☆ L6: Meditation and Aging ☆ Flashcards
Describe how the age demographics of our population are changing. What are the implications of these changes?
Growing elderly population
Describe how memory and cognitive processes change with age.
Most functions peak at age 20 and decline afterward. Decline is particularly significant after age 60.
Effects on processing speed emerge first. Reaction time increases even when accuracy is unchanged
(higher RT = lower accuracy)
Exceptions to this trend are vocabulary and general knowledge and trivia which increases from ages 20 to 60
How is education associated with cognitive changes in aging?
Educated individuals have a “younger brain”
Describe the effects of aging on the cortex. What areas of the brain are particularly vulnerable?
Aging is associated with gradual thinning of the cortex. The thinning is widespread, but severity varies by region.
Regions most vulnerable:
Parietal lobe (inferior and superior parietal cortices)
Frontal (Superior, middle and inferior frontal gyri)
Temporal cortex (superior and middle temporal gyri)
Thinning in temporal cortex is associated with future cognitive impairment
Temporo-parietal junction
Describe the relationship between brain structure and meditation that has been observed in the elderly.
Gray matter changes in specific brain areas, but not on global gray matter.
Meditators show less age-related gray matter atrophy in some brain areas (hippocampus/amygdala, posterior cingulate, orbital gyrus, anterior cingulate gyrus, mid cingulate gyrus)
Glucose metabolism (a marker of brain activity) is also preserved in meditators. Glucose metabolism normally declines with age, but the decline is less significant in meditators.
What are some mechanisms by which meditation may slow the effects of aging on the brain?
Stress regulation via reducing anxiety and depression
Improved sleep quality (imbalanced sleep causes cortical thinning)
Cardiovascular effects (BP and HRV)
Neuroplasticity (less cortical atrophy with age, increased thickness, effects on general memory, working memory, and metabolism)
Discuss research into the effects of meditation on telomeres, telomerases and cellular aging.
Telomeres: caps that protect the ends of chromosomes
▻ Telomeres ensure that genetic material is not lost during chromosome replication; when DNA is copied telomeres are truncated instead of DNA
Telomerase: the enzyme that maintains telomere length and prevents telomere shortening
Meditation may enhance telomerase but tends not to affect telomere length.
Discuss research into the effects of meditation on epigenetics with aging.
Epigenetics: changes in the expression or function of genes without changes in the genetic code.
As we age, there is increased methylation (an epigenetic process) in the DNA sequence.
Methylation is a marker of aging.
Methylation predicts aging as an epigenetic clock. In older meditators (>52 years) there’s a relationship between meditation and this epigenetic clock.
What is dementia? What is the most common form of dementia?
Dementia is a disorder marked by memory impairment, personality changes, and impaired reasoning.
Alzheimer’s disease (AD) is the most common form of dementia, affecting around 40 million people and around 10 to 15% of people over age 65.
Describe the features of Alzheimer’s disease.
Neurofibrillary tangles, acetylcholine transmission is reduced, progressive neuronal loss, b-amyloid plaques
What are some ways we can improve research into the effects of meditation on memory dysfunction in aging and neurodegenerative disease?
• Meditation may help slow the progression of AD, specifically via rescuing cognitive function loss during aging.
• Several risk factors for AD (hypertension, blood perfusion, and stress) are modulated by meditation.
• Disrupted mood and sleep are major difficulties in AD, and may be sensitive to meditation.
• It may also be worthwhile to examine the caregivers of AD patients.
