Deep Brain Stimulation
Foundation dedicated to preventing and curing disorders of the brain, this group collected, organized, and disseminated information relating to the 1990s as the Decade of the Brain. The group maintained the Decade of the Brain coalition, which achieved by the end of the decade a large increase in federal funding for research on the brain. It also increased public awareness of the importance of brain research by producing educational TV programs, distributing reports and pamphlets, and operating traveling museum exhibits.
Our goal in creating the Methods & New Frontiers in Neuroscience series is to present the insights of experts on emerging experimental techniques and theoretical concepts that are, or will be, at the vanguard of neuroscience. Books in the series cover topics ranging from methods to investigate apoptosis, to modern techniques for neural ensemble recordings in behaving animals. The series also covers new and exciting multidisciplinary areas of brain research, such as computational neuroscience and neuroengineering, and describes breakthroughs in classical fields like behavioral neuroscience. We want these books to be the books every neuroscientist will use in order to get acquainted with new methodologies in brain research. These books can be given to graduate students and postdoctoral fellows when they are looking for guidance to start a new line of research. We hope that as the volumes become available, the effort put in by us, by the publisher, by the book editors, and by individual...
ERAN zAiDEL Department of Psychology, University of California at Los Angeles, Los Angeles, California. Marco iACOBONi Ahmanson Lovelace Brain Mapping Center, Neuropsychiatry Institute, Brain Research Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
The late 20th Century focus on cerebral laterality was due largely to the so-called split-brain patients. Academic studies followed by sensational stories in the popular press noted that very different functions of the two hemispheres can sometimes be measured in patients who had undergone severance of the corpus callosum (Sperry 1966, 1968 Sperry et al. 1969). The fact that all people contain two potentially independent brains in one skull became widely known, and attention was focused on precisely how those two brains -and possibly those two personalities - differ. While some of the speculation prompted by the split-brain research was excessive, the basic findings on the split-brain patients have stood the test of time such patients do show signs of internal contradictions as a direct consequence of the loss of cortico-cortical connections between the cerebral hemispheres (Gazzaniga 1995). It can therefore be inferred that the corpus callosum in the intact human brain acts to...
You may have heard the fact that you lose thousands of brain cells a day. For years, the scientific view of the adult brain was anything but encouraging. It was an unquestioned truth that your brain produced new brain cells only early in life and that upon reaching adulthood, your fixed complement of neurons would begin to dwindle. With this relentless cell death would come a sharp slide in your capacity to learn and think. We now know that this position was a combination of exaggeration and half-truth. Though it's true that most of your brain's neuronal growth occurs during childhood and adolescence, you continue to grow new neurons throughout your life a process known as neurogenesis. This capacity to produce new cells is a hallmark of the brain's plasticity, which allows it to continuously alter neural circuits and form new synaptic networks.
This finding has transformed the way neuroscientists think about the aging brain and memory. We now believe that, in most cases, no matter how old you are, your brain is capable of producing new brain cells that have the potential to support pathways that enable you to form new memories. And if the brain is able to generate new neurons, there's hope that one day it may be possible to offset the damage and severe memory loss brought on by degenerative brain disorders, such as Alzheimer's disease.
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The first scanner was developed as a brain research tool and was used clinically in 1973. Since then, CAT brain scans have improved the diagnosis and treatment of stroke, head injury, tumors, abscesses, and so forth and have superseded plain skull X rays and pneumoencephalography. magnetic resonance imaging (mri) has become the preferred technique for brain imaging, but CAT scans remain in use because they are cheaper and faster than MRi.
Chemical brain stimulation The study of brain function in lab animals by injecting various chemicals directly into the brain or ventricular spaces. The most common studies investigate drugs that stimulate or inhibit neurotransmitters, which are responsible for transfer of information from one nerve cell to another.
If ever there was a reason to turn off the sitcom reruns and read a book, it's this there's a connection between how much you use your brain and how well it performs as you age. Over time, people who challenge their minds maintain a greater degree of memory resiliency than people who are mentally disengaged.
