Questions tagged [neuroanatomy]

Study of the anatomy and organization of the nervous system.

0
votes
0answers
17 views

What trajectory do action potentials take, from initial visual stimulus all the way to motor function?

Say we see a mosquito, and our brain tells us 'hey that's a mosquito, you should kill it.' Then we move our hands and slap/clap it. The initial visual stimulus is translated to an action potential ...
0
votes
0answers
17 views

What is the outer boundary of oligodendrocyte myelination?

The sensory and motor neurons comprising the spinal cord and brain stem have the interesting property that different structural components belonging to the same neuron can occupy both the PNS and CNS. ...
0
votes
0answers
25 views

Why different people have different Sympathetic reaction

We all know that sympathetic mechanism is similiar in humans . Why people react differently for example one may ran after seeing a lion while other may keep standing or may shout without escaping ?
0
votes
0answers
30 views

What is the need of dural venous sinuses?

I understand that the venous blood from the brain drains into the dural venous sinuses (which further drains into external jugular vein). My question here is that, why don't the veins from different ...
1
vote
1answer
77 views

Why are the grey matter structures of the inferior medial frontal lobe not directly (not via white matter) connected?

I have recently been trying to understand the three dimensional nature of the brain for a neuroanatomy class. Part of this strategy has included learning about structures such as the falx cerebri, ...
0
votes
0answers
24 views

What cell types comprise the median eminence and the tuber cinereum?

I have tried pretty hard to get a detailed description of what exactly the median eminence and the tuber cinereum are but to no avail. I am very familiar with their anatomical relationships (spatially)...
0
votes
1answer
92 views

What neurons' projections comprise the olfactory nerve (Cranial Nerve 1)?

Recently, I have been learning about olfaction. To my surprise, I am having a heck of a time finding explicit information regarding which neurons' axons are comprising the olfactory nerve. I am aware ...
0
votes
1answer
187 views

What are the brain structures directly on top of the brain stem?

I have been trying to learn the anatomy of the brain, and some information on their functions, through an iPad app called 3D Brain. Whilst going through the different parts, I have noticed that one ...
1
vote
1answer
2k views

What's the difference between the neuroendocrine system vs endocrine system?

This is what I have understood so far: Neuroendocrine system involved neuroendocrine cells (also known as neurosecretory cells) that receive nerve impulses by a sensory neuron to release ...
0
votes
1answer
27 views

Neurons and nerves [duplicate]

What is a nerve compared to a neuron? Is it a collection of axons alone or does it include cell body too? I'm pretty confused of what actually the "nerve" is composed of. I had imagined that the nerve ...
1
vote
1answer
62 views

Why are spinal nerves considered a part of PNS while the spinal cord is a part of CNS?

So from my common understanding, CNS consists of brain and spinal cord, and PNS consists of everything else. But the spinal nerves - the nerves connected to the spinal cord - why are those considered ...
2
votes
1answer
105 views

Are there any organisms, extant or extinct, that have only one neuron?

Nervous systems are useful in one way because they allow for integration of complex information. They are also useful because they transmit information very rapidly, over a large distance. However, ...
6
votes
1answer
299 views

Can turkeys run around when their head is cut off like chickens do?

Chickens may run around after their head is cut off if the head is severed near the base of the skull leaving the brain stem intact and missing the jugular vein. This usually only lasts for a few ...
1
vote
2answers
159 views

What makes the electrical charge inside the neuron more positive at the end of action potential and returns it to resting potential?

When a neuron's stimulated by something, electric potential difference changes immediately and inside of the neuron, becomes more potentially positive than the outside of it. I've read that sodium-...
0
votes
1answer
153 views

What happens in a brain of a person suffering with apathy?

According to this article Apathy is a profound loss of motivation not attributed to decreased level of consciousness, cognitive impairment, or emotional distress. Apathy refers to a set of ...
1
vote
0answers
16 views

VC06 neuron of c.elegans

My understanding was that all neurons and their synapses of worm c.elegans are already listed. As source of this map I'm using following databases (both should contain same information): ...
5
votes
2answers
620 views

Neuron connectivity- how are they connected physically

If Neurons are only connected through synapse and there is no physical connection, how are they just suspended in brain layers?
4
votes
1answer
294 views

Why is the hippocampus considered to be a cortical structure but not the amygdala?

