Abstract — There are a number of people in the world who suffer from disabilities which prevent them from being able to use traditional means to control a computer. For these people, alternate forms of input are required. One potential input device is an Electroencephalography machine which can be used to detect patterns of brain activity and use these patterns to trigger events on a computer such as mouse clicks or keyboard presses. This allows those without the use of their hands to be able to control a computer without invasive surgery.
I. INTRODUCTION
Electroencephalography or EEG is a technique which uses electrodes to detect and amplify the electrical potential which corresponds to the firing of neurons in the brain. Although each neuron produces its own signal when it fires, it is nearly impossible to detect the activity of a single neuron via EEG. Instead, the firing of thousands of neurons in a pattern produce a signal which is strong enough to be picked up via electrodes placed on the scalp. These patterns can be used to analyse and diagnose mental conditions such as epilepsy, to monitor and observe brain responses to external stimuli, or as a potential means of hands-free control over a system.
Fig. 1 One Second of EEG Signal [2]
Clinical Electroencephalograph devices use a particular electrode placement known as ‘The International 10-20 System for Placing Electrodes’, or simply the 10-20 system. This method was developed in order to standardize the placement of electrodes on the scalp so that studies could be reproduced easily. The name comes from the fact that the distance between electrodes is either 10% or 20% away from each other. The layout of the 10-20 system is shown in Figure 1.
Fig. 2 The 10...
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[2] Wikipedia. (n.d.) Electroencephalography. Retrieved May 11, 2009, from Wikipedia: http://en.wikipedia.org/wiki/Electroencephalography
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[5] WisBusiness, “UW-Madison: Researchers use brain interface to post to Twitter”, http://www.wisbusiness.com/index.Iml?Article=156008
Other testing procedures that are commonly employed, in order to gain a better visual image of the excitatory activity in the brain are the PET scan and the MRI. According to Kalat (2004), these methods are non-invasive, meaning that they don’t require the insertion of objects into the brain, yet they yield results that allow researchers to record brain activity. The PET scan (positron emission tomography) involves the researcher injecting a radioactive chemical into the patient’s body, which is then absorbed mainly by the brain’s most active cells. With the use of radioactive detectors, placed around the patient’s head, a map is produced that shows which areas of the brain are most active.
The purpose of this paper is to inform the reader about Wilder Penfield and his research over electric brain stimulation. This essay will give a brief biography of Wilder Penfield, a description of his research, and finally discuss the insight his experiments provided and the influence they had on our body and behavior in general.
The skin technologies that have recently been created are astonishing. The remarkable breakthrough has made a huge advance in technology happen. Muscle and nerve control operation is when electrodes are permanently implanted into the nerves and muscles allowing the amputees limb to have total direct control. With this new muscle to nerve action
Enns, M. W. M., Reiss, J. P. M. M., & Chan, P. M. (2010). Electroconvulsive therapy. Canadian Journal of Psychiatry, 55(6). (Enns, Reiss & Chan, 2010)
Technology and the Brain As a college student, using the internet and technology is a daily task. Everything you need for your classes: schedules, homework, quizzes, and even tests are all online. The debate on technology and the brain suggests that technology may have an effect on the brain, effect multi-tasking, and cause addiction. Brain Activity
In normal sleeping patterns a person usually passes through five phases of sleep, the fifth being REM. The sleeping human passes cyclically through these five phases throughout a night's rest. These phases can be defined in electrical activity of the brain; much like the activity of the heart is often defined. The technique of measuring the electrical activity of the brain is call Electro-encephalogram, or EEG. When the electrical events of a person's brain are graphed on a electrical magnitude versus time axis the graph of a person who is in different stages of being asleep or awake appear to have different levels of electrical activity occurring in the brain. (See (14))
The diagnosis of epilepsy is usually made after the patient experiences a second unprovoked seizure (Leppik, 2002). Diagnosis is often difficult, however, since it is unlikely that the physician will actually see the patient experience and epileptic seizure, and therefore must rely heavily on patient’s history. An electroencephalography (EEG) is often used to examine the patient’s brain waves, and some forms of epilepsy can be revealed by a characteristic disturbance in electrical frequency (Bassick, 1993). The variations in frequency can take form as spikes or sharp waves (Fisher, 1995). The variations are divided into two groups, ictal electrograph abnormalities, which are disturbances resulting from seizure activity, and interictal electrograph abnormalities, or disturbances between seizures. The EEG can also give clues as to which region of the brain the disturbances arise from. Interictal temporal spikes will predict the side of seizure origin in 95% of patients if three times as ...
Most of the noninvasive imaging methods estimate brain activity by changes in blood flow, oxygen consumption, glucose utilization, etc. Discuss the potential problems with using this type of indirect measure.
Kawasaki et al. (2001) explored the relationship between emotional sensory stimuli and the prefrontal cortex. They looked at neuron response in a 48-year old epilepsy patient using depth electrodes to record neuron activity. They found a short latency to aversive stimuli in the ventral prefrontal cortex.
Assistive technology is often used by individuals with a learning disability. A learning disability “describes a neurobiological disorder in which a person’s brain works or is structured differently” (Lee1). A person’s abilities can be severely affected from a learning disability. They may listen differently, talk differently, write, spell, organize, and work with school subjects in a different way. Learning disabilities also affect people’s individual and personal lives to a great extent. According to the National Institutes of Health, one in seven children has a learning disability. The disability manifests itself when the child shows difficulty in reading, writing, spelling, and conversing with others. The added time they need to process information may make them seem less intelligent then others around them, but this is not the case. Individuals with learning disabilities are just as smart as anyone else; they just need to learn in a different way. The earlier a learning disability is noticed and detected, the earlier a child may be able to learn how to deal with or compensate for it (Lee 1). This is where assistive technology comes into play.
In all the research and projects so far have been made with this method (Brain computer interface), all subject controlled by a person brain, an example of the research that has been done by Millan et al. [4] was on mobile robots has been controlled by a person brain. Or control the electrical wheelchair made a non-invasive method by thinking about it that the person was able to move between rooms [3].
Moreover, EEG provides a direct and real time measurement of neural activity. The temporal resolution is of the order of a few milliseconds, which allow rapid changes in cortical function to be followed. On the other hand the spatial resolution is relatively low (6, 7).
The Principles of Psychology. Toronto, Ontario: York University. L. R. Hochberg, M. D. (2006). Neuronal ensemble control of prosthetic devices in a human with tetraplegia. Nature, 164-71.
The mouse motion can be slowed down for better control. The toolbar can be created to suit the children's needs. However if this is not suitable there are many peripherals and devices, which can support children with SEN, but not all are appropriate for everyone. For those children with a physical disability a variety of switches, optical pointers, voice controlled devices and word prediction software has been designed to overcome the problems these children have using traditional input devices such as the mouse and keyboard.
In the past few decades we have seen how computers are becoming more and more advance, challenging the abilities of the human brain. We have seen computers doing complex assignments like launching of a rocket or analysis from outer space. But the human brain is responsible for, thought, feelings, creativity, and other qualities that make us humans. So the brain has to be more complex and more complete than any computer. Besides if the brain created the computer, the computer cannot be better than the brain. There are many differences between the human brain and the computer, for example, the capacity to learn new things. Even the most advance computer can never learn like a human does. While we might be able to install new information onto a computer it can never learn new material by itself. Also computers are limited to what they “learn”, depending on the memory left or space in the hard disk not like the human brain which is constantly learning everyday. Computers can neither make judgments on what they are “learning” or disagree with the new material. They must accept into their memory what it’s being programmed onto them. Besides everything that is found in a computer is based on what the human brain has acquired though experience.