Module 8: Brain Dysfunction and Neuoroplasticity Flashcards
TUMORS:
Describe different types of brain tumors (3) and explain the difference between an encapsulated and an infiltrating brain tumor.
1) Meningiomas:
- Grow between the Meninges, the three membranes that cover the Central Nervous System.
- All are Encapsulated tumors (grow within their own membrane)
- Almost always Benign tumors (surgically removable w/o further risk)
2) Gliomas:
- Develop from glial cells.
- Are Infiltrating tumors (grow through surrounding tissue)
- Are Malignant tumors (difficult to remove/destroy completely - if any cancerous tissue is left they tend to continue to grow).
- Metastatic tumors:
- Spread through blood from 1 organ to another.
CEREBROVASCULAR DISODERS:
Describe differences between the 2 types of stroke: cerebral hemorrhage and cerebral ischemia.
1) Cerebral hemorrhage:
- Occurs when a cerebral blood vessel ruptures and blood seeps into the surrounding neural tissue and damages it.
- Cause: Usually bc of Aneurysms; balloon-like dilation that forms in the wall of an artery at a point where the elasticity of the artery wall is defective. Can be congenital (present at birth).
2) Cerebral ischemia:
- A disruption of the blood supply to an area of the brain.
- Causes:
1. Thrombosis: a plug is FORMED, can be blood clot, fat, oil, tumor, etc. that blocks blood flow.
2. Embolism: a plug is CARRIED to smaller blood vessel (a Thrombus that has taken a trip).
3. Arteriosclerosis: walls of blood vessel thicken, usually bc of fat, and can lead to complete blockage.
CLOSED HEADED INJURIES:
Describe the 2 sorts of closed-head traumatic brain injuries (TBIs).
1) Contusions & Concussions:
- When the brain slams against the inside of the skull.
- Causes damage to cerebral circulatory system. Can lead to internal hemorrhaging and lots of blood in the brain.
2) Chronic Traumatic Encephalopathy (CTE):
- Dementia and Cerebral scarring, common in sports-players.
- Usually a result of many consecutive mTBI (mild) such as concussions.
INFECTIONS:
Describe 2 different types of infections of the brain.
Infections cause brain swelling - or Encephalitis.
1) Bacterial infections:
- Causes pockets of pus in the brain - Cerebral Abscesses
- Can be treated with antibiotics but Brain damage cannot be reversed
- Ex: Syphilis.
2) Viral infections:
- Can either attack neural tissue or have affinity for it.
NEUROTOXINS:
Describe 3 different types of neurotoxins.
1) Lead - Toxic Psychosis
2) Antipsychotic drugs - Tardive Dyskinesia (TD)
3) Endogenous stress hormones: Cortisol - brain damage.
GENETICS:
Discuss the symptoms of Down syndrome and what causes this disorder.
Cause: Extra 3rd chromosome 21 is created in the egg.
Symptoms: characteristic disfigurement, intellectual disability, early-onset Alzheimer’s disease, etc.
GENETICS:
Explain the difference between apoptosis and necrosis.
1) Apoptosis:
- Neurons and other cells have genetic programs for destroying themselves.
(Useful to get rid of extra neurons, but can also cause brain damage.)
2) Necrosis:
- Passive cell death resulting from injury.
- Brain injuries can cause both!
- Apoptosis is ‘better’ in that there is no inflammation and damage is kept to a minimum bc it takes a few days for it to happen. Necrosis however is immediate.
NEUROLOGICAL DISEASES:
Define epilepsy; describe four common types of seizures; and discuss some treatments for epilepsy.
Epilepsy:
- Patients whose seizures are repeatedly generated by their own chronic brain dysfunction.
Types of seizures:
1) Focal Seizures: does not involve the whole brain
a) Simple Seizures:
- Mainly 1 sort of sensory or motor symptom or
both.
- Usually do NOT involve loss of consciousness
b) Complex Seizures:
- Happens in Temporal lobe
- Patient engages in compulsive, repetitive, simple behaviors commonly referred to as Automatisms
(e.g., doing and undoing a button) and in more complex
behaviors that appear almost “normal.”
- There IS a disruption of consciousness - many report confusion and no recollection of their actions.
2) Generalized Seizures: involves the whole brain
a) Tonic-Clonic Seizures:
- Symptoms include; loss of consciousness, tonic-clonic convulsions (can lead to biting tongue or peeing oneself), and hypoxia (of which can cause brain damage.)
b) Absence Seizures:
- Symptoms include: loss of consciousness with vacant look.
Some Treatments: anticonvulsant meds, ketogenic diet, brain surgery.
NEURODEGENERATIVE:
Describe the symptoms of multiple sclerosis (MS) and its risk factors.
MS:
- a progressive disease that attacks
the myelin of axons in the CNS.
- there is also a lack of re-myelination.
Symptoms:
- visual disturbances, muscular weakness,
numbness, tremor, and ataxia (loss of motor coordination)
Risk factors:
- Vitamin D deficiency
- Exposure to the Epstein-Barr virus (the most common cause of mononucleosis)
- Smoking
NEURODEGENERATIVE:
Describe the symptoms of Alzheimer’s disease and evaluate the amyloid hypothesis.
Two major neuropathological symptoms of Alzheimer’s
disease are Neurofibrillary tangles and Amyloid plaques.
+ All four different gene mutations that cause early-onset Alzheimer’s disease influence the synthesis of beta-amyloid.
- Many people without observable dementia carry
significant loads of amyloid plaques.
Describe the concept of “cognitive reserve,” and discuss the potential role of adult neurogenesis in recovery following CNS damage.
Cognitive reserve:
When observed improvement does not occur because patients have recovered lost brain function, but because their cognitive reserve allowed them to accomplish tasks in alternative ways.
Nerve Maps of a phantom limb for example, can move to other parts of the body - if you touch a left arm amputee’s face, they may feel it in their amputated limb.
Discuss methods of promoting recovery from CNS damage through rehabilitative treatment.
1) Strokes:
- Constraint induced therapy:
Tie down functioning arm for 2 weeks while the affected arm received intensive training. Performance of the arm increases within 2 weeks.
2) Phantom limb pain:
- Using the phantom limb as if it were there can reduce pain!
What are the 6 main causes of Brain Damage?
1) Brain tumors
2) Cerebrovascular disorders (strokes)
3) Closedhead injuries
4) Infections of the brain
5) Neurotoxins
6) Genetic factors.
Describe thee steps of Post Injury Neuroplasticity (4)
1) Cell Dysfunction/Cell death
- Swelling, inhibition of axon growth, metabolic depression
2) Cell genesis
- Gliogenesis, Neurogenesis, Angiogenesis (new blood cells)
3) Adaptive Plasticity
- Synaptogenesis, Functional plasticity and Network relearning
4) Therapies/Interventions
- Constraint induced therapy, Cortical/Deep brain stimulation therapy
