Research Assistant Professor of Psychology
Iwona Stepniewska studies anatomical and functional organization of motor and sensory systems in primates.
- Posterior parietal cortex and complex motor behavior. The goal of this project is to better understand involvement of posterior parietal cortex in motor behavior. The dominant view of function is that posterior parietal cortex uses visual, somatosensory, and auditory inputs to guide eye and limb movements in space. However, few subdivisions are well defined, and connection patterns are only broadly understood. We use intracortical microstimulation technique (motor mapping) to delivered trains of electrical pulses via microelectrodes to define and describe the major movement zones in posterior parietal cortex of anesthetized monkeys and galagos and study connections of these zones with other areas and subcortical nuclei, especially with premotor cortex. The results will provide new insights into the functional organization of posterior parietal cortex, and how functions are mediated via differing connection patterns, epecially with motor fields.
- Distribution of sascending somatosensory pathways . The organization and connection patterns of two main ascending somatosensory pathways (dorsal column-medial lemniscus and spinothalamic tracts) that convey information from the skin, joints or muscles receptors to higher brain centers have not been fully understood. By injecting dorsal column nuclei and spinal cord with different tracers we study their projections to sensorimotor thalamus. Results will improve our understanding of the processing of somatosensory information, and the ways in which each of these main subcortical somatosensory structures interact with other somatosensory processing stations.
- Anatomical substrates for movement controlThe major goal of the project is to understand the interface between the basal ganglia output nuclei and the cerebellum in the production of coordinated goal directed movements. The focus is on the sources of input to the different areas in the motor cortical region in primates using anatomical tract tracing methods.