Questions tagged [neuroscience]
The study of the structure and function of the nervous system and its components.
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What are the factors affecting reaction time and/or reflex velocity?
So there was this video of a cat killing a snake: Cat reaction time
and another of a bobcat killing a rattlesnake Bobcat kills rattlesnake
And then this from wikipedia on sand cats:
In the Ténéré, a ...
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How can animals defecate or urinate in fear if the nervous system seems to opposes it?
How do animals defecate and/or urinate in fear even though their 'flight or fight' response seems to oppose it? I have seen many cats and dogs urinate and defecate when they experience extreme fear. ...
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Why does Sanjay Gupta's brain look so unusual? (brain model shown on CNN) The subdivisions don't look like the lobes I learned in school
above: Screenshot from CNN's May 18, 2023 Feinstein’s office confirms broader health complications, contradicting senator’s denial below: from anatomyinfo.com's Parts of the Brain
Neurosurgeon Dr. ...
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Stroke research question - has there been research in mirroring muscle electrical signals from a good limb to the bad one?
Transcutaneous electrical neural stimulation is an established tool to help stroke victims recover use of a paralyzed limb by engaging neuroplasticity. Has anyone here heard of research where you wear ...
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How does brain activity change when focusing on something within peripheral vision, as opposed to the fovea?
Normally when looking around, we mentally focus on what we see within our fovea, as that is where we have the greatest visual acuity. However, it is still possible to focus (both physically with the ...
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What determines the growth and destruction of neurons and neuron connections in the brain?
How does the human body determine what connections need to be formed between what neurons? I know that due to neural plasticity, neurons will be generated or destroyed. Hebbian learning talks about ...
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What are the key mechanisms of control and transport of ATP from mitochondria to synapse in active firing neurons?
I am working with a group in the field of neuronal activity (in computational neuroscience), in specific the firing rates at different ensemble/population hierarchies.
It is well established that ...
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Have elephants (or any species other than humans) been known to cover their dead?
I was just reading this blog on HarperCollins website about 5 animals that grieve. Of elephants, the following claim is made:
They bury their dead and pay tribute to the bodies and to the bones. [my ...
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Is colocalisation of a protein with a presynaptic marker sufficient evidence to say that the protein is a component of axon terminals?
I am reading journal papers about the subcellular localisation of the insulin receptor (IR) in neurons.
I have read a paper stating that IR is highly enriched at synapses, localising to both the ...
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What is accumulation and release centre of neurohormones?
What is accumulation and release centre of neurohormones?
Is it hypothalamus?
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Action Potential and Impulse Direction
My textbook describes generation of action potential due to an "induced increased membrane permeability to $Na$+ ions" and presents the ad hoc fact that electric current would flow from the ...
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Is there a quantitative report for cortical homunculus?
Almost all websites that I see for cortical homunculus only show the final picture with some qualitative descriptions such as "hands have more dexterity and occupy more motor cortex."
But is ...
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Which co-transmitters are released first?
I understand that a single neuron can release different neurotransmitters depending on the frequency of its stimulation (see https://www.ncbi.nlm.nih.gov/books/NBK10818/). As the frequency of ...
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Can acetylcholine leak away from the synapse and cause spasms?
I am currently studying Pharmacology and a question came to mind. We know that Acetylcholine is used as a neurotransmitter in the neuromuscular junction, both Sympathetic as Parasympathetic, but as I ...
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Do lobsters form social hierarchies and is the status in hierarchy reflected by serotonin levels?
In his book 12 rules for life Jordan Peterson claims that:
Consider serotonin, the chemical that governs posture and escape in the lobster. Low-
ranking lobsters produce comparatively low levels of ...
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Why is saltatory conduction in myelinated axons faster than continuous conduction in unmyelinated axons?
How does spacing apart sodium and potassium channels allow the action potential to travel faster down the axon? This is the reason always cited for saltatory conduction and myelination, but my mental ...
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What is the evidence for cognition being mainly confined to the brain?
We believe that the processes of cognition are mainly confined to the brain.
What is the evidence for that?
I understand that the brain shows increased oxygen saturation in fMRI scans while thinking ...
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Why chemical synapses are more common?
Reading into the types of synapses I found out that there are two types of them; electrical and chemical.
chemical synapses use neurotransmitters to transmit impulses, are slower than electrical ...
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Difference between spike and sub-threshold potential?
The Theoretical Neuroscience textbook by Peter Dayan has the following paragraph describing some intracellular recordings. I can't quite understand the statement about how spikes propagate down axons ...
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Are afterimages centrally regulated?
As I understand, negative afterimages might be induced by retinal cone bleaching or neuronal adaptation. I have heard that some experiments have suggested that afterimages can be centrally regulated. ...
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Why do we like music?
Music is, of course, just a sequence of sounds. Sounds are vibrations in the air, which our ears detect. So why do we find certain sequences of sounds to be appealing? What makes us want to hear these ...
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Can we change our dopamine baseline levels?
Can we change our dopamine baseline levels? High dopamine levels improve alertness, problem solving, but may also cause anxiety and aggression.
I've read that smiling and laughing, eating certain ...
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Causes of Misophonia
Whether it's snacking on chips, munching on salad, or simply chewing gum, when I hear someone do it within an earshot, it drives me completely bonkers!
It doesn't matter if it's my girlfriend, my ...
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Emotions in Animals Based on Neuroscience
I know very little about the subject, so please forgive any misunderstandings in the question. First of all, by emotion, I mean feelings of pleasure and suffering and not merely just sensory ...
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What happens if we lose voluntary control of our breathing?
