Hot answers tagged neurobiology
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Yes! Recent work using fMRI has shown that subjects can indeed control localized brain regions through practice [1]. Some regions that have been tested include the rostal ACC [2] responsible for pain perception, PPA responsible for representing locations, and FFA responsible for representing faces. Repeated experiments seem to suggest the phenomenon is ...
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One relatively recent review on this topic is Rushton & Ankney (2009). They report that there have been a large number of studies with varying results:
28 studies, covering a total of 1,389 subjects, used brain imaging techniques to estimate the size of the brain. Correlations with general mental ability (GMA) ranged from 0.04 to 0.69, with an ...
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It is not meaningful to talk about your brain processing something as 'right-side up"' or 'upside-down'. The 'images' in your brain are just collections of neural activations, and not actual pictures. Thus they cannot have an orientation. The only meaningful way to test your question is to try flipping the input the brain receives and seeing if it can cope.
...
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If by continuity you mean, "a feeling that I am who I was before the operation, (perhaps with some changes)", then it seems that each hemisphere would separately maintain continuity, in the same way patients after massive strokes and other sudden brain injuries don't usually feel "they are a different person".
Research by Turk et al. (2003) suggests it's ...
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When performing certain tasks, people’s inferences approximate Bayesian inference to a remarkable degree. For example, when people receive both haptic and visual information about the size of an object, they combine this information in a manner that very closely resembles Bayesian inference, taking account of the uncertainties associated with the visual and ...
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Caenorhabditis elegans is probably not an ancestor to Humans. As found in Sponge proteins are more similar to those of Homo sapiens than to Caenorhabditis elegans, certain sponges were found to have more similar protein structures to humans than C. elegans suggesting the sponges are the ancestor.
For your second point, it depends what you mean. The actual, ...
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I think part of the answer to your question is going to include the dopamine "reward" pathway in the basal ganglia. In particular, a leading theory of dopaminergic function is the predictive reward error or reinforcement learning hypothesis. In this theory, dopamine neurons signal expectations about the outcome of particular stimuli.
Some key experiments ...
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There are some important relationships between the c. elegans nervous system and the human nervous system that should be pointed out here:
Neurons in both animals communicate with each other via synapses that use special molecules called neurotransmitters to convey activity. All major neurotransmitters used in humans are also used in c. elegans ...
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Modern homunculus arguments don't assert that there is physically a little man in your head. This would be a completely vacuous argument, and nobody would make it in the present day. When people make the homunculus fallacy today, they usually do it in the same fashion as you do: all the sensory information is assembled 'somewhere' and then 'some brain ...
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I think you are succumbing to the homunculus argument, the fallacy that there is some sort of image in the brain for someone to view. There is no magical theater in your head where what is incident on your retina is projected. All you have in your brain is complicated patterns of neural activity, there are no images and nothing to view. However, these ...
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There is a huge body of literature on axon growth cone guidance which will give you some insights into how the biology works. Unfortunately, incorporating it all into a model is probably going to make it unwieldy unless your express purpose is to model the physiology, which doesn't seem like the case.
Here are some references:
Hong K, Nishiyama M. ...
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With whales in particular, they don't even have arms or legs, so I wouldn't expect them to have large regions of the brain devoted to, say, fine-motor skills.
Ah, but they also have a complete three dimensions to move in, unlike us humans who only have about 2.5 dimensions to move in. Also, they have a number of different "limbs": tail, multiple fins, ...
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The MTL consists of (note that some structures overlap):
cortical areas, which can be categorized in at least three ways:
portions of two gyri
entire parahippocampal gyrus
anterior medial side of fusiform gyrus
five named cortical areas:
perirhinal cortex
parahippocampal cortex (see parahippocampal gyrus)
entorhinal cortex
presubiculum*
parasubiculum*
...
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First - you might want to redefine you search. Are you looking for happiness or rather positive affect? Happiness is fairly ambigious term, and it's much more associated with positive psychology studies on well-being. If you are interested in more global definition of happiness, check the work of Mihaly Csikszentmihalyi.
On the other hand, there is a ...
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The Neurobiology and Genetics of Borderline Personality Disorder indicates that a good deal of research has been done but a specific mechanism causing it has not been pinned down. It appears to be largely genetic which would strongly suggest a neurobiological/nature basis as opposed to a "nurture" related cause.
(emphasis mine)
In summary, the ...
