Week 2 Neuroplasticity and Intro to Stroke Flashcards
ACA/MCA Stroke – strength and sensory components are biased to the upper or lower extremity.
MCA – UE is (weaker and less/stronger and more) sensory than LE. ACA – LE is (less/more) affected than UE.
The homunculus – certain parts of the body are represented on the motor and sensory and different parts are supplied by the blood differently. Have to base it on where the blood goes, not the lobe.
Spasticity fatigues out, so to test, have to do PROM (once/a couple times) then you test (immediately/after a couple ROM checks) . Have to test right away, instead of moving the joints around to assess passive range of motion.
ALWAYS DO VITAL SIGNS
Have to go for the big ticket items and if you have time you can get to the maybes.
weaker and less; more; once; immediately
Systems theory is used to describe the process by which various brain and spinal centers work cooperatively to accommodate the demands of intended movements. Both internal factors (joint stiffness, inertia, movement-dependent forces) and external factors (gravity) must be taken into consideration in the planning of movements.
Hierarchical theory, in which control was viewed as proceeding only in a descending, top-down direction from higher to lower centers, with the cortex always in control.
Task-oriented training utilizes challenging and meaningful practice with appropriate feedback in a supportive environment that enhances the effects of interventions. Involved segments (areas of weakness) are targeted for training.
Reflex theory – we as humans move in reflex patterns on a subconscious level. We move on whatever stimulus was given to us.
Got it
Neuroplasticity
Neuroplasticity:
“Ability of the nervous system to respond to intrinsic or extrinsic stimuli by reorganizing its structure, function and connections” (Cramer et. al 2011)
“Possess the remarkable ability to alter their structure and function in response to a variety of internal and external pressures, including behavioral training” (Kleim & Jones, 2008)
Happens at many levels of the CNS (molecular > cellular > behavioral)
Can have a positive or negative impact on recovery
(Intensive, task-oriented/lax, non-task-oriented) practice drives neuroplastic changes within the CNS, which in turn promotes improved movement and functional recovery
Will reorganize itself based on what information is provided to us.
So the brain is moldable based on what information is provided to us. We can influence the brain .. When brain is infarcted we can help change the brain to walk better, talk better, etc.
As a therapist we can negatively impact their recovery as well.
We can induce plastic change with Intensive task-oriented practice. So you want to challenge the person in a task with what the pt struggles with. Grabbing a cup – don’t just give the pt the cup. Do the task a person struggles with!!
Intensive, task-oriented;
What happens when a neuron dies?
Neuron itself (gains/loses) function
Projections to/from the neuron lose some or all function:
Denervation and/or communication
Corticospinal pathway example
Basic pathways will be interrupted/disturbed
loses
Repair S/P Stroke
Repair?
Physiologically, what are plastic changes?
Neuronal regeneration: axonal sprouting
The first month after stroke is an intense period of reorganization of dendritic spine architecture (Krakauer et al 2012)
Collateral sprouting: neighboring normal axons sprout to innervate cells that were previously innervated by the damaged ones
Regeneration molecular program in peri-infarct neurons that is maximally induced one week after stroke, and then plateaus at three weeks after stroke
There is spontaneous recovery of tissues within the first _ months (at the tissue level)
Greatest amount with the _ days (Krakauer and Carmichael 2017)
The process can be enhanced with behavior experiences
Neuronal regeneration – nerve itself doesn’t get better but parts around the nerves start to sprout to makeup for lost function
This process takes time and it doesn’t happen in one day.
A PT can enhance this process. Don’t want pt to bank on spontaneous recovery.
3; 30
The nerve will be cut in the CNS, assume it is going to die, and work around the injury to maintain some semblance of function. Neurons that wire together fire (separately/together).
together
Critical Period After Stroke Study (CPASS): A phase II clinical trial testing an optimal time for motor recovery after stroke in humans (Dromerick et. al 2021)
“We found a similar sensitive or optimal period _ to _ d after stroke, with lesser effects ≤30 d and no effect _ months or later after stroke. These findings prospectively demonstrated the existence of a sensitive period in adult humans. We urge the provision of more intensive motor rehabilitation within 60 to 90 d after stroke onset.”
When someone has an injury to the brain there is a sensitive period where the brain has the chance to remodel the most. In humans when you have an injury to the brain, people get better within the first 60-90 days. Push the envelope in intensive motor rehab within those 60-90 days which is where they will see the most recovery from their injury.
60; 90; 6;
The earlier on someone starts their rehab process, the (lower/higher) chance they have to recover that function. If they just lay in bed for 6 months, they may or may not get better. The PTs are the ones that have to drive home that message.
higher;
Coo
Coo
Don’t consider just stroke or brain injury, but with all patients – how are you setting them up for positive neuroplastic changes.
All of these factors play a role in designing a therapeutic intervention.
Stroke pt wants to get better at walking – the intervention you give them is based on these principles !
Be as specific as possible. If someone wants to get better at walking, walk! Wanna get better at negotiating stairs, do stairs!
