Group Members Portland State University Advisor

Fahad Aldakheel Dr. Dave Turcic

Chad Knutsen Portland State University Instructor

Melanie Ferguson Dr. Sung Yi

Hamid Tavazoie Industry Advisors

Evan Topinka Gregg Meyer, MME

Dieterich Steinmetz, M.D.

Amy Walker, MPT

Winter2014

PORTLAND STATE UNIVERSITY | Mechanical Engineering Dept.

Assistive

Exercise

Machine for

Post Stroke

Rehabilitation

EXECUTIVE SUMMARY

Myoelectric Robotic Orthosis is a device created for Stroke Survivors. It senses the brain

signal to a muscle group to power a pulley system connected to the person to assist in therapeutic

activities. Our team designated a list of constraints to follow when creating the device, and have

since made modifications to that list. From research, interviews, and testing, we have made

changes to what our top priorities are.

This progress report discusses what our new priorities are, as well as comparing our

original goals with our new ones. We will evaluate our progress and delve deeper into our

internal and external research. Without a company to fund us or look up to for answers and

evaluation, we rely on the consumer to guide us through this process.

Contents

INTRODUCTION ............................................................................................ 4

MISSION STATEMENT .................................................................................. 4

PROJECT PLAN ............................................................................................ 5

PRODUCT DESIGN SPECIFICATION SUMMARY ................................................... 6

EXTERNAL SEARCH ...................................................................................... 7

INTERNAL SEARCH ....................................................................................... 8

DESIGN EVALUATION & SELECTION ................................................................ 8

DETAILED DESIGN PROGRESS ....................................................................... 10

CONCLUSION ............................................................................................ 12

APPENDIX ................................................................................................ 13

REFERENCES ............................................................................................. 24

INTRODUCTION According to the National Institute of Neurological Disorders and stroke, there are

approximately 4 million Americans living with the effects of stroke(1)

. Many stroke survivors

suffer from weakness (hemiparesis) or paralysis (hemiplegia) on one side of their body affecting

the use of their limbs. Therefore, Myoelectric Robotic Orthosis is medical device that will help

stroke survivors regain the ability of moving their limbs in a rapid amount of time compared with

current physical therapy methods. Basically, this medical device is an exercise machine that uses

advanced technology to detect the voltage signals via Biopotential electrode sensors in the

Electromyography (EMG) Amplifier. In other words, EMG measures muscle response or

electrical activity in response to a nerve’s stimulation of the muscle. Most medical researchers

use EMG to test if muscles and nerves are working correctly(2)

. However, in this project it’s

important to take advantage of the muscle electrical activity and use it as input for the motor.

Therefore, electrical signals will be amplified and used to function the device. Figure 1 shows

the five main processes in the device.

MISSION STATEMENT Designing this medical device will develop the method of integrating technology with physical

therapy. It will help stroke survivors relearn skills that are lost when part of the brain is damaged.

Also, it will help them to become as independent as possible in a rapid amount of time compared

to traditional physical therapy exercises. The ultimate goal is to deliver the final product by the

end of Spring 2014.

PROJECT PLAN Our project plan was created precisely to keep track of all the work and assignments needed

through winter 2014. The project plan consists of breaking up the timeline into three different

phases. As shown in tables 1, 2 and 3 the team is already done with phase 1 and 2 and still

working on the final task in phase 3. However, for spring 2014, our project plan will focus on

phase 4, “Detailed Design Development.” In this phase, a prototype will be built and tested for

range of motion, strength, and ease of use for stroke survivors. Table 4 shows all the tasks

required in phase 4.