Breathing can be controlled voluntarily, even though it is automatic. What happens if a person loses voluntary control of their breathing? How much would it effect day-to-day life? What are its ...
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electrotonic spread and screening
(In physics.stack I have been suggested to post my question also here.)
In the classical theory of passive neurons (where the action potential is not yet excited), the voltage is successfully ...
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NMDA receptor depolarization
I learnt that two factors for NMDA receptor channels opening are:
1)Binding of glutamate
2)Depolarization of postsynaptic cell (to remove the Mg+2 block)
Given that depolarization starts in axon ...
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Are two eyes necessary for 3D vision?
It has always been my understanding that humans have two eyes so that we can have 3D vision: the left eye sees more of the left side of an object than the right eye and vice versa. This helps us to ...
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Thoughts precede neuron firing or vise-verse?
I am at the verge of submitting a paper on 'scientific explanation of reality' to an international philosophy body. First submitted draft was returned by the evaluation expert, asking me to re-submit ...
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Do secretomotor neurons activate for secretory cells due to the absence or presence of water and electrolytes? Why?
I read this passage in a book called Integrative Action of the Autonomic Nervous System by Wilfrid Jänig. In this book, he states
Reflex pathways involved in the regulation of secretory cells and/or ...
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Where in the cochlea are frequencies below 200 Hz detected?
I understand that different frequencies are detected in different positions along the cochlea.
I'm also aware that the range of human hearing is roughly between 20 Hz and 20 kHz.
However, looking at ...
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Are there internal systems of organisms which acquired the functions which they were not evolved to perform?
In his research on the issue of belief formation Daniel Gilbert (1991. How Mental Systems Believe) claimed that cognition "is an evolutionary outgrowth of [perception]." What he meant is ...
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Would muscles still twitch if the applied potential is reversed?
In Galvani's experiment with frog legs, he applies an electric potential across the muscles of a frog which causes the leg muscles to contract. What would happen if the polarity was reversed (I do not ...
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what is the major mechanism of habituation?
I am learning the habituation and sensitization in Aplysia I understand the habituation occurs at the pre-synaptic side, but I see two different explanations, both of which sound reasonable to me and ...
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Functional unit
What is meant by functional unit of a system?
Like when we say that the neuron is the basic unit of neural system, do we mean that all those things that are performed by neural system can be performed ...
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Will lidocaine stimulate photoreceptors?
Lidocaine apparently blocks voltage-gated sodium channels in sensory neurons and thus prevents action potentials, but photoreceptors like rod cells require hyperpolarization (through blockage of its ...
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Unbounded synaptic weight in Hebb’s rule
I am new to neuroscience and apologies in advance if this is a very trivial question. I want to model the synaptic weights of neurons and using the discrete Hebb’s update rule
$$w_{n+1}=w_n(1+c)$$
...
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Molecular Signaling: Why is it more difficult to study membrane-bound signaling molecules compared to soluble ones?
I am reading the textbook Neuroscience (6th ed.) by Dale Purves and colleagues. In one of the chapters (Chapter 7, Molecular Signaling within Neurons), I am reading about the different types of ...
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Im struggling to see how these are presynaptic terminals/knobs and not post synaptic
How are these presynaptic terminals ? The action potential is generated at the axon hillock and moves down the axon (in this case to the right) , then at the end of the axon should be axon terminals ...
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If tinnitus is, in many cases, caused by damaged ear hair cells, couldn't it be solved by a mini cochlear implant that sends a constant signal?
If my understanding is correct, tinnitus is in most cases caused by damage to the inner ear hair cells, especially on the basal parts of the cochlea, which correspond to high frequencies. So, for ...
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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 ...
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Is there a good protocol for bilateral decortication in rodents?
I was thinking about using bilateral decortication in rodents (preferentially mice) to study the roles of certain brainstem areas in cognitive tasks in the absence of cortex. However almost all ...
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What are layers in the Blue Brain Project?
I was watching Bedlewo: Topology meets neuroscience when the lecturer mentions that data is available here. I might find it an interesting challenge to do some exploratory data analysis, but I want to ...
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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 me ...
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How does the central nervous system create the feeling of physical sensation in our consciousness? [closed]
I know sensory neurons that respond to light and physical sensations (pressure, temperature) exist throughout our body, giving us information about our surroundings.
For instance, when I push the tip ...
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Why does sympathetic activity constrict pulmonary vessels?
I don't know understand why sympathetic stimulation constricts pulmonary vessels?
I thought that the sympathetic nervous system activated the body for physical activity. Physical activity would need ...
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Why does the concentration gradient of one ion represent the entire cell in the equilibrium potential of an ion? [closed]
The Nernst equation for the equilibrium potential of an ion(in this case potassium),
$$E_{eq,K^+} = \frac{RT}{zF} \ln \frac{[K^+]_{o}}{[K^+]_{i}}$$
includes the ratio of the concentration of that ...
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Need help identifying vascular structures in brain matter
I am working on PET images of the brain. The neuro-oncologist I'm working with identified 2 large high-intensity regions as vascular structures. I've been meaning to ask what structures these are ...
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Why do neurons have only one axon?
I have just learnt about neurons. I wonder why neurons have only one axon. Can they transmit nerve impulses faster and more rapidly when they have more axons? Does having more axons help in ...
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Confusion regarding the location of myelinated and unmyelinated nerve fibres
So, what I understand by neural system terms is
Central nervous system [CNS]- consist of brain and spinal cord
Peripheral nervous system [PNS] - consist of cranial and spinal nerves (all the nerves ...
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