(5) GRT

What is grey matter made up of

It’s in the brain and spinal cord and made up of cell bodies

What is white matter made up of

It’s made up of nerve fibers forming tracts

Lower volume of grey matter results from…

Reduced synaptic densities (prefrontal cortex more affected than other regions)

More volume in brain is better

True

Hippocampus deals w

Memory consolidation

Damage in prefrontal cortex causes

Personality change, impulsivity, and pbls w executive function

With age, lateral prefrontal cortex volume declines steadily

True

What does the graph of white and grey matter indicate?

Points show age related volumetric change in lateral prefrontal cortex, visual cortex, and hippocampus (measured w magnetic resonance imaging)

Why does the graph not show that there are not exactly the same declines in executive function?

Bc the brain is not predictive and scaffolding allows the brain to make up for it

The prefrontal cortex volume correlates with (2)

Measures of fluid intelligence AND preservative errors on Wisconsin card sorting task (troubles switching from colour pairing to size pairing)

Synaptic density and aging graph

If u look at synaptic density and there’s 40% loss, then you’ll start showing signs of dementia

Someone w synaptic density at birth will…

Pass dementia threshold earlier than normal ppl bc they already has synaptic density decrease at birth

Someone with normal synaptic reserve will never get dementia bc…

They’ll die before they reach that point bc they wont hit the threshold line until 130 and no one lives that long

If you have AD pathology, there’s a greater decline in synaptic density, meaning…

You will cross dementia threshold at an earlier age than most

White matter integrity (young vs old)

Younger and older ppl have differences in white matter — younger ppl have greater white matter integrity so their brain is brighter in imaging

White matter abnormalities are associated w poor performance in…(4)

Processing speed, executive function and immediate and delayed memory

Age related decreases in frontal white matter coherence are correlated w decreases in (2)

Processing speed and reasoning ability

Older adults who do well cognitively use both sides of their brains more than younger adults and low performing older adults

True

Younger adults use more of their ___ ____ brain

Right lateral

Bilateral activation

Using both sides of your brains (older adults w high performance)

Compensatory activation of the brain

Compensating by using both sides of the brain and showing preserved executive function (older adults w high performance)

Ways to look after your brain to avoid the risk of developing cognitive difficulties (4)

Stay intellectually engaged, maintain cardiovascular physical activity, minimize chronic stress and maintain brain-healthy diet

Staying intellectually engaged (looking after your brain)

Mental activity protects against age related declines and progression to AD, increases baseline level so age related declines begin to affect everyday functioning later in life, and enriched environ stimulates neurogenesis in aged rats (indicating possible mechanism for benefits of cogntiive stimulation)

Maintaining cardiovascular physical activity (looking after your brain)

Exercise, it helps executive functions and reduces declines in tissue density in frontal/parietal/temporal cortex and might have a global effect on brain too

Minimize chronic stressors (looking after brain)

Distress associated to increased risk of AD and faster rate of cognitive decline, increased glucocorticoid levels and could damage hippocampal neurons, cortisol administration reduces glucose metabolism in hippocampus

A lot of stress is systemic

Poor people… lots of ppl dont have access to many things

Maintain brain-healthy diet (looking after ur brain)

High in poly and mono-unsaturated fatty acids, vitamin E and polyphenols and antioxidant — might slow cognitive decline and prevent AD progression

The most important factors at early life to reduce prevalence of dementia

Education

The most important factors at midlife to reduce prevalence of dementia

HEARING, good levels of LDL CHOLESTEROL, no depression, no TBI, physical activity, no diabetes, no smoking, no hypertension, no obesity, no excessive alcohol

The most important factors at late life to reduce prevalence of dementia

SOCIAL LIFE, no air pollution, no visual loss