Behind the Scenes of The Brain Show
Page 6
A brain wiring network that is activated frequently becomes more resistant and more difficult to abolish. If it encodes a certain behavior pattern we wish to avoid, the de-learning process becomes more difficult, since the neural, structural framework already exists and confiscates some energy resources from the energy reserve of our brain. It is more difficult to cancel and dismantle an existing structural neural framework, or to weaken the links between groups of neurons, than to lay a new structural framework that will serve as a bed for sprouting of a new pattern of behavior. It is easier to teach an old dog a new trick than to annihilate an old one.
Acquiring mastery of a behavioral or thinking skill is done in at least two stages. First, there is an expansion of the neural networking dimensions that constitutes the brain map that encodes the newly learned skill. The more we practice the skill and get better at it, fewer and fewer neurons are necessary for its performance, and the performance becomes more efficient in terms of accuracy and duration. Faster performance derives from faster transfer of signals through the network that encodes the skill. As we become more proficient, the task is performed more accurately as a result of neural networking that encodes the substantial aspects of the task and contains less and less “white noise.”
When neural networks that serve as infrastructure for behavior patterns clash with each other, it might lead to a situation known as “cognitive dissonance.” A conscious preference of one behavior pattern over another, for a long period of time, might lead to de-learning of the non-preferred behavior pattern.
A possible “childish metaphor” for such a situation is the building of two Lego blocks models, which are based on the same building blocks. Preference of one model over the other involves the dismantling of the other (if it is already built) and using the dismantled building blocks for the creation of the new model. Our brain resources are limited with respect to the neural infrastructure (despite the huge arsenal of nearly a hundred billion neurons) and with respect to the available energy resources. Therefore, new learning often involves cancelation of older learning and recycling of the old infrastructure for the sake of building a new infrastructure of neurons networking.
It seems that we are able to upgrade the performance of tasks that are important to us by initiating “conscious cartography” in order to unstitch the fabric of neuron columns of the maps that encode the skills that are no longer needed. On the other hand, we should initiate weaving of cortical columns for new brain maps. A process of upgrading existing maps is also plausible by adding resolution to a certain skill by means of weaving additional layers and attaching them to the map that maps the specific function.
Brain Electricity
The Glowing Path—Electric Memories
Thought that brings its owner to enlightenment about a certain revelation is often described by comic book artists as a light bulb above the person’s head. Indeed, at any given moment the electric activity in the brain can light up a 25-watt bulb. It is not yet considered an alternative energy source for our world, however. This bioelectric current is at the basis of our ability to preserve memories and create thoughts, and through its course from one neuron to another we can observe the glowing path of memory and thought.
Electrical activity of the brain takes place 24/7. In deep sleep, the activity is characterized by slow, low-frequency waves, which distinguish it from the fast outbursts that characterize the reaction of the neurons to stimulation while we are awake. Some compare the slow activity during sleep to the screen saver in our computers. Our brain cells are active around the clock, and even when experience impressions are not thrown on them intensively, they still retain a basic continuous level of activity.
Electroencephalography (EEG)—Tracing Brain Waves
Standard EEG is a graphic recording of electrical activity in the brain. Such a recording can be compared to eavesdropping to brain sounds through the skull walls; it records shallow activity of the brain rather than activity of deep structures at its core. Electricity is produced in the brain by means of activation of voltage-gated ion channels at neuron membranes.
The graphic manifestation of the electric activity in brain cells is wavy patterns that are called “brain waves.” The popular measure for their characterization is frequency. The conventional measurement unit is the number of waves per second, which is measured in Hertz units. A popular classification of the electric activity in the brain, as it is measured on the skin of the scalp in an EEG test, is according to five main frequency ranges:
Gamma Waves Pattern—These describe brain activity waves at a frequency of 35 Hz and above (thirty-five waves and above per second). This pattern characterizes intensive brain activity.
Beta Pattern—These describe brain activity waves at a frequency of 12 Hz and above (twelve waves and above per second). It characterizes a wakefulness status in most brain areas during everyday activity (standard working status).
Alpha Waves—Their frequency is 8–12 Hz (eight to twelve waves per second), and they characterize sleepy wakefulness and relaxation.
Theta Waves—These are waves at a frequency of 4–8 Hz (four to eight waves per second), typical of light sleep or deep meditation.
Delta Waves—These waves are typical of deep sleep. They are characterized by the lowest frequency: 0-¬4 Hz (up to four waves per second).
While recording brain activity at a given moment, it is common to find electric activities at different frequencies at different brain areas that appear simultaneously.
