NERVOUS SYSTEM – Brain and its disorders
Man is the most intelligent of all animals. The human brain seems to have more IQ (intelligent quotient) than any other living creature. All animals use their brain only for continued existence, i.e., to get food, to escape from danger, to get protected, etc. But human beings think rationally and invent new things for leading life more comfortably. Human brain seems to be a mystery and seems to be extraordinarily complex.
Brain is very much essential for our living, survival and communication comfort with environments. It is the main switch of the wired network of our body. With electrical impulses, they communicate, interact, interpret, coordinate and function efficiently, in a very fast manner in a fraction of a second through the cranial nerves (12 pairs) and spinal nerves (31 pairs). Billions and billions of nerve cells are engaged in the maintenance work of our body under the supervision of the brain. This super computer (brain) has uniqueness of mind and memory also. They can conduct messages at the rate more than 20 km per minute. This speed makes its functions invaluable.
All our body’s virtual functions are carried out, controlled, correlated and regulated by the brain. Due to its importance, nature has placed it in a high position and in a safe vault (skull). Really, one needs to bow one’s head before Nature’s mystery.
weighing less than 1.5 kg, is the boss of the body. It weighs approximately 2 per cent of the total body weight. This is the highest proportion among all living creatures comparing
brain and body weight. The richness of connection accounts for human intellect and talent. IQ and ability of brain varies from person to person and also from male to female. Here experiences and interest of the person also count. At a young age, it is highly adaptable and good in learning things easily. For moulding it perfectly to lead a good future, education in early life is thus very important.
Brain consists of an inner white and outer grey matter. Human brain has many folds with bulges and grooves for having more extended surface for recording. But, of course, all the theories say that human beings do not use more than 50 per cent of their brain’s capacity. The bulges are called gyri and grooves are called sulci. Brain has rich blood supply from carotid and vertebral arteries. In addition, it has been nourished through cerebrospinal fluid which circulates from ventricles of the brain to the entire spinal column.
Brain can be divided into three divisions:
- Fore brain – consists of cerebrum, thalamus, hypothalamus and glands (pineal and pituitary)
- Mid brain – Reticular formation, i.e., connecting area of forebrain and brain stem
- Hind brain – consists of cerebellum and brain stem (medulla oblongata and pons)
Fore brain and its functions Cerebrum – covers 80 per cent of the brain’s weight and volume. Cerebrum has two symmetrical hemispheres separated by a deep fissure. Even though they can mimic attributes, their functions seem to be entirely different. Each area has specific responsibility and function. Two hemispheres are interrelated with connecting fibres called corpus callosum.
Crossing over of nervefibres occurs in brain stem, so that the right side of the body is controlled by the left cerebral hemisphere and the left side of the body is controlled by the right side brain (cerebral hemisphere). The reason for crossing over is less understood. For human beings, commonly (for right handed persons – most common), the left hemisphere of the brain seems to be dominant and has the speech area (Broca’s area). Due to the left hemisphere’s dominance, every day- to-day activities will be taken care of with the right hand and leg in a more powerful manner than the left.
Cerebrum is an authority for development of personality, behaviour, intelligence, memory, emotions, etc. It also controls the voluntary muscles engaged in speech, breathing and swallowing. Cerebrum is covered by cerebral cortex and meninges (insulation layer). Cerebral cortex is the registry for memories, plans, ambition, etc. Unless otherwise this area is kept perfect, one cannot remember anything even about himself. In gist,
- Left cerebral hemisphere is responsible for thoughts, speech, words, etc.
- Right cerebral hemisphere is responsible for cognitive processing, rational thinking, fine skills, creativity, etc.
Further, cerebrum can be divided into four lobes and named after their covering bones
- Frontal lobe – responsible for planning, rational thinking and memories
- Parietal lobe – responsible for vision and understanding
- Temporal lobe – responsible for auditory
- Occipital lobe – responsible for vision
Thalamus – it is the base of the fore brain and the roof of the mid brain. It works more with sensory organs, i.e., eyes, ears, nose, tongue, fingers, etc.
Hypothalamus – controls emotions, body temperature, thirst, sleep, appetite, pulse, etc.
Pituitary and pineal glands with thalamus and hypothalamus work for growth and controlling body hormones for maintaining good body functions.
Mid brain and its functions – It is a very small connecting area of fore brain and brain stem. It is called as reticular formation. It controls and coordinates all the actions of brain. It filters impulses and gives importance and value according to urgency and interest, for example – one who sleeps in
the midst of TV sound wakes up for a calling bell. Here all the TV sounds have been filtered by this reticular formation and calling bell has been given importance and allowed to wake up the brain.
Hind brain and its functions
Cerebellum is a Latin word which means little brain (cerebellum itself resembles brain). It is placed in the back end of the head (occipital region) and it is also divided into two hemispheres like the cerebrum. It is the authority for coordination and balancing during movement and while changing body posture, for example during drawing, playing, running, etc.
Brain stem consists of medulla oblongata and pons. It is the collection of nerve fibres that ascend from the body and descends from the brain. It coordinates all the body impulses and brain’s messages. It also controls automatic functions, like breathing, heart beat / rate, blood pressure, swallowing, digestion, blinking, etc.
There are innumerous complaints that can arise from brain – starting from simple tiredness to coma, i.e., dizziness, drowsiness, sleeplessness, sleepiness, lack of concentration, loss of memory, headache, migraine, fits / seizure / epilepsy, paresis, paralysis, cerebrovascular disorders ( stroke ), brain tumours, meningitis, encephalitis, Parkinson’s disease, Alzheimer’s disease, brain atrophy, etc.
Prevention of brain problems – brain cannot be replaced, so prevention is most important. Also prevention is simple, i.e. need to care for head against any injury or disease. If any disease is not treated properly, it can end life ultimately by spreading to / attacking brain. For example – coma arises due to uncontrolled diabetes , hypertension, liver disorders, kidney disorders, heart disorders, etc.
- Physical as well as mental exercises (reading, thinking, solving puzzles / problems)
- Wear helmet while riding bike or working in mines or industry to avoid head injury
- Keep diabetes, hypertension and cholesterol level under control
- Proceed to treatment as early as possible in all complaints
- Narcotics, sedatives, smoking, alcohol and unnecessary drugs
- Unnecessary anxiety, fear, tension and worries
Diagnostic techniques – Brain functions and diseases are usually analysed with weakness, coordination of movement(s), reflexes, spasticity, alteration in sensations and functions, etc., to plan for treatment. The common tests required to detect brain disorders are
- Routine blood tests and urine tests
- X-ray skull (in AP view and lateral view)
- CT / MRI scan
- Electroencephalography (EEG)
- Analysing cerebrospinal fluid with spinal puncture
Dr. S. Chidambaranathan, BHMS, MD (Homeo)
24 E. New Mahalipatti Road
Tel: +91-452-233-8833 | +91-984-319-1011 (Mob)
(Disclaimer - The contents of this column are for informational purpose only. The content is not intended to be a substitute for professional healthcare advice, diagnosis, or treatment. Always seek the advice of healthcare professional for any health problem or medical condition.)