I'm having some trouble understanding the anatomical differences that classify the hippocampus as a cortical structure but not the amygdala. I have included the screenshot of a diagram from Gray's ...
3
votes
1answer
107 views

What parts of the visual system could be responsible for a fixed, monocular scotoma?

Light enters the cornea, crosses the lens, hits the retina. Electric sinal travels from retina through the optic nerve, reaches the chiasma, crosses and makes its way to the visual cortex. My ...
0
votes
1answer
42 views

How does a neuron know to which one of the next neurons to pass the signal

Looking into how neural networks are build in the brain, here are a couple of facts followed by some questions: The neuron receives the signal through its dendrites and passes it to the terminal at ...
0
votes
0answers
19 views

Any volumetric data for areas of the brain?

I was trying to write an overview of AI and wanted to quantify some numerical data about the brain. It is easy to find many sources quoting 100 billion neurons. However, I would like to get the ...
2
votes
1answer
378 views

Why are the posterior and anterior inferior temporal cortex called area TEO and area TE respectively?

I don't understand why you would call them that. How did these names originate/where did these names come from?
6
votes
1answer
85 views

Are there any known rules that neurons always follow while transmitting/receiving signals?

I'm new to neurobiology so I don't know much about it. However, I have worked on artificial neural networks. Man-made AI networks all follow a handful of simple rules. I was wondering if biological ...
4
votes
1answer
293 views

Is olfactory input processed by the thalamus?

Is olfactory input processed by the thalamus? I know olfaction is the only sense that can bypass the thalamus, but are there cases where the input can project to the thalamus?
2
votes
1answer
56 views

Is there human Anatomy software that provides great detail?

Is there Anatomy software that is exact representation of human body, like let's say virtual reality tour inside human body from head to foot, detailing all organs even small, covering all systems, ...
5
votes
1answer
552 views

Why ambidextrous persons are so rare?

According to this article, only about 1% of all humans are ambidextrous: About 90 percent of people are right-handed, says Corballis. The remaining 10 percent are either left-handed or some ...
1
vote
1answer
56 views

Why are there exactly 207 morpho-electrical types of neurons?

I'm taking an introductory neuroscience course online, and it mentions that of the 55 morphological types and the 11 electrical types, there are 207 morpho-electrical types. How does this work? 55 ...
2
votes
1answer
546 views

What gives nerves their silver colour?

I always thought the silver colour specific to nerves was due to the myelin sheaths, but I've observed that unmyelinated C fibres display that same silvery appearance. Where does this colour come from?...
0
votes
1answer
36 views

What is the difference between an alpha subunit and a non-alpha subunit in ACh receptors?

When reading about ACh receptors, it is frequently the case that a protein is described as (alpha) or (non-alpha). However, I haven't really been able to find out what that means. What is the ...
1
vote
1answer
125 views

How fast the brain recover itself at sleep? What can be done to accelerate this process?

In Computer Science we have "Big O Notation" to describe how efficient is an algorithm at processing some task. Those can be linear, time constant, exponential among others. Using that analogy, How ...
4
votes
1answer
695 views

Are centrioles really absent in human neurons?

A booklet (issued by my school) claims, Centrioles, formerly believed to be absent in neurons, have been described in neurons and may be associated with the production and maintenance of neuro(...
1
vote
1answer
537 views

Where are action potentials initially created?

Is the axon hillock still the place where one thinks and talks of that action potentials are initially created? (I've heard this place moved into the direction of the axon initial segment.) If one ...
1
vote
0answers
120 views

An introduction to nuclei in the pons?

I have a couple of questions regarding the nuclei in the pons, thus I figured it would be best to frame the main question in the way that I did. My main question, however, is whether the basal ...
1
vote
0answers
102 views

How are the axons in the white matter bundled?

