Study of the anatomy and organization of the nervous system.

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1answer
4k views

Why is the brain white?

I have read many articles about how the brain is the most power-hungry organ in any living complex organism, requiring about 70% of it's oxygen supplies in the resting state. Since the usual medium ...
24
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4answers
2k views

How and where, in the human brain, are memories stored?

Background I am a computer programmer who is fascinated by artificial intelligence and artificial neural networks, and I am becoming more curious about how biological neural networks work. Context &...
19
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1answer
536 views

Why does regular exercise increase brain volume?

It has been shown in several studies that regular aerobic exercise increases brain volume in aging humans. The changes were observed in hippocampus and were correlated with dramatic reduction of age-...
11
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1answer
258 views

Do taller people have larger somatosensory cortices than short people?

When we assume that peripheral touch receptor densities are equal in tall and short people, then tall people should have more touch receptors than short people, given the larger amount of skin surface ...
10
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1answer
831 views

Where is the aneurysm in this picture?

I'm a curious person, I've never had any medical training, but I wish to know some more about aneurysms. Aneurysms are basically weakened spots in the elastic artery wall. This can eventually result ...
10
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1answer
434 views

Foveal ganglion cell density (Tay-Sachs Disease)

I’m currently reading on Tay-Sachs disease and have stumbled upon something regarding the typical “cherry red” macula symptom. On the one hand it is mentioned that the macula is almost devoid of ...
10
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1answer
144 views

Unilateral damage to vagus nerve

Context: The vagus nerves supply the neck viscera, heart, lungs and gastrointestinal tract. They join around the oesophagus to form the oesophageal plexus. Question: Would damage to one vagus nerve ...
9
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3answers
906 views

Do memories have mass?

If it were possible to live forever, would our brains grow infinitely with the number of memories that we store? Or would we remove old memories as we create new ones?
8
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4answers
1k views

Is there any way a human could whistle and be unable to speak?

Is there any situation anatomically, where a human could understand the speech of others perfectly, without any capabilities of speech themselves, but would retain the ability to whistle with a tune? ...
8
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1answer
226 views

How are bones growing, if bones are not connected to the brain?

If the bones are not connected to the brain, how is their growth controlled? This question is not a duplicate of the question Mechanisms of bone growth, as this question deals with how bone growth is ...
7
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1answer
657 views

Why do humans alone have the capability to have religious/spiritual experiences?

What is it in our brain that makes having such experiences possible? I assume other species don't have these. Sure there are instances in the natural world where you can see individuals of the species ...
7
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3answers
346 views

What exactly is Tinnitus?

What exactly is tinnitus? What is it's cause, and why do some people hear it and others don't?
7
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4answers
377 views

Why has evolution made neurons use spiking?

I'm going to be forward and say that I'm not a biologist. I don't claim to fully understand the functionality of a neuron from an electrical/chemical perspective... I'm curiously gazing from the ...
7
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1answer
1k views

How do neurons form new connections in brain plasticity?

I've been reading about brain plasticity and how the brain can "rewire" itself. One of the things that is not clear to me - how neurons can establish new connections. Does this rewiring mean that ...
7
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1answer
7k views

What are the advantages and disadvantages of being ambidextrous?

Most of us have one dominant hand. We find it nigh on impossible to do very delicate or dextrous activities with our other-hand. This seems like an apparent weakness, and a rather odd one when you ...
7
votes
1answer
388 views

Are cerebellar basket and stellate neurons actually different cell types?

The title more or less says it all, but to contextualise a bit: Cerebellar molecular layer interneurons have been classified, probably since Cajal, into the basket cells, which synapse onto the soma ...
7
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1answer
109 views

Neuronal coordinates of C.elegans

Is there a list of neural coordinates for C.elegans? I need it to build a 3D model. Update: What is available at the moment is: full connectome for example, at openconnectome; neuron description ...
7
votes
1answer
560 views

Is the six-layer cortex model of the mammalian cortex still the most accepted model?

