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Interesting question! An important factor here is the let-go phenomenon, which is defined as the current level in the arm that will cause the hand to involuntarily grip the current source. When the fingers are wrapped around a large cable, most adults will be able to let go with a current of less than 6 mA. At 22 mA, however, more than 99% of adults will ...


28

Short answer Yes, taste sensations can be generated electrically. However, we cannot taste electrons themselves, as taste-receptor proteins on the taste receptor cells are not activated by electrons. Instead, electrical currents stimulate taste receptors directly by depolarizing the cell membrane, without the need of activation of the proteins that normally ...


20

Devices that bypass the hair cells in the inner ear and directly stimulate the auditory nerve are called cochlear implants. Cochlear implants are used to treat deafness caused by the loss of hair cells in the cochlea. The hair cells are the sensory cells that convert sound vibrations into electric neural signals (Purves et al., 2001). With state-of-the-art ...


13

When the body comes in contact with an electrical power supply, two things can happen. If the current flow is high enough, the body heats up just like a heating resistor, and opposed to the resistor, the body can't handle the heat, thus severe burns occur after electric shock. But if the current is low enough not to burn "the conductor" other effects are ...


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Electrical currents stimulate neurons aspecifically. For example, the BrainPort artificial vision device conveys visual information through electrical stimulation of mechanoreceptors in the tongue. Similarly, cochlear implants and retinal implants convey acoustic and visual information through electrical stimulation of the inner ear and retina, respectively. ...


8

As @AliceD mentioned, cochlear implant is one of the earliest achievements of neural engineering. However, there are orders of magnitude more inner hair cells (IHC) and even more auditory nerve fibers (AN) in human cochlear than the current cochlear implants offer electrodes. If you are interested in a more detailed model of IHC to AN signal transmission, ...


7

I don't have the math at hand for the actually energy efficiency, but let's just start from the storage capacity. Basically, an electric eel wouldn't make a very good battery. They could be a decent, albeit fairly inefficient capacitor, but they actually store little energy. Using data from Wikipedia on Electric Eels it works out to something less than 2 ...


7

Nice Question! Lets first introduce ourselves to the topic i.e. Electrical Muscle Stimulation. Electrical muscle stimulation (EMS), also known as neuromuscular electrical stimulation (NMES) or electromyostimulation, is the elicitation of muscle contraction using electric impulses...The impulses mimic the action potential coming from the central nervous ...


5

In a PNAS paper by Palti's group (2007) they explain the hypothesis behind the technique: They reason alternating currents of 100 kHz to 1 MHz specifically affects dividing cells and thereby targets cancer cells. Note that this is the same basic idea as chemotherapy and radiotherapy, which also target dividing cells mostly. The mechanism of action of ...


2

The answer to your (excellent) question is a matter of definition, which has its roots in the 18th century. A cathode is the electrode where conventional positive current leaves a current source. Conventional current is positive, due to historic reasons. Around 1750, Benjamin Franklin described the flow of current between wool and wax after ...


2

Whether wireless power transfer is safe depends on the type of power transfer. Inductive coupling is generally safe, but only works across small distances (i.e., millimeters to centimeters). The other option is far-field or radiative technology, where either visible light (from lasers) or microwaves are used. The latter has not been applied much, some uses ...


2

Peterchev et al. (2010) reports The current amplitude is [... ] held fixed at the device maximum (e.g., 800 mA or 900 mA)... and that [constant-voltage devices are] now obsolete The total stimulus duration as I understand is a pulse train of a few seconds (Peterchev, 2010). The duration of total treatment is about 20 minutes in the treatment room ...


2

Short answer Although outside my direct area of expertise, there is quite a lot of literature on the topic. The trick often is to use the correct keywords. Key in "recording + stimulating + ensemble + neurons", or "Utah + neuron + implant". Background There is quite some literature on this topic. For instance, a much used device in this arena is the Utah ...


2

Unfortunately, I haven't looked at this sort of literature for a long time, but here are some thoughts with which to start. Your question is about "spatiotemporal patterns" of neural systems. One of the first things that comes to mind is neural oscillations (e.g. alpha waves). This is essentially looking for the presence of "frequency patterns" in the ...


2

Sensory receptors and neurons get their selectivity from physical processes and their position in space. For example, photoreceptor cells in the retina respond to light in a specific position in space because the lens and structure of the eye directs light incoming in a particular angle to a specific spot on the retina. Sensory receptors in the skin can ...


1

I'll try to answer the sub questions 1-by-1 Does that mean that the change in membrane potential that I did resulted in changes in the conformational states of ion channels which in turn changed the membrane potential that I need to control ? It's the other way around; your book is right - "When the membrane potential is suddenly increased by this ...


1

Is there a physiological reason why direct lightning strikes are not lethal for everyone or does it all come down to dumb luck? To be lethal a lighting strike has to do enough damage to a critical organ that the injury is not survivable. Since electricity can take highly variable paths through a body, the amount of damage inflicted is also highly variable. ...


1

None of the three scenarios you describe are really different from another. Whatever process is used inside the amplifier, a voltage describes a potential difference between two points. It does not relate that to any other universal reference. If you have a ground connection, you could describe a different potential relative to ground, but that's not ...


1

The situation is quite reminiscent of a Voltage clamp experiment (Fig. 1), where one amplifier (amplifier 1 in Fig. 1) records the potential difference (V1 - V2 in Fig. 1) between two electrodes and the other opamp (2) is used to inject current (I2 in Fig. 1) to 'clamp' the system at a particular voltage using a computerized feedback system. The potential ...


1

Short answer Both anodic and cathodic current pulses can evoke neural activity, as shown in your image. Background You have to be aware that the current direction is arbitrary and the 'convention' you mention depends on your discipline. In electrophysiology, the anode is generally considered to be the positive electrode, the cathode is generally the ...


1

In practice, focal electrical stimulation of the brain can be used to prevent or abrogate seizures. There is a device marketed for this. from https://www.scientificamerican.com/article/implant-epilepsy-seizure/ NeuroPace's Responsive Neurostimulation System (RNS), an electrical-stimulation implant with two leads, each containing four electrodes, ...


1

Yes, but maybe not how you think. It is important to recognize that voltages refer to potential differences. When we say the "a cell is at -65mV" for example, we mean "The potential difference across the cell's membrane to the extracellular space is -65mV." When you stimulate electrically, you create a transient electric field, whereby the extracellular ...


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