Genetic Changes
Variation in the effects of aging among individuals can be attributed to both genetic and environmental factors. As in so many other science disciplines, the nature versus nurture debate is an ongoing conflict in the field of cognitive neuroscience. The search for genetic factors has always been an important aspect in trying to understand neuro-pathological processes. Research focused on discovering the genetic component in developing AD has also contributed greatly to the understanding the genetics behind normal or “non-pathological” aging.
The human brain shows a decline in function and a change in gene expression. This modulation in gene expression may be due to oxidative DNA damage at promoter regions in the genome. Genes that are down-regulated over the age of 40 include:
- GluR1 AMPA receptor subunit
- NMDA R2A receptor subunit (involved in learning)
- Subunits of the GABA-A receptor
- Genes involved in long-term potentiation e.g. calmodulin 1 and CAM kinase II alpha.
- Calcium signaling genes
- Synaptic plasticity genes
- Synaptic vesicle release and recycling genes
Genes that are upregulated include:
- Genes associated with stress response and DNA repair
- Antioxidant defence
Read more about this topic: Aging Brain
Famous quotes containing the word genetic:
“Man is not merely the sum of his masks. Behind the shifting face of personality is a hard nugget of self, a genetic gift.... The self is malleable but elastic, snapping back to its original shape like a rubber band. Mental illness is no myth, as some have claimed. It is a disturbance in our sense of possession of a stable inner self that survives its personae.”
—Camille Paglia (b. 1947)
“Nature, we are starting to realize, is every bit as important as nurture. Genetic influences, brain chemistry, and neurological development contribute strongly to who we are as children and what we become as adults. For example, tendencies to excessive worrying or timidity, leadership qualities, risk taking, obedience to authority, all appear to have a constitutional aspect.”
—Stanley Turecki (20th century)