Just to review this is part
of the degree process to

your master science rustics this
initially the cast of research project.

It's a program requirement.

It's a component of the research seminar
series which consists of three semesters

of easy applied research seminar
the research is mentored

but it is independent research by
the students part of the then I'll

get patient is an oral presentation
which is what we're doing today.

And there's also a written
report in the form of

a man your script of
the scientific journal.

So our speakers today we're
going to change this order but

our speakers today will be the owner
Brown Ruth and Meghan Krauss

and I should also like to mention that
next week is our third lecture series and

that is a different location
that will be at the C.R.B.

lecture venue and there will be
four students presenting And so

we're going to go an extra twenty minutes
on that gay so if you can set another

twenty minutes extra set aside to
get off for those presentations and

so with that I would like to
introduce them to the list.

So I gave them my name is Victor prison
I'll be presenting on cortical activation

during two a pantomime with upper
extremity prostheses I worked with

Dr Chris and I though Rob his American
doctor Louis Wheaton on this project.

So we were interested in upper
extremity N.P.C. is in how they control

movement cortically And so we are looking
specifically at practice which is the.

Action initiation organization and
performance and so even more specifically

we wanted to look at tool used because
this is an area of motor control

that is very well understood and
there's a lot of literature about this.

So we wanted to ultimately compare brain
activation of this downside versus

the effect of side of the SHE'S while
they perform simple movements and

tool can some I'm just so
why would you expect to see differences

in the brain activity of me in
P.C.'s One reason is physiological So

when you lose any part of your anatomy
the pathway between the brain and

that anatomy is disrupted and this leads
to sensory and motor input effects and

so this peripheral loss can actually
lead to cortical reorganization and

this is also been well documented
in many N.P.C. population.

Another reason that you might expect
to see differences in this population

is due to the mechanism of action
of the devices that they use.

So obviously a prosthetic arm is very
different from an answer from an arm in

one of those ways it's
different is how it moves and

how you control all the components and

even within different prostheses designs
there are different mechanisms of action.

So.

Here at the bottom is an example of a body
powered device which is cable operated and

I realized I'm grossed movements of
the shoulder girdle it's the power of

the components and then here is
an example of a mile a lecture device and

that requires very isolated muscle
movements to power the components.

So because of these different
mechanisms of action.

You might expect that the brain
would have to process moving

these devices differently than
the an atomic or sound arm.

Another important difference between
prostheses in the anatomic arm is

feedback so

of course you're not receiving any sensory
input from the device to the brain.

So you have no idea where the arm is and

Feaster touch pain perception and
things like that are all lost.

So because to use has been so
well documented.

We've been pointed.

In the brain where these process
these are represented so

the left temporal area is shown here
in green process tool familiarity

the left frontal area is shown here in
red process how you grasp objects and

how you orient them to use them
functionally and the left cortex here and

yellow sort actually stores
representations of tool characteristics

and together these left brain areas make
up what we call the neural tool network.

So one thing that was really driving
our study was to improve prosthetic

outcomes for a brick chimney in Q.C.'s
this is a really small population for

example in two thousand and
seven there are only five hundred

eighty eight new opportunities in the
United States and only about fifty percent

of these users have been documented
to actually use prostheses daily.

And this lack of press this use has been
attributed to a lack of education about

their prosthetic options in prosthetic
care a lack of training with their devices

discomfort in the socket poor
cousin uses a high cost and

the fact that people can adapt
to one handed life very quickly.

So the intervention has to occur
before the adaptation occurs.

The aim of the study was simply to
determine if there are differences in

brain activity during prosthetic and
downside use an aborigine in P.C.'s and

we wanted to understand this that we can
understand how prostheses are processed by

the brain and ultimately we'd like to
use this information to guide prosthetic

device design and training paradigms to
maximize the function of these devices.