High-frequency brain waves (beta and gamma) are in correlation with fast, intense brain activity, with maximum concentration and higher levels of the neural mediators serotonin and dopamine, which contribute to serenity along with cognitive vigor. “Rapid thinking”—the status in which our brain produces thinking products at a fast pace—is known to be related to high spirits. (And, here, we face the question of the chicken and the egg, in other words—does the rapid thinking pace improve our mood, or is it the elevated mood that leads to rapid thinking pace?). On the other hand, low frequency brain activity is in correlation with a low level of serotonin and dopamine and is related to low mood and cognitive fatigue.
The EEG graph of a fully conscious, awake person reflects chaos within expected borders. It is difficult to foresee the exact activity-spurts patterns, but they exist within specific borders.
There is correlation between the modes of consciousness and the manifestation of brain waves: the alpha waves are expressed in a status of relaxation when we are awake and our eyes are closed. The theta waves are expressed when our attention beam scatters. The working assumption of most neurofeedback therapists is that the activity of the slow waves, especially the theta frequency, is in correlation with the scattering of attention and mental focus, while rapid-waves activity and, in particular, beta frequency, is in correlation with the focus of attention. When the main melody of our brain is played in an alpha rhythm, we are in a state of relaxed wakefulness.
Among children who suffer from attention deficit disorder (ADD), EEG tests often reveal an intensified activity of low-frequency brain waves (theta) and medium-frequency waves (alpha) in the frontal lobes and, on the other hand, scarcity of high-frequency beta waves.
Among other tasks, the EEG, like a seismograph, searches the brain for an “electric earthquake” of an epileptic seizure. Epileptic automatism, such as repetitive, involuntary movements, is the result of irregular electric discharges that sometimes interrupt with consciousness—our reality interface.
The Bull Experiment—Conditioning and Evaporation of Impulsiveness
In 1965 researcher Jose Delgado carried out experiments in which he inserted electric pacemakers into the brain of bulls. By means of the currents that were inducted into their brain by a remote control, the bulls were conditioned to attack and end the attacks abruptly, in accordance with the signals that were sent to them by the researcher. The bulls turned into a kind of marionettes activated by invisible threads that were
actually radio waves that inducted electrical currents in their brain.[6] These studies later led to using chips and pacemakers in the brain in cases of diseases related to disorder of brain function.
The Distance Between Laughter and Crying–a Few Millimeters
Inserting a pacemaker that inducts electric current in specific brain areas is known as a treatment to relieve symptoms of advanced Parkinson’s disease. An experiment in which electrical pace making was performed in an area at the brain core—the subthalamic nucleus (STN)—among Parkinson patients in an advanced stage of the disease revealed that electric stimulation in areas in proximity to the STN by a few millimeters leads to a response of automatic laughter or, alternately, automatic crying. In other words, behavioral expressions that reflect opposite emotions (laughter and crying) were produced from electrical stimulation of brain areas that are only a few millimeters apart from each other.
Mystic Experiences and the Temporal Lobe
A study conducted by a group of researchers from the University Medical School in Geneva[7] in which electrical stimulation of the temporal lobes among healthy participants was performed showed that the stimulation led to induction of “out-of-body-experiences,” such as a sense of separation from the physical body. Such experiences are sometimes reported by people who were on the verge of death due to physical illness. In addition, the electrical stimulation caused induction of visions of mystical content.
An Analog Brain in a Digital Era
The brain uses analog signal processing, which means the information processing in it is successive, unlike modern computers that digitally process exact but separated, non-continuous signals. The brain stores the information in a holographic pattern—i.e., in neural networks that exist in the three space dimensions. In addition, brain processing is also time-dependent (manifested as its ‘chrono-architecture’), which adds another dimension to the three space dimensions.
The Meridians of the Mental Chi
As energy channels in ancient Chinese medicine, so neural paths in the brain channel the transmission of information necessary for various cognitive processes.
The neuron columns are the main scaffoldings in the building of thinking. The information flows up and down the columns. Brain processing is based on the neurons and the information dance that flows through them and between them.
The perception of phenomena in the outer world, within a uniform domain of time and space as a major component, derives from the perception of ourselves as the reference point. Inner body information impressions, originated in signals sent from our body, are mutually connected to outer impressions. The whole experience is a combination of inner and outer information impressions that are confronted with existing insights and forecasts related to them.
Daydreams
Constantly Active
Our brain never rests, and its energy consumption does not change significantly, whether it deals with a strenuous task or ponders leisurely.
The never-ending activity of our brain, which is like “a city that never sleeps,” was reflected in the words of Hans Berger (the inventor of the EEG, which graphically describes the brain’s electrical activity). In 1929 Berger said that, according to his findings, it is obligatory to deduce that intensive activity takes place in the brain not only during wakefulness.
