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- Glossary
Neocortex
The neocortex is the phylogenetically youngest part of the cerebral cortex. Since it is structured relatively uniformly in six layers, it is also referred to as the isocortex.
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- Glossary
Retina
The retina is the inner layer of the eye covered with pigment epithelium. The retina is characterized by an inverse (reversed) arrangement: light must first pass through several layers before it hits the photoreceptors (cones and rods). The signals from the photoreceptors are transmitted via the optic nerve to the processing areas of the brain. The reason for the inverse arrangement is the evolutionary development of the retina, which is a protrusion of the brain.The retina is approximately 0.2 to 0.5 mm thick.
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- Glossary
Neurodegeneration
Collective term for diseases in which nerve cells gradually lose their structure or function until they eventually die. In many cases, misfolded proteins are the trigger – such as certain forms of the proteins beta-amyloid and tau in the case of Alzheimer's disease. In other diseases, such as Parkinson's disease or Huntington's disease, proteins within the neurons are not broken down properly. As a result, toxic aggregates are deposited there, leading to the respective disease symptoms. While Huntington's disease is clearly genetic, in Parkinson's and Alzheimer's there appear to be certain gene variants that promote their development. None of these neurodegenerative diseases can be cured at present.
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- Glossary
Neuroenhancement
Neuroenhancement is about improving cognitive performance. To this end, drugs used to treat dementia, hyperactivity, or narcolepsy are taken by healthy individuals with the aim of improving their learning abilities, increasing their alertness, or staying awake and active for longer. In addition to the ethical questions this raises, there is also medical controversy as to whether this self-medication actually works and what the long-term consequences might be.
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- Glossary
Neurofibrils
Neurofibrils are fine fibrous structures in nerve cells that consist mainly of neurofilaments (a form of intermediate filaments) and other components of the cytoskeleton. They run in bundles through the cell body and the extensions of neurons and contribute significantly to the stabilization and shaping of the nerve cell. They appear as characteristic features of neurons even in the early embryo. Alzheimer's disease causes profound changes in cytoskeletal structures: the protein tau, which normally stabilizes microtubules, becomes excessively phosphorylated, detaches from the microtubules, and aggregates to form the typical neurofibrillary tangles (fibrillary bundles). These are a central pathological feature of the disease.
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- Glossary
Neurohypophysis
The neurohypophysis is the posterior lobe of the pituitary gland. It stores the hormones oxytocin and vasopressin, which are produced in the hypothalamus, and releases them into the bloodstream when needed.
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Neuromarketing
A relatively new, interdisciplinary field of research in market research that builds on the findings of neuroeconomics – and is not entirely without controversy. The concept of neuromarketing is based on the assumption that customers make purchasing decisions primarily on the basis of unconscious emotional reactions. Neuromarketing uses neurophysiological measurement methods to study these reactions in order to better understand how consumers respond to products, advertising, and sales environments – with the aim of influencing these responses and thus purchasing decisions at the point of sale (the store) through measures such as music or scents.
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- Glossary
Neuron
A neuron is a specialized cell in the nervous system that is responsible for processing and transmitting information. It receives signals via its dendrites and transmits them via its axon. Transmission occurs electrically within the neuron and, between neurons, usually chemically via synapses.
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- Glossary
Neural representation
Various parts of the brain contain representations not only of the sensory systems, but also of objects such as faces. For example, so-called place cells in the hippocampus appear to play an important role in the representation of space. Each place cell represents a specific location in the environment and becomes active when its owner is at that location. Another group of neurons, grid cells, fire in a regular hexagonal pattern that is interpreted as a metric grid of the environment. This grid provides a kind of coordinate system that place cells can use for location coding.
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- Glossary
Neuron doctrine
The neuron doctrine forms the basis for our current understanding of the nervous system. According to this doctrine, the brain does not consist of a single, interconnected nerve network, but rather of individual nerve cells that communicate with each other via contact points. This was discovered by the Spanish Ramon y Cajal at the end of the 19th century when he stained nerve cell preparations from chickens and mammals. He used a staining technique developed by Camillo Golgi. For their achievement, the two researchers – who were unfortunately at odds with each other – were awarded the Nobel Prize in Medicine in 1906.
