brain damage and neuroplasticity

Question 1

what are the 3 different terms for brain damage?

Answer 1

brain damage, disease, injury (terms are not interchangeable but have strong physiological connections)

Question 2

congenital brain injury =

Answer 2

genetic factors affecting neurodevelopment, prenatal/birth related trauma

Question 3

acquired brain injury =

Answer 3

silly things we do to ourselves, can be traumatic or non-traumatic and closed vs open head

Question 4

what range of non-traumatic head injury conditions are there?

Answer 4

stroke, infections, tumours, hypoxia/anoxia

Question 5

what are the 2 main causes of a stroke?

Answer 5

cerebral haemorrhage, cerebral ischaemia

Question 6

bleeding/leaking in the brain that often results from an aneurism =

Answer 6

cerebral haemorrhage

Question 7

blockage of the brain =

Answer 7

cerebral ischaemia

Question 8

why is blood leaking into the brain bad during a cerebral haemorrhage?

Answer 8

blood is toxic to neural tissue as it sucks the water/content out of cells

Question 9

how can you prevent the bursting of an aneurism?

Answer 9

maintain low BP, avoid strenuous activity

Question 10

how does cerebral ischaemia lead to excitotoxicity and neuronal cell death?

Answer 10

interruption of blood supply to part of brain due to blockage of blood vessel. this causes a lack of O2 and glucose to brain area so it dies

Question 11

what is the treatment goal for cerebral ischaemia?

Answer 11

reopen blocked blood vessel

Question 12

what causes blockage of blood vessels?

Answer 12

thrombus, embolism, atherosclerosis

Question 13

tissue in surrounding region of brain that is salvageable from stroke =

Answer 13

penumbra

Question 14

why is treating a stroke quickly vital?

Answer 14

because core tissue that is deprived of O2 is harder to save

Question 15

what are some features of traumatic brain injury?

Answer 15

something sudden and bad happens, can be specific or widespread, directly or indirectly affect brain tissue by damaging the circulatory system, closed or open head

Question 16

what is another name for traumatic head injury?

Answer 16

intracranial injury

Question 17

what is the difference between closed and open head injury?

Answer 17

closed = no penetration to skull. open = skull doesn’t remain intact, object enters brain.

Question 18

what protects the brain when forces are applied to the skull?

Answer 18

cerebrospinal fluid > cushions

Question 19

what causes damage during an open head injury?

Answer 19

bone fragments damage brain tissue, bleeding, infection, swelling

Question 20

what are some of the brain effects of ageing?

Answer 20

decline in cognitive function, structural and functional brain changes, reduction in brain tissue volume

Question 21

powerful risk factor for many brain diseases =

Answer 21

ageing

Question 22

each case has its own origins (no single cause) =

Answer 22

idiopathic disease

Question 23

loss of single type of neuron in specific brain region, motor related symptoms, loss of dopamine NT = what neurodegenerative disease?

Answer 23

parkinson’s

Question 24

how more common is Parkinson’s in men than women?

Answer 24

x2.5

Question 25

what are some of the symptoms of Parkinson's?

Answer 25

movement insufficiency, bradykinesia (slow movements), akinesia = no movements, increased rigidity, resting tremor, shuffling gait, flexed posture, impaired balance

Question 26

what causes Parkinson's

Answer 26

lack of dopamine in nigrostriatal dopamine pathway within the basal ganglia, dopamine deficiency in the striatum

Question 27

explain the frozen addicts story that helped researchers understand Parkinson's disease

Answer 27

bad batch of heroin with by product MPTP. when in brain converted to neurotoxic MPP+ > kills dopamine cells in striatum. heroin users ended up with P.disease. MPTP specifically targets dopamine producing cells. magic bullet > used to recreate the disease > look at pathology, causality and treatments

Question 28

what animals did MPTP have no effect on?

Answer 28

rats, cats, dogs (only non-human primates)

Question 29

what causes Parkinson's symptoms?

Answer 29

excessive output from basal ganglia

Question 30

what is the aim of parkinson's treatment?

Answer 30

to stop the basal ganglia from being stuck on inhibition mode

Question 31

what are the different treatments for P.disease?

Answer 31

surgical intervention, replace lost dopamine, deep brain stimulation, replace lost DA cells

Question 32

what part of the basal ganglia is lesioned to reduce P.disease symptoms?

Answer 32

globus pallidus

Question 33

when replacing the lost dopamine to treat P.disease why can't we just give dopamine?

