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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 parts. First of all, there are the action potentials (APs). APs are current flow within a neuron from one end to the other. The magnitude of these APs (and ...


11

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 differences represent electric fields and do not represent electromagnetic (EM) radiation. EM radiation is build up of packets of energy (photons). EM radiation ...


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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 found by Berger was controversial, over the years many researchers replicated the results, which led to the acceptance of EEG as a real phenomenon. Neurons Before ...


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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 potential without creating an electromagnetic wave. You can try browsing wiki explanation https://en.wikipedia.org/wiki/Maxwell%27s_equations, but the main idea is ...


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Techniques that measure brain activity at a distance such as EEG and MEG measure spiking activity very poorly and indirectly. Instead, these techniques primarily measure synaptic currents. Synaptic currents of course originate in some way from spiking activity, however: Synaptic currents may not occur in the vicinity of the spiking cells The amplitude of ...


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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. Because of this, MEG is largely insensitive to sources oriented radially, but can pick up sources oriented tangentially to the cortex. Moreover, EEG is sensitive to ...


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MEG measures magnetic fields and EEG measures electrical potentials. One property of magnetic fields is that organic matter (scalp, skull, and brain) does not block them in any significant way. Electrical potentials measured on the scalp, on the other hand, are definitely affected by the matter between the source of the signal and the location they are ...


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Apart from making the distinction between recording techniques (talking about N170 and you refer to ERP), here is an explanation: Naming convention refers more to neurophysiology than waveform (component) directions. The standard tool modeling the EEG/MEG activity is a dipole. A dipole consists of a pair of a negative and positive charges and it generates ...


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You have one p-values for each ROI timecourse (for the largest cluster) indicating whether your conditions are exchangeable. If you want to correct for the 4 ROIs you could use any adequate multiple comparison correction, from classical Bonferroni (which might be too conservative as the tests are likely not completly independent) to Benjamini-Hochberg style ...


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