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11

Short answer Yes, there is a difference between hearing and understanding sound. Background Acoustic information is processed in different neural centers along the auditory pathway. The auditory system runs from the peripheral end organ in the inner ear (the cochlea) to the cortex. Along the way various processing steps are carried out. For ...


11

Typically 'presynaptic' and 'postsynaptic' are used to indicate two neurons that are connected, as you indicate correctly in your second example. Information flow in the nervous system basically goes one way. If one neuron fires (presynaptic cell) it can chemically activate another cell on which it synapses, as shown in the following figure 1. As an ...


8

First of all, the human brain is distinctively larger than that of any other primate, mainly due to the great expansion of the cerebral cortex. The underlying structures have remained relatively stable (Toro et al., 2008). As the cortex overlies the rest of the brain, a solution had to be found, because the whole brain did not have to inflate to increase ...


7

Seizures induced by stroboscopic lights are an example of reflex seizures. This type of epilepsy includes seizures evoked by touch and movements as well. The mechanism behind generalized reflex seizures (generalized epilepsy, as opposed to partial epilepsies, is accompanied by a loss of consciousness) was abstracted nicely by Ferlazzo et al., 2005: ...


7

Part of the difficulty in studying time perception is that memory is known to be biased by numerous factors including arousal and salience. So while people commonly report time slowing down during specific events, it is difficult to differentiate the effects of retroactive memory bias in encoding and recall from actual increased resolution in the perception ...


7

My knowledge of the neurobiology of pleasure (aka, hedonia, hedonic happiness, happiness, "liking", reward, etc.) is admittedly lacking, but I'd contend that this is mostly true because we actually know very little about how pleasure is instantiated in the brain. So the answer to your question is that we don't know! First of all, mesolimbic dopamine seems ...


7

This will be a long post. FYI. To my knowledge, there is no evidence for back propagation in the brain. If you're interested specifically in that topic, Geoffrey Hinton (Dept. of CS @ UofT) has written about it. I'll try to focus on the biology. Some basic neurophysiology first. Neurons have a slightly negative electrical resting potential ...


7

They are ordered based on when they were discovered/named (as pointed about by Ana's comment). Alpha and beta waves were among the first signals observed in EEG data. From Wikipedia: Alpha waves were discovered by German neurologist Hans Berger, most famous for his invention of the EEG. Alpha waves were among the first waves documented by Berger, along ...


6

There are quite a few stations between cochlea and the brain and I will focus on the auditory nerve. That said, your theories (a) and (b) are both correct, and therefore (d) applies as well. (a) Neurons in the auditory nerve increase their firing rate when sound level is increased (Heil et al, 2011). This can be regarded as the primary mechanism for ...


6

Short answer Yes, continuous exposure to white noise affects neural responses in the auditory system. First, it can alter the tonotopic map in the auditory cortex. Second, it can lead to reduced responsiveness of the auditory thalamus. Background Note: this answer is based on animal experiments using extreme conditions, namely a continuous noise ...


6

Short answer Damage to the inner ear can result in an asymmetric distortion in pitch perception between the two ears. This phenomenon can result in the same tone being perceived as a different pitch by the two ears. Background Damage to the inner ear (the cochlea) can lead to hearing loss. Hearing loss can sometimes lead to changes in perceived pitch. For ...


6

The corpus callosum is a massive horizontal white matter tract (commissure) that connects the two hemispheres and it is considered the most important route of communication between the hemispheres. However, there are five additional commissures that cross the midline, namely: Anterior commissure, connecting the two olfactory bulbs and the temporal ...


6

Generally spoken, synesthesia is unidirectional. For example, grapheme–color synesthesia (i.e., letter–color and digit–color synesthesia) is the most prevalent type of synesthesia. The presentation of a grapheme leads to an additional synesthetic color percept. Although grapheme–color synesthetes are strongly influenced by the synesthetic color perception ...


6

Interesting question! I performed a fairly extensive search in Google Scholar and Scopus using various keyword searches, including, but not limited to "color blindness and plasticity", "color blind and brain", "dichromates brain", and "monochromates brain". Strikingly, I found nothing. The reason is aptly explained by Solomon & Rosa, 2014 and I quote ...


