I direct student-based research that examines the anatomy of vertebrates focusing on the functional anatomy of vision. Students in my laboratory investigate the functional anatomical mapping of the turtle retina to address how the vertebrate retina processes color and motion. In addition to the functional morphology of the turtle retina, other brain areas are examined to investigate reflexive eye movements: the pupillary response to light and the response to rapidly approaching targets. Student projects also examine the control of eye movements for tracking targets moving in depth. My biological research interests intersect with the field of neuroscience.
1. Functional anatomical mapping of the turtle retina. The turtle possesses one of the most complex retinas found among vertebrates. Using this neural network, my research investigates the anatomical substrates underlying sensory processes which lead to visual functions. My laboratory uses electrophysiological, pharmacological, and molecular methods to examine the anatomy and function of the retina. One of our recent studies identified melanopsin in the retina the turtle.
Marcincin, C.L. (’06) & Dearworth, J.R., Jr. (2006). Computer image analysis of retinal oil droplets in different vertebrate species. Journal of the Pennsylvania Academy of Science 79: 116 (abstract).
2. Sensory processing done by the retina evokes reflexive motor behaviors which help protect the eye and aid in image formation. These include the pupillary light response and eye blinks. Light responses evoking pupil closure can even be initiated by photoreception occurring within iris cells themselves.
Dearworth, J.R., Sipe, G.O. (’10), Cooper, L.J. (’07), Brune, E.E. (’05), Boyd, A.L. (’06), & Riegel, R.A.L. (’07) (2010). Consensual pupillary light response in the red-eared slider turtle (Trachemys scripta elegans). Vision Research 50 , 598-605. PMID: 20079368
3. Sensory processes in the retina also initiate more complicated behaviors. In humans and other frontal eyed animals, these include vergence eye movements, the eye movements used for tracking targets moving in depth. Eyes converge to track targets moving inward and diverge to track targets moving away.
4. I design my courses so that students are given a practical hands-on approach. These include performing laboratory exercises, critiquing primary literature sources, and designing research projects.