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Answering the question what is needed for a human brain to evolve starting from a cephalopod brain is hard. However, I can expand on what is thought to have been the driving forces behind the evolution of the humanoid brain (Hawks, 2013): The species of the famous Lucy fossil, Australopithecus afarensis (~3-4 mln yrs ago), had skulls with internal volumes ...


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The mind is an abstraction which arises from physical and chemical processes within the brain. For a crude analogy, think of the brain as an incredibly complex, self-modifying, multithreaded program. The mind would then be the abstraction arising from the behavior of the program as it runs. Consciousness would be the abstraction arising from the behavior ...


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Short answer SSVEP frequency corresponds to stimulus frequency and SSVEP amplitude decreases with stimulus frequency. Background The simplest form of steady state visual-evoked potentials (SSVEPs) are those to flash stimuli. Herrmann (2001) studied the SSVEP by recording the EEG from the visual cortex at various flash frequencies. He found that SSVEPs ...


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I think that the type of fMRI you are referring to is blood-oxygenation-level-dependent fMRI or BOLD fMRI. The principle behind MRI in general is the detection of proton signals from water molecules. The proton signal is generated by magnetizing the protons in tissue, which causes their spin to change. A subsequent powerful radio wave disrupts this spin ...


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Firstly you have to take into consideration that nociceptors do not adapt to stimulus. This means that a nociceptor will not only fire at the beginning of the stimulus, as seen in mechanoreceptors that have phasic responses, but will fire as long as the stimulus lasts. This type of response is called tonic response (see figure). Figure A shows the tonic ...


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Pain receptors, more precisely pain signal propagation, can be inhibited in several ways. One is, for example, fine touch receptors (mechanoreceptor in illustration) inhibit propagation of pain signal in spinal cord (a lot of pain processing happens in spinal cord): That is why humans often rub skin around or nearby injury, whether it is in joints or ...



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