Problem 7
LG:
- How does aging affect cognitive abilities and how do they change over time?
- How can we alter (improve) cognitive abilities? Factors?
- How does training affect cognitive abilities of older people?
- How does aging influence our brain development?
Drag – contemporary review 2009: cognitive aging
Biological changes:
- Normal aging is accompanied by physiological changes in the brain both structurally
and functionally
- Structurally:
o brain declines in volume (not uniformly across regions)
o frontal cortex is most affected, declining faster
o white matter declines are greatest in anterior regions and myelinated fibers
are more susceptible to breakdown in this region
o decline in gray matter is greatest at frontal regions
o hippocampal atrophy, also associated with memory loss
o hippocampal volume loss is associated with decreased memory performance
o brain volume changes are minimal in younger and middle-aged adults
o rate of age-related volume decline accelerates with age
- Cerebrovascular system:
o decreases in resting blood flow, metabolic rate of oxygen consumption and
vascular reactivity of cerebral vessels
o changes in functional blood flow
o hemispheric asymmetry reduction in older adults (HAROLD) model shows that
prefrontal activation during cognitive processes is less lateralized in older
adults
- Theory of functional compensation
o These patterns of activation reflect the recruitment of alternate brain regions
to counteract neurocognitive decline
o Aging brain needs to engage in additional areas to generate the same amount
of resources as younger adults
- Scaffolding theory by Park and Reuter-Lorenz:
o Increases in functional brain activity (especially frontal cortex) represent
‘compensatory scaffolding’
o Scaffolding: recruitment of additional circuitry that reinforce declining
structures whose functions are noisy and inefficient
o Scaffolding is not a response to aging but challenge and even younger adult
brains do it
- Functional activation patterns tend to be less specific in older age
- Declines in neural integrity lead to reduced specialization or differentiation of task-
specific behaviors
LG:
- How does aging affect cognitive abilities and how do they change over time?
- How can we alter (improve) cognitive abilities? Factors?
- How does training affect cognitive abilities of older people?
- How does aging influence our brain development?
Drag – contemporary review 2009: cognitive aging
Biological changes:
- Normal aging is accompanied by physiological changes in the brain both structurally
and functionally
- Structurally:
o brain declines in volume (not uniformly across regions)
o frontal cortex is most affected, declining faster
o white matter declines are greatest in anterior regions and myelinated fibers
are more susceptible to breakdown in this region
o decline in gray matter is greatest at frontal regions
o hippocampal atrophy, also associated with memory loss
o hippocampal volume loss is associated with decreased memory performance
o brain volume changes are minimal in younger and middle-aged adults
o rate of age-related volume decline accelerates with age
- Cerebrovascular system:
o decreases in resting blood flow, metabolic rate of oxygen consumption and
vascular reactivity of cerebral vessels
o changes in functional blood flow
o hemispheric asymmetry reduction in older adults (HAROLD) model shows that
prefrontal activation during cognitive processes is less lateralized in older
adults
- Theory of functional compensation
o These patterns of activation reflect the recruitment of alternate brain regions
to counteract neurocognitive decline
o Aging brain needs to engage in additional areas to generate the same amount
of resources as younger adults
- Scaffolding theory by Park and Reuter-Lorenz:
o Increases in functional brain activity (especially frontal cortex) represent
‘compensatory scaffolding’
o Scaffolding: recruitment of additional circuitry that reinforce declining
structures whose functions are noisy and inefficient
o Scaffolding is not a response to aging but challenge and even younger adult
brains do it
- Functional activation patterns tend to be less specific in older age
- Declines in neural integrity lead to reduced specialization or differentiation of task-
specific behaviors