We had to have this these first we have
prophesies that during simple movements in

space with the process these
says that amputees would exhibit

higher activity in the neural tool
networks relative to their sound side so

basically we're hypothesizing that their
prostheses are used as external tools.

Instead of extensions of their anatomy.

And we have publicized this because
there is probably a dissociation between

the process these this and
the anatomy of the patient.

We also have hospice eyes
that during tool used to.

And so my what the prostheses is there
would be an additive effect of the neural

network activation again
relative to their sound side.

So we use a lecture and so far afield to
measure cortical activation We also use

electro my auger we see an objective
record of when movements occurred and

we use the deltoid muscles to do this.

So each participant performed two tasks.

And all the tasks were performed with the
affected side as well as the down side.

So the first test was simply to reach
out and rotate their forearm and

then everybody watched a video
of someone using a screwdriver.

And then they were asked to
pantomime using a screwdriver so

we just instructed them to show us
how you would use a screwdriver and

again this is what their prosthesis and
there's downside.

They were instructed to perform each
movement for about every ten seconds and

each child lasted for
about twelve minutes.

So this is just a picture of
what our set up looked like

here you can see the white wires or the
electrodes going to the deltoid again so

we could measure movement on that.

And he is wearing a cap you can
see a little bit of it there.

He's just sit comfortably in a chair and
all of the.

All the tasks were performed in the seated
position and just to go over our protocol

so it's clear each subject perform the
simple rotation and these with their sound

and prosthetic side but not necessarily
in that order then they watched a video

of an able bodied person using
a screwdriver and then they were asked to

perform the tool pantomime again with
their sound and their prosthetic side.

And here's just a little information
about our participants and

we analyzed the data from seven
individuals we had six meals and one

female the age range from twenty four to
sixty years with a mean of forty one point

seven years there were three different
levels of amputation involved in our study

five individuals had a trans radial or
forearm imputation one individual had

a trans humoral or upper arm amputation
and one had a partial hand amputation.

We had a pretty even split
between the affected side so

three individuals had a left amputation
and four individuals how to write.

Imputation the time since the invitation
varied pretty widely we had anywhere from

two to thirty eight years the time until
the time from their invitation until

their first prosthetic fitting range
from zero to twenty four months and

there are also two different types of
prostheses represented so for individuals

completed the tasks with a body powered or
cable operated prosthesis while three

perform the tasks with the myoelectric
are extremely powered prosthesis and

all of our subjects involved in
the analysis were right hand dominant.

So we use movement onset to sort of anger
our trials and we just cut them up so

that they started forty five hundred
milliseconds before movement on that and

did fifteen hundred milliseconds
after movement onset.

And we did this because we were really
interested in the moving movement planning

phase of the task as well as execution.

And so the way that we actually
measured cortical brain activity was to

use a metric called event
related to synchronize ation and

this is something that's commonly used
to measure brain activity and it just

involves measuring the oscillations of
different neurons of groups of neurons in

different parts of the brain at
different frequencies no big deal.

So increase.

Basically all you need to know to
understand my data is that increase

is related to increased cortical activity
in the region that the increase was shown.

And so just to kind of give you an idea of
you know how we actually analyze the data.

This represents just raw E.G.

signals which is what I showed
you a couple slides ago.

And here's where you bandpass filter
to get to the actual data the actual

frequency that you're interested in our
case we looked at Beta frequency because

that is associated with motor activity you
then just square the data see if you can

look at the power of the signal and then
you average it over all your tries child

and this is what I really want you to pay
attention to is just a representative

example of E.R.D. so you can see
the baseline here and then the relative

decrease in powers that this is what we're
referring to when we actually talk about.

And here is our actual data so.

What you're looking at here aerial views
of the brain activity this is the nose or

the interior part of the head and these
are the ears of the lateral sides and

I just broke this up
into each condition and

within each condition the head plots
are broken up and so for a time bands.

So these top head plots are just
represent motor planning or

any observation before movement onset.