These kinds of inferential difficulties are not unique to the brain imaging community. Current issues raised in interpreting brain imaging studies seem eerily similar to the debates over electrical brain stimulation in the 1950s. In a famous case, Jose Delgado claimed that he had identified the aggression centers of the brain (also, incidentally, in the caudate nucleus), and by remote-control stimulation of an implanted electrode could make a raging bull as passive as a gentle lamb. Delgado demonstrated his findings by placing himself in a ring with a Spanish bull and using his device to pacify the animal in mid-charge (Valenstein, 1973). The experiment worked the bull stopped - but not likely because he was truly pacified. Valenstein (1973) recounts that the electrodes were placed in motor-control regions of the caudate that forced the bull to turn in one direction (and probably confused the animal as well ).
I encouraged David to commit himself to a lifestyle that emphasized brain fitness. We discussed his risk factors for cerebrovascu-lar disease and what he needed to do in order to reduce them. These included maintaining a heart-healthy diet and adopting a vigilant stance with his blood pressure and cholesterol. To get 197
Do you tend to be a happy person If so, you can count your lucky genes, according to a recent study of identical and fraternal twins in which more than 50 percent of the variation in the set-point of human happiness was estimated to have a genetic basis.11 Do you tend to be anxious, alienated, and nonresilient to stress If so, you may curse your genetic fate, according to studies of monozygotic and dizygotic twins in which heritabilities greater than 50 percent were reported.12 Are you musically inclined If so, sing a song of praise to your genes that early in life may have influenced the developing suite of neuronal connections in your brain in ways that fostered the acquisition of musical skills.
Now stretch your brain around this concept in some cases, your phenotype might not be caused by genetics, but it might be caused by someone else's genotype rather than your own. In the case of Rh incompatability, when the baby has an Rh+ blood type and the mother has an Rh- blood type, the baby can develop anemia after birth as a result of exposure to maternal antibodies directed against the Rh+ proteins in the baby's blood. However, this can only happen after the mother has borne a previous baby with the Rh+ blood type. How many other factors that affect a baby's development before birth are also affected by the maternal genotype We can imagine that a variety of things, including hormone levels that affect whether the baby is delivered prematurely, and other factors affecting things such as nutrition and oxygenation could all affect the traits that will be observed in the new baby that do not depend on the new baby's genotype at all. So in this case the problem has underlying genetic...
It goes without saying that keeping up positive relationships with family and friends is emotionally and socially rewarding. But it's also good for your overall health and beneficial for your brain. The MacArthur study on aging and other research suggest that social support can improve mental performance.
Eran ZAIDEL Department of Psychology, University of California at Los Angeles, Los Angeles, California. Marco IACOBONI Ahmanson Lovelace Brain Mapping Center, Neuropsychiatric Institute, Brain Research Institute, David Geffen School of Medicine, University of California at Los Angeles, Los Angeles, California.
The next clue to the nature of consciousness is usually known as the binding problem and is perhaps the most problematic, because it relies on introspection. Look at a tree. How many leaves do you seen Tens, hundreds, thousands The problem for science is that the information encoding all those leaves - their colour, texture, position in space - is being processed in quite distinct regions of your brain. There is of course no problem in accounting for the functionality of such a system. So long as the multiple independent pathways in the brain come together at some point to provoke an appropriate response, this is a tree , then the system is functioning appropriately A computer that similar dissects the complex scene and processes that information - perhaps in a set of quite independent but parallel processors -would generate the same response. But a computer would not be provoked into writing, I think that I shall never see a poem as lovely as a tree. (Joyce Kilmer). To understand...
