AIST Stories No2
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17Into the future AIST!A brain wave is detected and a decision is identified within secondsThe electroencephalogram of the Neurocommunicator is very compact, about half the size of a mobile telephone. Eight channels of brain waves can be measured at the scalp simply by the patient wearing a cap in which the electroencephalograph is incorporated.The patient selects the idea they want to express from a thought expression menu displayed on a computer screen. An initial display shows pictures and text labels for broad categories of thoughts, such as food/drink, movement, body care, and feelings. When one of these is selected, a menu of more specific items is displayed. By proceeding through the sequence of menus, the patient can express precise requests and feelings.Dr. Hasegawa explains: "Which item has been selected can be identified by analyzing the brain waves. The candidate items are randomly highlighted, and when the selected candidate is highlighted, the brain responds with a 'Yes!' The change in brain waves that this causes is the key to identification. The brain waves are analyzed with a specific decoding algorithm; this algorithm quickly and accurately infers the patient's decision in the brain."Many previous developers of communication aid based on brain wave-based BMIs (sometimes called Brain-Computer Interfaces: BCIs) focused on methods of inputting words one character at a time. With these previous technologies, a single selection usually takes ten seconds or more. Moreover, the longer the message that the patient is trying to convey, the longer the time needed for brain wave measurements and the more often erroneous selections are made. In contrast, the Neurocommunicator requires only three to five seconds for one selection (from eight options), regardless of the length of the message. Repeating the process just three times makes it possible to select from 512 (83) messages. The decoding accuracy is good, at more than ◦Food‌◦Residential◦Information technology◦‌‌Medicine, welfare, caregiving◦Services◦IT and Telecommunications◦Electronics◦Medicine90%.In addition, the way thoughts are conveyed is user-friendly, with an avatar selected to represent the user appearing on the screen and speaking. This means that more natural communication is possible.Working toward a practical implementation soon!The places the Neurocommunicator will be used are ordinary homes and hospital rooms, which are affected by various kinds of electronic interference from air conditioners, refrigerators, etc. It is difficult to measure tiny brain waves in these environments, but Dr. Hasegawa and his staff are devising a unique new electronic shielding system to overcome this problem. Since his initial announcement, he have had a flood of enquiries from the families of incurable patients; clearly, there is a compelling need for this equipment in the fields of caregiving and welfare support. He has now completed a prototype for clinical studies; tests were started with monitor patients with the latest version of the equipment in the spring of 2014.Dr. Hasegawa says "There has been a greater range of problems than I initially expected and development has been slow, but we are working hard to achieve a practical implementation soon. The Neurocommunicator is still regarded as an 'amazing' technology, but my hope is that some day it will be a familiar thing, simply improving the connections between people."*1 Brain–Machine Interface (BMI): A general term for devices that directly connect a brain with a machine. These can be broadly divided into invasive types, which use an intracranial implant to record brain activity and/or provide electronic stimuli within the brain, and non-invasive types, which measure neural activity such as brain waves from the scalp. The Neurocommunicator is one of the latter.▲‌‌Brain wave data is decoded while the user wearing the headgear is concentrating on one of the pictograms linked to specific messages on the monitor. From the result of the decoding, the desired message is inferred and is expressed by the avatar.(3) A decision in the brain is decoded quickly and accurately(4) A message is conveyed by an avatarPlease turnme onto myleft side.When the target pictogram (focus of the user) is highlighted, brain waves known as an "event-related potential", especially “P300” component appears. The system can decode the target pictogram by detecting the P300.The user concentrates on one of eight options displayed on the monitor screen.Event-related‌potential‌(P300)Time passingThe options are highlighted in a pseudo-random order, with being flashed up on each one.An example of a thought expression menuHow the Neurocommunicator is operated(1) Candidate messages on a screen are successively highlighted(2) Brain waves are measured at the scalp by a compact electroencephalographImpact in the following fields! Community lifeIndustry

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