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ABSTRACT
As the power of modern computers grows alongside our understanding of the human brain, we move ever closer to transforming some spectacular science fiction into reality. Imagine transmitting signals directly to someone's brain that would allow them to see, hear or feel specific sensory inputs. Consider the potential to manipulate computers or machinery with nothing more than a thought. It isn't just about convenience - for severely disabled people, development of a brain controlled interface or brain-computer interface (BCI) can easily be called the most important technological breakthrough in decades.
CHAPTER ONE
GENERAL INTRODUCTION
1.1 BACKGROUND OF STUDY
Some years ago, the lives of completely paralysed patients automatically ended due to the restricted (and in most cases, lack of) movement of the affected areas. Later, it was realized that as long as the parts of the brain controlling those affected areas weren’t damaged during the accident, the brain signals for those affected areas were still fully functional. This discovery opened up a world that had lived only in the minds of the science fiction dreamer, giving victims of debilitating injuries something to put their hopes on (Wolpaw et al., 2000).
1.2 STATEMENT OF STUDY
This study has many statements as described by the different groups of scientists who embarked on this study but the summary of them all is:
“To create a union between the human body and the computer that will herald mankind to a higher level of living and give him a better understanding of himself”.
1.3 OBJECTIVE OF STUDY
The human body is one of the most complex (if not the most complex) entities and has been a well-researched topic. This study is geared towards creating a feasible relationship between the human body and a computer system which will, of course, make human living a lot more comfortable and sophisticated.
1.4 SIGNIFICANCE OF STUDY
This study has many significances but the most significant of these significances is the medical aspect, which entails controlling a device e.g. computer, wheelchair or a neuroprothesis by human intention which does not depend on the brain’s normal output pathways of peripheral nerves and muscles (Wolpaw et al., 2000).
1.5 LIMITATION OF STUDY
1. The equipments needed are expensive, with the cheapest as expensive as $5,145 (which is approximately equivalent to N771, 750).
2. In the case where a device (even one as tiny as a logic gate) is been implanted on the brain, the medical procedure is very delicate and complications can arise practically from nowhere in the twinkle of an eye.
3. Lack of awareness and fear of its long-term effects have discouraged a lot of patients from becoming willing ‘guinea pigs’,
4. Specialists that are experienced enough to carry out the necessary operations are few due to the fact that this study is still being researched.
5. There are about 100billion neurons in a human brain. Each neuron is constantly sending & receiving signals through a WEB of connections. This makes designing a device as seemingly simple as an arm having grippers (in place of fingers) difficult.
Fig, 1: Grippers attached to a prosthetic arm
Source: Howstuffworksbrain_computer_intrerface
6. EEG measure tiny voltage potentials, and sometimes a simple as the blinking eyelids of the subject can generate much stronger signals than can be read by the EEG.
7. Some brain controlled interfaces still require a wired connection to the equipment, & those that are wireless require the subject to carry a computer that can weigh around 10pounds.
1.6 ORGANIZATION OF STUDY
A typical brain controlled interface is
CHAPTER TWO
LITERATURE REVIEW
2.1 HISTORICAL BACKGROUND
In 1848, Duboi-Reymond reported the presence of electrical signals in the human brain. Research on this led to Caton’s discovery in 1875 that “feeble” currents can be measured on the scalp. In 1924, Mr Hans Berger discovered the EEG ( ), a device that theoretically measured electrical signals. However, this wasn’t proven until 1929 by Berger. He analysed the interrelation of EEG and brain diseases
o Berger (1929) measured electrical signals with EEG
o 1930-50s EEG used in psychiatric and neurological sciences relying on visual inspection of EEG patterns
o 1960s-70s witness emergence of Quantitative EEG and confirmation of hemispheric specialization, e.g., left brain verbal and right brain spatial.
o 1980s+ observation of biofeedback
• 1970: First developments to use brain waves as input
• ARPA has vision of enhanced human
First step in the right direction
• 1990: First successful experiments with monkeys
• Implanting electrode arrays into monkey brains
• Recording of monkeys‘ brain waves
• 2000: Monkeys control robots by thoughts
• More non-invasive than invasive approaches
• Brain reading by eg. EEG, MEG or fMRI
• 2004: First human benefits from research
Early research used monkeys with implanted electrodes. The monkeys used a joystick to control a robotic arm. Scientists measured the signals coming from the electrodes. Eventually, they changed the controls so that the robotic arm was being controlled only by the signals coming from the electrodes, not the joystick. By 2000, the group succeeded in building a BCI that reproduced owl monkey movements while the monkey operated a joystick or reached for food.
In May 2008 photographs that showed a monkey operating a robotic arm with its mind at the Pittsburgh University Medical Centre were published in a number of well known science journals and magazines.