We currently have multiple openings for Postdocs and/or engineers for two newly funded studies. Detailed descriptions of each study are listed below. If interested, please send a CV to Dr. Dawn Taylor at
dxt42@case.edu.
1)
The goal of the
Parkinson's project is to understand how Parkinson's
disease alters cortical network processing and how
Deep Brain Stimulation (DBS)
can be improved to better re-normalize motor processing. Cortical
network activity will be recorded in monkeys via intracortical electrode
arrays before and after making
the animals hemi-Parkinsonian via injections of the selective neurotoxin
MPTP (note this toxin is initially applied in such a way that the animal only
develops parkinsonian symptoms on one half of its body so the animal can
still groom, ambulate, and take care of itself). DBS will then be
applied
to two subcortical regions (subthalamic nucleus and globus pallidus) to
alleviate Parkinsonian symptoms. Computational models of
the cortical microcircuit will be developed that accurately reflect the
recorded cortical activity in the normal and Parkinsonian states as well
as under the influence of different DBS patterns. The model parameters
that need to be changed to make the network computational model behave
like the recorded experimental data under the different conditions will
be informative regarding the underlying mechanisms of DBS. The refined
computational
model will also be used to rapidly screen for new DBS
patterns that are more effective at restoring normal cortical network
processing. The improved DBS patterns suggested by the computational
model will then be validated by testing those novel patterns in the
monkeys. This
project is being done in conjunction with Dr. Cameron McIntyre who will
oversee the computational modelling part of the study. We are looking
for multiple post docs that can focus on either the animal
work, the
computational modeling, or both depending on their skills and interests.
2)
The long-term goal of the
Neuroprosthetics project is to
enable paralyzed
individuals to use their brain signals to control their upper limb via
implanted muscle stimulators. Most labs working on brain-controlled
neuroprosthetics decode
intended limb kinematics (e.g. velocity, joint angles, etc.) from the
recorded brain signals. However, that approach still requires converting
those
kinematic commands into the appropriate stimulation patterns required to
generate the desired limb motion. That conversion process has not been
resolved for the upper limb due to the limb's complex dynamical nature
and the
fact that the limb is subject to unknown external forces during use. We
bypass this obstacle by retraining the brain to control muscle
stimulators directly. We have come up with some novel, but clinically
feasible ways of mapping neural signals directly to muscle stimulators.
Our methods can enable the user to have good control over both limb
motion and stiffness.
To demonstrate and refine our methods, we are training monkeys to
control
the movements of a realistic musculoskeletal model of a paralyzed limb activated
via
implanted muscle stimulators. The paralyzed limb simulator (developed by
the lab of Robert Krisch) provides real-time visual feedback to the
animal of the limb motion that would result from stimulating the
paralyzed muscles based on the animal's neural signals decoded in real time. The
use of this real-time paralyzed arm simulator allows
us to test and refine our process of brain-controlled muscle stimulation
in monkeys
without actually having to paralyze
any animals.