Answer 33

doesn't cross the blood brain barrier (have to increase precursors and agonists of dopamine)

Question 34

electrical stimulation of basal ganglia to inhibit input to control tremors an chronic movement disorders =

Answer 34

deep brain stimulation

Question 35

chronic persistant disorder of the mental health process caused by brain disease or injury, marked by memory disorders, personality changes and impaired reasoning =

Answer 35

dementia

Question 36

disease that causes dementia =

Answer 36

Alzheimer's disease

Question 37

what is the incidence for Alzheimer's: __% over 65 __% over 85

Answer 37

10, 35

Question 38

what are the symptoms of Alzheimer's disease?

Answer 38

memory loss, selective memory decline, attention deficits, personality changes

Question 39

what are the intermediate states of Alzheimer's disease?

Answer 39

confusion, anxiety, irritability, depression

Question 40

what is the final stage of Alzheimer's that makes it a progressive disease?

Answer 40

swallowing and bladder control

Question 41

what assessment is used for Alzheimer's?

Answer 41

MMSE

Question 42

MMSE scores _____ with age

Answer 42

decrease

Question 43

what is the pathology of Alzheimer's?

Answer 43

enlargement of fluid filled spaces, amyloid plaque deposition

Question 44

what are the plaques made of that cause Alzheimer's?

Answer 44

aggregated lumps of amyloid proteins

Question 45

where do amyloid plaques come from?

Answer 45

amyloid precursor proteins sit across cell membranes > enzymes chop them up > sections of beta amyloid clump together > form plaques

Question 46

what are the 3 genetic risk factors for Alzheimer's disease?

Answer 46

excessive APP , apoE E4 allele, TAU

Question 47

on what chromosome is the amyloid precursor protein found?

Answer 47

chromosome 21

Question 48

if you have the gene for APP by what age will you develop AD pathology?

Answer 48

by 40 years old (early onset)

Question 49

there are 3 versions of alleles E2, E3, E4. the bad version E4 is involved in what?

Answer 49

transport of cholesterol

Question 50

MAPs =

Answer 50

Microtubule Associated Proteins

Question 51

what is the MAP that gets tangled up and is a genetic risk factor to Alzheimer's?

Answer 51

Tau

Question 52

what is the main drug treatment for Alzheimer's?

Answer 52

cholinesterase inhibitors

Question 53

what is cholinesterase and how do cholinesterase inhibitors work?

Answer 53

cholinesterase (Ache) = enzyme that breaks down acetylcholine and prevents it from further acting on neurons. the inhibitor inhibits Ache to increase acetylcholine effect on neurons.

Question 54

what are common consequences of strokes?

Answer 54

amnesia, aphasia, paralysis, coma

Question 55

area of dead/dying tissue produced from a stroke =

Answer 55

infarct

Question 56

produces a thrombus blocking blood flow =

Answer 56

thrombosis

Question 57

produces an embolus that is carried from a larger vessel when formed to a smaller vessel where it becomes lodged =

Answer 57

embolism

Question 58

walls of blood vessels thicken and channels narrow and narrowing can eventually lead to complete blockage =

Answer 58

arteriosclerosis

Question 59

why is there little evidence of brain damage soon after a temporary cerebral ischaemic episode?

Answer 59

ischaemia induced brain damage takes a while to develop. substantial neuron loss can be detected 1/2 days later

Question 60

what area of the brain are neurons particularly susceptible to ischemia induced brain damage?

Answer 60

hippocampus

Question 61

what is released that kills neutrons during the ischemia induced cascade of events?

Answer 61

glutamate

Question 62

how does glutamate kill neurons?

Answer 62

blood vessel blocked > neurons affected by schema release excessive glutamate > it binds to NMDA receptors > trigger influx of calcium and sodium ions into postsynaptic neurons > influx kills them and triggers more release of glutamate > spreads toxic cascade

Question 63

closed head injuries that involve damage to the cerebral circulatory system and produces internal haemorrhaging =

Answer 63

contusions

Question 64

what do contusions result in?

Answer 64

a hematoma

Question 65

localised collection of clotted blood in an organ/tissue (like a bruise) =

Answer 65

hematoma

Question 66

how do contusions occur?

Answer 66

when the brain slams against the inside of the skull causing blood to accumulate in the subdural space

Question 67

injuries that occur on the side of the brain opposite the side struck by the blow =

Answer 67

countrecoup

Question 68

what chemical alleviates symptoms of PD?

Answer 68

injections of L-dopa

Question 69

why is L-dopa not a permanent solution?

Answer 69

typically becomes less effective with continued use

Question 70

Alzheimer's is ______ and _______

Answer 70

progressive, terminal

Question 71

what are the 3 defining characteristics of Alzheimer's disease?

Answer 71

neurofibrillary tangles, amyloid plaques, neuron loss

Question 72

animals into which genes of another species have been introduced =

Answer 72

transgenic