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Ohm's law famously states V=IR, the voltage change (V) across a resistor generated by a current (I) equals the current multiplied by the resistance (R). The resistor in this case is the cell membrane. When an experimenter injects a known amount of current through an electrode, the voltage change that occurs is related to that current by the resistance of ...


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The distance of horizontal communication depends on species, cortical region, and cortical layer. Very few combinations of those 3 factors have ever been studied. For the combinations with which I am familiar, most horizontal connections are limited to a few hundred microns, though some are as long as a few millimeters. Most of that distance is axonal ...


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Probably, the "oscillation" refers to the signals of eeg/ecog/meg? If this is the case, then the answer is NO, individual neurons in a local network are firing with much higher rate then the frequency of the oscillatory field produced by the network. (Otherwise, the oscillations would look more like a ripples, not like the periodic function.) The exact ...


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Myelin is a greatly extended and modified plasma membrane wrapped around the nerve axon in a spiral fashion (Morell & Quarles, 1999). It typically forms on long axons to increase conduction speed and efficiency. Learning predominantly takes place in cortical areas and it is believed that it mainly depends on synaptic changes, such as long-term ...


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Short answer Based on a dated and small study, early-blind individuals do not experience drug-induced hallucinations, while the late-blind can, but not necessarily do so. Background Krill et al. (1963) investigated the effects of LSD on totally blind people (i.e., no residual vision) and they report visual hallucinations in 13 out of 24 subjects. This ...


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No. For example, the neurotransmitter at the first stage of auditory processing (the inner hair cell VII cranial nerve synapse) and visual processing (rod and cone synapses with a bipolar cells) is glutamate.


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The general consensus of the scientific community would be that the human heart is not capable of consciousness. The machinery behind consciousness is not well understood, of course, and there is quite a bit of debate, but it is thought that some minimum level of complexity is required in order for consciousness to arise. The human heart, while containing ...


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Quoting my thesis: CNS Dopamine/DA projections primarily emerge from two subcortical basal ganglia nuclei in the brain stem, travelling along three major pathways (Purves et al., 2004). The nigrostriatal pathway, connecting the substantia nigra and the striatum, is mainly implicated in higher motor control. The mesolimbic pathway contains DA ...


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Parts of the brain affected by dopamine Dopamine exerts different effects in different regions and pathways throughout the brain. In the mesolimbic pathway, dopamine is believed to be involved in motivation and addiction due to the feelings of reward and pleasure associated with dopamine release here. In the mesocortical pathway, dopamine is linked to ...


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Actually it's a bit complicated but in simple terms : Neurotransmitters are stored in a synapse in synaptic vesicles, clustered beneath the membrane in the axon terminal located at the presynaptic side of the synapse. Neurotransmitters are released into and diffused across the synaptic cleft, where they bind to specific receptors in the membrane on the ...


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No, unlike norepinephrine and serotonin, dopamine's pathway is limited.actually it affects two part of cognition, reward and motor functions. As part of the reward pathway, dopamine is manufactured in nerve cell bodies located within the ventral tegmental area (VTA) and is released in the nucleus accumbens and the prefrontal cortex. The motor functions of ...


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yes, see de Almeida, et al., 2009 for a biologically plausible implementation http://www.jneurosci.org/content/29/23/7497.short


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Also FieldTrip for Matlab, and MNE for Python


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Is it known whether the connection strength of synapses is important to the functioning of the brain or does just the binary existence of a synapse matter? I think it's safe to say that neuroscience, as a field, would stand behind this statement from neurobiologist David Sweatt, in his excellent 2003 (1st edition...2nd is probably even more current) ...


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The commenter below alerted me to the existence of autapses, which apparently are chemical synapses between a neuron and itself. So those clearly exist. At the same time, it does seem that there is a mechanism that would suppress self-synapses: a protein called Dscam that acts during neuronal development. Dscam is a membrane protein that can form a high ...


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Check it: https://en.wikipedia.org/wiki/Long-term_potentiation In other words, yes, the strength of synapses matters. A synapse that has been potentiated means that the postsynaptic neuron will fire more readily as a function of the stimulation from the presynaptic neuron. As for how widely the strengths vary, I have to admit I'm not quite sure how to ...



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