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- Glossary
Releasing hormone
Hormones of the hypothalamus that promote the release of other hormones in the adenohypophysis.
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- Glossary
REM sleep
"REM" stands for "rapid eye movement" – and rapid eye movements are also characteristic of REM sleep. During the course of a night, we go through several such REM phases, which are interrupted by non-REM phases. REM sleep is characterized by rapid eye movements, low-amplitude brain activity of mixed frequencies, and reduced muscle tone. Pulse and respiratory rate, on the other hand, are increased. In addition, we dream particularly vividly and intensely during these phases. People who are awakened from REM sleep often report vivid, concrete, and emotional dreams, while those awakened from non-REM sleep tend to report more abstract dreams that resemble thoughts.
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- Glossary
Retinal
A chemical synthesized from vitamin A. Together with opsin, it forms rhodopsin.
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- Glossary
Retrograde amnesia
A form of memory disorder in which memories from before the damage occurred can no longer be retrieved. The affected period can vary greatly and range from just hours before the event to entire decades.
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- Glossary
Receptive field
The receptive field is the area of the environment in which a stimulus changes (increases or decreases) the activity of a specific nerve cell.
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- Glossary
Receptor
A receptor is a protein, usually located in the cell membrane or inside the cell, that recognizes a specific external signal (e.g., a neurotransmitter, hormone, or other ligand) and causes the cell to trigger a defined response. Depending on the type of receptor, this response can be excitatory, inhibitory, or modulatory.
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- Glossary
Rhodopsin
A specific opsin found in the rods of the retina.
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- Glossary
Cortical blindness
When the primary visual cortex is destroyed, those affected are effectively blind, even though their eyes are undamaged. However, they are often unconsciously able to grasp and catch objects and even name them when asked to guess. This effect is known as blind sight.
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- Glossary
rostral
A positional term – rostral means "towards the beak." In relation to the nervous system, it refers to a direction along the neural axis towards the front, towards the face. In animals (without upright gait), the designation is simpler, as it always means located toward the front. Due to the upright gait of humans, the brain bends in relation to the spinal cord, making rostral at the level of the back become "up."
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- Glossary
Spinal cord
The spinal cord is the part of the central nervous system located in the spine. It contains both the white matter of the nerve fibers and the gray matter of the cell nuclei. Simple reflexes such as the knee-jerk reflex are already processed here, as sensory and motor neurons are directly connected. The spinal cord is divided into the cervical, thoracic, lumbar, and sacral spinal cord.