- Phase One: Electrical Design

Done Electrical Design Phase Due By

YES Brainstorming And Ideas 1/30/14

YES Electronic Enclosure Detailed Design 1/30/14

YES Integrating Electronic Components 2/6/14

YES Specify Motor, controller and Voltage regulator 2/6/14

- Phase Two: Programming

Done Programming Phase Due By

YES Conceptual Brainstorming 2/13/14

YES Configure Microcontroller program 2/13/14

YES Test the program 2/20/14

- Phase Three: Mechanical Components

Done Mechanical Prototyping Due By

YES Measure Required Torque and speed range for arm 2/26/14

YES Specify Motor Power 2/26/14

YES Specify Gearhead 2/26/14

YES Integrating Programming and Mechanical Phases 3/6/14

Detailed Design Ideas 3/16/14

- Phase four: Detailed Design Development

Done Final Mechanical Assembly Due By

Detailed design Discussion 4/3/14

CAD Model/Solidworks 4/10/14

Generating G-Code 4/17/14

CNC Machining of electronics enclosure 4/24/14

3D print and laser cutting 4/24/14

Machining Rigid Support Frame 5/2/12

Design thermoform mold 5/9/14

Sewing 5/16/14

3D Print thermoform mold 5/16/14

Thermoforming of cuffs 5/23/14

Assembly 5/30/14

Test Prototype 6/1/14 - Refer to Appendix-A for the detailed descriptions of all the tasks and the approximate

amount of time that is associated for each task.

PRODUCT DESIGN SPECIFICATION SUMMARY A Product Design Specification layout was created to act as a guide to design this product.

Electrical and programming designs is complete, therefore the mechanical design components

are the main focus of the updated PDS. From the research and interviews conducted since the

original PDS document, the following summary of the updated design specifications was created.

REQUIREMENTS

Survivor

- Comfort is a luxury, but should be integrated if possible.

- There should be no safety concerns that distract the patient from their mental focus.

- Ease of use will also allow mental focus on the task at hand.

Therapist

- Target multiple muscle groups.

- Device needs to work as good, or better than current technology.

- It will save time and money by allowing patients to use it without assistance.

- The machine needs to be adjustable to perform multiple exercises.

- A wall-mounted design is of preference.

- Exercises should target extension muscles, as well as contraction muscles.

- Level-plane motion (perpendicular to force of gravity) is of importance.

- Exercises should mimic everyday tasks.

- Repetition is a major component of success.

These are all things that are necessary for this product to function in a matter that will be

accepted by and purchased by the therapeutic industry.

EXTERNAL SEARCH There are many methods, devices, and machines being used in post stroke rehabilitation. The

devices and machines that appeared to be affective were too expensive and the affordable options

were already being offered to my grandma.

The existing devices are passive. Passive rehabilitation included devices and methods that assist

the patient through a task or motion without the patient initiating or controlling the movement.

An example of this is a simple range of motion exercise where the therapist holds the patients

arm and physically assists them. Another example is the parallel beams. These are used to assist

the patient in relearning how to walk.

After doing neurological research on the physiology of a stroke, and reading case studies relating

to stroke therapy, the idea for an active therapy device came about. An overview of the findings

from this research can be found in appendix A. An active therapy device means that the patient

initiates the movement and the machine or device assists. The case studies supported this

approach and confirmed that it is more effective in restoring function and greatly reduces overall

recovery time.

The next step was to search for existing active therapy devices. The mPower10003 was

discovered. It is a wearable robotic orthosis developed by MIT. This was the only active

therapy device found.

INTERNAL SEARCH After the arm brace style device was found to be unviable due to patent protection, the capstone

team began brainstorming to generate alternative methods of limb actuation. Three main

concepts were initially explored for the actuation. The first concept involved moving affected

limbs in a similar manner to an adjustable hospital bed. The second was to initiate movement on

a Cartesian plane much like a CNC table. The third movement method was a device comparable

to an exercise machine, where instead of using weights to supply resistance to movement a motor

would be used to assist movement.

In addition to the general concept of movement, system layout was explored. The layout of the

machine is crucial in generating a detailed design. This led to the discovery of four possible

design layouts: wall mounted, table mounted, stationary free standing, and movable free

standing.

Another topic for brainstorming was the components and set up of the electrical system. The

ideas generated for powering the DC motor included an H-bridge and a linear amplifier. It was

found that both would power the motor with less of a delay. To track the movement of the motor,

both potentiometers and encoders were discussed.

After extensive brainstorming, it was necessary to evaluate the ideas produced and make a

selection based on the needs of the system.

DESIGN EVALUATION & SELECTION To evaluate the ideas produced during brainstorming, seven main criteria were used: versatility,

low weight and volume, simplicity, ease of use, low cost, low visibility, and safety.

First, the system needs to be versatile in order to be most useful for patients. If the machine can

perform more exercises and function with more degrees of freedom, then it can help patients to

regain the use of more limbs and joints.