And these have parts just represent motor
execution or any activity after movement

onset on the left column is where I
show all the downside oxidation and

on the right column is where I show
the prosthetic side of activation and

then on the top row is during
this simple four arm rotation and

the bottom row shows
the screwdriver pantomime.

And on the color scale here.

The darker the blue indicates higher or
higher brain activity.

So you can see here when the individuals
were performing this simple routine and

with their sound side.

You just see a very typical activation
over the motor cortex which

comes out during cleaning and goes through
to execution and this is what you would

expect to see in any population and
here when they perform the tool can some

I'm with their sound side you get
see something that we expect you see

this neural network left lateralized
activation that I spoke about earlier.

And this is highly indicative
of a tool related task and

again this makes sense because they
were performing at all related tasks.

However when we look at the prosthetic
side we see very different

patterns of activation
during the same movements.

So here during the prosthetics.

Simple rotation in space
you see this very focal

post serial prattle activation that again
is indicative of tool use so this is

supporting our hypothesis that the process
these this is actually used as a tool.

However when you look at their
activation during the tool

can sometimes task with their prosthesis
you see something totally different.

You see this right lateralized
activation which we did I

hypothesize that we would see in our
talk more about why we saw that leader.

So something we were curious about
was to see if there was an effect of

dominance on our data.

So what I did here is I just pulled
everyone's right arm data and

because everyone was right.

Dominant we're looking at everyone's
dominant side now certain individuals had

an intact right arm and those are shown on
the left side and other individuals had

an amputated or prosthetic right arm
which they show on the right side here.

And so everything else is
the same about these plots and so

just what I want to point out is that
we're seeing the same patterns of

activation in each of
the conditions here so

you see the focal length post your private
activation during a simple movement with

the prosthesis which again is indicative
of tool use and then you see this right.

Lateralized activation during toolkits
mind with the press thesis which

again I'll explain a little bit more of
that leader and I also just want to point

out that here when we're we're just
looking at right arm movements we do see

a left motor cortex activation which
sort of validates our measures and so

we know that the contra Lotter old brain
hemisphere controls the right arm.

And now here I just looked at all
of the left or non-dominant sides.

So again people with an intact left
arm are shown on the left side and

people with intact left arms are amputated
left arm are shown on the right side and

again that pattern for the amputated
side holds true so you see this

very focal activation in the Post your
pride all and then you see a more right.

Lateralized activation.

During tool pantomime.

And then again you see during movements of
the intact arm just the simple movement

you see the contra lateral
motor cortex is activated.

So just to recap to make sure
everyone's on the same page.

During sound side rotation contra motor
cortex activation which is what we would

expect to see in any population and this
is consistent with performing any motion

during this downside to pantomime
we saw a less lateralized

pride of frontal activity and
again this is indicative of tool use.

And then on the prosthetic side
we saw the post Siri or pride or.

Neural tool network activated during just
the simple movement with the prosthesis

which is indicative of tool use and
it's interesting that this pattern was

displayed regardless of
the dominance of the prosthetic arm.

And during prosthetic side tool can
sometime we saw a right lateralized

activation.

And again this was displayed Regardless
dominance of that prosthetic side and

it's indicative of visual spatial
processing so explain that a little more

there have been several studies that have
shown that the right is active during

visual spatial it's how such as fine
finger movements and gesture imitation.

And so we're postulating that
because the prosthetic arm

offers no feedback to the wear
that they're forced to visually

monitor their prosthesis
while they're using it and

this is why the pantomime task sort of
turned more into a visual spatial task.

So our first hypothesis was supported
the amputated side of all the individuals

showed more opposed to your product cortex
during simple movement than their sound

side and this is indicating that
there prosthesis is used as a tool.

However our second
hypothesis was refuted so

instead of seeing even more activation
in the neural network when they're using

their prosthetic tool to
pantomime of another tool.

