5109-A Neurosciences Research Building
(919) 966-1291 office
(919) 966-5827 lab
bwhitsel@med.unc.edu

Biosketch

Center & Program Memberships:
- Neurobiology Curriculum
- Sensory Disorders Postdoctoral Training Program

 

Barry Whitsel , PhD
 Professor

Education:

BA, Gettysburg College 1959
MS, University of Pennsylvania 1963
PhD, Univerisity of Illinois 1969

Sensory Neurophysiology and Neuropharmacology

Our laboratory carries out in vivo and in vitro studies of the regions of mammalian cerebral cortex that process information about mechanical and thermal events on the skin.  We use neurophysiological recording methods and the method of near-infrared (IR) optical intrinsic signal imaging  to monitor the response of individual neurons and large cortical neuron populations to controlled input drive.  In addition, we carry out computer simulations of the behavior of artificial neural networks having connectional and cellular / molecular mechanisms resembling those present in somatosensory cortex.


(click for larger image)
The available evidence indicates that (i) very large numbers of somatosensory cerebral cortical neurons are activated by even a localized stimulus to the skin, (ii)  the neurons activated by such a stimulus are widely distributed and form a highly periodic spatial pattern, and (iii) the numbers of active neurons and their spatial distribution change systematically and reproducibly when the stimulus is delivered repetitively.

The main questions addressed by our ongoing studies are: (1) What aspects of a sensory stimulus are represented by such global, complex, and dynamic somatosensory cortical activity patterns?;  and  (2) What cellular / connectional  mechanisms are involved?   We also are attempting  to characterize the distorted patterns of cortical activation evoked by vibratory and thermal skin stimuli  subsequent to procedures (e.g., neurological damage or hallucinogenic drug administration)  known to produce characteristic disturbances of somatosensory perception in man.

Recent Publications:

Tommerdahl, M. and Whitsel, B. (1996). Optical imaging of intrinsic signals in somatosensory cortex. In: "Somesthesis and the Neurobiology of the Somatosensory Cortex". Franzen, O., Johansson, R., and Terenius, L. (Eds.). Birkhauser Verlag Basel, Switzerland, pp. 369-384.

Tommerdahl, M., Whitsel, B.L., Vierck, C.J., Jr., Favorov, O., Juliano, S., Cooper, B., Metz, C., and Nakhle, B. (1996). Effects of spinal dorsal column transection on the response of monkey anterior parietal cortex to repetitive skin stimulation. Cerebral Cortex. 6:131-155.

Tommerdahl, M., Delemos, K.A., Vierck Jr., C.J., Favorov, O., and Whitsel, B. (1996). Anterior parietal cortical response to tactile and skin-heating stimuli applied to the same skin site. J. Neurophysiology 75:2662-2670.

Vierck, C.J., Jr., Cannon, R.L. Fry, G., Maixner, W., and Whitsel, B. L. (1997). Characteristics of temporal summation of second pain sensations elicited by brief contact of glabrous skin by a preheated thermode. J. Neurophysiology 78:992-1002.

Kohn, A., Pinheiro, A., Tommerdahl, M.A. and Whitsel, B.L. (1997). Optical imaging in vitro provides evidence for the minicolumnar structure of the cortical response. Neuroreport 8:3513-3518.

Whitsel, B.L., Favorov, O., Delemos, K., Lee, C-J., Tommerdahl, J., Essick, G., and Nakhle, B. (1998). SI  neuron response variability is stimulus-tuned and NMDA receptor-dependent.  J. Neurophysiology 81:2988-3006.

Tommerdahl, M., Delemos, K.A., Whitsel, B.L., Favorov, O.V., and Metz, C. B. (1998). The response of anterior parietal cortex to cutaneous flutter vs. vibration.  J. Neurophysiology  82:16-33.

Tommerdahl M, Whitsel BL, Favorov OV, Metz CB, O'Quinn BL (1999). Responses of contralateral SI and SII in cat to same-site cutaneous flutter versus vibration. J Neurophysiol. 82(4):1982-92.

Whitsel, B. L., Kelly, E. F., Delemos, K. A., Xu, M., and Quibrera, P. M. (2000). Stability of rapidly adapting (RA) afferent entrainment vs. responsivity. Somatosensory & Motor Research 17(1):13-31.

Whitsel, B. L., Tommerdahl, Kohn, A., Vierck, Jr., C. J., and Favorov, O. (2000). Chapter 3, The SI Response to Noxious Skin Heating As Revealed By Optical Intrinsic Signal (OIS) Imaging,  In: “Pain Imaging”, Bushnell, M. C. and Casey, K. (eds.) IASP Press, pp. 47-93.

Kohn A, Metz C, Quibrera M, Tommerdahl MA, Whitsel BL (2000). Functional neocortical microcircuitry demonstrated with intrinsic signal optical imaging in vitro. Neuroscience 95(1):51-62.

Favorov, O., Hester, J. T., Kelly, D. G., Tommerdahl, M., and Whitsel, B.L. (2001). Lateral interactions in cortical networks. In: Somatosensory Processing: From Single Neuron to Brain Imaging, Rowe, M. J. (ed.), Harwood, pp. 187-207.

Whitsel, B. L., Kelly, E. F., Xu, M., Tommerdahl, M., and Quibrera, M. (2001). Frequency-dependent response of SI RA-class neurons to vibrotactile stimulation of the receptive field. Somatosensory & Motor Research 18: 263-285.

Kohn, A., and Whitsel, B. L. (2002). Sensory cortical dynamics. In: “Brain Mechanisms of Tactile Perception”, Franzen, O. Muhammed, A., and Terenius, L., (eds.), Special Issue of Brain and Behavioral Science, In Press.

Tommerdahl, M., Favorov, O.V., and Whitsel, B.L. (2002). Optical imaging of intrinsic signals in somatosensory cortex. In: “Brain Mechanisms of Tactile Perception”, Franzen, O. Muhammed, A., and Terenius, L., (eds.), Special Issue of Brain and Behavioral Science, In Press.

Whitsel, B. L., Kelly, E. F., Quibrera, M., Tommerdahl, M., Li, Y., Favorov, O. V., Xu, M., and Metz, C.B. (2002). Time-dependence of SI RA neuron responses to cutaneous flutter stimulation. Somatosensory & Motor Research, In Press.

Li, Y., Kelly, E.F., Tommerdahl, M., Metz, C. B. and Whitsel, B. L. (2002). Modification by noxious skin heating of SI RA neuron dynamics. Neuroscience Abstract 28.