Dementia Flashcards
How much will the # of centenarians grow by?
500% in 2030
What is the max. number of years a human can live?
~120
What is the overall life expectancy?
- 8 overall
- 4 males
- 2 females
What is the average life expectancy for black males/females?
males 72.1
females 78.2
Hispanic female life expectancy?
live longer than white males
How has the survival curve changed since the 1900s?
Curve has moved to the right-life expectancy has increased over time but max life span has not
What is the cellular theory of aging?
Max. lifespan is predetermined and depends on number of mitotic divisions your fibroblasts undergo in a lifetime
What is the DNA mutation theory?
Aging occurs as a result of changes in DNA and RNA
What are some factors that can cause changes in DNA and RNA?
External factors
accumulation of errors that have occurred over time with transcription
Telomere destruction
What affect does inheritance have on aging?
Many inherited factors contribute to aging
They may affect one system primarily but usually affect multiple systems
What is the oxidative stress theory in regards to aging?
During aerobic metabolism, free radicals are produced as byproducts of using O2. These free radicals affect membranes and mitochondrial function which further accelerates aging
What diseases are associated with Oxidative stress?
Parkinsons (normal breakdown of dopamne leads to free radical formation)
Familial type of ALS
What is the 7th leading cause of death?
Alzheimer’s
5th leading cause in people >65
What is considered “ideal” aging?
1-2% of brain loss/decade for 40-80 year olds
total 6-10% brain loss by old age (>80)
What part of the brain looses volume at a faster rate than the rest?
Hippocampus ~5% a decade, so ~25% by 80 yo
What happens to the cortex and the ventricles?
Decrease in cortical thickness and ventricular enlargement
Where do you see the most profound loss of neurotransmitters and receptors?
See throughout the whole brain but especially in the basal ganglia and prefrontal cortex
Effects of aging on cell bodys?
Cell bodies shrink
What happens to the dendritic tree with aging?
Decreased branching, decreased spines ~(46% decrease in number of spines and density in people >50)
What happens to axon collaterals with aging?
Decreased number of axon collaterals
What are inclusions?
Neurofibrillary tangles
What abnormal structures are found in normally aging brains?
Senile plaques and inclusions albeit at a much reduced number than
What are glial cells active during?
Active in myelinization and transport of nutrients and maintaining homeostasis
Declines in what systems are related to postural control and aging?
Decline in sesory/motor systems
Decline in central processing
Decline in dual task abilities
Two aging hypothesis?
Aging machinery and Negative plasticity