Ch16 Brain Injury and Neuroplasticity Pt1 Flashcards
What is considered traumatic brain injury?
Mechanical trauma to the brain
What is an example of a traumatic brain injury?
A car accident, the head smashing into a rigid object
What types of injuries can result from traumatic brain injuries?
Bleeding, hypoxia, anoxia, and shearing of axons
What is a coup?
A brain injury that occurs at the site of impact
What is a contre-coup?
A brain injury that occurs as the brain rebounds and collides into the opposite side of the skull. The injured portion of the brain is typically opposite the side of initial impact
What are focal injuries?
Injuries to specific regions of the brain
What are diffuse axonal injuries?
When rotational forces shear the axons within the myelin sheet
Diffuse axonal injuries can result in what?
Shaken baby syndrome. Numerous brain regions are affected due to shaking.
What can happen if the brain rotates or slides within the skull?
The sharp bony projections at the bottom of the skull can cut or shear the nearby axons
What is hypoxia?
Decreased oxygen to the brain
What is anoxia?
No oxygen to the brain
How long can neurons survive without oxygen?
About 3 minutes, they have a high metabolic rate
How do injured or dying neurons react?
By swelling
If a neuron is severely injured enough, what happens?
The cell body can rupture
After brain injury, dead and dying neurons release chemicals that can damage adjacent neurons and magnify the initial infarct. True or false.
True
Injury to small blood vessels in the brain can result in what?
Anoxia, pooling of blood, and immune response
What is encephalopathy?
Swelling and inflammation of the brain often caused by infection of the brain or spinal cord, for example bacterial meningitis
When axons are injured, they degenerate back to the neuron cell body. True or false.
True
Can neurons in the CNS regenerate?
No
Can neurons in the PNS regenerate?
Usually, yes
Brain injuries often result in what two levels of impaired consciousness?
Coma and vegetative state
What is the patient like during a coma?
Has eyes closed, is unaware of environment
What is the patient like during a vegetative state?
Has eyes open, is unaware of environment
What is the patient like with a minimally conscious state?
Has some limited awareness of environment
What are the mechanisms of CNS recovery?
Axonal sprouting, activation of parallel pathways, neurogenesis
What is axonal sprouting?
When healthy axons (near damaged axons) sprout new axons
Axons traveling through the damaged region and synapsing with target cells allows for what?
Some motor and sensory recovery
What is activation of parallel pathways?
When intact neurons take on new functions
New synapses are formed that allow a healthy neuron to perform the “job” of a previous (now dead) neuron. True or false.
True
Where does synaptogenesis occur?
In the hippocampus and olfactory epithelium
More new neuron connections are formed in people who remain doing what?
Physical activity and mental stimulation
What are some effects of exercise on functional recovery?
Increased blood supply to the brain, number of neurons in hippocampus, number of neurons in the frontal and temporal cortex
Increased number of neurons in the frontal and temporal cortex can result in what?
Improved memory, concentration, and synaptic connections
Exercise has shown to improve brain function and recovery of those with what diseases?
Amyotrophic Lateral Sclerosis (ALS), parkinson’s disease, stroke, and traumatic brain injury
Neuroplasticity is the mechanism that allows the brain to reorganize itself and therefore allowing what?
Synaptogenesis and neurogenesis
In therapy and functional recovery, “forced use” is what?
Promoting the use of the “affected side”
What is an example of “forced use”?
“Forcing” a left hemiplegic patient to use the left arm for functional tasks
“Forced use” can result in what?
Clinically significant functional recovery