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It's a local rule. All that it means is that the connection between two neurons gets stronger if you use that specific connection more. The specific connection (the synapse) must be used though; it doesn't apply to two random neurons that aren't connected that happen to fire at the same time.
Hebbian learning is generic term for outcome; there are ...
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The interface between the brain and the hand is not like a USB computer port, and we don't unplug the biological arm and plug in a mechanical one instead. We implant electrodes to just a tiny fraction of the neurons in M1 (about a hundred, out of millions), and use their signals to control the mechanical arm.
So the answer is yes. The monkeys don't lose any ...
8
It likely depends on the cue presented; the study Memory and metamemory for songs: the relative effectiveness of titles, lyrics, and melodies as cues for each other found these interesting results for what portion of Melodies, Titles and Lyrics were correctly remembered vs cues that presented part of the melody or lyrics or the title of the song.
Some ...
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The fact that these people don't exhibit a lot of change in behavior, and report no real difference after the operation (other than in contrived tests) suggests that our idea of a single conscious "self" is simply wrong.
This sort of question is probably never going to be answered to anyone's satisfaction, any more than you could answer questions about what ...
8
Blood pressure decreases as one stands up.
A model of cerebral blood flow has been created in Modeling Cerebral Blood Flow Control During Posture
Change From Sitting to Standing:
The characteristic features are that after standing up for 60 s, the pressure (both systolic and diastolic values) drops significantly from a mean pressure of approximately 95 ...
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I think part of what makes this question confusing is the use of expressions like "what the eye sees", "what the brain sees" and "what the frog's eye tells the frog's brain". Nobody sees anything except the experiencing subject. When one stops thinking that the brain (or some visual-system part of the brain) observes the image on the retina, then the ...
8
If we stick them in an MRI, the activation will not be very fine-grained. There are roughly 630,000 neurons in a 3x3x3 mm voxel recorded during fMRI. However even this coarse detail is sufficient to perform many impressive mind-reading tasks (e.g. Mitchell et al., 2008)
But what if we were able to record every single neuron in the brain simultaneously, ...
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The major neural models of consciousness at the moment roughly fall into two camps: cognitive and phenomenological. They are defined by controversy surrounding what types of experience qualify as concious.
Cognitive models
On the one hand there are strong cognitive models of consciousness, such as the one proposed by Stanislas Dehaene, where consciousness ...
8
There are many neuroscientists who use the techniques of advanced mathematics and statistics to analyze actual neural data for patterns.
George Gerstein, who is now retired, has been a pioneer in applying "particle" methods in analyzing neuronal interactions. The originator of the Gravity transform, he used this tool to untangle some of the stochastic ...
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I'd like to add to Chuck's excellent answer; the computational approach is very well-represented in neuroscience, and actually involves a large number of very heterogeneous methods. Thus, a very different set of neuroscientists and examples have sprung to mind for me.
To my mind, the best single example of the utility of a computational approach to ...
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I'm glad you asked! The two fields are really quite different, but I think people get them confused since the terms both make reference to physics and something vaguely mental.
Psychophysics is basically the measurement of subjective percepts corresponding to physical stimuli (e.g. measuring pain thresholds or visual acuity). So here the 'physics' refers ...
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A minor addition to Jeff:
There are ongoing researchs on controlling brain's response (e.g amygdala) to negative situations and using this techniques for psychiatric interventions (e.g. for anxiety disorders, depression). [1]
There are different possibilities for learning adaptive coping strategies with simple, stuctured biofeedback training setups. But ...
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From an information processing perspective, I'd conjecture the following points:
Many songs have lyrics that are difficult to decipher. If you can't decipher the words, then you wont be able to recall them. If you decipher alternate words, then this may reduce the degree to which the words have semantic meaning, and therefore the ease with which the lyrics ...
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There are a few factors which confound an effort to find such an upper bound for grid size. Since these experiments normally require the rat to be attached to the recording apparatus to ensure the quality of the recorded data, the first obstacle would be perfecting the ability to record from the entorhinal cortex while the rat is untethered, through ...
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I was about to recommend The Oxford Handbook of Social Neuroscience, by Decety and Cacioppo (Oxford University Press, 2011) which has an entire part (10 chapters) dedicated to the neural basis of emotion regulation, motivation, and social interactions. However, I just noticed Panksepp's forthcoming book, The Archaeology of Mind: Neuroevolutionary Origins of ...
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