Questions tagged [neuroscience]
The study of the structure and function of the nervous system and its components.
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Can Cells Be Trained?
A long time ago, I heard (from what source? I do not remember clearly)
that there were studies of the effects of the mind on cellular activities. Vaguely, I remember that it concerned
an increase in ...
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14 views
Does human reasoning work exactly as in daytime conscious state while during dreams? [closed]
Since childhood I may have slept around 8000 times. I have seen many dreams but all of them (which I remember) have extremely poor reasoning. For eg. I put my book in my cupboard and locked it and ...
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3answers
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If the Brain can store as much information as a billion hard disks why cant i memorize a single word document of random letters?
I read a lot of articles on this and all seem to agree that the brain storage in neural connections is tremendous but that doesnt explain why we forget things so easily and have such a modest memory ...
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Why are the sympathetic and parasympathetic axons different, in terms of presynaptic and postsynaptic length?
Does the parasympathetic system have a long presynaptic efferent axon because it takes a great distance to reach target organs from the brain stem or sacral region of the spine? Does the sympathetic ...
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health and well being
I have heard that the earth's magnetic field will effect you when you sleep. My wife and I lie in an east/west orientation with our heads to the west. Does the direction you lay in bed and sleep ...
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Alzheimer's datasets highlighting role of individual genes
A question to the folks who studies Alzheimer's disease here.
My colleagues and I have developed a new program that predicts the master regulators based on transcriptomic changes (yes, another one). ...
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1answer
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Vitamin A Deficiency
I have a quick question regarding Vitamin A deficiency.
The photoreceptor molecules in both rods and cones have the same general structure which is retinal which is bound to a protein called opsin ...
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are all cells in our body connected with the nervous system?
do all cells in our body have receptors on them or even connected with gap junction so that synapses of neurons can occur with them?
i saw another question which says "will a cell die if it got ...
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1answer
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First neurotransmitter?
Cnidaria are considered to be the first phyla to develop a nervous system. Nervous systems having 1, 2 and three neurons are considered to have appeared first in Cnidaria, with 2-neuron nervous ...
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Adding potassium outside of neuron: Hyper- or De- polarization?
At rest, the equilibrium potential for potassium given by the Nernst equation is ~ -80mV. Since the cell is mainly permeable to potassium, this is the reason for the cell membrane's rest potential to ...
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Doubt related to nerve impulse transmission
Naturally, the extracellular fluid has more sodium ions and the axoplasm has more potassium ions. Since there are more potassium leakage channels than sodium leakage channels on axoplasm, it is more ...
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1answer
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Visual receptive fields
What I know about centre-surround type receptive fields is that depending on whether the region is on or off, the response to being stimulated is either excitatory or inhibitory respectively. So if a ...
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1answer
27 views
Synapses of inhibitory neurons
I sometimes read of "inhibitory synapses". But I understand that when the neuron is inhibitory, all of its synapses will be inhibitory (so it is a property of the neuron, not only the synapse) - is ...
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1answer
39 views
What is the significance of the amplitude of brain waves?
What does the amplitude of brain waves represent and to what neuronal activities is this amplitude related to?
For example, in a hypothetical situation, the frequency of brain waves is kept the same, ...
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120 views
What brain regions consume the most energy?
It's well known that the human brain consumes roughly 20% of the body's energy, and that grey matter is much more energy-intensive than white matter.
Beyond this basic information, it seems difficult ...
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1answer
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Meaning of “external demands” in a paper describing the gut-brain axis
From "Brain Gut Microbiome Interactions and Functional Bowel Disorders":
In response to external and bodily demands, the brain modulates individual cells (ECC – enterochromaffin cells; SMC – ...
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Does the brain absorb heme and non-heme iron differently?
I know that for the brain to absorb iron, the iron must first pass through the blood brain barrier. Is this absorption different for heme and nonheme iron?
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How does lactic acid cause muscle twitching?
It is well-known that lactic acid buildup (often caused by workouts) causes muscle twitching.
Does anyone know HOW lactic acid achieves that effect?
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Which hormones, metabolites, or other molecules build up as the day progresses, other than melatonin and adenosine?
Melatonin and adenosine reach peak levels around midnight/bedtime. I was wondering what other molecules also buildup as the day progresses. Particularly molecules that affect the CNS and/or immune ...
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Biophysically, how to change from a tonically firing neuron to an occasionally firing one?
In terms of membrane properties, size and neuronal biophysics (assuming no change in incoming excitation), how can a tonically firing neuron become (say during development) an occasionally bursting ...
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Are “sympathetic nerves” the same as “cardiopulmonary splanchnic” nerves?
I've gathered from a number of sources (e.g., Patel (2015), Wikipedia, and here) that the sympathetic nerves leaving the sympathetic trunk to innervate the heart and lungs are called "cardiopulmonary ...
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Would it be possible to determine the strength of each neural connection in a connectome data set?
I understand that a connectome is a map of connections between neurons.
Would it be possible with current day technology to create a more detailed map that gives not only the connections themselves ...
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1answer
133 views
Are there people blind to touch?
There are people who completely blind or deaf. Are there people who are completely blind to touch in a particular area or in the entirety of their body? If not, are there people in whom the ...
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1answer
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What does it mean to say that the sympathetic nervous system is organized for diffuse activity?
"Sympathetic activities generally serve to mobilize the energy stores of the body, to increase the blood flow through certain regions (e.g., the heart) at the expense of other areas (e.g., the ...
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1answer
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Why isn't hearing the same as tasting? How do we feel and differentiate external stimuli?
When I was at school, I learned that:
Skin, tongue, ears, and other sensory organs have sensors/convertors that turn external environment stimuli into "electric" signals.
