Although these levels were studied in the normal human brain, the parietal and basal ganglia regions are often affected in degenerative brain diseases associated with aging and it has therefore been suggested that brain glutamate may be useful as a marker of brain diseases that are affected by aging. Neuropsychological changes
Changes in orientation
Orientation is defined as the awareness of self in relation to ones surroundings Often orientation is examined by distinguishing whether a person has a sense of time, place, and person. Deficits in orientation are one of the most common symptoms of brain disease, hence tests of orientation are included in almost all medical and neuropsychological evaluations. While research has primarily focused on levels of orientation among clinical populations, a small number of studies have examined whether there is a normal decline in orientation among healthy aging adults. Results have been somewhat inconclusive. Some studies suggest that orientation does not decline over the lifespan. For example, in one study 92% of normal elderly adults (65–84 years) presented with perfect or near perfect orientation. However some data suggest that mild changes in orientation may be a normal part of aging. For example, Sweet and colleagues concluded that "older persons with normal, healthy memory may have mild orientation difficulties. In contrast, younger people with normal memory have virtually no orientation problems" (p. 505). So although current research suggests that normal aging is not usually associated with significant declines in orientation, mild difficulties may be a part of normal aging and not necessarily a sign of pathology.
Nun Study
A study funded by the National Institute of Aging followed a group of 678 Roman Catholic sisters and recorded the effects of aging. The researchers used autobiographical essays collected as the nuns joined their Sisterhood. Findings suggest that early idea density, defined by number of ideas expressed and use of complex prepositions in these essays, was a significant predictor of lower risk for developing Alzheimers disease in old age. Lower idea density was found to be significantly associated with lower brain weight, higher brain atrophy, and more neurofibrillary tangles. Hypothalamus inflammation and GnRH
In a recent study (published May 1, 2013), it is suggested that the inflammation of the hypothalamus may be connected to our overall aging bodies. They focused on the activation of the protein complex NF-κB in mice test subjects, which showed increased activation as mice test subjects aged in the study. This activation not only affects aging, but affects a hormone known as GnRH, which has shown new anti-aging properties when injected into mice outside the hypothalamus, while causing the opposite effect when injected into the hypothalamus. Itll be some time before this can be applied to humans in a meaningful way, as more studies on this pathway are necessary to understand the mechanics of GnRHs anti-aging properties. Inflammation
A study found that myeloid cells are drivers of a maladaptive inflammation element of brain-ageing in mice and that this can be reversed or prevented via inhibition of their EP2 signalling. Aging disparities
For certain demographics, the effects of normal cognitive aging are especially pronounced.