In the past, the prevailing assumption was that when we are in deep thought, resting in our rocking chair, our brain is also at rest. However, contemporary studies show that even when we are at a vacation state of mind, our brain cells are full-time workers, and our brain is as active as a beehive. Various measurements, based primarily on quantifying the amount of oxygen and glucose consumption and blood streaming to various brain areas, from which we deduce the level of activity in different brain areas, showed that the “activity gap” between dreamy rest and intense activity is estimated to be less than 5 percent, and it can be said that the level of activity is quite similar in both conditions. Even when our thoughts carry a wandering stick, our brain is as active as when they are focused on an exciting computer game.
The brain is a tough employer; the neurons are employed 24/7. Brain cycles do not rest, and they are active throughout the day, seven days a week.
A main component of general brain activity, which is estimated at 60–80 percent of the entire activity, takes place in the brain cycles, which are unrelated to outer events. This invisible activity constitutes most of the activity in the brain, and the amounts of energy channeled into it are in proportion to it.
The Oasis of the Imagination
When reality is boring at the emotional level (a state of mind reflected in the expression, coined by author Salvoj Zizek, “Welcome to the desert of the real”), our brain craves a sip of escapism that will carry it away from the desert of its realness toward the oasis of the imagination. The “infomania” (tirelessly longing for new information) is also a type of escapism that puts our brain resources in the hands of the ever-changing world manifestations. The need for escapism causes many of us to wallow in the universe of news, which is created and destroyed momentarily—and this is the secret of newspapers and the news flashes on TV, radio, or Internet.
The frequent shifting of glances toward routine nuisances, which flash in our mental field of vision now and again, often prevents us from gazing inquiringly at the core manifestations of reality. The compulsive occupation with everyday nuisances, which consume our time and energy in an attempt to float in the whirlpools of the sea of life, prevents us from focusing on the fundamental issues. It seems that our tendency to focus on the essential issues is higher when we rest under the coconut trees in the oasis of our imagination.
The neural infrastructure that equips our thoughts with a walking stick and sends them to the lands of imagination is called “the neural network of the default system.”
The Neural Network of the Default System
At times of rest and relaxation, the brain activates a neural activity pattern that is called “the default network.” This network is active whenever the reality manifestations do not knock on the doors of our brain vehemently. This network is like the eternal flame; it is always active, and the height of its flames is in inverse correlation with the level of challenge in which the outer world forces our brain to deal. The more we are focused on an exterior task, the less active the default network is. When dealing with more demanding tasks that require more brain resources, the network’s level of activity is low, since resources are needed elsewhere for a more urgent need. The correlation is fixed and nearly linear. The more difficult the task is, the less active the network is, and, on the other hand, whenever the brain deals with an easy task, the network’s activity raises its stature.
The default network is mostly active when our attention beam is not focused on the outer world manifestations but, rather, when it is focused inward. The consequence is the inside vision (introspection). In addition, moreover, the default network is active whenever our brain is sailing in the river of life in a dreamy, reflective mood. The transition from directing our attention beam inward to directing it outward is formed in a continuous, persistent pattern, and our attention pendulum moves between the ends according to the circumstances.
The windows of our consciousness are similar to the windows in our life; sometimes the light that comes through the windows washes over our room, and sometimes we look from the inside at the view outside these windows.
The default system’s level of activity lessens at once when there is a need to focus our attention beam on something else. It increases instantaneously when the need to focus our attention lessens.
When we “talk business,” and are busy with a target-oriented activity, our attention focuses on the interface with the world manifestations, and introspection is abandoned. It might lead us to feel that we “lose ourselves” in the midst of the events with which we deal. Circumstances sometimes force us to be present in the “here and now” rather than in the promising zones of the future
, which can be misleading.
A person whose default network is in a state of intense activity might look as if he is in a world of his own. In the provinces of default thinking, the only companion of a man is usually the man himself. The brain is as chatty as always, even when its owner is silent.
Assumptions Regarding the Role of the Neural Network System of Default
One common assumption is that the default system is involved in memory processing and in preparation of the brain for future scenarios. According to this assumption, the default system is a sort of a garden bed that enables the flowers of focused attention to grow in it, instantly, at the time of need, when a sudden stimulation requires a rapid response. In addition, the system is also believed to be a sort of super synchronizer that allocates frequencies and prioritizes activities and, by doing so, enables the various brain areas to talk to each other on their typical frequency ranges, preventing a chaotic situation in which one frequency is mixed with another.
A study carried out on mice that were navigating through a maze showed that the shooting pattern of bioelectrical potentials in their brain at times of rest was a sort of backward reading of the sequence of potentials while the mice were learning to navigate through the maze on their way to the cheese. This is the basis for the common assumption, according to which a rest period is also a “different type” of a learning period. The brain assimilates the information and expands its processing even when we are resting after the learning period. This might be the source of the expression “to sleep on it” as a manner of assimilating information.