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In this section are a description of how we processed raw EEG data, as well as an overview of how we algorithmically distinguished between the data associated with resting and reading.

The algorithm

After collecting a large amount of data related to different activities and, in theory, different levels of brain activity, we attempted to make general statements about the differences between them. Nearly all of the data we collected revealed that distinct activities resulted in distinct brain signals; however, some of these differences appeared more reliably and more markedly than others. By examining the spectrograms we created for each scenario, we determined that relaxing and reading were two of the most distinct activities with respect to measured brain activity. With this in mind, we decided to design and implement an algorithm capable of distinguishing between spectrograms associated with relaxing or reading.

The initial step in this process was an analysis of the spectrograms and power spectral density plots collected for different trials of reading and resting. Several features seemed potential candidates to be leveraged in the algorithm. One striking difference is the presence of an intense band of activity at 120 Hz, which appears in the reading spectrogram but is absent in the resting spectrogram. Despite its stark differences, we chose not to incorporate this feature into the algorithm because we felt that it does not likely indicate a true effect occurring in the brain. Rather, its ubiquity across many of our measurements (and the fact that its frequency never wavers) led us to believe that it might be an artifact of the headset. Instead, we were more interested in the fact that the resting state appears to have more energy just above baseband, in the 10-50 Hz range. Ultimately, this was the feature we selected for in the algorithm. Because this is an effect that accumulates over the entire period of the experiment, the Power Spectral Density plot provides an excellent way to quantify these differences. As is evident in the PSD plot below, the intuitions we developed from the spectrograms are clearly confirmed to hold true for the example below. After inspecting several other trials, we decided that the 10-50 Hz frequency range selected the phenomenon we observed while excluding potential sources of noise like 60 Hz noise. Thus, we wrote a script to integrate the power in this range for the two sets of data. It then attributes the higher value to the resting state and the lower to a reading state. With the appropriately set integration limits. the algorithm correctly determined the source of the data for all of the trials we performed.

A psd comparison of reading and resting

example psd plot

Questions & Answers

Application of nanotechnology in medicine
what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
Damian
yes that's correct
Professor
I think
Professor
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
LITNING Reply
what is a peer
LITNING Reply
What is meant by 'nano scale'?
LITNING Reply
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
Rafiq
if virus is killing to make ARTIFICIAL DNA OF GRAPHENE FOR KILLED THE VIRUS .THIS IS OUR ASSUMPTION
Anam
analytical skills graphene is prepared to kill any type viruses .
Anam
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
Adin
why?
Adin
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
Praveena Reply
hi
Loga
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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Source:  OpenStax, Characterization of eeg signals from neurosky mindset device. OpenStax CNX. Dec 19, 2011 Download for free at http://cnx.org/content/col11392/1.1
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