Reps reps reps to induce plastic changes.
Intensity – have to force a challenging task in order to get better!!! Have to force and challenge them.
Time matters – start rehab process ASAP.
Salience – has to be important to the pt even if it is not important to you. Pt has to want to get better at the activity to induce the best changes.
Dr. Bens fav principle
Transference – the ability to transfer a skill to a different environment – standing up from a chair, from a floor, from a sofa
Interference – sometimes your best efforts interferes with other tasks.
Got it
NOT A NUMBERS PERSON FOR THE EXAM
NEED LOTS OF REPS!!!!!! Walking 20 feet (will/won’t) yield the same result as walking 2000 feet.
won’t
The gold standard for measuring intensity is oxygen consumption – (VO2max/HR)
Have to challenge someone! To decide if it is challenging, have to look at metabolic outcome
VO2 max is the gold standard
RPE scale – way to measure intensity if HR is not a viable source of information.
VO2max
Can you recover the lost function?
Neuronal – can the neural tissue regenerate or do other parts of the brain have to compensate?
Impairment – can you regain or recover the strength that is lost or the ROM that is lost or do you compensate?
Bad to compensate on the impairment level – compensation might be a short term solution with a negative long term impact.
Activity – can the activity be recovered without a compensatory mechanism? Can they stand with the appropriate technique or do they compensate by using ADs?
Got it
Motor Learning
Motor learning involves
significant amount of practice
Feedback
Use of (active/passive) learning
high level of information processing related to control
error detection and correction
Patient problem solving
Relatively intact basal _____ and (cerebrum/cerebellum)
Stages of learning
(Cognitive > associative > autonomous / associative > autonomous > cognitive)
In order to learn a skill you need practice and a lot of feedback early on.
As you learn a new skill, you’ll need a lot of feedback and instructions on what to do.
Associative learning – you can do some of it on your own but need some reinforcement
Error detection – have to realize you made a mistake in the first place. Cerebellum and basal ganglia are the two main structures that play a role in this.
active; ganglia; cerebellum; Cognitive > associative > autonomous
Got it
Got it
Resolution of edema
Resolution of ischemic penumbra
Resolution of remote diaschisis
The release of excess neurotransmitters (e.g., glutamate and aspartate) produces a progressive disturbance of energy metabolism and anoxic depolarization, which results in an inability of brain cells to produce energy, particularly adenosine triphosphate (ATP). This is followed by excess influx of calcium ions and pump failure of the neuronal membrane. Excess calcium reacts with intracellular phospholipids to form free radicals. Calcium influx also stimulates the release of nitric oxide and cytokines. Both mechanisms further damage brain cells. (595)
A stroke is death of tissue within the _____ or spinal ____.
Embolic – an infarct where the blood that supplies those tissues doesn’t get there
Hemorrhagic – thinning of the blood vessel wall and can sustain the pressure and blood hemorrhages.
brain; spinal;
Sensation, strength, impaired coordination, etc are impairments
What impairment someone develops depends on what part of the brain is affected. Where is the blood supply going? What does the lobe do? Have to know the anatomy.
Broca’s Area - (Expressive/Receptive) language
Primary motor cortex - (M1/S1)
Primary sensory cortex - (M1/S1)
Wernicke’s Area - (Expressive/Receptive) language
Visual cortex - (speech/visual)
Expressive; M1; S1; Receptive; visual
Synergy Patterns
What do you remember about synergy patterns?
Term to describe (active/passive) movement
Can exist with or without spasticity
Can be present in just one limb
Flexor in UE may be present with Extensor pattern in LE
Common thread is to (work in/work out of) that pattern - If I have extensor based abnormal synergy – promote some element of (flexion/extension).
People with strokes develop synergy patterns –
Synergy patterns – we as able body humans move in the path of least resistance to be as efficient as possible. People with strokes that develop weakness or impaired coordination move with abnormal synergies.
A synergy pattern is an active phenomenon.
Synergy patterns can present in more than one limb and are usually on the (ipsilateral/contralateral) side. Right MCA stroke – (right/left) sided synergy patterns.
active; work out of; flexion; ipsilateral; right;
UE Flexor Synergy
Scapula (Protraction/Depression / Retraction/elevation)
Shoulder (IR/Adduction / ER/Abduction)
Elbow (flexion/extension)
(Pronation/Supination)
Stereotypical patterns of someone with a stroke may present with.
The brain is trying to solve a problem and it is solving it in a bad way.
These are the components within the flexor synergy in the UE.
At rest this person doesn’t have this pattern, it is an active pattern.
Retraction/elevation; ER/Abduction; flexion; supination
UE Extensor Synergy
Scapula (Protraction/Retraction)
Shoulder (IR/Adduction / ER/Abduction)
Elbow (flexion/extension)
(Pronation/Supination)
Stereotypical patterns of someone with a stroke may present with.
Ben has only seen one UE extensor synergy in 5 years
Protraction; IR/Adduction; extension; pronation