Second, the machine should not be excessively heavy or large. The more compact and

maneuverable the machine is, the more likely it is to appeal to rehabilitation facilities.

Third, the design for the machine should be relatively simple. If the design or manufacture of the

system is too complex, the machine will be less likely to be finished on time for this project,

more likely to have problems, and will probably be more expensive.

Fourth, the ease of use of the machine is crucial. Since the idea is to sell the device to physical

therapy and rehabilitation facilities, the machine will need to be intuitive and easy to use, or the

physical therapists will not want to use it for treatment. Customer satisfaction will also increase

sales. Therefore, this criterion reflects the opinion of the group on ease of use, as well as some

feedback from physical therapists and customers.

Fifth, the device must be low cost. This is important both for the feasibility of completion for this

Capstone project, and for the future manufacture and sale of these machines. The device must be

comparable to or less expensive than existing products, or it will not be useful for customers.

Sixth, the machine should not be too visible or bulky. The user should not feel that they are

hooked to a machine, but rather that they are simply going through the motions themselves. This

is important for the stroke survivors to restore their neurological pathways through the concept or

neuroplasticity.

Finally, safety is imperative. The exercise machine must be safe to use, including the ability to

contain programming and mechanical stops to keep the device from overextending limbs or

otherwise harming the patients. Safety is a high priority and must be addressed in any concept

that is chosen.

Each concept generated during brainstorming was rated in each of these seven criteria. The

rating is weighted and each concept is given a score out of the highest score possible for each

criteria. The total of the rating values was calculated for each concept. The concept with the

highest total was deemed to be most appropriate for the project and was selected. See Table 1 for

the ratings and totals.

Table 1: Concept Evaluation Criteria and Ratings

After applying the evaluation criteria, a decision was made for each category based on the totals

for each concept. The final decision was to develop a pulley exercise machine that can be

mounted on a wall or stationary freestanding. Using these components, the detailed design

process could begin.

DETAILED DESIGN PROGRESS Detailed design encompasses three fundamental areas: electrical, programming, and mechanical.

The initial electrical system prototype used voltage sensors placed on the forearm, a differential

amplifier, an arduino microcontroller and a transistor circuit to drive a servo motor. A power

supply was used to power both the controller and the servo motor. This system proved the

possibility of controlling a motor by sensing muscle voltage changes. However, when the servo

motor was replaced with a DC motor that had sufficient power to move a limb, there was a

perceivable delay between sensory input to motor output. This problem was resolved by using

an H-bridge circuit to drive the motor. The H-bridge and motor are powered by a separate supply

from the Arduino microprocessor, due to electromagnetic interference (noise) issues. Currently

the prototype electrical system drives a geared DC motor without perceptible delay.

Another consideration in the electrical system was position sensing and feedback. The design

options considered were to use an optical encoder to sense the rotational position of the armature

or using a potentiometer attached to either the output shaft of the actuating pulley, or on the

patient’s arm itself. Using a potentiometer to sense motor output shaft position was selected

mainly due to lower cost and simpler design. Using an encoder would add more complex code

and a lot of processing time to the circuit. Since the goal is to minimize the patients’ perceivable

delay, the potentiometer was the best option. Using a potentiometer, changes in position will

change the resistance, which can be measured as a voltage change in the circuit proportional to

angular position.

The microcontroller program currently receives voltage input and converts this signal to voltage

output normalized to the 24VDC input of the motor. Subsequent programming steps will

incorporate a calibration program that will set the resting muscle voltage to zero and set the

limits of motion for the motor. A graphic display will also be used to streamline the interface

between the user and the machine.

The mechanical system is supplied motive power from a 24V brushed DC gear motor. Body

segment mass data and limb movement speed were researched to determine the torque and

angular velocity specifications of the motor. While stepper motors and brushless motors were

initially considered, the brushed motor was selected due to price, simplicity of control, and no

need for fine angular positioning due to the reduction in angular speed through a gearbox. The

purchased motor provides a rated torque and rotational velocity of 31 in-lb and 167 rpm,

respectively, with a keyed shaft for pulley attachment.