I've been reading a bit about the different layers of the cerebral cortex and its clear that certainly not every region of the cortex has the same number of layers. Thus, the idea that every region ...
7
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1answer
182 views

Disproportion in cranial nerve innervation?

The cranial nerve innervation is highly disproportionate, as far as humans are concerned. I am not sure of the advantage of being innervated by cranial nerve versus being innervated by a normal ...
6
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2answers
370 views

Why can't our eyes smoothly transition from side to side without focusing on a moving object?

Why are we not able to slowly and smoothly look from side to side, or up and down in a single and smooth transition, given that we are able to do this if our eyes are focused on a moving object?
6
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2answers
1k views

Density of neurons/cells in the mouse brain

Could someone point out some relevant papers or resources (an online DB maybe?) describing the density of neurons (or, more in general, of cells) in different areas of the mouse brain?
6
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3answers
136 views

Hebbian theory “fire together” clarification

Donald Hebb states it as follows: "Let us assume that the persistence or repetition of a reverberatory activity (or "trace") tends to induce lasting cellular changes that add to its stability.… ...
6
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2answers
233 views

Are there nerves in the umbilical cord?

I have always imagined that cutting the umbilical cord after birth might be painful. But I have always been confused about who would feel the pain and why. It occurred to me that the mother or the ...
6
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1answer
75 views

on/off behavior of neural networks

What causes a group of disembodied neurons in a dish to fire after a silence? If there are no neurons providing a stimulus for more firing (as in a dish of disembodied rat neurons), then why don't ...
6
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1answer
298 views

Which organisms have the neuroanatomy Roger Penrose supposes play a role in consciousness?

In The Road to Reality, Roger Penrose suggests that certain brain structures might play a role in consciousness Most particularly, lattice neuronal microtubules, as originally suggested by ...
6
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1answer
173 views

Do people with congenital analgesia feel cold?

There are a few diseases that cause an insensitivity to pain. This question asks about the relationship between the cold and pain, which got me thinking: Is shivering a response driven by the ...
6
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1answer
186 views

Long term effects of “brain freeze” on the cerebral vasculature

According to one theory, ice cream headaches are caused by an increase in blood volume of the anterior cerebral artery: Another theory into the cause of ice-cream headaches is explained by ...
6
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2answers
307 views

Why do the brains of cocaine-users shrink faster than the brains of non-cocaine users?

http://news.sciencemag.org/sciencenow/2012/04/cocaine-may-age-the-brain.html?rss=1 Cocaine-dependent individuals showed a significantly greater-than-normal age-related decline in gray matter in ...
5
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1answer
210 views

Neuroscience of mathematicians

I've tried to google this but everything that comes up are things like "mathematical neuroscience" rather than the other way around. Specifically, I'm interested in the workings of a mathematician's ...
4
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2answers
137 views

Headshot = instant kill? [closed]

While whatching a film, I've been thinking about how does a headshot kill someone, and how long does it take? For example let's say you've beeing shot by a normal (police) handfired weapon - no ...
4
votes
3answers
461 views

What exactly is the neural receptive field?

Neural receptive fields map the spatial or temporal distribution of the data to individual neuron excitation, if I understand correctly, but I do not understand if receptive fields (especially in the ...
4
votes
1answer
82 views

What (open) software there are for simulating behaviour of human (cortical) neurons?

Is there any reliable open-source software for simulating the behaviour of human cortical neurons? I am looking for serious software, so let's assume I have access to a computer with more than 10,000 ...
4
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2answers
444 views

Extraretinal photoreception in mammals? [duplicate]

A Finnish firm Valkee sells light-ear-plugs against thing such as jetlag. I asked a researcher in Aalto university how do they really work and he responded ...
4
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2answers
409 views

Does learning increase the number of neurons in the brain?

I am attempting to understand neurogenesis related to learning. Does learning increase the number of neurons in the human brain? What would be some good scientific publications to read?
4
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2answers
308 views

What is the relationship between W, X, Y and P, M retinal ganglion cells?

