Brian Science: We have discussed previously the brain and how it ages. With this blog we are going a little more into the actual changes in the architecture of the aging brain. We know from previous blogs that as you get older, processing speed and reaction times in the brain slow down. Cerebral atrophy is the cause of decreased total volume and that is the reason your brain slows down.It is currently being debated whether it is cell loss or cell volume loss.
It is debated that loss in cell volume may contribute more than the loss cell number itself. Another factor in a aging brain is the decline in synapse number,and consequently the number synapses firing. This process can be accelerated by injury, infection or neurodegenerative disorders, and some studies have identified sex as a modifying factor.
In addition to reduction in brain volume, grey matter volume (mostly consisting of neuronal cell bodies) declines throughout adulthood and although white matter volume (myelinated axons) peaks during midlife, it also decreases thereafter. In addition the number and intensity of white matter lesions can be identified via MRI and are also common hallmarks of aging. Lesions are common as we grow older are caused by irregularities in small vessels of brain. as these lesions grow in size and number, they are heavily associated with several neurodegenerative disorders such as Alzheimer’s disease (AD), Dementia and Parkinson’s.
As people age, their bodily systems — including the brain — gradually decline. “Slips of the mind” are associated with getting older. That said, people often experience those same slight memory lapses in their 20s but do not give it a second thought.Older adults often become anxious about memory slips due to the link between impaired memory and Alzheimer’s disease. However, Alzheimer’s and other dementias are not a part of the normal aging process.
Common memory changes that are associated with normal aging include:
Difficulty learning something new: Committing new information to memory can take longer.
Multitasking: Slowed processing can make planning parallel tasks more difficult.
Recalling names and numbers: Strategic memory, which helps with remembering names and numbers, begins to decline at age 20.
Remembering appointments: Without cues to recall the information, the brain may put appointments into “storage” and not access them unless something jogs the person’s memory.
Although some studies show that one-third of older adults struggle with declarative memory — that is, memories of facts or events that the brain has stored and can retrieve — other studies indicate that one-fifth of 70-year-olds perform cognitive tests just as well as people aged 20.
Scientists are currently piecing together sections of the giant puzzle of brain research to determine how the brain subtly alters over time to cause these changes.
General changes that researchers think occur during brain aging include:
Brain mass: Shrinkage in the frontal lobe and hippocampus, which are areas involved in higher cognitive function and encoding new memories, starts at around the age of 60 or 70 years.
Cortical density: This refers to the thinning of the outer-ridged surface of the brain due to declining synaptic connections. Fewer connections may contribute to slower cognitive processing.
White matter: White matter consists of myelinated nerve fibers that are bundled into tracts and carry nerve signals between brain cells. Researchers think that myelin shrinks with age, and, as a result, processing is slower and cognitive function is reduced.
Neurotransmitter systems: Researchers suggest that the brain generates fewer chemical messengers with age, and it is this decrease in dopamine, acetylcholine, serotonin, and norepinephrine activity that may play a role in declining cognition and memory and increasing depression.
In understanding the neural basis of cognitive decline, researchers can uncover which therapies or strategies may help slow or prevent brain deterioration.
Brain Facts:
After the age of 40, the volume of the brain decreases and continues to decline at an accelerated rate after 70 years of age.
Although some studies show that one-third of older adults struggle with declarative memory — that is, memories of facts or events that the brain has stored and can retrieve — other studies indicate that one-fifth of 70-year-olds perform cognitive tests just as well as people aged 20.
Recent studies indicate that structural changes in the architecture of the brain can now be correlated so well with chronological age that predicting the age of a person can be done by looking at these brain changes of a person. So far scientists have been successful at predicting age of a person.with a absolute error of <5 years. This provides a potential use of neuroimaging to identify structural changes as a biological marker of aging and may be used to identify ‘accelerated’ or neurodegenerative variations.
about 40 % of Alzheimer's disease could be prevented or delayed through lifestyle changes, according to the Centers for Disease Control and Prevention.
Obesity in midlife may accelerate brain aging by around 10 years, and both sugar and diet varieties of soda are associated with poorer brain health.
So What: All of this leads us where? First, as we age our brian ages. Theres not a lot we can do about the fact that it's going to change. We can however, mitigate the effects of aging. Mitigation is a good word here because the facts of life are that we are going to change or rather our brains are going to change. We can however change the course of things and recent research helps in that respect. A growing body of evidence suggests that people who experience the least declines in cognition and memory all share certain habits:
engaging in regular physical activity
pursuing intellectually stimulating activities
staying socially active
managing stress
eating a healthful diet
sleeping well
I found it interesting that the September issue of Consumer Reports had a section on the brain and listed some points about lifestyle changes that can help with the issue of a aging brain. Below are some comments they mentioned.
They suggest,"What's good for the heart is good for the brain". that includes: not smoking, excessive alcohol use, getting exercise, treating mental health issues,develop a eating plan, keeping blood pressure and blood sugar in check..
Dancing!! they went off on dancing as an activity that requires cognitive challenges that are translated into rhythmic movement...great exercise for the brain. Interesting, Interesting.
( Note the picture used here looks just like someone who some of us know. it's not! But can you tell me who it looks like????)
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