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No, inner speech does not follow the same neural pathway as speech coming in from outside. Rather, inner speech uses the same neural mechanism as outer speech - that is, speech going out. The neural mechanisms of inner speech can be studied using recently developed technologies such as fMRI imaging of subjects instructed to or prevented from engaging in ...


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Short answer Hair cells in the cochlea can code sound intensity via the amount of neurotransmitter they release. Higher sound levels result in more neurotransmitter release and in turn to higher firing rates in the spiral ganglion cells of the auditory nerve. Background Sound waves are picked up by the mechanoreceptors in the inner ear: the hair cells. ...


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Perhaps this is not what you asked, but there's a phenomenon called rebound spiking or postinhibitory spiking where a hyperpolarization causes spiking. This is due to the oscillatory property of membrane dynamics (certain subsets of type-II neurons). Spikes can be evoked after inhibitory current stops. Figure 7.29 from Izhikevich's book: Here's a partial ...


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Short answer Stereoscopic vision is the perception of depth via disparity. Disparity is the mechanism that the visual system uses to create binocular depth perception. Background A dictionary definition of Stereoscopic is the following: [N]oting or pertaining to three-dimensional vision or any of various processes and devices for giving the illusion of ...


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In principle, no. An action potential is initiated due to the activation of Na+ channels. These are so-called voltage-gated channels, meaning that they sense a depolarization and subsequently open their Na+ pore to allow Na+ to flow in, further depolarizing the cell. This is the depolarizing phase of an action potential. voltage-gated K+ channels open up ...


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Short answer Symptoms of hemi-neglect are often accompanied by additional layers of cognitive deficits that make rehabilitation challenging. Logic reason is often dissociated from these patients' perceptions, or they simply dismiss there is a problem altogether. Background Hemineglect is the impaired or lost ability to react to, or process sensory stimuli ...


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Current is Voltage (driving potential) times conductance. As the membrane potential approaches the Nernst potential of the conductance, the current approaches 0. Conductances can be turned on or off through receptor binding, but there is no such thing as voltage-independent current injection (at least under physiologically relevant conditions). Indeed, ...


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Short answer: Probably not. Let's first keep in mind that very few split-brain patients have ever been studied. Add to this that inner speech is not a well studied area in general. As the resulting Venn diagram suggests, there is next to nothing known about inner speech in split-brain patients. Second, remember that one of the key reasons why inner ...


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Diffusion tensor imaging (DTI for short) may be the technique you are after. It is able to record nerve fibers in MRI images. I couldn't find the specifics you were after, and the subdivision into layers may outrun the resolution of MRI, but it may be a good start. Two references that may get you going on tensor imaging are cited below. Additional, ...


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Short answer The dreaded it depends. Background This question was discussed behind the scenes in chat and we concluded with the consensus on explaining why this question is hard to answer. Basically, you are asking on the suppressive effects of oxytocin on the brain. First, it depends highly on the brain area under investigation. Many, and perhaps all ...


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Short answer Muscles are controlled by motor neurons in the spinal cord. The number of motor neurons that fire, as well as their individual firing rates govern the control of muscle force. Background Muscles consist of contractile elements: the muscle fibers. These muscle fibers are under direct control of the motor neurons in the spinal cord (Purves et al.,...


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Dopaminergic neurons synthesize dopamine and release it at their synapses with target neurons (see David Sulzer's review article. The activity of a dopaminergic neuron (its instantaneous firing rate) is one of the main determinants of how much dopamine is released per unit time at its many synaptic terminals. The amount of dopamine synthesized is also ...


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I've mostly figured it out now, and I've a better idea of the words and phrases I need to search to get the information I was asking for. The short answer comes from wikipedia: "The neurons' somata produce the enzymes that synthesize dopamine, and they are then transmitted via the projecting axons to their synaptic destinations, where most of the dopamine ...


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My short answer would be that there is no clear relationship between these two models about how visual information processing works in the brain. However, the terminology and evidence overlaps considerably which makes this confusing. One way to think about this is that the two models are explaining different stages of processing. The two visual streams is ...


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Psychophysical experiments have shown that during a saccade, attention is aimed at the target location. Instructing the subject to make a saccade from location A to C, while focusing on another point B proved impossible. The authors conclude that: [A] saccade executed to a peripheral location in the visual field involves the orienting of attention ...


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Short answer Females are more sensitive to some, but not all somatosensory stimuli. Males are either less sensitive, or as sensitive as females. Background A normative study by Blankenburg et al. (2010) determined reference values for a battery of somatosensory tests including cold detection threshold (CDT); warm detection threshold (WDT); thermal sensory ...


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The standard textbook neuron receives input at its dendritic tree, fires action potentials and has a single, long output axon to send the message off to distant locations. However, non-spiking, anaxonic neurons are not a rarity; in various sensory systems there are bipolar cells present that lack a clearly defined axon and are non-spiking, such as the ...


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The corpus callosum is the largest of the commissural neural pathways, linking the cerebral cortex of the left and right hemisphere. The sectioning of this tract is called a corpus callosotomy, which disconnects the two sides of the neocortex. A callosotomy is used in cases of intractable epilepsy, i.e., epilepsy that cannot be treated sufficiently with ...



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