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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.
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- Glossary
Lock and key
In terms of the processes in a synapse, this means that the chemical messenger and its receptor must fit together like a key in a lock. The receptor therefore only "accepts" a very specific messenger.
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- Glossary
Pain memory
Acute pain can become chronic if it persists for a long time or if the nervous system becomes permanently sensitized. Due to its plasticity, the nervous system can then react to even slight stimuli with pain, even if these would normally be harmless.
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- Glossary
Criminal responsibility
In a neuroethical context, the issue of "culpability" arises from the question of whether humans possess free will: only when someone commits an act of their own free will can it be morally evaluated. Based on their research findings, some leading neuroscientists argue that humans do not possess free will. According to this view, even criminals are not responsible for their actions. If this way of thinking were to prevail, it would have significant legal implications in addition to moral ones.
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- Glossary
Visual pathway
The visual pathway refers to the network of nerve cells involved in visual perception. In mammals, it runs from the retinal ganglion cells in the eye – as the optic nerve to the optic chiasm, then as the visual tract – via the only switching point in the lateral geniculate nucleus to the primary visual cortex.
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- Glossary
Optic nerve
The axons (long fiber-like extensions) of the retinal ganglion cells form the optic nerve, which leaves the eye at the back of the optic disc. It comprises approximately one million axons and has a diameter of approximately seven millimeters.
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- Glossary
Visual radiation
The optic radiation – also known as Gratiolet's optic radiation after its discoverer – distributes visual impulses from the lateral geniculate nucleus to the comparatively very large primary visual cortex.
