The Brain Controls Everything – Brain Structure and How Old Age Affects It
As we age, one organ we worry about is the brain. Will it keep functioning well so I can keep up? Will I start forgetting things and how bad will it get? Will I get dementia or, even worse, Alzheimer’s? Will I be able to keep up with all the new things coming along that seem to increase in numbers every year?
If your body keeps on ticking but you lose the capabilities of your mind, what good is it to be living? This is the number one fear of people as they approach later life. Who cares if I live longer if I don’t even know what’s happening?
Having a grandmother who survived a stroke but was left incapable of communicating, this is a very real fear for me. I want to not only be able to live longer than my parents and grandparents, I want to be mentally sharp and still learning while I do.
But before we get to the things we can do to help keep our minds sharp, let’s take a look at the brain, its structure, how aging affects it and the possible diseases of the brain.
The brain is by far the largest organ within the human body and without doubt the most complex, mysterious and intriguing all at the same time. It has been extensively researched and looked at for centuries, being both a source of fascination, along with conjecture, rumor and superstition. Even after all this time, we still know a fraction of its inner workings and functions.
The human brain is at the center of all we do in life. It is responsible for coordinating our body, regulating temperature, keeping us breathing, and responsible among other things for memory and understanding. It is also the real powerhouse, interpreting and acting upon internal and external influences throughout the central nervous system.
As humans we have not only one of the largest brains in nature, but also one of the most developed. As a result, our evolutionary path has led us to sacrifice an easy and quick growth from birth, in order to allow the brain to grow and develop.
Current research continues apace, but there are certain things we can say about the brain in confidence. These are best investigated by examining the actual structure and parts of the organ itself. As a whole the brain can be roughly divided into three areas, commonly known as the forebrain, midbrain and hindbrain. Each of these has separate structures in its structure, each interlinking out and performing separate and specific functions. In brief they are as follows:
This is also commonly referred to on the whole as the cerebrum. In fact the Cerebrum is merely part of the forebrain, along with the Thalamus and Hypothalamus.
The cerebrum is composed of a number of lobes found in this area. It is divided into 2 of what we call hemispheres, held together by the Corpus Callosum. The cerebrum is responsible for our actions and logical thought on the world around us. Each hemisphere has four lobes present, being the Frontal, Parietal, Occipital and Temporal which work to organize movement, speech, optical coordination and interpretation, emotions, logical problem solving, memory and hearing.
The thalamus is the socially mobile part of the forebrain. It has the most connections to the body and especially other parts of the brain. It controls motor function and function of the senses. Almost every nerve signal sending messages through its length passes through the Thalamus. It is a bit like a telephone exchange for the brain, relaying and intercepting signals before they pass on their way.
This little part of the brain does an awful lot by way of controlling and regulating internal conditions in our bodies in response to outside stimuli as well as less tangible responses to our needs. So it acts like a thermostat, controlling temperature within quite narrow margins, maintaining autonomic functions of the other organs and responding to and acting upon hunger, sleep, and sexual drive.
The hypothalamus has several important functions, including control of the body’s appetite, sleep patterns, sexual drive and response to anxiety.
The midbrain is mainly responsible for voluntary practical functions such as the senses of sight and sound along with coordinating muscles and organs responsible for them. So it helps deal with movement of the eyes and body that are deliberate rather than reactions.
It is made up of the Tectum, Tegmentum and Cerebral Peduncle. The later is vital for performing the movements that are voluntary and is made up of an enormous collection of sensory axons which stretches all the way through the brain stem and the cortex of the Cerebrum
The cerebellum, Pons and Medulla Oblongata make up the majority of the Hindbrain and are generally associated with fine control, automated internal systems and sensory coordination.
