4 Flashcards
Resistance and aerobic training (ideally combo of both) helps with slowing down cognitive decline
Some argue that age cognitive decline starts in 20’s some say 60’s
This is due to the different forms of studies used
Longitudinal studies, cognitive decline starts much later in life in later adulthood
Can brain training limit age-related cognitive decline?
Although research findings are not consistent, a number of large scale studies suggest that brain training may combat age-related cognitive decline
example of brain training
Project ACTIVE (Advanced Cognitive Training for Independent and Vital Elderly)
Benchmark(gold star,best) for cognitive training research
Project ACTIVE
2802 participants, aged 65 or older (selected because of more inclined to demonstrate cognitive decline)
Received multiple 60-75 minute training and practice trials in memory training, reasoning training, or speed training
Outcome measures included activities indicative of functional independence:
1)instrumental activities of daily living (IADL ie paying bills, taking meds)
2)everyday problem solving (making change, searching medication label for side effects)
3)everyday speed (finding items on a simulated grocery shelf, reactions time in response to traffic signals)
ACTIVE Conceptual model
1) randomly assigned participants to 1 of 3 possible interventions:
1)memory training
Ie recalling walking along a path and remembering the memories
2)reasoning training
Ie Reasoning through the patterns
2)speed training
Visual identification of objects on a screen, became harder as the time to identify the object decreased
2) 3 proximal outcomes (outcome of domain related tasks) of active model
1)memory
2)reasoning
3)attentional processing speed
3) primary outcomes:
Everyday problem solving
IADL (instrumental activities of daily life), ADL function
Everyday speed
4)Secondary outcomes
Health related quality of life
Mobility
Health service utilization (ie: needing support in nursing home)
ACTIVE study design
Participants were given a booster training immediate post test
Memory booster, reason booster, and speed booster
Then assessed at 2 years and given the same booster training
Assessed again at 3, 5, and 10 years
Outcome of ACTIVE study
At 10 years researcher found that
a)proximal outcomes: reasoning training and speed training were associated with enhanced performance on domain specific tests (reasoning, speed of processing)
~Impacts of memory training were not as evident
b)primary outcome: all 3 trainings: memory, reasoning, and speed training were associated with enhanced performance on instrumental activities of daily living
d) secondary outcomes: memory training, reasoning training, and speed training were associated with enhanced health-related quality of life
e)secondary outcomes: reasoning training and speed training were associated with enhanced mobility
What is cognitive reserve?
the capacity to optimize and maximize cognitive performance in the face of increased task demands and/or neurological impairment to the brain (ie: age related structural and functional changes to the brain)
CR incorporate 2 subcomponents:
The ability to utilize standard brain networks relatively efficiently when completing cognitive tasks
The ability to recruit alternate, “nonstandard” brain networks when completing cognitive tasks; referred to as “compensation”
Measuring CR
Formal education
IQ
Linguistic skills/literacy (good grammar)
Occupational achievement
Participant in cognitively stimulating leisure
activities
Social engagement
Socioeconomic status
A multi-domain index of CR (index of Cognitive Reserve)
What are neurological correlates of cognitive reserve?
A substantial body of research has documented cognitive reserve among older adults in the form of compensation in response to age-related structural and functional changes to the brain
examples of compensation in response to age-related structural and functioning in the brain
1)hemispheric asymmetry reduction in older adults
2)posterior-anterior shift in aging
1)Hemispheric asymmetry reduction in older adults:
In contrast to younger adults, older adults have a higher tendency to use both hemisphere of the brain (increased activation of prefrontal cortex in BOTH hemispheres of the brain)
2)Posterior anterior shift in aging:
Less activity in exterior regions and more activity in frontal regions
Older adults exhibit lower levels of brain activity in posterior regions of brain (occipital lobe) and higher levels of activity in anterior regions of the brain (frontal lobe)
example:
Young adults working on verbal working memory rely heavily on left hemisphere of brain, when same task is done in older adults, both hemispheres are used
Park and Reuter-Lorenz proposed the scaffolding theory of aging and cognition (STAC)
According to this model, the aging brain adapts to neurological changes by building alternate neurological circuitry
The scaffolding process does not begin in older adulthood, it occur over lifespan when brain is confronted with cognitive challenges
Among older adults, cognitive function reflects the magnitude of structural and functional deterioration to the brain coupled with effectiveness of compensatory scaffolds
STAC
aging
neural challenges
functional deteriroation
compensatory scaffolding
scaffolding enhancement
Neural challenges
Evidence of shrinkage to brain as we get older: most notable frontal lobes, hippocampus (memory), cerebellum(balance and gait)
Changes to white matter deterioration: myelin sheaths deteriorate as we age
Damage to myelin sheaths at the front of the brain when we’re younger and as we age the damage shifts to back of brain
Reduction in synthesis and transporters,receptors of dopamine-> dopamine decline
Functional deterioration:
Dedifferentiation of ventral visual area
Medial temporal recruitment:
Increased default activity
Dedifferentiation of ventral visual area
reduced specificity of specific neural regions
As we get older brain areas that are specialized become less specialized
Medial temporal recruitment
as we get older we exhibit functional impairment in medial temporal lobe
Increased default activity:
brain activity that occurs when we’re at rest increases
Brain shows more default activity when we’re at rest when were engaged in cognitive activity as we’re older
Greater difficulty suppressing activity when at rest
Compensatory scaffolding:
Frontal recruitment:
Neurogenesis
Distributed processing:
Bilaterality
Frontal recruitment:
as we get older more scaffolds created in anterior areas of the brain
Neurogenesis
ongoing neurogenesis(new neurons are formed in brain) in hippocampus and olfactory bulb
Bilaterality
hemispheric asymmetry reduction in older age
We tend to rely less on one hemisphere or the other but increase of scaffolds on both hemispheres to complete tasks
Distributed processing:
brain’s ability to recruit additional or alternative neural resources to maintain cognitive function as it ages
Scaffolding enhancement
we can actively engage in pursuits that increases scaffolding
New learning
Engagement
Exercise (aerobic and resistance training)
Cognitive training
