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BRAIN COMPUTER INTERFACE FOR TREATMENT OF NEUROLOGICAL DISORDERS Introduction to Neurological Disorders Treatment of ADHD Using BCI Ethical Complications Future Developments Treatment of ALS Using BCI Importance of BCI & Sustainability Neurological disorders affect the nervous system, which is composed of the brain, spinal cord, and nerves. Neurological disorders typically cause trouble speaking, swallowing, breathing, or focusing. However, cognitive ability remain unaffected. Two neurological disorders we will be focusing on are ALS and ADHD. ALS is a neurological disorder caused by degeneration of neurons in the brain. As they degenerate, they lose the ability to fire and send neurons to the muscles which cause muscles to atrophy or weaken as shown in Figure 1. Although at first symptoms seem minor, in later stages the disorder makes it impossible for a patient to live independently. ALS Figure 1 ADHD ADHD is a disorder most likely due to chemical imbalances in the brain that affects attention and hyperactivity. It affects about nine percent of school-age children. ALS (Amyotrophic Lateral Sclerosis), or Lou Gehrig’s disease, is a crippling disease for those plagued by it. By the later stages, those affected by it can become completely paralyzed and unable to communicate or even breathe and eat. However, using BCI technology, communication is still a possibility, even for those in the later stages of the disorder, because their brain still functions as it should. Communication becomes possible by monitoring the P300 brain waves, which are emitted based on the person’s reaction to a stimulus. The patient will have electrodes attached to their scalp in various places that will be connected to an electroencephalogram (EEG). This machine monitors brain activity by monitoring brain waves emitted while the person thinks or acts. The EEG will monitor the brain waves that are emitted while the person is interacting with the BCI to determine intent and display words and letters that the person wants to say. An image of this process is show in Figure 3. There are two different types of BCI that can be used to portray messages; the first is a dependent BCI, and the second is an independent BCI. Figure 3 Figure 4 Figure 5 ADHD is the most common disorder that affects children and their academic performance. ADHD generally results in worse overall grades, more failing marks, higher likelihood of dropping out. To increase focus and attentiveness in ADHD patients, the brain must be taught how to focus intently for extended periods of time. BCI technology can provide repeated therapy sessions that train the brain how to do this. BCI treatment for ADHD currently consists of repeated therapy sessions, where the patient plays a video game that only runs while the brain waves coming from the patients indicate that he or she is paying attention. This indication comes from an analysis of the brain waves and the stimuli coming from the game. The assumption is that the game will be stimulating enough to keep the child’s attention, so that the child focuses on the game more. As the child’s focus increases, and the continuous amount of time played increases, the game gets more interesting and complex. This time of prolonged focus will help to train the brain to focus on something for extended periods of time. Figure 4 shows a picture of the BCI gaming therapy session for an ADHD patient. The treatment consisted of eight-week training containing 24 therapy sessions, followed by 3 monthly booster-training sessions. Figure 5 shows the results of this therapy and how the overall average inattentiveness, and hyperactivity decreased. Human Nature and Technology Therapeutic Ethics As BCI use and development continues, several other ethical complications arise. Many people worry that with the considerable promise of nanobiotechnology and neurosciences there is the potential of transforming the very nature of human beings. Pushing the boundary between humans and machines can potentially alter what it means to be human and human nature itself. Human nature can be defined as a set of physical characteristics that are biologically determined. The issue is whether BCI technology is ethical considering it can expand human cognition to improve health and physical capabilities but has the potential to add new features to the human experiences that are beyond biological characteristics and beyond human embodiment. In order to address this philosophical and ethical issue, it is best to assemble BCI use into three levels of application. Level 1: Therapeutic Use The purpose is to restore neurological functions prior to the development of the disease or neurological damage. Therapeutic application focuses on enhancing certain traits or abilities to a reference. Recipients are patients whose mental capacities are weakened (ALS and ADHD patients, as well as those in need of neuroprosthetics). Level 2: Enhancement The purpose is to exceed normal capacities and to improve biological abilities. Recipients of BCI are less likely patients with neurological troubles and more likely individuals wanting to improve their mental capacities for non-health related purposes. Level 3: Alteration This is most controversial because the main goal is to exceed biological boundaries. Although means to do so are unknown so far, several people fear this altering. Recipients could be those implanting memory or additional capacities into a person through a brain chip. If we limit BCI use to therapeutic use, many of these concerns about this technology will be eradicated. By defining BCI application for therapeutic use, one can address whether it falls into this category. BCI use raises concerns of harm and risk even at the therapeutic level. Even in therapy, the recipient must permit BCI use. The doctor or administrator must obtain informed consent, and when this is impossible due to complete paralysis, the legal guardian can give his or her consent. After a patient has given informed consent, many concerns toward BCI use are lessened. It has tremendous therapeutic application that could help thousands of people with various neurological disorders. Issues Facing BCI Technology Low practicality because they take a long time to be used Importable which makes them difficult to use in regular daily life. Low accuracy due to high signal noise ratio (SNR), when background noise interferes Uncomfortable for patients in regular use because of being hooked up to electrodes and BCI New Developments A new technology that is in development is a wireless, implanted sensor that would increase signal strength and decrease outside noise to receiver. By implanting the small sensor into the cranium and brain, it greatly reduces the effective outside noise that alters the accuracy. Also, the use of this sensor will allow more freedom for those using it, as they will no longer have to be tethered to a BCI with a large power cord and other wires. This makes this technology much more practical, as people do not have to sit in one place during their use. BCI technology has the ability to restore impairments of neurological disorders, helping the people these disorders affect and the people who take care of them. These devices can restore the ability to communicate for those with ALS, ultimately repairing the disconnect between the person and the outside world and allowing them to communicate with their friends and family. BCI can also restore attentiveness and activity in those with ADHD by retraining the brain to focus for extended period of time without losing attentiveness. Brain computer interface can sustain the quality of life by making human existences more enjoyable and less burdensome. By: Brian Jordahl and Jennifer Klein Dependent BCIIndependent BCI Relies upon neural pathways.Does not depend on neural pathways. Depends upon intense visual concentration. Input is based on what the person’s intent is. Uses a virtual keyboard with a matrix of letters that flashes one at a time. Uses visual keyboard and VEP as well. BCI picks up Visual Evoked Potential (VEP), which is the electric potential difference as a result of seeing that flash of light either on the key that person is focusing on or not. VEP is greater on the key that the person is focusing on. Relies on the P300 brain wave—only matters that the person is thinking about the computer key when it flashes. It can take up to 30 seconds just to produce once character of a word. More effective, long-term treatment option as they can be used in the latest stages of ALS. Brain Computer Interface Brain computer Interface (BCI) serves as a system that allows a person to control a computer or other electronic device using only his or her brainwaves. The brains electrical activity is detected through the scalp, from the surface of the brain, or from within the brain, and is then processed by a device to extract patterns indicating the user’s intent. Electrodes are placed on the surface of the scalp, which are connected to an EEG to detect patterns. These patterns can then be translated into commands like moving a cursor on a computer screen of communication. Figure 2 demonstrates how a BCI takes brain waves and converts it into command. The brain waves act as an input that is converted to a digitized signal that the BCI can interpret. The signal is then processed by an algorithm and converted to an output. Figure 2 Signal to Noise Ratio Signal to noise ratio (SNR) is a measure of the signal strength against the background noise. If there is a large amount of background noise in relation to the signal strength coming from the BCI, there is a large possibility for useless information that can negatively alter the accuracy of the technology.
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