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- Glossary
Bulbous corpuscle
Bulbous corpuscles – or Ruffini corpuscles – are slow mechanoreceptors that detect skin stretching and joint movements.
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- Glossary
Resting potential
The membrane potential of a neuron at rest. The inflow and outflow of ions are in equilibrium. It ranges from –50 to –100 mV.
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- Glossary
Round window
The round window is a membrane-covered opening in the cochlea on the middle ear side. It is connected to the scala tympani and enables the necessary pressure equalization in the inner ear when sound is transmitted through the oval window.
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- Glossary
Saccade
Rapid eye movement, which usually occurs unconsciously. It is a quick and jerky movement of the eyes, in which the eye spontaneously focuses on an object. When reading, for example, the eyes jump from one short word to the next. During a saccade, visual information processing is greatly reduced.
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- Glossary
Saltatory conduction
The term is derived from the Latin "saltare" – to jump. And this is exactly what an impulse does along a myelinated nerve: it jumps from one Ranvier node to the next, which greatly increases the speed of nerve conduction.
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- Glossary
Tympanic duct
The tympanic duct or scala tympani is the lower of the three canals of the cochlea. Like the scala vestibuli, this canal is also filled with a lymph-like fluid.
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- Glossary
Vestibular duct
The vestibular duct or scala vestibuli is the uppermost of the three canals of the cochlea and is filled with perilymph. At the oval window, the movements of the stapes transmit vibrations to the perilymph of the scala vestibuli. These vibrations set the basilar membrane in motion and thus indirectly influence the middle canal, the scala media.
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- Glossary
Sleep phases
During sleep, we go through several non-REM/REM cycles, each lasting around 90 minutes. The non-REM phases consist of stages N1, N2, and N3, with slow delta waves with frequencies of 0.5–2 Hz dominating in N3 (deep sleep). REM sleep is characterized by rapid eye movements, low-amplitude, mixed-frequency brain activity, and greatly reduced muscle tone. Deep sleep predominates at the beginning of the night, while the proportion of REM sleep increases in later cycles.
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- Glossary
Sleep disorders
A collective term for various phenomena characterized by the fact that those affected do not get restful sleep. Both psychological and organic causes can contribute to this. Symptoms range from problems falling asleep and staying asleep to undesirable behaviors during sleep such as sleepwalking, restless legs when falling asleep, sleep apnea, etc. According to estimates, up to 30 percent of all adults in Western countries suffer from some form of sleep disorder. Finding the causes is often complicated, and analysis in a sleep laboratory is the best method of investigation.
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- Glossary
stroke
In a stroke, the brain or parts of it are no longer supplied with sufficient blood, which impairs the supply of oxygen and glucose. The most common cause is a blockage in an artery (ischemic stroke), less commonly a hemorrhage (hemorrhagic stroke). Typical symptoms include sudden visual disturbances, dizziness, paralysis, speech or sensory disturbances. Long-term consequences can include various sensory, motor, and cognitive impairments.
