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Posts Tagged ‘logic’

Right And Left Brain

February 17, 2012 1 comment

The brain is divided physically into a left and right half is not a new discovery. The Egyptians knew that the left side of the brain controlled and received sensations from the right side of the body and vice versa.

It is only in the last two dozen years, however, that the true implication of the left/right split has gradually become apparent, through the work of a number of researchers. The most famous are probably Dr.  Roger Sperry and Dr. Robert Ornstein of the California Institute of Technology. Their work has won them a Nobel prize.

Sperry and Ornstein noted that the left and the rig hemispheres are connected by an incredibly complex  network of up to 300 million nerve fibres called the Corpus callosum. They were also able to show that the two halves of the brain tend to have different functions.

They (and other researchers) indicate that the left brain primarily appears to deal with language and mathematical processes and logical thought, sequences, analysis and what we generally label academic  pursuits. The right brain principally deals with music, and visual impressions, pictures, spatial patterns, and colour recognition. They also ascribe to the right brain the ability to deal with certain kinds of conceptual   thought – intangible ‘ideas’ such as love, loyalty, beauty.

The specialization of the two halves of the brain can result in some bizarre behaviour. Patients who, for medical reasons, have had their Corpus callosum  severed,  have effectively two semi-independent brains: two minds in one head.

If a ball is shown to the left visual field of such a person, i.e. registered to their right brain hemisphere, the speaking half of the brain, which is in the other, (left) brain will claim to have seen nothing. If, however, the patient is asked to feel in a bag of assorted shapes he will correctly pull out a ball. If he is asked what he has done he will say ‘nothing’. The ball has only been seen with the right brain, and felt with the right brain. The speech centre, which is located in the left brain, has registered nothing.

Even more delicate experiments have been performed on surgically split-brained patients. The word SINBAD was projected to such a patient while his eyes were focused on the precise spot between N and B. The first 3 letters went to his right brain, the last three to his left hemisphere. When asked to saywhat he had seen, he replied BAD. When asked to point with his left hand to what he had seen he pointed to the word SIN.

The specialisation of the two brains  has also been demonstrated by measuring the electrical activity of the brain during various activities.

When the brain is relaxed in a state of rest, it tends predominantly to show an alpha brain wave rhythm – i.e. 8-12 Hz waves. Ornstein found that a subject tackling a mathematical problem showed an increase in alpha in the right hemisphere. This indicated that the right side was relaxing whilst the left was active and, therefore, in a beta brain wave pattern. In contrast, when a subject was matching coloured patterns, the left showed alpha (i.e. was resting) and the right showed beta (i.e. was active). More on brain waves can be found here.

The brain scans, show the varying levels of electrical brain activity in a subject listening to music, words and singing. The first activity (music) involved the right brain. The second (listening to words only) involved the  left brain, but singing (words and music together) involved the whole brain.

The left brain is now thought to be the half that specialises in serial, sequential thought, i.e. analysing  information in sequence in a ”logical” step by step approach. The left rationalises. The right brain seems to take in several bits of information ”at a glance” and process them into one overall thought. The right synthesises.

To read more click on this link to the full article: Right and Left Brain
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Brain Waves

February 10, 2012 3 comments

Introduction Brain waves

The brain generates tiny electrical pulses as The brain produces four main waves with thoughts traverse the labyrinth of the mind. The specific frequencies:

physical conduits of these thoughts are the millions of nerve cells or neurons in the brain. Just as radio signals, in order to make a comprehensible message, are beamed out on radio waves, a band of signals within a defined frequency, so the brain’s activity also occurs in waves. Brain waves can be measured on an electro-encephalograph machine (which is normally abbreviated to EEG Machine). By attaching sensitive electrodes to the scalp, it is possible to measure accurately the type of brain wave that a subject is producing. These waves are usually expressed in the number of cycles per second (CPS) or with their frequency (Hz).

1. Beta level brain waves – range 12-16 Hz (also 13-25 Hz)

2. Alpha level brain waves – range 8-12 Hz 3. Theta level brain waves – range 4-7 Hz
4. Delta level brain waves – range 0.5-3 Hz

The following chart relates each type of brain wave to its principal function. We must remember however, that when we speak of someone being ‘in alpha’ we mean that this is their characteristic and predominant brain wave. Other brain waves will also be present, but in smaller quantities than usual.

Brain activities

The linking of left and right brain activities is important in producing a shift from learning to accelerated learning. Yet our society is very ‘beta orientated’. We are busy thinking about the problem in hand, but don’t leave ourselves sufficiently open to other influences, which would help us memorize faster and make the sort of less expected connections that we call creative thinking.

Beta brain

In beta you don’t see the wood for concentrating on the trees. But learn to relax, increase the proportion of the alpha and ideally theta brain waves, and you have created the conditions where you may begin to see the whole picture.

Alpha brain

‘Alpha’ is a natural and receptive state of mind, that we can all attain through the techniques of relaxation. They principally involve simple and pleasant relaxation exercises and listening to certain types of music.

Theta brain

The theta brain wave pattern is especially interesting. It occurs spontaneously to most of us in the twilight state between being fully awake and falling asleep. Arthur Koestler called it ‘reverie’. This drowsy stage is associated with fleeting semi-hallucinatory images. Thousands of artistic and literary inspirations and scientific inventions have been credited to this state, a sort of freeform thinking that puts you in touch with your subconscious.

Brain waves interpretation

Many psychologists would agree it is a reasonable hypothesis that, when left/right brain symbiosis takes place, conscious and subconscious are also united. The proportion of theta brain waves becomes much higher than normal. This is the moment when logical left brain activity declines. The left brain, which normally acts as a filter or censor to the subconscious, drops its guard, and allows the more intuitive, emotional and creative depths of the right brain to become increasingly influential.

If the hypothesis is true, then do women, popularly characterised as more intuitive, reach a walking theta state more often than men; and can this be associated with the fact that their left/right brain link, the Corpus callosum, is larger and richer in connective capabilities than men’s? We do not yet know, but it is a fascinating area for future research.

At the University of Colorado Medical Centre and at the Biofeedback Centre in Denver, Dr. Thomas Budzyski has found that, when people were trained to achieve and maintain theta brain waves using biofeedback techniques, they did indeed learn much faster. Moreover, many emotional and attitudinal problems were solved at the same time.

To read more click on this link to the full article: Brain Waves (pdf).