Detailed design of the entire assembly which includes an adjustable frame structure, components,

and interface is in progress. The frame consists of a vertical square tube with attachments points

on the top and bottom that can accommodate free standing and wall mount operation. A housing

containing the motor and part of the electronics package will be attached to the tube allowing for

vertical adjustment for patient build and differing exercises. A counterweight system will be

employed to preclude the housing unit from falling to the floor if unclamped. Design of the

EMG sensors and integrated limb attachment point are currently underway and will be the final

step of detailed design.

CONCLUSION The progress of the design is congruent with the goals set in place. A prototype of the

Myoelectric Robotic Orthosis device is complete, but is lacking full functional potential. Goals

were set based on three categories: Electrical, Programming, and Mechanical, and further design

will be addressed Spring 2014. The electrical system currently consists of many discrete and

disconnected parts. The next step in detailed design is to consolidate these separate elements

into an unobtrusive electronic package, and to create versatility in the exercises of the machine.

Although the mechanism works in the simplest form, the functionality of the system needs to be

altered to meet design requirements based on consumer feedback. An adjustable pulley system

will be integrated that allows patients to mimic everyday tasks. The last portion of the

mechanical design is refining the sensor attachment and being more specific about placement of

the electrode pads. A detailed CAD model will be complete by April 10. The final step of the

programming is adding ROM and baseline voltage calibration sequence into the program and

integrating a graphic interface. Furthermore, there have been three major stopping points in this

design process that called for creative decision-making. The necessary decisions made at these

crossroads were the following: Creating a machine that targets multiple body parts and body

motions—as opposed to an arm brace, switching from a servo motor to a DC motor with an H-

bridge to facilitate power, and to have a wall-mounted machine to harness leverage without

compromising floor space. With all these design components in place, the greatest compromise

made is in the optimization of time and money versus functionality. Instead of creating a

machine with a complex system that can do all intended exercises, time and money constraints

lead to a more simple and efficient machine that does most intended exercises.

APPENDIX

Appendix-A [Timeline Schedule] - This table shows the detailed descriptions of all the tasks, and the approximate

amount of time that is associated to each one.

*Number inside boxes indicate number of team members for each task

Task Name Duration June

W1 W2 W3 W4 W5 W6 W7 W8 W9 W10 W11 W12 W13 W14 W15 W16 W17 W18 W19 W20 W21 W22

Electrical

Procurement Lead Time 20 days

Conceptual Brainstorming and Selection 16 hrs Group

Integrating Electronic Components 10 hrs 2

Electronic Enclosure Detailed Design 12 hrs Group

Specify motor controller and voltage regulator6 hrs 1

Total Work 44 hrs

Programming

Conceptual Brainstorming and Selection 10 hrs Group

Configure Microcontroller Program 6 hrs 1

Test the program 1 hr 1

Total Work 17 hrs

Mechanical Prototyping

Procurement Lead Time 15 days

Conceptual Brainstorming and Selection 20 hrs Group

Detailed design 20 hrs Group

Measure required torque range to assist arm30 min 2

Measure required speed range to assist arm 5 min 2

Specify motor power 3 hrs 1

Specify gearhead 3 hrs 1

CAD Model 10 hrs 1

3D print and laser cutting time 36 hrs 1

Assembley 5 hrs Group

Test 2 hrs Group

Design Refinement 10 hrs Group

Total Work 83 hrs

Final Mechanical Assembley

Procurement Lead Time 15 days

Detailed design 10 hrs Group

CAD Model 10 hrs 1

Generating G-Code 3 hrs 1

CNC Machining of electronics enclosure 12 hrs 1

Machining Rigid Support Frame 5 hrs 2

Design thermoform mold 2 hrs Group

Sewing 5 hrs 2

3D Print thermoform mold 10 hrs 1

Thermoforming of cuffs 1 hr 2

Assembley 10 hrs Group

Total Work 41 hrs

January February March April May

Appendix-B [Product Design Specifications]

- This table shows the House Of Quality used in the Product Design Specification

Phase.

