OHSU

Lee T. Robertson

Lee T. Robertson Lee T. Robertson, Ph.D. (1973, University of Oregon Medical School)

Professor

Research Interests

Sensorimotor integration in the basal ganglia

The goal of our work is to understand how the nervous system controls complex movements, such as mastication. We are interested in how the brain organizes volitional control and external sensory input to regulate the muscles controlling the jaw and the other orofacial structures. Our approach is to study people with neurological disorders of specific brain areas that disrupt jaw movements and swallowing. Physiological recordings are made of jaw movements, muscle activity, and associated forces during volitional, rhythmic, and sensory-triggered jaw movements. Diseases affecting the basal ganglia (e.g., Parkinson’s disease) result in a slowing of the opening and closing phases of volitional jaw movements and a decrease in biting force. A recent project of our laboratory is the study of the effects a new treatment (deep brain stimulation) for Parkinson’s disease, in which different parts of basal ganglia received high frequency electrical stimulation. Our study indicates that the electrical stimulation combined with levodopa therapy results in disinhibition of the jaw opening motor neurons when the patient makes rhythmic jaw movements, such as during chewing.

Sensory responses of oral mechanoreceptors

Collaborative studies, with Dr. Jay Levy, use a psychophysical approach to understand the role of oral mechanoreceptors in the control of the mandible. Our results suggest that incisor teeth encode a wide range of vibration frequencies, which contribute to the perception of textures of a food bolus within the oral cavity.

Research Support

National Institutes of Health

Representative Publications

Robertson LT, Levy JH, Petrisor D, Lilly DJ, Dong WK. Vibration perception thresholds of human maxillary and mandibular central incisors.Arch Oral Biol. 2003 Apr;48(4):309-16.

Robertson LT. Memory and the brain.J Dent Educ. 2002 Jan;66(1):30-42. Review.

Robertson LT, Horak FB, Anderson VC, Burchiel KJ, Hammerstad JP. Assessments of axial motor control during deep brain stimulation in parkinsonian patients. Neurosurgery. 2001 Mar;48(3):544-51; discussion 551-2.

Robertson LT. A survey of neuroscience courses for predoctoral dental students. J Dent Educ. 2000 Jun;64(6):416-21.

Robertson LT. Teaching physiology to predoctoral dental students. J Dent Educ. 1997 Oct;61(10):787-94.