Deep Brain Stimulation
A number of surgical interventions are viable options to give further symptomatic relief and minimize any drug-induced complications. This is intended to protect or restore dopamin-ergic transmission by repairing dysfunctional basal ganglia circuits. Different neurosurgical approaches have been extensively discussed elsewhere by other investigators (57,58). Basically there are three general types. The traditional method is to make an ablative lesion to disrupt part of the circuit. However, this method is irreversible postoperatively. The second method is deep brain stimulation (DBS) where an electrode is implanted in the central part of the brain to electronically modulate the circuit. This method has received more attention because it is reversible and adjustable postoperatively (59). Ablative lesion and DBS have been performed at different parts of the thalamus, pallidum, and subthalamus to compensate for the biochemical effect of DA deficiency. The third method is brain restorative...
In Sweden, the Swedish Brain Power program started in 2005 based on funding from the Invest in Sweden Agency (ISA) and five other foundations. The overall aim is to improve early diagnosis, treatment, and care for people with neurodegenerative diseases. The Svenska Demensregistret (the Swedish Dementia Register), is one useful by-product of this initiative. Established in 2007, its aim is to build a national quality register with data on, among other things, improved diagnostics, treatment, and follow-up for patients with dementia disorders. This will create new possibilities to improve the quality of Swedish dementia care. Some 15 clinics and one health center have already begun to report their data to the register.
Brain stimulation via application of pulsed electrical current to the left cervical vagus nerve has established efficacy as adjunctive therapy in treatment-resistant epilepsy and also has been studied in treatment-resistant depression. The procedure requires surgical implantation of a device that applies small doses (typically less than 1.5 mA) of electrical current to the vagus nerve multiple times per second (a typical frequency is 20 Hz) for varying periods, with a typical schedule being 30 seconds every 5 minutes. The dose is externally controllable and is typically set to cycle continuously, 24 hours per day. Side effects are usually minimal and include voice alteration, neck pain, and dyspnea. Psychotropic medications are commonly administered concomitantly, and even ECT has been administered to patients with an implanted stimulator, although the device was turned off during ECT (Marangell et al. 2002).
Your brain releases antidiuretic hormone. These two responses result in increased intake of fluids and decreased excretion of urine, which together cause an increase in the amount of water in the body and a return to the normal level in the concentration of dissolved solids.
Blood pressure varies throughout the day. When you sleep, blood pressure falls your tissues need less oxygen and nutrients. When you exercise, the opposite happens. Your muscles need more oxygen and energy to perform work, and your blood pressure rises, increasing blood flow to the tissues that need it most. Even standing up affects blood pressure To get more blood up to your brain, blood pressure rises.
Nonetheless, the notion of bidirectional changes in synaptic excitability achieved in the LTP LTD paradigms of amygdala and hippocampal slices and, preliminarily, in the kindling quenching phenomena, led us to explore the potential frequency-dependence of rTMS in attempts to find optimal therapeutic parameters of this type of brain stimulation in man. Following initial observations of our group, in collaboration with Wassermann and Hallett of the National Institute of Neurological Disorders and Stroke (NINDS), that 20-Hz stimulation of the left frontal cortex of depressed patients appeared able to induce antidepressant effects in some subjects (154), we, and others, conducted more controlled studies demonstrating weak to substantial antidepressant effects of higher-frequency (10- to 20-Hz) stimulation (over the left but not right frontal cortex or occiput) in severely depressed patients (155,156). Whereas Pascual-Leone et al. (156) reported rather dramatic effects on mood with this...
This procedure of oxygen enrichment should not be done without proper instruction. Parents are taught the oxygen enrichment program only after they attend the What to do about your brain-injured child (WTD) course and their child has been evaluated at The Institutes. Alternatively, parents can attend the WTD course and the information can be given to the child's primary doctor, to start the oxygen enrichment program. Oxygen enrichment is not appropriate for some children with cardiac defects. It should not be used in children with respiratory diseases in which carbon dioxide is abnormally retained, such as uncontrolled asthma or obstructive pulmonary disease. Rebreathing should never be done when there is pneumonia, fever, vomiting, or severe upper respiratory infections.
