The Science Behind The Synaptitude Program
For healthy individuals, age-related cognitive decline can begin long before retirement. In addition, dementia is likely the result of a long-term process extending over 20 to 30 years. In Alzheimer’s disease (AD), the hallmark ß-amyloid plaques start to accumulate in the brain long before clinical symptoms become evident. These plaques are often distributed along the default mode network, an important system of functionally connected cortical regions that is active during wakeful rest and involved in self-referential thought and autobiographical memory.
Early intervention is best and most effective when implemented before the onset of cognitive decline. Diet, exercise and cognitive training interventions have been shown to significantly decrease the risk of cognitive decline in at-risk older adults and improve overall cognitive test scores, executive functioning and processing speed post-intervention. Consequently, the Synaptitude program combines (1) preventative strategies to reduce risk factors for cognitive decline by optimizing sleep, diet and physical activity and (2) plasticity-based strategies to improve cognitive function through brain training.
Why Sleep Matters
Sleep plays an important role in memory consolidation and restorative processes in the brain. Neurotoxic proteins, such as ß-amyloid, are cleared from the brain via the ‘glymphatic’ system, a network of vascular pathways that facilitate the removal of waste products. Clearance of ß-amyloid has been shown to occur twice as rapidly during sleep as during wakefulness. Furthermore, better sleep consolidation has been shown to reduce the deleterious effects of a common AD genetic risk factor (APOE Ɛ4 allele) on the risk of incident AD, the rate of cognitive decline and the density of neurofibrillary tangles in older adults.
Why Diet Matters
The Mediterranean diet is generally characterized by high consumption of vegetables, legumes, fruits, cereals and monounsaturated fatty acids (MUFAs, mainly olive oil); low consumption of meat, poultry and saturated fatty acids; and moderate consumption of fish, dairy and wine. High intake of MUFAs has been linked to reduced risk of age-related cognitive decline, fish and cereal intake to lowered AD prevalence and moderate red wine intake to decreased dementia risk. Higher adherence to the Mediterranean diet was associated with a 17-28% reduced risk of mild cognitive impairment (MCI) and a 45-48% reduced risk of MCI conversion to AD.
Why Physical Activity Matters
Boosting levels of moderate-intensity aerobic activity has been shown to improve AD cognitive assessment scores and delayed memory recall in older adults with self-reported memory problems. Older adults who participated in a 1-year aerobic exercise training program also saw an increase in hippocampal volume and significant improvements in spatial memory. Improvements in cardiovascular fitness have also been linked to greater task-related hemodynamic activity in cortical regions involved in attentional control and reduced activity in regions sensitive to response conflict. Resistance training has likewise been effective in improving cognitive function. After 6 months of progressive resistance training, older adults saw improvements in global cognitive function and a corresponding increase in the gray matter of the posterior cingulate cortex, a key hub in the default mode network. In a separate study, older women who participated in a 12-month progressive resistance training program showed significant improvement in tests of attention and conflict resolution while participants in twice-weekly sessions demonstrated greater hemodynamic activity in cortical areas associated with inhibitory control and slower progression of white matter lesions than those who participated in once-weekly sessions only.
Why Brain Training Matters
Older adults, who were trained on memory, reasoning or processing speed tasks as part of the longitudinal Advanced Cognitive Training in Vital Elderly (ACTIVE) study, showed cognitive improvements immediately after the training period and up to 2 years post-training. Targeted cognitive abilities also declined at a slower rate for trained participants up to 5 years after the initial training period. After 10 years, the risk for dementia was reduced by up to 48% for the processing speed training group. In older adults with MCI, computerized cognitive training was effective in slowing the decline in overall memory performance. Although the effects of cognitive training are often restricted to the targeted cognitive domain, auditory-based cognitive training has been shown to improve speech perception as well as memory and processing speed in older adults.
Effect of Sleep on Brain Health (Video)
40% of Canadians suffer from sleep disorders, putting them at risk for multiple health problems such as depression and dementia. View the video below to learn more.
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