Customer Requirements Design Criteria

House of Quality

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Performance

1 Relatively Silent operation 4 +++ + + +++ + · · · · Level of Correlation

2 Brace weight 4 + ++ ++ · + +++ · + · · None

3 moving an average person's arm unassisted 4 ++ +++ · · . · + ++ . + Low

4 range of motion 4 ++ + ++ . + + + ++ + ++ Moderate

5 Calibration setup time 3 ++ + · · . · · ++ ++ +++ High

6 ambidextrous operation 5 · ++ · · . · . +++ ++

7 Intuitive User Interface 4 +

Cost

10 parts <$1000 1 + ++ + +++ + · + · ·

Design Life

10 NA 2 · ++ + ++ + + · · ·

Quality

11 Withstand small impacts 3 + . . +++ . + . . +

12 Operate at full capacity 4 +++ +++ +++ · +++ +++ ++ ++ +

Safety

14 Does not cause injury 5 +++ +++ +++ +++ +++ +++ +++ +++

- This table consists of all the original Product Design Specifications such as:

Performance, Safety, Environment, Ergonomics, Manufacturing and Installation.

Appendix-C [External Search Information]

- An overview of the physiology of a stroke and background on case studies supporting

active therapy.

Physiology of a stroke

Stroke victims suffering from hemiplegia or hemiparesis show functional deficits in voluntary

motor control. All voluntary motor control originates in the brain and the motor cortex is the

area of the brain most involved with voluntary movement.

Even the simplest tasks require many complex sequential and concurrent processes. When you

take a drink of water from a glass, it involves reaching out towards the glass and positioning your

hand so it can grab the glass. Your prefrontal cortex immediately begins preparation for this

movement and transmits the information through a large number of axons projecting from the

parietal cortex, a region involved with spatial perception. Its analysis of the position of your

body and limbs relative to the glass is essential in preparing for the movement. The basal

ganglia are another set of brain structures involved in this part of the process.

The premotor cortex and supplementary motor area work with the cerebellum to specify the

precise sequence of contractions of the various muscles that will be required to carry out the

selected motor action, in this case, raising your arm and extending it forward to grab the

glass. To do this your brain will need to convert the glasses location in the external environment

into a set of intrinsic coordinates allowing precise adjustment of the angles of the joints involved

in the movement.

The primary motor cortex, the brain stem, and the spinal cord produce the contractions of all the

muscles needed for the chosen movement. The primary motor cortex determines how much force

each muscle group must exert, and then sends this information to the spinal motor neurons and

interneurons that generate the movement itself, as well as the postural adjustments that

accompany it.

Neuroplasticity

Neuroplasticity refers to the brains ability to change in response to stimuli from the external and

internal environments. The changes involve individual neurons—for example, synthesis of

different proteins or sprouting of new dendrites—as well as changes in the strengths of synaptic

connections including the neuromuscular junction.

The areas of the brain known to have this capability include the association areas of the frontal,

parietal, occipital, and temporal lobes, and the primary somatosensory and primary motor areas

in the brain.

If a particular body part is used more intensively or in a newly learned activity, such as reading

Braille, the cortical areas of the brain devoted to that body part gradually expand. Memory

occurs in stages over a period of time. Immediate memory is the ability to recall ongoing

experiences for a few seconds. It provides a perspective to the present time that allows us to

know where we are and what we are doing it is related to. Short-term memory is the temporary

ability to recall a few pieces of information for seconds to minutes. One example is when you

look up an unfamiliar telephone number, cross the room to the phone, and then dial the new

number. If the number has no special significance, it is usually forgotten within a few seconds.

Brain areas involved in immediate and short-term memory include the two nuclei of the thalamus

(anterior and medial nuclei). Some evidence supports the notion that short-term memory

depends more on electrical and chemical events in the brain than on structural changes, such as

the formation of new synapses. Information in short-term memory may later be transformed into

a more permanent type of memory, called long-term memory, which lasts from days to years. If

you use that new telephone number often enough, it becomes part of long-term

memory. Information in long-term memory usually can be retrieved for use whenever needed.

The reinforcement that results from the frequent retrieval of a piece a piece of information is

called memory consolidation. Long-term memories for information that can be expressed by

language, such as a telephone number, apparently are stored in wide regions of the cerebral

cortex.

Anatomical changes occur in neurons when they are stimulated. For example, electron

micrographs of neurons subjected to prolonged, intense activity reveal an increase in the number

of presynaptic terminals and enlargement of synaptic end bulbs in presynaptic neurons, as well

as an increase in the number of dendritic branches in postsynaptic neurons. Moreover, neurons

grow new synaptic end bulbs with increasing age, presumably because of increased use.

