170 likes | 294 Views
Billy Vermillion. Brain-Computer Interfacing. EEG. Electroencephalography A test to measure the electrical activity of the brain. Brain cells communicate by producing tiny electrical signals, called impulses. Flat metal disks called electrodes are placed all over your scalp.
E N D
Billy Vermillion Brain-Computer Interfacing
EEG • Electroencephalography • A test to measure the electrical activity of the brain. • Brain cells communicate by producing tiny electrical signals, called impulses. • Flat metal disks called electrodes are placed all over your scalp. • Held in place with a sticky paste or specially designed helmet. • Connected by wires to a recording machine. • The recording machine filters the signals into patterns that can be seen on a computer.
Brain-Computer Interface (BCI) • Current BCIs have maximum information transfer rates up to 10-25bits/min • A BCI depends on feedback and adaptation of brain activity based on that feedback • Operation depends on the interaction of two adaptive controllers: • The user’s brain • Which produces the signals measured by the BCI • The BCI itself • Which translates these signals in specific commands
BCI BCI2000: A General-Purpose Brain-Computer Interface (BCI) System GerwinSchalk*, Member, IEEE, Dennis J. McFarland, ThiloHinterberger, NielsBirbaumer, and Jonathan R.Wolpaw
P300 • Infrequent or particularly significant auditory, visual, or somatosensory stimuli • Interspersed with frequent or routine stimuli • Evoke in the EEG over parietal cortex a positive peak at about 300ms latency • Only the choice desired by the user evokes a large P300 potential • Requires no initial user training • P300 is a typical, or native, response to a desired choice
Steady-State Visually Evoked Potential (SSVEP) • Natural responses to visual stimulation at specific frequencies • When the retina is excited by a visual stimulus ranging from 3.5 Hz to 75 Hz, the brain generates electrical activity at the same (or multiples of) frequency of the visual stimulus. • Used widely with research regarding vision • Excellent signal-to-noise ratioand relative immunity to artifacts. • SSVEP's also provide a means to characterize preferred frequencies of neocortical dynamic processes.
SSVEP http://www.youtube.com/watch?v=9afbMN1lPZE Design and Implementation of a Brain-Computer Interface With High Transfer Rates Ming Cheng*, XiaorongGao, ShangkaiGao, Senior Member, IEEE, and DingfengXu
Combination http://futuristicnews.com/wp-content/uploads/2012/10/mind-controlled-leg-robotics-EEG-2.jpg
Signals http://scienceblogs.com/thoughtfulanimal/wp-content/blogs.dir/351/files/2012/04/i-7cb3dec9973ac6a5143c37eb9efce18b-motor%20somato.jpg http://www.brain.riken.jp/bsi-news/bsinews34/files/research0103-big.jpg
fMRI http://scienceblogs.com/developingintelligence/wp-content/blogs.dir/411/files/2012/04/i-8df6cca3f243ab02d498057e053ff30b-fmri_image.jpg
http://mialab.mrn.org/software/fit/images/fmri_fmri_fusion.jpghttp://mialab.mrn.org/software/fit/images/fmri_fmri_fusion.jpg