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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 ...


8

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

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

I'll tackle this question from a functional point of view. Gray matter are cell bodies, white matter are myelinated fiber tracts. In the brain, the gray matter is basically the cortex, the white matter lies mainly underneath it. The Cortex is the place where all the higher mental processing takes place (Fig. 1). Fig. 1. Cortical functions. Source: Penn ...


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 ...


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

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

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

20 Watts. Watson mentioned this in 2011: "The human brain only requires 20 watts of power to operate ... Watson? About 20,000 watts." An interview with John Kelly (an IBM senior vice president and director of IBM Research) also puts the brain at "about 20 watts" (but puts the machine at 85 kW; the inconsistency doesn't matter for this question). Popular ...


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

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 ...


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 ...


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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

It is generally accepted that all activity having to do with conscious experience is mediated by spiking in the cortex. Sub-threshold activity, such as excitatory postsynaptic potentials (EPSPs) are not carried forward in the nervous system and will 'fade' before having an effect. It all revolves around action potentials. Quoting from Kandel et al. (2000): ...


5

The superior colliculus can be regarded as the center of saccadic eye movement. It contains a topographically organized representation of the visual space in its upper layers, and saccade-related activity in its deeper layers (Van Gisbergen et al., 1987). Ablation of the superior colliculus unilaterally eliminates saccades contralateral to the lesion, and ...


5

Here's the only one that's easy to find in google scholar, but there might be more: Page, F., Coleman, G., & Conduit, R. (2006). The effect of transdermal nicotine patches on sleep and dreams. Physiology & Behavior, 88(4), 425-432.


5

I agree with much of AliceD's well-cited answer, but here are a few extras. What part of the brain is actively controlling saccadic movement? It is not clear how you would choose just one area of the brain, given that a whole network of cortical and sub-cortical areas are involved, and what you mean by "actively controlling". The superior ...


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

There is a good article on Wikipedia on the Neuroscience of Free Will, with far too much content to adequately summarize here. Since your question is focused on long-term prediction of behaviour, I'll just mention about that. Using newer fMRI technology, Soon et al (2008) used a learning algorithm to predict "free will" decisions from brain activity about ...


5

Gap junctions can couple cells directly electrically. Cell types electrically coupled via gap junctions include neurons, the pancreatic islets of Langerhans (Andreu et al, 1997) and cardiac cells (Fig. 1.). In contrast to chemical synapses, information transfer via electrical "synapses" (gap junctions) is nearly instantaneous. In chemical information flow, ...


4

When serotonin (5HT) uptake is inhibited, 5HT diffuses away from the synaptic cleft. It is believed that eventually 5HT disperses in the extracellular space and reaches the dendritic regions. The delayed action (say, 2 weeks) can be explained by 5HT's action on 5HT1A receptors in the dendritic region. After continuous activation of 5HT1A receptors, they ...


4

While model neurons like the leaky integrate and fire may use a simplification in which the neuron forgets all previous information when it emits a spike, in a biological neuron, the synapse and the soma are relatively electrically isolated from each other, so the voltage activity of the action potential does not make the synapse "forget" the EPSP. Although ...


4

Biondi et al. (1998) compared MR images of monozygotic twins and found that while the brains of monozygotic twins are not identical, they are similar. Relevant for understanding the concordance rate of schizophrenia in monozygotic twins, Suddath et al. (1990) examined MR images of monozygotic twins who where discordant for schizophrenia. They found that the ...


4

Part of what makes speech possible is a complex set of interactions between a number of different muscles that control aspects of producing speech sounds like airflow and mouth shape. Humans are unique in the complexity of the sounds that we can produce. Even if we granted the science-fiction that would be necessary to put a human brain into a chimpanzee and ...


4

You could start with Hochner's papers, like this one: Hochner, B., Shomrat, T., & Fiorito, G. (2006). The octopus: a model for a comparative analysis of the evolution of learning and memory mechanisms. The Biological Bulletin, 210(3), 308-317. http://www.biolbull.org/content/210/3/308.full As far as I know, he is a world expert.


4

Short answer A cap of magnets, or state-of-the-art TMS protocols, will not make you smarter. Background First off, TMS uses bursts of magnetic stimulation in the order of milliseconds (Rothkegel et al., 2010). Pulses of magnetic stimulation are used, because permanent magnetic fields will not induce current flow. Hence, wearing a cap of permanent magnets ...



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