Mirror Neurons

Scientists studying Area F5 in the ventral premotor cortex of monkeys found that certain neurons

in this area sent out action potentials not only when the monkeys were moving their hands or

mouths, but also when they were simply watching another animal or a human being who was

making such a gesture. These neurons were dubbed mirror neurons because of the way that a

visually observed movement seemed to be reflected in the motor representation of the same

movement in the observer.

In addition to mirror neurons, which are activated both when you perform an action yourself and

when you see someone else performing it, another kind of neurons, called canonical neurons,

become activated when you merely see an object that can be grasped by the prehensile

movement of the hand whose movements they encode—as if your brain were foreseeing a

possible interaction with this object and preparing itself accordingly.

What these two types of neurons have in common is that they are both activated by an action

regardless of whether you are carrying that action out, anticipating carrying it out, or watching

someone else carrying it out.

Many subsequent studies have tended to confirm that mirror neurons exist in the human brain as

well. For example, in a study published in the December 2004 on-line edition of Cerebral Cortex,

a group of professional ballet dancers and a group of dancers of capoeira (a Brazilian

dance/martial arts form) were asked to watch short videos of dancers performing brief ballet and

capoeira moves, while a functional magnetic resonance imaging (fMRI) scanner detected

changes in their brain activity. A control group of non-dancers also participated.

The fMRI results showed that the areas of the dancers’ brains associated with this “mirror neuron

system” were more active when they were watching movements of the kind that they were

trained in than when they were watching the other kind. The non-dancers in the control group

showed even less mirror-neuron activity than the ballet dancers watching capoeira or the

capoeira dancers watching ballet, and this lower level of activity was the same regardless of

which of the two types of dance they were watching.

This study thus not only supports the idea that there is a mirror neuron system in the human

brain, but also shows that this system’s activity level increases with the degree of training that

the individual has in certain particular types of movements. And, it should be stressed, this

increased activity occurs not in the visual centers of the occipital cortex, but in the motor area

where the brain plans complex movements, as well as in the intraparietal sulcus, a brain area

responsible for visual-motor integration.

Action Potential

“Action potential” is the technical term used to describe a nerve impulse. It consists of a brief,

reversible polarization that propagates along an axon. It differs from a receptor potential

(synaptic potential) in several respects.

First of all, an action potential does not propagate passively, but actively, by means of special

voltage-sensitive ion channels in the axon. In addition, mammals have a particular mechanism

that accelerates the propagation of the action potential.

This process also requires energy from the neuron, which must maintain the activity of the ion

pumps that rebalance the charges on either side of the membrane after an action potential has

passed.

Action potentials do not vary in amplitude or intensity. If the intensity of a stimulus falls below

the neuron’s excitation threshold, nothing happens. If the intensity of this stimulus exceeds this

threshold, it does not matter whether it does so by a small or a large amount. Either way, an

action potential will be triggered, and its amplitude and frequency will always be the same for

any given cell. Consequently, the only way a neuron can transmit information is by varying the

frequency of its action potentials. The action potential creates a voltage potential that is

proportional to the force of the contraction and this voltage potential can be measure at the

surface of the skin above the muscle and observed used an EMG.

Evidence Based Rehabilitation Studies

There are several types of post stroke rehabilitation that can be divided into three categories;

pharmacological, behavioral, and cognitive. Behavioral and cognitive are shown to have the

greatest impact in facilitating neuroplasticity.

Behavioral Therapy: Exercise is one of the best behavioral therapies because it has one of the

most significant effects on neuroplasticity. Studies have shown that exercise can have substantial

benefits for brain reorganization, because it stimulates the connections in the central nervous

system. Rehabilitating exercise improves motor skills after a stroke which helps the brain forge

new neural pathways and connections. This facilitates the processes involved in neural plasticity.

Cognitive Therapy: Cognitive rehabilitation focuses on the recovery of functions such as

memory, attention, motor skills, as well as other functions. Depending on the patients care

needs, it can be the most important. It’s the most effective form of therapy for stimulating the

neuroplasticity processes in post-stroke patients due to its direct effects on the cognitive areas in

the brain.

