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The question is relatively broad and one should take into account that the brain not only consists of neurons, but also glial cells (supportive cells) and pre-mitotic neuronal stem cells. Furthermore, as critical fellow-scientists have indicated, developmental stage is very important, as the developing embryonic brain is very different from the adult brain. ...


9

Probably don't do any experiments that involve shoving reptiles in a sack and swinging them around your head, as someone will surely call the ASPCA on you. The type of dizziness that is associated with spinning around is called "vertigo". From wikipedia: Repetitive spinning, as in familiar childhood games, can induce short-lived vertigo by disrupting ...


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Dizziness is caused by a continuing rotation of the fluids in the semi-circular canals of the vestibular system that transmit rotation information to the brain. After prolonged rotation of the body, the circular canal fluids are engaged in a rotating motion. This fluid motion continues even when the body has stopped moving. The persistent fluid rotation is ...


6

“Self-induction” in photosensitive epilepsy is a well-described and fascinating phenomenon. Photosensitivity itself is rare, occurring in only ~5% of patients with epilepsy.1 Among this group it has been estimated2 that 25% self-induce epileptiform activity. The most common methods appear to be passing a hand with open fingers repeatedly across the visual ...


4

It depends to some degree on what you define as peripheral vision. Until relatively recently, color vision in the peripheral field has been thought to be substantially less developed than color vision in the central field. Most estimates of peripheral color perception place the limit of trichromatic (RBG) vision at no more than 30 degrees from fixation; ...


3

High sodium extracellularly means an increased sodium concentration gradient across the membrane. This means there is a larger driving force for sodium to enter the cell once the sodium channels open at the start of the action potential, and hence a larger depolarization takes place increasing the action potential amplitude. The enhanced depolarization leads ...


3

There are two types of photoreceptor in the eye, known as rods and cones. Rods are spread equally throughout the whole retina, whereas cones are focussed in one spot known as the fovea: Cones are the only type of photoreceptor that can sense colour, so rods can only sense black and white. However, rods can work in much lower light and will also work when ...


3

The phenomenon Synesthesia is a neurological phenomenon in which a stimulus in one sensory or cognitive pathway triggers an experience in another. Some hallmarks:1 It tends to be developmental, arising early in childhood. It is involuntary. It is stable over time (i.e. the same stimulus leads to the same sensory experience). Epidemiology The best ...


3

Balance is tricky and depends on a lot of things, including, to some degree, your sight. Balance is achieved and maintained by a complex set of sensorimotor control systems that include sensory input from vision (sight), proprioception (touch), and the vestibular system (motion, equilibrium, spatial orientation); integration of that sensory input; and motor ...


3

Memories are dynamic; that is not equivalent to "memories are evanescent". Cellular structure and composition controls memory, not just a continuous passage of signals. This point is already discussed in the comments. Loss of energy (in the form of ATP) would cause memory deterioration and in some cases neuronal cell death too— strokes, which happen due to ...


3

Summary Working memory on a current task could be distorted, but I cannot find a reason to suggest sudden loss of electrical information would permanently alter short or long term memory. Hopefully a neuroscientist can answer with a more electro-chemical oriented answer, but fundamentally I think the experts aren't sure what a memory actually is (there are ...


2

I have gone through quite a number of papers using this virus, but I haven't found any definite answer on the maximum insert length. There is an indirect answer, though. The two articles cited below both report possible insert length of up to 3.7kb without any experimental problems. This insert length results in a viral genome which is about 1.9kb longer ...


2

You are correct that hydrophobia is often considered pathognomonic of rabies. However, I offer for your consideration: Hydrophobia as a rare presentation of Cotard's syndrome: a case report.1 Cotard's syndrome itself is a bizarre psychiatric condition that the authors of the above paper define well: Cotard’s syndrome is a rare condition where the ...


2

Interesting question! There has been at least one study that bypassed a spinal lesion site with autografted neuronal tissue (Tadie et al., 2004 - doi:10.1089/089771502320317069). The study participant regained voluntary motor skills 8 months after bypass surgery. The surgery involved the implantation of nerve autografts between the rostral spinal ventral ...


2

It is definitely possible to include antibodies and other biological molecules in formula to better approximate that of its mother's milk. However, there's no way you could mass-produce this. Every mother has unique antibodies, even horomones that are the same in different people are present at different concentrations. The current "formula" on the market ...


2

These hormones are progesterone and estrogens. They are actually secreted by the placenta, in increasing amounts as the fetus matures: (Colorado State, R. Bowen) You can see that the placenta produces both types of hormone in increasing amounts until birth. Additionally, the hormone relaxin is secreted by the placenta and thought to aid in parturation: ...


2

Anger is a common emotion in most animals and it is highly related to stress. At time of anger body usually releases stress hormones and the body's way to respond to stress is by sympathetic nervous system activation which results in the fight-or-flight response. Anger is an emotional response related to one's psychological interpretation of having been ...


2

Not different from @ChrisStronks answer. Just in different words. Just for everyone's knowledge — you are referring to the Voltage-clamp experiment. Situation 1: Sodium is depleted in the ECF. Despite the fact that Na+ conductance is much less than that of K+ and the equilibrium membrane potential (hyperpolarized) is closer to Nernst potential of K+, ...


1

Dopamine is one of many neurotransmitters which modulate information passage between one brain area to another. Dopamine is thought to play important role in pleasure, addiction, and learning.Massive increase in the amount of dopamine released in the brain during video game play, the releasing of dopamine are in areas thought to control reward and ...


1

The answer can be found in PubChem, which is linked in the comment by anongoodnurse. I would not say that Norepinephrine is beta2 adrenomimetic because norepinephrine has many roles such as neurotransmitter. I would just say that Norepinephrine is alpha, beta adrenoagonist. More pieces of information about it from PubChem:


1

This isn't a ridiculous idea; Transcranial Magnetic Stimulation is used in research and even has some use as treatment for depression (http://www.mayoclinic.org/tests-procedures/transcranial-magnetic-stimulation/basics/definition/prc-20020555) In TMS a strong, localized magnetic field can disrupt normal functioning of regions of the brain. For instance it ...


1

It is possible to tag molecular motors with fluorescent proteins. It may impede with its movement but as this paper describes, a variant can be created that doesn't have cargo binding ability. Constitutively active kinesin motors can be generated by truncations that remove autoinhibitory and cargo-binding regions of the polypeptide. For this work, ...


1

Very nice question! I'll go through your three questions sequentially. Q1: Why does lower capacitance increase "the effectiveness of nearby nodes" or allow the depolarizing voltage to "travel not by ion diffusion, but as an electric field"? A: Capacitance basically results in sequestering of charge of opposite polarities along the cell membrane, which ...


1

The Hodgkin-Huxley model: $$I=C_m\frac{dV}{dt} + g_k(V_m - V_k) + g_{Na}(V_m - V_{Na}) + g_l(V_m- V_l)$$ Where $C_m$ is membrane capacitance per unit area and $g_i$ are membrane conductances. Reducing the number of channels does not affect capacitance; it basically reduces membrane conductance. Myelination causes reduction of number of channels ...


1

Most of the time, calcium is not the most important ion in terms of active propagation of an action potential along an axon. It is usually sodium and potassium which play the key roles here. In most living things the concentrations of ions for the intracellular and extracellular solutions are similar. For an action potential, you usually have an influx of ...



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