It had been paradigmatic that, at least in ECT, a seizure was the necessary prerequisite for therapeutic effects (163,164). Although this may be the case for ECT, the emerging data suggest that this is not the case for rTMS. We have postulated that whereas seizures are necessary for the induction of the adaptive changes in ECT that are the therapeutic principles in depression, rTMS may be able to evoke some of these adaptive mechanisms more directly without the requirement of a seizure (157). Thus, it is well known that ECT in man (165,166) and electroconvulsive seizures (ECS) in animals (167,168) increases TRH mRNA and TRH protein, which has been postulated to at least partially relate to ECT's therapeutic effects (164,169). Perhaps alterations in TRH mRNA or the other critical neuroadaptive changes pertinent to the effects of ECT could eventually be induced by appropriate nonconvulsive brain stimulation parameters with rTMS. To the extent that this becomes possible, it would...
Given the discussion of compensatory mechanisms in the previous section, one could wonder about the differential effects of different frequencies of brain stimulation achieved with rTMS over different locations on neurotrophic factor gene expression as well. The presence of BDNF is required for the induction of some types of learning and memory, as revealed through knockout strategies in mice (186) that is, in hippocampal slices prepared from BDNF-deficient mice, LTP cannot be induced. Moreover, these mice show impaired spatial learning in a Morris water maze (186). Could appropriate rTMS stimulation increase low levels of BDNF or other neurotrophic factors that have been decreased by stressors or preprogrammed at a low or high level based on genetic vulnerability We predict that these questions will be answered in the not too distant future and that rTMS and other non-convulsive brain stimulation paradigms will begin to be utilized for therapeutic purposes. These may be particularly...
Schultz based his development of AT on two sources his own experiences with clinical hypnosis and Oskar Vogt's observations on brain research. Schultz noticed that hypnotized patients usually reported two specific sensations a strange heaviness in the limbs and a similarly strange sensation of warmth. He believed hypnosis was not something the hypnotist did to patients, but instead was an experience patients allowed to happen to them. Schultz believed in a point of change, a kind of switch when the patient would enter into the hypnotic trance. He wanted to find a way to allow the patient to control this switch.
Every second, millions of signals make their way to your brain and inform it about what your body is doing and feeling. Your nervous system interprets these messages and decides how to respond. Responding to stimuli requires the actions of specialized cells called neurons. Neurons are capable of carrying electrical and chemical messages back and forth between your brain and other parts of the body. These electrochemical message-carrying cells are often bundled together, producing structures called nerves. Neurons and nerves are extensively networked throughout your body. They are found in your brain, spinal cord, and sense organs such as your eyes and ears. Nerves connect various organs to each other and link the nervous system with other organ systems (Figure 13.1). As sensory information is passed to and from your brain, it travels through the main nerve pathway the spinal cord. Your spine, which protects your spinal cord from injury, is made up of 33 separate bones called...
The cerebellum controls balance, muscle movement, and coordination (cerebellum means little brain in Latin). Since this brain region ensures that muscles contract and relax smoothly, damage to the cerebellum can result in rigidity and in severe cases, jerky motions. The cerebellum looks like a smaller version of the cerebrum (see Figure 13.6). It is tucked beneath the cerebral hemispheres and also has two hemispheres connected to each other by a thick band of nerves. Additional nerves connect the cerebellum to the rest of your brain (Figure 13.8).
Neurons transmit impulses from one part of the body to another. Many kinds of stimuli, including touch, sound, light, taste, temperature, and smell, cause neurons to fire in response. When you touch something, signals from touch sensors travel along sensory nerves from your skin, through your spinal cord, and into your brain. Your brain then sends out messages through your spinal cord to the motor nerves, telling your muscles how to respond. To evoke this response, nerve cells must transmit signals along their length and from one cell to the next.
Arjen van Ooyen is a researcher at the Netherlands Institute for Brain Research. He has a PhD in theoretical neurobiology from the University of Amsterdam. His principal research concerns modeling neural development neurite outgrowth, axon guidance, and axonal competition. Further information can be found on his website at www.anc.ed.ac.uk arjen. Jaap van Pelt received his PhD in Physics in 1978 at the Free University in Amsterdam. His research group, Neurons and Networks , at the Netherlands Institute for Brain Research (NIBR) investigates, both experimentally and by theoretical and computational approaches, neuronal morphology and activity-dependent mechanisms in neurite outgrowth and neuronal network formation. Further information can be found on his website at www.nih.knaw.nl jaapvanpelt.
Novel techniques such as multiple subpial transections, vagal nerve stimulation, deep brain stimulation, direct cortical stimulation, chronic drug infusion, and gene therapy are currently being investigated as further palliative therapy for patients who are not suitable for resective surgery of their epileptic focus.
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?