6

From my undergraduate biology degree, I am only familiar with the second use of the terms which you describe. That is, the terms pre-synaptic and post-synaptic describe a spatial relationship to the synapse, which has directionality, as you know. If the terms are used to describe whole cells, as Chris Stronks covers, and as people often do when describing a ...


6

Visual acuity is highest in the foveal region, namely around 1/60 of a degree, or 1 minute of arc (1 MAR). At about 30 degrees of eccentricity, visual acuity is reduced to anywhere between 1.5 and 10 MAR when determined by a shape recognition task, as shown in Fig. 1 taken from Lie, 1980: A later study (Anderson et al., 1991) shows the following picture: ...


6

I will try to answer all of your main and sub questions structurally below: How do neurotransmitters manage to depolarize the inside of the cell? Do they force the cell to give up pumping out Na ions? No, the Na,K-ATPase (the sodium potassium pump) keeps active, also during the action potential (AP). Do the neurotransmitters themselves contain ...


6

It is well documented that people are able to selectively attend to different speakers. The ability to tune-in to a particular speaker and filter out others was dubbed the cocktail party effect, since it is the kind of skill that is required in when trying to have a conversation with another person in a crowded party. A common way of studying this ...


6

Psychophysiology is totally outside of my wheelhouse, but here it goes… Those feelings in your chest, face, arms, etc. aren't an illusion. Indeed, it's long been argued that physiological arousal (in your body) is a core component of emotional experience (e.g., James, 1884; Russell, 1980)--alongside feelings of pleasure and displeasure. Moreover, that ...


5

There is data on this question generated by research on the embodiment of spatial cognition. The idea here is that we mentally represent and construct space in relation to our bodies. From this perspective, the differences that you describe (left vs. right more complicated than up vs down) stem from the properties of how we perceive the world in our bodies: ...


5

The short answer is we don't know for sure. Look up "alexia" and "agraphia"; pinpointing the regions of the brain that, if damaged, interfere with reading might give some indication of the cortical regions involved. Visual cortex (back of the brain) is obviously necessary for the general population, but it's clearly possible for blind people to learn to ...


5

I think the major reason is inertia, in the sense that many labs use Matlab, so many Matlab toolboxes are available, so many labs train people in the use of Matlab... However, as a trained software engineer turned Neuroscientist who has been programming in various languages for close to 30 years, there are several reasons why I actually enjoy using Matlab. ...


5

Nature Neuroscience offers such a possibility. http://www.nature.com/news/nature-journals-offer-double-blind-review-1.16931 See also Does anyone know of any clinical psychology journals that use a double-blind review process?


5

Short answer Neurons can increase or decrease the amplitude of their response. A neuron's response strength can be regulated by adjustment of the cell-surface expression of excitatory receptors. Background First off, this question is very broad. To narrow it down I will focus on learning processes in the hippocampus involving long-term potentiation (LTP). ...


5

I think you should reverse your approach. Rather than trying to find every prerequisite, start reading sections of PNS and as you encounter something you don't understand, look up the background information. It's an exhaustive work (and well worth reading!) but you're going to find different sections require different levels of background. For example, ...


5

The question that you are referring to is worded in a way that I think is leading to the confusion. The question in the title is "Can the mind affect the brain?" but in the question body the final question posed is "Does [a thought producing a tear] not contradict the (physical) law of cause and effect?". The answer is yes to the title question: the mind ...


5

There are other meanings of "potential" than the regular meaning "having or showing the capacity to become or develop into something in the future" (source: Google Translate). In case of "resting potential" it refers to the voltage difference across the cellular membrane. Every cell maintains a voltage difference across the membrane (see a related question ...


5

You are right to suspect that cognitive control and executive function are essentially interchangeable, at least for most purposes. Among researchers in the area, I would say there is a slight difference, however. Cognitive control refers to the more abstract concept and affords researchers more degrees of freedom in defining what that means operationally ...


5

You are right that active adult neurogenesis is generally considered to be restricted to the dentate gyrus of the hippocampus, and the subventricular zone of the lateral ventricles. The latter generates neurons that subsequently migrate through the rostral migratory stream to the olfactory bulb to become interneurons (Ming & Song, 2011). Although the ...



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