I am a Physical Therapist now reincarnated as a Neuroscientist. My PhD thesis entailed the study of adaptive arm-trunk coordination in patients with Parkinson’s disease and in proprioceptively deafferented individuals. I defended this work in 2004 under the advisorship of Dr. Howard Poizner (
My postdoctoral work, under the mentorship of Dr. Scott Grafton, builds on these issues by incorporating more advanced technology (fMRI and TMS) to directly investigate the neural substrates subserving flexible and adaptive neuromotor control. We developed a torque motor system that can be used to produce various perturbations while a person performs a reach-to-grasp or an arm rotation movement.
In one series of experiments, the motor is used to induce a visual perturbation by rapidly rotating an object (changing its shape or orientation within 50 ms) while the subject reaches to grasp it. By applying a TMS pulse to a cortical site of interest, we attempt to disrupt online adaptive response that would normally be present - providing for us not only the spatial location of the locus, but also an approximate temporal window for its participation. In another series of experiments, the torque motor system is used to apply assistive or resistive forces (either viscous or pulsatile) to the subject’s arm as (s)he rotates a handle connected to the motor shaft (motor perturbations). The torque motor system is shielded inside an inhouse-built cage making it MR compatible.
eugene.tunik -at- dartmouth.edu
Tunik E, Adamovich SV, Poizner H, Feldman AG. (2004) Deficits in rapid adjustments of movements according to task constraints in Parkinson's disease. Mov Disord. 19(8), 897-906.
Tunik E, Poizner H, Adamovich SV, Levin MF, Feldman AG. (2004) Deficits in adaptive upper limb control in response to trunk perturbations in Parkinson's disease. Exp Brain Res. PMID: 15289976
Tunik E, Poizner H, Levin MF, Adamovich SV, Messier J, Lamarre Y, Feldman AG. (2003) Arm-trunk coordination in the absence of proprioception. Exp Brain Res. 153(3), 343-355.
Messier J, Adamovich S, Berkinblit M, Tunik E, Poizner H. (2003) Influence of movement speed on accuracy and coordination of reaching movements to memorized targets in three-dimensional space in a deafferented subject. Exp Brain Res. 150(4), 399-416.
Website created by Antonia Hamilton. Last updated 12 November 2005.