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It's important to clarify what an EEG machine measures. Electromagnetic waves are photons. An EEG does does not detect radiation. It detects magnetic fields by measuring an electrical current induced in the measuring device by the brain. Electricity is the movement of electrons. Electromagnetic waves are photons of light. Magnetism a force which fills ...


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I assume with EM you refer to electromagnetic? You are right that the EEG (electroencephalogram) is a tiny signal. When about 50.000 neurons fire simultaneously, it possible to see a change in the measured signal. Typical EEG amplitudes are in the microvolt range. Now, when the EEG is recorded, it is a function of time. You could for example collect data ...


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I noticed that a strong background signal in the alpha-wave range was existent at ~10 Hz, but then after a while of doing other things and coming back to it the strong background signal at 10 Hz disappeared but a strong background signal at a smidgen over 8 Hz was present instead. Alpha-waves (7-13 Hz) are related to a dozen of things. Here is an easy ...


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You might want to read about event related potentials (recorded by EEG) or event related fields (recorder by MEG). The idea is simple: 1) Pick some stimulus, e.g. a person touching the hand of a subject. Pick another stimulus, e.g. the subject seeing a person touching the hand of another subject. Record EEG/MEG. 2) Repeat each condition for at least few ...


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Pressing on the chest changes the concentration of dissolved gasses in the blood stream. Your brain reacts due to excessive oxygen in the blood. This is oxygen toxicity. Why the brain generates vivid imagery when unconscious is a big topic. There's a theory that correlates dreams with a lack of cognitive stimulation. This is called autostimulation and may ...


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I think this is mostly caused by hyperventilation. The excessive breathing disturbs the balance between CO$_{2}$ and oxygen in our lungs. This will cause a http://en.wikipedia.org/wiki/Respiratory_alkalosis (the blood pH, which is normally strictly regulated, gets higher), which can cause dizziness, headaches and fainting. The shift in pH can also disturb ...


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Strictly stated, Hebb's rule applies only to existing synapses, and not to the formation of new synapses. (This answer applies to biological neurons, not to ANNs). Synapse formation is a topic of active research. During development (and in fact continuously even during adulthood), many synapses are created and destroyed. It is not unreasonable to suspect ...


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Keegan's answer is good I gave it an up vote. I want to offer a valid alternative. Psychology may induce redundant pathways which trigger approximate simultaneous firing of neurons near or in completely different parts of the brain. Emotionally intense memories can trigger emotions, basically hallucinations of the event, smells and touch based ...



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