L06 - Meditation & Aging Flashcards
(25 cards)
Changes in function with age
RT & Accuracy
Reaction time increases
Effects on accuracy occur later
exception is vocabulary (as well as general knowledge/trivia)
Aging and Cognition
Education
people with high education test similar to young and low education
Age related changes to the brain
cortical atrophy (fewer cells, connections)
- thickness decreases
- volume decreases
- surface area decreases
neurotransmission
activity imbalances
Areas of brain susceptible
parts of frontal, parietal, and temporal
superior, middle, and inferior frontal gyri
superior and middle temporal gyri
precuneus, inferior, and superior parietal cortices
temporo-parietal junction
thinning of temporal cortex is especially concerning for cognition
Accelerated thinning in _____ is associated with future cognitive impairment
temporal cortex
Thinning is a predictor of ________
future disease
Certain amount of cortex may be required to maintain performance
brain reserve theory
excessive cortical thinning may exhaust the reserve and lead to cognitive impairment/disease
we view performance as the result of cognitive processes
cognitive reserve theory
Meditation and brain with age
Grey matter
Glucose metabolism
meditators do not appear to have larger brains, but may show slower gray matter decline with age
glucose metabolism declines with age, but, the decline is less significant in meditators
- effects strongest in the vmPFC, pCC, and insula
___ is a risk factor for cortical thinning
chronic stress
- effect particularly notable in psychiatric disorders
- hippocampus sensitive
- by reducing stress and/or improving mood, meditation might affect brain structure
meditation might affect brain structure by improving sleep or cardiovascular function over time
Raven’s progressive matrices
non-verbal test of fluid intelligence
often used in IQ assessments
performance normally declines w/ age, decline is less evident in meditators and yogi
Limitations
cognitive theories
hyper-fixation on brain reserve within most studies, less consideration of cognitive reserve
despite the fixation upon brain reserve theory, few studies actually correlate brain with behavior
studies report both positive and negative associations (more gray matter and less gray matter)
The Age-Well RCT
no effects on brain structure/perfusion but higher global composite score
Throughout our lifetime, our cells maintain themselves via ____
each time a cell duplicates, the DNA inside must be copied
cells can only divide a finite number of time
replication (mitosis)
When DNA is copied during division, ______
telomeres are lost instead of valuable DNA
Telomeres progressively shorten with cell division, with some maintenance by _______
telomerase
Telomere length as a predictor
inversely correlated with risk for coronary disease, dementia, psychiatric disorders, & cancer prognosis
generally reduced by stress
Meditation’s effect on telomerase
meditation may enhance telomerase activity but tends not to affect telomere length
Caveats
telomeres/dna
most studies examine WBC -> unknown if telomeres in neurons respond similarly
no direct association between telomeres and neuronal function
DNA is ‘packaged’ in a particular way (tightly coiled, wrapped up and surrounded by other structures)
& how does it change
DNA methylation
packaging changes with your experiences, including those that come with aging
modifications in DNA function that occur without changes in DNA sequence
epigenetics
increased methylation in DNA as we age
predictor of aging - more methylation = faster aging
Effects of Meditation on Methylation
meditators show a similar change in
DNA methylation with aging to controls
i.e. no meditation effect on methylation
___ is a disorder marked by memory impairment, personality changes and impaired reasoning
most common form is ____
dementia; AD
Neural features of AD
neuronal loss
NFT
Amyloid-B accumulation
reduced cholinergic tone
