reading engagement 3

what features of the brain did scientists study?

cortical thickness, brain area, regional volume

what were some of the neurological disorders that were looked at?

dementia, multiple sclerosis, schizophrenia, MDD, MCI, bipolar disorder

general results

diseased brains appear older than healthy ones, revealing a gap between their predicted and chronological ages

diseased brains are further along the human aging trajectory

how large is the difference in brain age gaps between people with dementia and healthy controls? MCI and healthy controls?

4 years; 2 years

what disorders had the largest brain age gap (biologically, the brain aged fastest)? the smallest?

MCI, multiple sclerosis, dementia, schizophrenia

mixed psychoses, bipolar disorder

what part of the brain aged fastest in schizophrenia? MDD? dementia and multiple sclerosis?

frontal lobe; temporal lobe; cerebellar-subcortical region (some subcortical regions have been linked to memory loss and dementia)

how does the BAG relate to functional scores?

the size of a person’s BAG correlated with their functional scores, specific to each disease

in dementia, larger brain age gaps were associated with lower scores on the Mini-Mental State Exam

in multiple sclerosis, bigger gaps were associated with lower scores on the Expanded Disability Status Scale

how do genetics play a role?

genetic variation may explain some of the age gap - many brain disorders are heavily influenced by genetics

SNP data

common SNPs explained 24% of the variance in BAGs in healthy controls

161 SNPs were associated with both the BAG and a neurological disorder

of the 161, 6 were specific for dementia, and 5 of the 6 were in introns (including SATB2)

SATB2

encodes a DNA binding protein that mediates attachment of DNA to the nuclear matrix

many neurodegenerative disorders (including AD) have been associated with the disruption of the nuclear lamina

importance

provides a first step toward understanding the relationship between genetics, brain development, and brain disease

other imaging tests may reveal other patterns of brain aging in disease

the BAG may show up before symptoms of a given disorder