- Our brains are machine-like
- Neurological health and use of redundant systems
- Praised be the brain’s plasticity
Depending on your belief regarding how the human species came to be you might take some degree of offense with the following statement – our brains are machine-like.
The fact that they still leave scientists and the occasional bioscience enthusiast both intrigued and frustrated by their complex and seemingly ever indecipherable design is just the cherry on top. And just like with a well-functioning mechanism, you know it’s doing a great job when you don’t notice it doing anything at all.
But this brilliant design, or, more precisely, the fact that scientists are still clueless about so many aspects when it comes to its inner workings is the main culprit in preventing individuals from detecting any signs of it beginning to deteriorate.
If the emerging wrinkles in the corners of your eyes, or the few patches of grey hair you have looked at with an existential stare have been enough to get your attention, imagine if you could somehow physically feel your brain degrading. Talk about a human experience we’re all missing out on.
Far from that scenario, however, the fact is that for the majority of adults even though they do indeed experience cognitive decline, it is hardly noticed. What should be understood by this is that they are able to lead their lives without another’s support and without being a danger to themselves or others.
Aging and Brain Function
If we were to look at the normal aging process up-close (like microscopically up-close) the two major pieces of information that would be presented to us would be that some sections of the brain have shrunk and that particular sets of neurons are no longer connected to others.
Speaking strictly from the standpoint of normal aging, this kind of degradation could easily translate into you forgetting to turn the lights off when leaving the house and having to remind yourself to do so with a sticky note on your door. This last bit makes all the difference. You coming up with a solution, and independently so, is a testimonial to the greatness of the human brain. More specifically, to its use of redundant systems. One might break down, but another takes its place immediately.
Is memory failing you? Good thing you’ve developed logical reasoning and future planning when you were younger. Sticking the sticky note on the door is not a sign of defeat, quite the opposite. Neurological health means your brain is able to maintain its capacity to adapt to newly encountered circumstances with the passing of time.
Aging and Brain Reconfiguration
Not nearly enough praise and attention are given to one of the most instrumental characteristics of the brain – its plasticity. Other organs keep performing the function/s they began performing when we were born should they not be affected by external damage or disease, but the brain is very much in a league of its own.
We start with billions of neurons as babies, none of which are useful until they are molded into something useful. This occurs for about 25 years on the average with the result being hundreds of thousands of established connections between neurons, each a testament to our learning experiences. Some of them the brain gets rid of should they serve no purpose, others are strengthened as our cognitive abilities are enriched by properties such as abstract reasoning, tempering impulsivity, assessing threats, etc. At some point, your brain will be fully formed, and immediately after it will start degrading. All brains in history have followed this pattern, and so does yours. No reason to cry at the sky.
Needless to point out the game-changing impact brought about by the progress made in regards to neuroimaging as far as the phenomenon of aging is concerned. This is how researchers were able to observe that if an older adult and a younger one have to perform the same task, their brain activity may look completely different from one another.
As one performs a thought-provoking activity, the engagement of the neurons all across their brain is required. To determine the actual brain power they are capable of the behavior of neurons that are far off from each other is of special importance.
The way distant neurons communicate with each other is through axons that spread in a tentacle-like manner from one neuron to another sending off an electrical signal. This entire wiring of axons is what scientists call white matter. The neurons themselves and other types of cellular forms within the brain are collectively referred to as grey matter.
Imagining tools such as the MRI (chronologically first) have revealed a weaker architectural integrity of the white matter in the brains of older adults, meaning that sending off electrical signals between distant neurons has become more challenging than in the brain of a younger person.
Essentially, older brains have to work harder, a phenomenon suitably named hyperactivation, and to this day, there isn’t sufficient data to determine whether it is to be considered a normal stage of aging or it should be thought of as pathological.
Additionally, what’s also being looked into concerning this matter is the brain’s ability to reconfigure itself and keep on performing various functions despite changes (degradation) in white matter. Is it a more nuanced redundant systems theory that could explain this? Or is it something entirely new? Either way, brains are on the job.