We saw this whole other right lateralized
activation because of the visual spatial

component to that task and I think
this raises an important question of

you know how should these
prosthesis be used.

What kind of neural activity.

Do we want to see or do we expect to see
in these patients are we going to hold

them to the standard of an able bodied or
normal person or are we going to have

another standard for these devices in
these patients and this is very similar to

a problem that we're dealing with in lower
limb prosthetics about eight parameters

and you know what kind of gate grammars
we're going to hold these patients to and

especially with all the new technology
that's coming out right now with really

impressed these I think it's a good
idea to sort of ponder this point.

So one of the main limitations of this.

But he was the variability of the patients
and because of this we weren't able to

sort of look at any more fine
differences between the patients so

future studies could look at the limits
of this visual spatial effects to do all

tasks that involve tools sort of show
this effect in prosthetic wears or

there's sort of different categories
of tasks that you could bring out.

Also be very interesting to look at
effects of device types of the body

powered versus the myoelectric controlled
or externally powered which have such

different actions of mechanism training
duration and type imputation level and

causing appreciation can also be explored
and we're hoping to look at the effects of

hand transportation on motor control
sort of looking before the procedure and

after to see what kind of
cortical changes occur.

Whoops.

I'd like to thank Dr Chris myself for
all of his help and guidance through

Matlab Dr Luke I mean of course for
all of his mentorship and guidance Rob has

emerged for his invaluable help with the
subject recruitment all my classmates for

their support and all of the participants
and all of the B. bunnies in the world.

These are my references.

So really questions for you very much.

We didn't.

So we did like a full analysis on all of
the different variables that are subject

but we weren't able to pull out any
significant differences between

any of the different variables but
of course we had a smaller sample size and

the large variability so
the same story there.

Unfortunately we did.

Yes it should be.

Honest looking at all of the different
conditions it was really hard to

pull out generalizations when you looked
at the data that way subject by subject.

He did have some differences but
it was nothing that would

be maybe explained by the different
concepts that I explained

our audience.

But no you don't so

dominance is a big effect which is
why we just want to look at right.

Dominant people but

then that's why we looked at the effect
of dominance with the effect of science.

So yeah so because there are such
lateralized networks that's why you see

the differences between
dominant dominant side of

the brain and

that's really something that we love to
look at especially looking at congenital

amputees as well and seeing you know
what kind of differences they show

compared to people who are traumatic or
later in life but

yeah it would be very interesting to look
at someone first getting the device and

that would sort of play more into training
in the type of device given to them.

Yes you

really are already read

reviews and that was something
that we delayed tried to explore

one very simple metric of that is just how
long they've been using the prostheses But

of course that doesn't get to all
the nuances of how they use it.

We also used just a survey outcome
measure but that didn't really.

A lot of the outcome of years and
prosthetics are powerful enough again

to pull out the differences so I wasn't
able to kind of see what effect that had.

Yes.

Well I think the idea here is that maybe
the device is more or less integrated

into their anatomy or into the you know
how they're using it and so if someone's

a more active wear or more functional
wear than maybe it's more integrated so

you would see less of this visual
spatial and more of just a tool network.

Yeah I think one of the biggest things
about upper extremity how it's different

is that you're looking at
really fine motor skills and

that's what these devices really lack.

And of course the feedback so
I think maybe the feedback issue would be

similar but you maybe use that feedback
really differently when you're walking and

when you're using an arm so

I think weight bearing has a lot to
do with that difference in feedback.

Cheryl.

Yeah that's a really good point which is
what most in P.C.'s and of doing anyway.

And so I can't really say
maybe what I would expect but

I definitely think that that would you
know answers and important questions about

looking at them using the processes and
looking at them to seizing their anatomy

because of course they are using
compensatory measures they're using

different muscles and so the mechanism of
action question is sort of still there.

If you think one way and one.

Sure.

So you still have that issue of feedback.

OK the cortical

Right exactly.

No it's a very good point.

OK Thank you.