Mental practice is the term given to practicing activities and movements ‘in the mind’, and it has

been used in athletes. Recent studies have shown that it can also be used on stroke patients, who

visualize motor movements through mental imagery, alongside other cognitive-based

treatments. It has been suggested that patients should visualize and practice an activity mentally

in conjunction with other conventional treatments in order to improve motor functions,

especially arm movement. Virtual reality has also been used to improve motor movements

alongside balance.

With regards to fine motor skills, repetition of the same activities every day such as putting on

make-up, picking up and putting down a coin helps to produce new neural pathways in order to

compensate for the damaged pathways, and these exercises can help promote neuroplasticity in

post-stroke patients.

With more strenuous motor movements such as with arm movement, studies have shown that it’s

more beneficial to conduct bimanual exercises opposed to merely exercising the affected arm

alone. Bimanual exercises have also been shown to have a direct effect on promoting cortical

neural plasticity in various ways: motor cortex disinhibition that allows increased use of the

spared pathways of the damaged hemisphere, increased recruitment of the ipsilateral pathways

from the contralateral hemisphere supplementing the damaged corticospinal pathways, and up

regulation of descending premotor neuron commands onto propriospinal neurons.

Conclusion from Research Analysis

Not all of the research data was presented in this report. The following conclusions are

presented in the same order as the sections of data presented. In some cases, conclusions will be

made based on correlations found between sections with an emphasis on neuroplasticity.

• The specific functional deficits observed in someone who has suffered a stroke can be

correlated with the functions of the cortical regions damaged by the stroke.

• The interdependencies that exist between the areas of the brain responsible for the

initiating, coordinating, learning, and remembering voluntary movement in conjunction with

neuroplasticity mean that stimulation of at any point in the loop is an effective way to innervate

new neural growth resulting in healthy brain function in stroke victims.

• The cerebellum uses visual signals associated with movement of limbs to store

information that will improve the coordination of muscle tension and relaxation resulting in

more precise and accurate voluntary movement of that limb.

• The brain releases dopamine during a rewarding experience. The motor cortex

contains dopamine receptors which can form positive associative memories that reinforce the

neuro connections used in the corresponding movement.

• Neuroplasticity is the most important process that should be stimulated in the affected

areas of the brain.

• Visualizing a movement associated with an affected limb is an effective way to stimulate

the areas affected by the stroke thereby initiating the reparative effects of neuroplasticity.

• Cognitive therapy is the most effective form of therapy because it stimulates the

activation of neuroplasticity.

• Neuroplasticity can heal the neural connections damaged by a stroke and restore lost

functionality.

• When the patient initiates a voluntary movement, an action potential in the form of a

voltage differential is created across the appropriate muscle. This voltage change only exists

when the patient initiates movement. The voltage potential is created by sodium and potassium

ions and can be measured quantitatively.

• The threshold of an action potential is dynamic and influenced by the brains

interpretation of visual, tactile, pressure, and force signals from sensory receptors associated

with the movement.

Recommendations

It is our recommendation that the use of EMG activated motorized exercise machine be

implemented and used during all cognitive therapy sessions. When used on the affected limb it

will have a direct impact on the corresponding areas of the cortical region affected by the

stroke. The machine works by sensing the intent to move by measuring and monitoring the

action potential created during a muscle contraction. An EMG amplifier and sensors are used to

take these measurements in real time. At the instant the action potential is sensed, the motor

which is located on the exercise machine above the joint of the affected limb begins to

rotate. The motor spools a cable with an appropriate handle or strap that connects to the affected

limb. The assisted motion can be incremental or continuous through the range of motion. The

visual feedback will stimulate the cerebellum reinforcing the creation of new neuro pathways for

the motion. The result is an increase in restored function compared to passive rehabilitation.

This versatility of this device makes it appropriate for use on the upper and lower extremities of

all stroke victims. The cost of the device is relatively low compared to passive therapy devices

such as electrical stimulation.

REFERENCES

[1] Stroke rehabilitation information. (2013, June 19). Retrieved from

http://www.ninds.nih.gov/disorders/stroke/stroke_rehabilitation.htm

[2] Rash, G. (n.d.). Electromyography fundamentals. Retrieved from

http://people.stfx.ca/smackenz/Courses/HK474/Labs/EMG

Lab/EMGfundamentals.pdf

[3] http://www.myopro.com