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As far as I know, it is not possible for a neuron to change which type of neurotransmitter it releases. However, it is the case that the neurotransmitter GABA changes from excitatory to inhibitory over the course of development. This is occurs because GABA activates Cl- (chloride) channels. The chloride concentration gradient across the cell membrane ...


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The textbook convention is that neurons release only one type of chemical from their synaptic terminals. This is known as Dale's Principle (https://en.wikipedia.org/wiki/Dale%27s_principle), and would exclude the possibility that neurons can release both inhibitory and excitatory neurotransmitters. Examples have been found of neurons which co-release two ...


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Basically there are two reasons. First, (most) synapses are asymmetrically designed in such a way that synaptic transmission only works in one direction. Second, action potentials usually run in one direction only, from the axon hillock down the axon. Saying that a neuron fires means that an action potential (AP) is effected, a series of depolarisations ...


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I found that dF/F0 stands for the relative difference in fluorescence at a certain wavelength.


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There are many transformations between the light hitting your retina and your perception of the world. The signals from your retina initially travel through the visual pathways to reach your visual cortex, where visual information is processed. The representation of this visual information in your brain is also shaped by other brain activity representing ...


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It is not the case that the brain flips the retinal image, nor does it have to, nor are there any images in the brain like there are on the retina. It is just as meaningless to say that the retinal image is upside down in relation to the orientation of our perceptions. Richard L. Gregory gives a nice explanation: It is generally accepted that this does ...


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Probably not. STDP has mostly been demonstrated in excitatory glutamatergic neurons in the hippocampus. Considering all the other types of cells in the brain (dopaminergic, serotonergic, inhibitory, those located in cortical areas with closed plasticity windows those in the brain stem), it's erroneous to assume they all implement STDP like rules. That said, ...


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This isn't exactly what you are referring to, but I think provides a similar function and has been shown in vertebrate vision: https://en.wikipedia.org/wiki/Normalization_model Divisive normalization as a canonical computation across the brain While this does not implement histogram equalization, I think it is actually a better-suited explanation of the ...


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MRI Spectroscopy is another method for measuring neurotransmitters in the living human brain. Here are some examples: Dopamine Reduction in the Substantia Nigra of Parkinson's Disease Patients Confirmed by In Vivo Magnetic Resonance Spectroscopic Imaging Direct detection of brain acetylcholine synthesis by magnetic resonance spectroscopy



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