I wonder if the following question concerning the axons in the white matter does make sense. It is common knowledge that white matter is "composed mainly of bundles of myelinated axons" resp. is "...
2
votes
1answer
284 views

Where does the initial action potential come from?

When talking about action potentials we say that previous neurons caused an action potential in this neuron and that this neuron's action potential caused the same in further neurons. But what is the ...
0
votes
1answer
339 views

Why are the neurites from hair cells to spiral ganglion cells called axons?

In Kandel's Principles of Neural Science I found the following figure which shows the innervation of the organ of Corti: From the legend to this figure (30-10, p. 602): "The great majority of ...
0
votes
0answers
312 views

Distribution of the number of synapses per neuron

There is a mean number of synapses per neuron in the human brain which is not very well known, but is of order 10,000. (Some say, it's about 6,000, other say it's about 50,000.) What is known about ...
2
votes
1answer
129 views

Are intracortical axon branches myelinated?

I found the following pictures of axon trees: source source (axons are red) but didn't find a concise answer to the following question: Is it possibly true that the intracortical axon branches (...
1
vote
1answer
135 views

Are there axon branches that go up to cortex layer 1 and spread there?

I found the following pictures of axon trees: source source (axons are red) but didn't find a concise answer to the following question: Are there axon branches that go up to cortex layer 1 and ...
0
votes
0answers
109 views

How many synapses are there in the different target regions of a typical cortical pyramidal cell?

I found the following pictures of axon trees: source source (axons are red) but didn't find a concise answer to the following question: How many (in relative terms) branches terminate and how ...
0
votes
0answers
41 views

How many end segments does the axon of a typical cortical pyramidal cell have?

I tried to do some research - starting with a Google search for "typical axonal trees" - and found the following pictures: source source (axons are red) but didn't find a concise answer to this and ...
3
votes
0answers
45 views

Question About the Physiology of Seizures

Absence seizures usually occur in children between ages 4 to 14 (Hopkins Hospital). Spontaneous remission occurs in 65–70% of patients during adolescence (Medicine Central). My question is what ...
1
vote
0answers
106 views

What does synapses hold together?

From three answers to the same question at Quora I've learned of three forces that keep synapses together: They are held together by cell adhesion molecules (e.g. neurexin and neuroligin). They are ...
0
votes
1answer
20 views

Do corresponding areas in the two hemispheres arise from the same stem cells?

After having asked this question about the connectivity between clonal cortical neurons, I'd like to know: Do corresponding areas in the two hemispheres arise mainly from the same stem cells, ...
0
votes
1answer
90 views

Cortico-cortical connections

I wonder what the principal ways of (direct) cortico-cortical connections are. I came up with the following possibilities: vertical: a cortical neuron connects to another one in roughly the same ...
0
votes
0answers
149 views

Evolutionary advantages of gyri

Sulci and gyri are complementary views on the very same brain-anatomical phenomenon (Note that there is the named concept of gyrification, but not of sulcification, but it's the very same process.) ...
1
vote
0answers
47 views

If we had children wear an apparatus swapping e.g. Red and Blue colors, would their perception adapt?

In the context of neuroscience and philosophy, one difficult question is what makes colors so peculiar and vivid if they're just signals encoding light intensity coming from certain receptors -- an ...
3
votes
0answers
37 views

Spatial distribution of axons connecting distant groups of neurons

It would help me to shape my picture of the brain, if I knew the following: Consider two specified groups of neurons A and B in the brain that are well-located but quite distant from each other (e.g. ...
3
votes
0answers
203 views

Development of the commissural fibers

Having a look at the corpus callosum one sees that the axons passing the corpus callosum (the commissural fibers) connect mirror-symmetric counter regions of the cortex (roughly). Is there a model ...
0
votes
1answer
48 views

Homogeneous and complex nuclei

In the Wikipedia article on nuclei one reads: "The neurons in one nucleus usually have roughly similar connections and functions." I read this as "a nucleus usually is roughly homogenous", i.e. ...