17
votes
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Are brain waves electromagnetic waves?
Short answer
Brain waves are not electromagnetic waves.
Long answer
Measured brain activity, as you already mentioned, is the result of individual neurons firing. The activity exists, in fact, of two ...
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12
votes
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Is there a way to make a DIY EEG?
The OpenEEG project has some information for building your own EEG system. Instructables has a "simple" EEG circuit you can build. Note that this is going to be somewhat costly and time consuming ...
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11
votes
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What happens in your brain when you see a dinosaur in this stenographic image?
The source I have quoted below gives an example of the following stenographic image:-
Is this perception a particular trick that my eye performs or is it processing the visual data in an alternative ...
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11
votes
Are brain waves electromagnetic waves?
Short answer
Brainwaves are typically associated with the electroencephalogram, which is a signal mainly composed of potential differences generated in the superficial layers of the brain. Potential ...
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10
votes
What do brain waves look like under the influence of psilocybin?
Best start here: The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs (2014). And then here is some more current literature worth exploring:
Neural ...
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8
votes
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What are proper EEG frequency bands and electrode placements for imagined speech?
A study by D’Zmura et al. (2009) in which two syllables were spoken in imagination showed that imagined speech information was present in EEG alpha, beta and theta bands. The beta band (13-18 Hz) ...
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8
votes
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Do alpha waves vanish when I open my eyes in a dark room?
Yes they do.
That is to say, light conditions do not generally affect alpha waves, only the eyelids do (and other factors). This has led to alpha waves being interpreted as reflecting an active ...
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8
votes
Are brain waves electromagnetic waves?
If "brain waves" produce a time-varying electric potential as shown on the EEG, then as far as I know electromagnetic waves are present. I was taught that you cannot have a time varying electric ...
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8
votes
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Physiology behind EEG measurements
EEG research all started with Hans Berger, who in 1929 reported that brain activity could be recorded by measuring electrical activity on the scalp. Although the notion of ‘brain waves’ that were ...
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7
votes
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Why is the order of brainwaves not labelled "alphabetically"?
They are ordered based on when they were discovered/named (as pointed about by Ana's comment). Alpha and beta waves were among the first signals observed in EEG data. From Wikipedia:
Alpha waves ...
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6
votes
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Mapping Sustained Attention on the brain (EEG)
You should consider using subject-specific alpha channels and frequency ranges. There are differences between individuals in alpha peak frequency. Also the placement of the EEG cap as well as small ...
5
votes
Are there any EEG procedures currently available/in development that can formulate letters/words from deliberate, internal monologue?
What you are looking for is Imagined / Silent Speech Classification (my best guess). I'm interested in this for a few years (exactly to work with Vim) now and worked with some of the cheap EEG ...
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5
votes
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Can fMRI and EEG signals be generated from NEF models?
Replicating fMRI signal was first used in the Tower of Hanoi task as seen in section 5.8 of "How to Build a Brain":
There is strong evidence that dendritic processing, driven by
neurotransmitter ...
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5
votes
Getting started with EEG data
If you are considering an alternative to matlab that is free I would recommend octave. If you are on linux you might consider the whole neurodebian. In terms of book I did not find Steve Luck's book ...
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5
votes
How do I obtain recordings of the P300 wave of the event-related potential in the EEG?
The P300 wave is a positive deflection in the human event-related potential (ERP). A common experiment in which it is analyzed is the "oddball" paradigm, where a subject detects an occasional target ...
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5
votes
Does stimulus-independent ERP make sense/ exist?
An ERP is an Event Related Potential, making it inherently connected to an event. Having stimulus/response independent ERPs is thus impossible. There do exist potentials that seem to be stimulus ...
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4
votes
How does the alpha brain wave frequency range distribute over the population?
Alpha oscillations vary in frequency within a single subject from brain area to brain area (Başar, 2012), likely because there is not a single phenomenon underlying all examples of alpha oscillations....
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4
votes
Cost of EEG devices suitable for neurolinguistic research
An old question, but there has been some recent developments by third-parties and now cheaper and hopefully just-as-accurate EEGs exist.
From Are recent affordable EEG devices any good? we see the ...
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4
votes
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Neurophysiological indications of focus and motivation
Focus and motives are very different cognitive processes. Essentially focus would be attention, while motivation is a complex neurocognitive process, such as hunger or thirst, which drives attentional ...
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4
votes
EEG Alpha waves during eyes open mindfulness training - any research on this subject
There are many studies suggesting an increased alpha activity during mindfulness/meditation (Delmonte, 1984). Below is a table from Cahn & Polich (2006) summarizing the recent studies of ...
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4
votes
Are there any EEG procedures currently available/in development that can formulate letters/words from deliberate, internal monologue?
I can respond a little to your second question, in particular as it related to EEG: What is the current state of progress regarding the formulation of useful information from neural firing patterns ...
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4
votes
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Conducting brain stimulation at home
At the moment, there are no TMS/tDCS protocols that were approved for the home use in USA or EU. So, please, don´t. Fortunately, TMS devices are quite expensive and cannot be used by a single man. ...
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4
votes
Component naming of MEG vs. EEG
EEG and MEG measure two different but related signals. While EEG records the electric activity from the scalp, MEG records changes in the magnetic field induced by electric activity in the brain. ...
- 101
4
votes
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In what order do you preprocess EEG data?
You kind of have to do some kind of baseline correction first (or a highpass filter on the unepoched data) because of slow drifting. Lowpass filtering before artifact rejection is fine as long as you ...
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4
votes
What is the meaning of the peak polarity in EEG data?
Short answer
The peak polarity of an EEG is arbitrary.
Background
Positive and negative in an EEG measure is arbitrary. If you measure the EEG between two electrodes and you flip the wires, the ...
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4
votes
Does stimulus-independent ERP make sense/ exist?
Resting state EEG protocols already exist, but they do not focus on ERPs (thus solving your problem). You can assess coherence between pairs of electrodes (if you enter 'resting state EEG' into google ...
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4
votes
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How to calculate absolute power for EEG from power spectra density?
I had to do some searching to be able to answer this question. As a matter of fact, a similar questions was once asked on Signal Processing.
To make the explanation more laymen-like, I think the ...
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4
votes
Accepted
What does "diffuse slowing" mean in the context of EEG and Alzheimer's?
Medscape defines diffuse as generalized, in the context of EEG. Generalized means activity recorded across large portions of the cortex. This opposes focal patterns, that occur locally. In turn this ...
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4
votes
Why are biosignals from the body said to be continuous?
Biological signals are analogues and hence continuous. Early EEG systems simply recorded the analogue signals and displayed it as a continuous signal graphically as wiggly lines written by little pens ...
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Only top scored, non community-wiki answers of a minimum length are eligible