Reduced local field potential power in the medial prefrontal cortex by noxious stimuli.
Nociceptive signals produced by noxious stimuli at the periphery reach the brain through ascending pathways. These signals are processed by various brain areas and lead to activity changes in those areas. The medial prefrontal cortex (mPFC) is involved in higher cognitive functions and emotional processing. It receives projections from brain areas involved in nociception. In this study, we investigated how nociceptive input from the periphery changes the local field potential (LFP) activity in the mPFC. Three different types of noxious stimuli were applied to the hind paw contralateral to the LFP recording site. They were transcutaneous electrical stimulations, mechanical stimuli and a chemical stimulus (formalin injection). High intensity transcutaneous stimulations (10V to 50V) and noxious mechanical stimulus (pinch) significantly reduced the LFP power during the stimulating period (p<0.05), but not the low intensity subcutaneous stimulations (0.1V to 5V) and other innocuous mechanical stimuli (brush and pressure). More frequency bands were inhibited with increased intensity of transcutaneous electrical stimulation, and almost all frequency bands were inhibited by stimulations at or higher than 30v. Pinch significantly reduced the power for beta band and formalin injection significantly reduced the power of alpha and beta band. Our data demonstrated the noxious stimuli-induced reduction of LFP power in the mPFC, which indicates the active processing of nociceptive information by the mPFC.
Department of Psychology, The University of Texas at Arlington, 501 South Nedderman Drive, P. O. Box 19528, Arlington, TX 76019, USA.
Ai-Ling
AL
Li
School of Optical and Electronic Information, Huazhong University of Science and Technology, Wuhan, China.
Xiaofei
X
Yang
Department of Electrical Engineering, The University of Texas at Arlington, 501 South Nedderman Drive, P. O. Box 19528, Arlington, TX 76019, USA.
Jung-Chih
JC
Chiao
Department of Psychology, The University of Texas at Arlington, 501 South Nedderman Drive, P. O. Box 19528, Arlington, TX 76019, USA. Electronic address: ypeng@uta.edu.
Yuan Bo
YB
Peng
D000513:Alpha Rhythm / Q000502:physiology; D000818:Animals; D001611:Beta Rhythm / Q000502:physiology; D003344:Cortical Synchronization / Q000502:physiology; D005557:Formaldehyde; D006614:Hindlimb / Q000503:physiopathology; D008297:Male; D008839:Microelectrodes; D023421:Models, Animal; D059226:Nociceptive Pain / Q000503:physiopathology*; D010812:Physical Stimulation; D017397:Prefrontal Cortex / Q000503:physiopathology*; D017207:Rats, Sprague-Dawley; D059015:Wireless Technology
D005557:Formaldehyde
Local field potential; Medial prefrontal cortex; Noxious stimuli