Neurons send information as ...
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1answer
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What does sympathetic and parasympathetic 'tone' mean?
My professor's lecture notes say that " The basal rate of firing is called “sympathetic tone” and 'parasympathetic tone" , but a table I found on the internet says that the parasympthetic system has ...
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1answer
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Question about the Derivation of the cable equation for neurites
I read in Wikipedia how the cable equation was derived (here) and had a specific problem regarding one of its equation:
At the start of the derivation it states that we first need to pretend that the ...
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Why doesn't the spinal cord get thicker the further up we go?
The cervical and lumbar enlargements exist on the spinal cord as a result of the increased nerve input/output required for the arms and legs respectively.
However, I don't understand how the ...
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1answer
29 views
Why the length constant of passive current flow isn't depend on the membrane capacitance?
I read that the equation for the length constant for passive conductance along a neuron depend on the resistance of the plasma membrane, the intracellular axoplasm and the extracellular medium. My ...
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1answer
16 views
Is there any case in which excitability increases with lowering the RMP?
My professor says , at a more negative RMP, less sodium ion channels are inactivated, so if you take 2 of the exact same neuron with the same threshold potentials, and try to excite them starting from ...
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1answer
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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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1answer
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Why is the ratio between action potential and threshold value called the 'safety factor'?
"AllorNothing Principle. Once an action potential has been elicited at any point on the membrane of a normal fiber, the depolarization process travels over the entire membrane if conditions are ...
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1answer
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By what physiological mechanism do we not feel microbes (bacteria, etc.) living on our skin?
Background
I know our bodies have a handful of ways to threshold our awareness of sensory stimuli:
Neural density
Sensory acuity
I assume really tiny stimuli could fit between receptors
e.g., ...
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1answer
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Is there in vivo evidence of Amyloid beta toxicity?
Amyloid beta is thought to be toxic, however from a brief search, this is based on (1) in vitro (2) measurements of some proxies of toxicity (e.g. Ultrasensitive Measurement of Ca2+ Influx into Lipid ...
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Schematic of neural lineage tree and position of Choroid Plexus cells
I am trying to understand which are the different type of progenitors in the human brain and I am currently following this schematic.
My question is, are Choroid Plexus cells progenitors to Radial ...
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Breakdown of functional human genome by organ/What fraction of the functional human genome is devoted specifically to brain functioning?
Of course, there won't be a precise known answer to the question, as it is not even known precisely what percentage of the genome is functional in the first place - but I am still looking for research....
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Understanding the ECG waveform with respect to Lead Positions
I am really confused about the Representation of potential in an ECG graph.
First i will ask what is on the vertical axis? (I guess it is electrical potential in millivolts)
But again it changes for ...
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1answer
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What is the function of dreaming? Does a particular hormone secretion interfere with dreaming? Why do some people dream more?
I'm really interested to know when we are sleeping how a series of stories come to our mind that we called this process dreaming. If you know a useful article on this topic, please tell me thanks.
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1answer
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Why do biologists judge intellect based on brain size?
I have seen many times, that scientists will say Species A is smarter than Species B due to a higher brain-to-body ratio. I've even seen similar arguments made by comparing the sizes of specific ...
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1answer
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Has anyone attempted to add extra senses to a creature through a BCI/Neural interface?
Basic BCI's (Brain computer interfaces) have been available for quite a while now and allow users to preform rudimentary tasks such as moving prosthetic limbs with force-feedback or moving a mouse on ...
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1answer
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What does microglia process length tell us?
I'm reading a study investigating traumatic brain injury and alcohol consumption and the researchers measured microglia process length as an indicator of brain damage. I was wondering what that would ...
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1answer
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Inhibitory functional connectivity
Functional connectivity may be defined as
»the temporal correlation between spatially remote neurophysiological events, expressed as deviation from statistical independence across these events in ...
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Is relative timing of signal transmission between neurons along axons and through synapses relevant in the brain?
A neuron may be part of a nerve connection between two endpoints, transferring a signal that is not very sensitive to variations in signal propagation speed.
But a neuron inside a cluster of ...
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48 views
Long-term potentiations that last for a lifetime
One reads more often than not that
long-term potentiation has been reported to last for as long as several weeks
LTP is persistent, lasting from several minutes to many months
and most sources seem ...
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1answer
55 views
Ion-gated ion channels
Today I've heard for the first time of calcium-gated ion channels but find it hard to get an idea how they work, where they are located, and which role they play.
I assume calcium-gated ion channels ...
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1answer
135 views
Differences between neurotransmitters and neuromodulators
According to the Wikipedia article on neuromodulation
a neuromodulator can be conceptualized as a neurotransmitter that is
not reabsorbed by the pre-synaptic neuron or broken down into a
...
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Typical firing patterns of neurons in the default mode network in resting state
Inspired by the Wikipedia article on the default mode network where I read:
Hans Berger, the inventor of the electroencephalogram, was the first
to propose the idea that the brain is constantly ...
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Functional roles of firing patterns
Eugene Izhikevich reports – e.g. here – a plethora of neural firing patterns:
My question is two-fold:
Is there an overview which types of neurons are capable of (and typically exhibit) ...
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1answer
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Parts of the brain pivotal for maintaining consciousness
From an answer to another question (on conscious experiences by coma patients) I have learned that
no conscious experiences, complex thoughts, or complex emotions can
occur when one is in coma (...
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1answer
115 views
How does the dopamine spike from drugs compare quantitatively to pleasurable non-drug activities?
I did find this popular press article that quotes a researcher offering the following quantification: "in lab experiments done on animals, sex causes dopamine levels to jump from 100 to 200 units, and ...