Magistretti et al. (39), using primary cultures of mouse cerebral cortical astrocytes, demonstrated the ability of Glu, the main excitatory neurotransmitter in the brain, to stimulate glycolysis, i.e., glucose consumption and lactate production. They hypothesized that Glu, released from active presynaptic neurons and taken up by astrocytes, is the signal that couples neuronal activity to glucose utilization. According to this hypothesis, astrocytic Glu uptake, via Na+ co-transport, activates the Na+ K+-ATPase pump. Glu uptake from the synaptic cleft occurs through specific astroglial Glu transporters, namely, Glu transporter 1 and astrocyte-specific Glu transporter (52). These transporters show a stoichiometry of 3Na+ contransported with each Glu molecule. The Na+-pumping activity, fueled with ATP formed by membrane-bound glycolytic enzymes, increases glycolytic flux and, thus, glucose consumption and lactate production. An additional ATP-requiring reaction takes place, upon Glu entry...
The job of the brain is straightforward to decide what the body should do next. Mostly in humans, and probably all the time for most animals, these decisions are made automatically by standard neural networks without influence of the CEMI field. However, occasionally the automatic pilot routines may come unstuck. You may be presented with a new or unfamiliar situation. It is at these times that your brain will be more likely to have lots of neurons whose membranes are poised close to the firing threshold the undecided brain. These undecided neurons will be sensitive to the (relatively weak) influence of the brain's electromagnetic field. Your conscious mind will be required to make a decision and the undecided neurons can plug into the vast quantity of information stored in the CEMI field. This proposed role for the CEMI field in brain activity in modulating neural activity is similar to what William James envisaged more than a century ago (as quoted in 40 ) if consciousness can load...
Two surgical procedures are available for the treatment of severe ET of the upper limbs and are equally helpful for parkinsonian tremor stereotactic thalamotomy and deep-brain stimulation (DBS) of the thalamus. Each procedure has advantages and disadvantages, and a full discussion is beyond the scope of this chapter, except to mention that thalamotomy should be avoided in the patient who requires a bilateral procedure because of the risk of dysarthria. Both procedures are highly effective for either curing or substantially reducing tremor contralateral to the operated side, and the risk of a serious complication is low. Unlike thalamotomy, DBS can be performed safely bilaterally. The physician should refer appropriate candidates to a center experienced in surgical treatment of tremor and, ideally, one where there is close collaboration between the neurosurgeon and a neurologist with expertise in movement disorders.
What's bad for your heart is also bad for your brain. Conditions that are risk factors for cerebrovascular disease and heart disease, such as high cholesterol, hypertension, and diabetes, increase the risk of memory problems. Controlling these disorders with medication, dietary changes, and exercise can help keep your memory in optimal condition.
Your brain and the brain of Leonardo da Vinci are the same, structurally, when viewing a face. While that statement may be true in the sense that the architecture and general schema of your brain are the same as Leonardo's, the specific functional characteristics are (likely) different. Without wiring your central nervous system to his, his view of life and your view of life can only be estimated. An individual's life experiences are stored in long-term memory cells. These cells provide an analytic
As you read this book, your brain is processing information, and if all goes well, you'll remember it for many years. But where, exactly, does this information go One of the most enduring myths about memories is that they're stored in one place in the brain a memory bank. Years ago, scientists assumed that you formed memories by depositing them in this bank and that you remembered things by withdrawing or borrowing them. Once you were finished using these memories, you returned them to the memory bank. Your Brain's Memory Networks What does all this have to do with memory It suggests that a single memory is not stored in a single place, like a book on a shelf. Instead, your brain breaks down a memory into its informational components and routes each type of information to the area of the brain that is specialized for processing it. Let's take an apple, for example. Your memory of an apple consists of how it looks, how it tastes, how it sounds when you bite into it, and so on. Each of...
