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- Glossary
Epiphysis
The epiphysis (pineal gland) is an unpaired component of the epithalamus (part of the diencephalon). It is a gland that secretes melatonin. Among other things, the epiphysis controls the "internal clock."
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- Glossary
Episodic memory
Episodic memory is a form of declarative long-term memory. It includes one's own biography, i.e., important experiences and events from the past, including their location in space and time, as well as the feeling of having had the experience oneself.
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- Glossary
Epithalamus
A part of the diencephalon (midbrain) located behind the thalamus (the largest part of the midbrain). It includes the habenulae and the epiphysis, among other structures.
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- Glossary
Threshold potential
In order for an action potential to be triggered, the membrane potential at the axon hillock of a neuron must exceed the threshold value of approximately –50 mV (relative to the resting potential of –70 mV). This is the threshold potential. If the depolarization remains below this threshold, no action potential is triggered.
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- Glossary
Executive functions
Brain research uses the term "executive functions" to describe the "higher" mental abilities of living beings. These include, for example, focused attention, planning actions, error correction, decision-making, impulse control, and emotional regulation.
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- Glossary
Extinction
In extinction, a previously conditioned stimulus is presented several times without the originally paired reinforcement until the conditioned response subsides. For example, a dog has learned that the ringing of a bell announces food (conditioned stimulus → conditioned salivation response). In extinction, the bell is now rung several times without food following. After a few repetitions, the dog stops drooling when the bell rings: the conditioned response subsides. This decrease in response can also be detected at the synaptic level, for example, by a reduction in neurotransmitter release.
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- Glossary
Extrapyramidal system
The extrapyramidal system refers to a series of structures in the brain that play a key role in influencing motor function but are not part of the pyramidal tract. It consists of multisynaptic neuron chains. The extrapyramidal system includes numerous nuclei such as the striatum, pallidum, nucleus ruber, and substantia nigra.
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- Glossary
excitatory
Exciting synapses are described as excitatory when they depolarize the subsequent cell membrane and can thus lead to the formation of an action potential. An excitatory effect is usually produced by an exciting transmitter (messenger substance), such as glutamate. The opposite is an inhibitory synapse.
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- Glossary
Color blindness
The inability to perceive colors. Instead, those affected only see brightness. This can be caused by hereditary cone blindness or a retinal disease, for example, but also by damage to the optic nerves or visual association areas.
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- Glossary
Color consistency
A correction mechanism that ensures the relatively constant appearance of an object's color under different lighting conditions. This means that the red of a rose appears the same in the morning as it does in the evening, even though the light changes depending on the time of day and weather conditions.
