Brain Health and Aging

Question 1

dementia:
1. type and demographics
2. risk
3. plasticity
4. plasticity in older adults

Answer 1

1. higher in females for Alzheimer’s, males higher risk of vascular dementia; having both is mixed dementia
2. 40% of risk related to lifestyle, risk between genetic disposition and inactive no genetic disposition is comparable with lower risk assoc with active no genetic risk
3. increased plasticity by increasing blood flow (angiogenesis) for neurons (neurogenesis) and increasing synapses between existing neurons (synaptogenesis) offsets atrophy
4. plasticity helps older adults maintain processing efficiency by gen alt pathways (brain reserve) for info to pass through so if one area atrophy, info can pass through another pathway; high functioning older adults adopt more brain regions (diverging pathways) to complete a task comp young people; older adults w/o plasticity use same pathway as young, if atrophy then impairment

Question 2

cognitive decline:
1. overview
2. trajectory of decline
3. measuring decline
4. decline in hippocampus

Answer 2

1. cog ability decline of memory, executive functions (PFC fully form at 25 so peak for 5 yrs), and processing speed after 30, whereas other aspects such as world knowledge and vocab continue to dev
2. trajectory (deg) of decline depends on lifestyle choices, poor choices lead to greater risk of other health conditions further increasing risk of cog falling below functional threshold and accumulation of free radicles which put oxidative stress on body by taking e- from brain tissue, killing neurons
3. Montreal cognitive assessment is series of activities to test visualspatial and executive function (order, draw, understand spatial qualities, memory etc), healthy score >=26, moderate cognitive impairment is between 18-26, dementia is lower than 18; people with lower education and don’t speak English score lower, so test scores can be modified for diff pop
4. centre of learning and short term memory, decrease by 0.5% normally, severe atrophy (x8) in Alzhemier’s, has a backup supply therefore less effected by vascular dementia

Question 3

sitting and dementia risk
1. overview
2. decreasing sitting

Answer 3

1. increases blood pressure and decrease metabolism, high BP causes small vessels feeding brain to clog, decreasing BF to brain causing small vessel disease, decreasing brain func esp frontal lobe, white matter deteriorate and decrease speed of function and functions, causing dementia; why vascular dementia patient often exp impaired executive func such as lack of inhibition, planning, etc
2. shorter and more frequent movement breaks increase brain BF more than prolonged sitting or longer but less frequent exercise breaks; exercise breaks maintain attention and focus more than non-exercise breaks and no breaks