The Cerebellum looks like and is often called the ‘Little Brain’. In fact, it is the initial formation of the brain within any developing fetus. Like its big brother, it has two highly folded hemispheres and a cortex
Its main functions are motor function related. The Cerebellum converts any input from the ear and responds with the appropriate muscular output. It is the fine motor control and positioning that it provides following interpretation that we take for granted. A great example of that is the repositioning of your body when balancing
This filters and acts as a gatekeeper for auditory information received from the ear. That information passes through the Pons first of all. It works closely with the Cerebellum as a team with motor control and analysis of sensory inputs. It is thought that the Pons is also involved with sleep and consciousness levels.
This doesn’t really look like part of the brain. In fact, it has the appearance of an over developed portion of the spinal cord. But it has a vital function. The body’s almost automatic running of heartbeat rate, breathing and digestion is controlled efficiently and ceaselessly from here
As well as these main structures with their multitudinal functions, the brain also has other areas that provide a vital connection or part of its everyday running.
The Limbic System
The limbic system is a construction of neural pathways and routes, incorporating structures like the Hippocampus and the Amygdala. It crosses and connects to the white matter, brainstem and cerebral cortex.
In function the Limbic System controls, stores, interprets and produces emotional responses, expression of those emotions, appetite, food response and control over the storage and use of short term memory. It is affected easily by hormonal changes and disorders like stress and depression
The Brain Stem
This is really a grouping together of brain parts such as the Midbrain, Pons and Medulla oblongata. As a whole they control your life functions on a daily, hourly and millisecond basis.
So heartbeat, heart rate, blood circulation and pressure and breathing all fall into their area of responsibility
Neurons are the information highway of the brain carrying information in the form of electrical pulses throughout the brain. Many have specialized structures for specific functions. They are delicate and easily damaged, although contrary to what was previous thought, they may actually be able to undergo some repair or duplication after damage from trauma or other causes
The Brain in Old Age
The brain is still very much a mystery to science even with the wealth of discoveries already made. As the brain ages it was thought that the function of neurons gradually began to cease, which resulted in some disorders such as Alzheimer’s and other degenerative diseases affecting thinking and motor abilities.
This is now being debunked by scientists such as Caleb Finch, Ph.D., the ARCO/William F. Kieschnick Chair in the Neurobiology of Aging, who confirms that most of your neurons will remain healthy until you die unless injury has been suffered.
Technology such as higher resolution magnetic resonance imaging (MRI) and positron emission tomography (PET) scans are starting to help identify parts and areas that do fail with age to improve our knowledge.
There are some statements we can make though:
Memory loss due to age is more likely due to chemical changes in the brain
Alzheimer’s may be due to the presence of inflammatory proteins called amyloid aggregates, which are hard deposits formed by tissue degeneration. This is particularly noted in sufferers in the hippocampus section, which is for new memory formation (Attributable to Caleb Finch, PhD).
Genetics may be a major factor in many degenerative and even sudden events such as strokes which can lead to death or degeneration (Helena Chui, M.D., the Raymond and Betty McCarron Chair in Neurology).
Our lives influence our brains hugely. Continuing to exercise our intellect, head trauma from accidents from sports such as boxing, exercise, proper full sleep, hypertension and stress can all have positive or negative effects as we move into middle to old age.
Diseases and Disorders
There are at least 62 diseases and disorders either affecting or associated with the human brain (Source – The Brain Foundation). Of course not all of these are life threatening or serious. Many have minor effects on our daily life style that we cope with, such as migraines. Of course there are those which are more serious by their degenerative or potentially fatal nature, such as strokes or dementia (Alzheimer type or not).
The range of diseases and disorders are also broad in their effects and recovery chances. Concussion is an impact suffered by a direct blow. It can result in temporary memory loss, blurred vision and nausea, but can be recovered from in a short period of days with no real lasting effects. Whereas, an aneurysm is a severe rupture of an artery in the brain resulting in bleeding inside the brain, often resulting in death if severe and rapid enough.
The type of effect of these diseases is also two fold. They are broadly physical in nature with damage and resultant internal injury to the brain or in the behavior and cognitive ability or both being experienced.
Additional articles within this category will discuss different things we can do to help keep our minds sharp. The latest news about new discoveries concerning the brain will also be covered in our Anti Aging News blog.