Robert Caudle, Ph.D. • Professor of Oral and Maxillofacial Surgery
College of Dentistry

Robert Caudle’s research focuses on the molecular and physiological processes that initiate and maintain chronic pain, with a goal of developing novel strategies to avoid the induction of chronic pain and new therapies to treat chronic pain once it is established.

Caudle is a recognized leader in the field of molecular and preclinical pain research. His research focuses on the role of N-methyl-D-aspartate (NMDA) receptors in neuronal plasticity during and following injury. His seminal work has demonstrated that the splicing of the NR1 subunit of the NMDA receptor in the spinal cord is altered following an injury. This altered splicing is a common thread between injuries to the limbs, viscera, or central nervous system.

Caudle’s group has found that, in subjects where an injury has fully healed, if the altered NMDA receptors remain, the subjects are hypersensitive to peripheral stimuli. If the receptors have reverted back to their original splicing, there is no detectable difference in behavior between the injured subjects and subjects that have never been injured. Thus these novel NMDA receptors represent the “disease state” of chronic pain. The National Institute of Neurological Diseases and Stroke awarded Caudle a grant to pursue this line of research.

One of the major concerns in pain research over the past decade has been the divergence of data collected in preclinical studies from the data collected in the clinic. Caudle designed a data collection system that more closely matches human reports of pain since it requires more complete central nervous system processing of the pain stimulus. Thus, in an effort to improve the quality of the data collected in pain studies, Caudle and colleagues developed the first high throughput behavioral assessment of pain. This device impressed Stoelting Inc. and they collaborated with Caudle and his colleagues on a small business grant from the National Institutes of Health to develop the device as a commercial product. Stoelting Inc. has named the device the Operant Pain Assessment Device (OPAD) and is currently taking orders from investigators around the world for the OPAD.