In Guyton and Hall Textbook of Medical Physiology (12e) the retinal ganglion cells (RGCs) are classified into W, X, and Y types. However, in Gray's Anatomy (40th ed.), RGS are subdivided into midget ...
4
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1answer
65 views

Do local field potentials (LFP) create waves on the surfaces of nerve cells?

Are waves created by the LFP on the surfaces of neurons cell bodies? Since the cells have a resting potential, do these waves create harmonic oscillation of the membranes at particular frequencies? ...
4
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0answers
337 views

How do duplicate brain regions (ex: left/right amygdaloid body) operate together?

I frequently hear talk about parts of the brain like "Amygdala" or "Hypothalamus", so I looked them up in an app called "essential anatomy". What I see is that there's mirror symmetry, and most of ...
3
votes
1answer
1k views

Why is the pituitary gland located in the brain?

Why is the pituitary gland located in the brain in humans, instead of elsewhere in the body? Why would this be an evolutionary beneficial adaptation?
3
votes
1answer
726 views

Neurons with thousands of connections: where are the extra connections coming from?

If every neuron has only one Axon but can can have thousands of (or let's say, even just ten) incoming Axon connections via its dendrites, where are the extra connections coming from? It seems to ...
3
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3answers
298 views

Mechanical cause of loss of consciousness

Consciousness is an electrical and chemical interaction in the brain, caused by neurons firing and chemical interactions. How does a mechanical "force" cause this to stop working? i.e. How does a ...
3
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1answer
153 views

Can the dendrites of sensory neurons be a meter long?

The typical textbook structure of neurons is a cell with a short dendritic tree and a long axon. The dendrites receive information and send it to the axon via the cell body (soma). The axon is a long ...
3
votes
1answer
37 views

Do axon grows after cutting/damaging of some of its part?

Do axon grows after cutting of some of its part to near original place? Do axon restores after local damaging of some of its part? I take https://class.coursera.org/neurobio-001/ classes and learn ...
3
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1answer
122 views

Specific location where nerves converge

I'm looking for the "earliest" specific site where the 3 following nerves' sensory signals "converge": Trigeminal nerve Median nerve Superficial peroneal nerve By "earliest", I really mean the ...
3
votes
1answer
96 views

What is the advantage to neurons being asymmetrical?

Does having a central axon and dendrites result in any advantage compared to if the neuron was symmetrical?
3
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1answer
566 views

Can the sensory neuron network and the motor neuron network be considered separate networks?

I am reading up on the nervous system using wikipedia and trying to interpret one infographic on this page: I've always thought of the human nervous system as a singular network of neurons. This ...
3
votes
1answer
162 views

What in neurons and their connections changes during the process of learning?

I'm not sure if this question belongs more in physics or biology (or maybe even computer science)... but biology seemed to fit more. What changes in the state of our brains when we learn things? ...
3
votes
1answer
94 views

What is the role of the tissue surrounding neurons in decision making and taking control of impulses?

How does the fatty tissue surrounding neurons supports and enhances the speed of electrical impulses? How does it stabilize connections that take control of impulses and decision-making? The cells ...
3
votes
1answer
49 views

Can an upper forearm amputee correctly control the Median and Ulnar nerves

I'm an engineer who is looking to build a robotic hand for people without their upper forearm(from center of forearm in direction of hand), controlled by the Thalmic Myo(an EMG sensor). I am first ...
3
votes
1answer
147 views

What are cranial nerve nuclei?

I am having a really hard time trying to understand what cranial nerve nuclei are. I have been reading/watching videos and I keep hearing, "that is where the cranial nerves make connection with the ...
3
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0answers
20 views

Evolutionary motivation behind number of neurons in DCMMP

I'm studying neuro-anatomy right now and I was surprised to learn that there are only three neurons along the Dorsal Column Medial Lemniscal Pathway (DMLP) which relays mechanical sensations from the ...