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- Glossary
Supraoptic nucleus
A core area of the hypothalamus, located above the optic nerves. This is where the peptide hormones vasopressin and oxytocin are produced.
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- Glossary
Nucleus tractus solitarius
A nucleus in the medulla oblongata that serves as an important integration center for visceral information. Among other things, it processes taste stimuli (via nerves VII, IX, and X) and transmits them via the thalamus (ventral posteromedial nucleus, VPM) to the primary gustatory cortex. The NTS is also involved in the motor functions of swallowing, coughing, and respiratory control by transmitting signals to motor nuclei such as the nucleus ambiguus. These reflexes serve to protect the respiratory tract and facilitate food intake.
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- Glossary
Posterior ventral nucleus
A nucleus of the dorsal thalamus that serves as the main somatosensory thalamic nucleus. The VPL receives somatosensory afferents from the body via the spinal cord (pressure, touch, vibration, proprioception, pain, temperature), while the VPM receives afferents from the head region via the trigeminal nerve. It transmits this information to the primary somatosensory cortex (S1) and thus plays a central role in the awareness of somatosensory stimuli, including pain.
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- Glossary
Ear
The ear is not only the organ of hearing, but also of balance. A distinction is made between the outer ear with the auricle and external auditory canal, the middle ear with the eardrum and ossicles, and the actual hearing and balance organ, the inner ear with the cochlea and semicircular canals.
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- Glossary
Ear canal
Sound waves captured by the outer ear enter the external auditory canal and cause the eardrum at the end of the canal to vibrate.
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- Glossary
Occipital lobe
One of the four large lobes of the cerebral cortex. The occipital lobe lies above the cerebellum. It borders the parietal and temporal lobes at the front. The calcarine sulcus divides the occipital lobe into an upper and lower half, the cuneus and the lingual gyrus. Functionally, this area of the brain is responsible for the central processing of visual information – both the primary and secondary visual cortex are located in the occipital lobe.
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- Glossary
Olfactory cortex
The olfactory cortex comprises the structures of the cerebrum that are responsible for processing olfactory information. The primary olfactory cortex is the prepiriform cortex, an evolutionarily ancient part of the cortex (paleocortex) with a three-layer structure.
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- Glossary
Oligodendrocytes
Cells of the central nervous system that form the myelin sheath around nerve cells, thereby increasing their conduction velocity. They belong to the glial cells.
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- Glossary
Oligomer
Chemists define an oligomer as a molecule composed of several structurally similar or identical units. Typically, an oligomer consists of a few monomers (e.g., 2–10, occasionally up to about 30). An example from biochemistry is collagen, which is composed of three identical polypeptide chains and occurs as a trimeric protein in connective tissue. If the number of building blocks significantly exceeds this range, as is the case with DNA, it is referred to as a polymer. Oligomers of beta-amyloid may play an important role in the development of Alzheimer's disease.
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- Glossary
Olivary bodies
The olivary bodies are two oval structures in the lower part of the brain stem that contain clusters of nerve cell bodies. The lower olive connects the cerebrum to the cerebellum and plays an important role in controlling motor function. The upper olive is part of the auditory pathway. Its neurons can evaluate differences in transit time and level between the right and left ears, thus helping to determine the direction of sound sources.