Gemba, H., Miki, N., and Sasaki, K. (1995). Cortical field potentials preceding vocalization and influences of cere-bellar hemispherectomy upon them in monkeys. Brain Research, 69, 143-151. Jurgens, U. (1982). Amygdalar vocalization pathways in the squirrel monkey. Brain Research, 241, 189-196. Jurgens, U., and Zwirner, P. (2000). Individual hemispheric asymmetry in vocal fold control of the squirrel monkey. Behavioural Brain Research, 109, 213-217. Kirzinger, A., and Jurgens, U. (1982). Cortical lesion effects and vocalization in the squirrel monkey. Brain Research, 233, 299-315. Kirzinger, A., and Jurgens, U. (1991). Vocalization-correlated single-unit activity in the brain stem of the squirrel monkey. Experimental Brain Research, 84, 545-560. Muller-Preuss, P., and Jurgens, U. (1976). Projections from the ''cingular'' vocalization area in the squirrel monkey. Brain Research, 103, 29-43.
Brain Information Service A cooperative effort of the UCLA Brain Research Institute and the Biomedical Library that provides rapid, accurate, and complete information in the basic brain sciences to aid investigators and teachers. Subject areas of the service includes alcohol and sleep research it does not cover the literature of diagnosis and treatment of neurological diseases.
Though the disease is chronic and has no cure, there are medications that can relieve the movement symptoms by providing dopamine. The motor response to medication does not necessarily predict the cognitive response. Surgery and brain stimulation techniques have been developed for treatment of some patients for whom medication does not adequately control the movement disorder.
For years, scientists regarded fat in the diet as universally bad for your brain. But we now know that only some fats are bad for your memory, whereas others are actually beneficial. Your brain can suffer under the influence of saturated fats (found mainly in meat and dairy products) and trans fats (found mostly in processed foods with partially hydrogenated oils). But your brain can thrive on It stands to reason that saturated fat is bad for your memory and unsaturated fats are beneficial. Saturated fat contributes to heart disease, hypertension, and high cholesterol, each of which increases the risk of age-related memory loss. Unsaturated fats are known to protect against these cardiovascular disorders. And we know that what's good for your heart is also good for your brain.
In any simulation using a bilateral (two hemisphere) architecture, the issue of the unity or duality of mind must be addressed. The topic of dual consciousness has already been thoroughly debated within the framework of the so-called split-brain research (e.g., Puccetti 1981 Schiffer 1998) and the preponderance of behavioral evidence seems to favor the view that, in the split-brain condition, the hemispheres can exhibit two rather independent modes of thought (Gazzaniga 1995 Sperry 1966). In the normal state with an intact corpus callosum, however, behavioral duality is rare or absent, suggesting that in-terhemispheric neural connections somehow force a mental unity on two nerve centers that, at least potentially, could diverge. This unity is a consequence of two factors
Proteanism does not imply that all of your brain cells are firing randomly in total cortical anarchy. The randomness is injected into your behavior at a particular level appropriate to the situation. If you are fleeing randomly, your trajectory through the environment may be unpredictable. But you are still maintaining order at many other levels coordinated nerve firings to activate muscles, coordinated muscle movements to power limbs, coordinated limb movements to maintain an efficient gait, and eye-foot coordination to avoid obstacles. Proteanism implies the strategic ability to use randomness just when it is needed to make yourself unpredictable. It does not imply a masochistic enslavement to Fortuna, the pagan goddess of chance. Here proteanism foreshadows human creativity, since creativity implies the strategic use of novelty to achieve a social effect, not the random combination of random ideas in a chaotic style.
One site promises amazing instant results for a photographic memory, allowing you to memorize volumes of information in minutes. Another offers memory tools linked to the godhead and other divine sources. One of my all-time favorites is a program that awards the participant Olympic-style medals for various cognitive areas and includes a game of learning bird sounds as a tool for mind expansion and building brain power. I must admit that the product pitch that began with Lapses of memory can kill caught my attention.
Have you ever been envious of people who seem to have no end of clever ideas, who are able to think quickly in any situation, or who seem to have flawless memories? Could it be that they're just born smarter or quicker than the rest of us? Or are there some secrets that they might know that we don't?