New answers tagged neuroscience
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Essentially all animal cells maintain an ionic balance causing a resting potential of about -70 mV in order to maintain their internal environment including pH, ion concentrations, osmotic pressure and volume. (Lodish, Molecular Cell Biology) Neurons developed from existing types of cells and it's unlikely that the cost of maintaining resting potential in ...
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No, the brain does not use microcode, nor even code (as that term is used with computers). The brain is not a digital stored-program computer as that is understood in computer science. It has some digital aspects in that the pulses neurons transmit are essentially on/off states, but they are used in pulse trains rather than as bits. The operations that ...
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According to the article: Scientists uncover second depth-perception method in the brain:
the neurons in the middle temporal area of the brain are combining visual information and physical movement to extract depth information
This Scientific American article states that there is a process involved:
Visual-image processing from the eye to the brain ...
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There are two factors that need to be taken into account here:
1. Myelination decreases membrance capacitance.
The rate at which sodium influx through a node can depolarize the axon at the next node is related to both the current and capacitance across the membrane (in addition to a few other factors). So while adding a new node to the axon would indeed ...
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There are indeed 'gap junctions' which pass current directly from one cell to the next. So what advantages do we get out of chemical synapses that gap junctions do not provide?
Asymmetry. Synapses to not operate in reverse, thus the postsynaptic cell cannot generate currents in the presynaptic terminal (although there are secondary forms of communication ...
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The vagus nerve controls heart rate. This is the best example of a direct nerve action potential impacting cardiac muscle, although one could argue the adrenaline system to be an indirect mechanism.
The vagus nerve is part of the parasympathetic system, it acts to decrease heart rate. Resting heart rate is maintained by permanent vagal stimulation/tone by ...
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There is nothing special about the use of rhodopsin when compared to making a cell express any transgene. This question can then be read as:
What is the process in which a cell population is targeted and implanted with a gene of interest?
There are many ways, which depend on the specific cell type and on whether you want to do it in vitro, in vivo and ...
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I searched around and came across this article: http://fitness.stackexchange.com/questions/2017/why-is-muscle-size-not-proportional-to-strength
As it turns out those who build muscle go for the higher rep range with moderate weight, training as you stated for hypertrophy and in turns increases sarcoplasmic fluid build up.
This will indeed make the muscle ...
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It's important to note the difference in mechanism between cocaine and meth. While cocaine blocks reuptake, meth makes VMAT - vesicular monoamine transport - leaky and actually reverses the transportation of dopamine, so that instead of transporting dopamine into the axon terminal, it actually transports dopamine out as it leaks from the vesicle that carry ...
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The wiring is different as you mentioned. However, perhaps the most important is the brain knows where it's input is coming from. The brain knows where each fibre innervates and thus can compile and present this data to our conscious mind. We show if we stimulate the brain directly, than we feel a sensation in the part of the body that portion of the brain ...
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Not so empty, actually.
The human brain has a mass of ~1.5kg, and volume ~1200cc (a little bigger for men, a little smaller for women). So is heavier than water by a good margin.
While it has Cerebrospinal fluid, that only occupies the subarachnoid space (the space below the skull and above the cortex, contained between two layers: pia matter and arachnoid ...
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Apologies for just referencing Wikipedia, but this is a very old bit of science.
The neuron gap junction - the point where the axon touches the next cell over - is 4 nanometers.
This is actually a controlled channel where the neuro transmitter molecules are transferred from one cell interior to another - its a controlled cellular - cellular channel so ...
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Shampoo contains surfactants, chemicals which cause lipids to emulsify. The cell membrane is composed primarily of phospholipids, which are vulnerable to action by surfactants. In fact, sodium dodecyl sulphate (SDS, often labelled SLS on shampoo bottles), an integral component of many shampoos is also used in the lab (albeit at substantially higher ...
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The author is likely referring to the mechanosensory behavior of bone (reviewed in Huang and Ogawa, 2010; lots of Google Scholar citations). Bone loading produces very tiny mechanical deflections (strain) which are translated into biochemical signals that promote bone growth through the action of osteoblasts. Burger and Klein-Nuland (1999) review possible ...
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