape from pain but not in the sensory discriminative aspect of pain. Address for reprint requests and other correspondence: K. Iwata, Dept. of Physiology, School of Dentistry, Nihon University, 1-8-13 Kandasurugadai, Chiyoda-ku Tokyo, 101-8310 (E-mail: iwata-k{at}dent.nihon-u.ac.jp )