What are the three main functional divisions of the nervous system?
Sensory (afferent), Integrative, and Motor (efferent) divisions.
Define neuroplasticity and its importance in recovery.,
The ability of the brain to reorganize and form new connections after injury or experience, enabling functional recovery.
Differentiate upper and lower motor neuron lesions.
UMN lesions: spasticity, hyperreflexia, Babinski sign. LMN lesions: flaccidity, atrophy, fasciculations.
Which vitamin deficiency leads to neural tube defects?,
Folic acid deficiency.
Name two common neural tube defects.
Spina bifida (caudal neuropore fails to close) and Anencephaly (cranial neuropore fails to close).
Explain the Monro–Kellie doctrine.
Brain, blood, and CSF volumes are fixed within the skull; increase in one raises ICP unless compensated by reduction in another.
Differentiate primary and secondary brain injury.
Primary: immediate mechanical damage; Secondary: delayed effects like ischemia, edema, excitotoxicity.
What is diffuse axonal injury?
Widespread axonal shearing due to rotational acceleration, often leading to coma
Define ischemic vs hemorrhagic stroke.
Ischemic = vessel blockage; Hemorrhagic = vessel rupture causing bleeding.
What is the ischemic penumbra?
Viable tissue surrounding infarct that may recover if reperfused quickly
What imaging distinguishes stroke type?
Non-contrast CT scan.
When can tPA be given?
Within 4.5 hours of ischemic stroke onset if no contraindications
What are symptoms of MCA stroke?
Contralateral face/arm weakness, aphasia (dominant side), neglect (nondominant side)
Define spasticity.
Velocity-dependent increase in tone from loss of corticospinal inhibition
Why is early rehabilitation important after stroke or TBI?
Prevents secondary complications and enhances neuroplasticity for motor recovery
Apraxia
Inability to perform purposeful movements despite intact strength
Ataxia,”Loss of coordination from cerebellar dysfunction.”
Dysmetria,”Inability to control range of movement, leading to overshoot or undershoot.”
Abulia,”Lack of motivation or initiative from frontal lobe dysfunction.”
Hypotonia,”Decreased muscle tone.”
Hypertonia,”Increased muscle tone, as in spasticity or rigidity.”
Rigidity,”Increased tone independent of velocity; seen in extrapyramidal disorders.”
Flaccidity,”Loss of tone and reflexes due to LMN damage.”
