Introduction to psychology/Key words for chapter three

This is a list of jargon for psychology. There is a short statement about what the term is and possibly a link to wipedia or wiktionary.

Action Potential

 * A signal passing through a neuron is considered an action potential.

Afferent

 * In the nervous system, afferent neurons--otherwise known as sensory or receptor neurons--carry nerve impulses from receptors or sense organs toward the central nervous system.

All-or-none principle

 * Theory that once a signal is started that it will always travel the length of a neuron at a fixed intensity, not getting stronger or weaker.

Amygdala

 * The part of the limbic with a primary role in the processing and memory of emotional reactions.

Autonomic nervous system

 * The part of the peripheral nervous system that controls the function of many glands and smooth-muscle organs.
 * It is divided into the sympathetic and parasympathetic systems.

Axon

 * The single long fiber extending from the cell body of a neuron; carries the signal to the synapse

Saltatory conduction
cell body aka Soma

Central nervous system (CNS)

 * The brain and the spinal cord.

Cerebellum

 * Region of the brain that plays an important role in the integration of sensory perception and motor output.

Cerebrum

 * The cerebrum deals with language and communication, movement, olfaction (smelling), memory formation, and emotion.

Computed tomography

 * A medical imaging method employing tomography where digital geometry processing is used to generate a three-dimensional image of the internals of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation.
 * Helps reveal structural abnormalities.

Corpus callosum

 * The corpus callosum connects the left and right cerebral hemispheres.
 * Most (but certainly not all) communication between regions in different halves of the brain are carried over the corpus callosum.

Cortex

 * The outer layer of the cerebral hemispheres; controls complex cognitive processes.

Cortical lobes

 * Four arbitirarily deignated divisions of the cortex.

Dendrite

 * The recieving portion of a neuron

Depolarization

 * A process that the nueron goes through after the passage of an action potential.
 * Depolarization is when a cell is moving farther away from 0mV while hyperpolarization is when the cell is moving closer to 0mV.

Efferent

 * In the nervous system, efferent nerves – otherwise known as motor or effector neurons – carry nerve impulses away from the central nervous system to effectors such as muscles or glands.

Neurotransmitter

 * Neurotransmitters are used to relay, amplify and modulate electrical signals between a neuron and another cell.
 * Amino acids are an example of a neurotransmitter.

Neuron

 * The basic unit of the nervous system. It is composed of a soma, dendrite, and axon.

Nodes of Ranvier

 * Nodes of Ranvier are regularly spaced gaps in the myelin sheath around an axon or nerve fiber.

Organelle

 * An organelle is a discrete structure of a cell having specialized functions.

Refractory phase

 * After the action potential the refractory phase marks a period where the neuron is less excitable.

Synapse

 * Synapses, or chemical synapses, are specialized junctions through which cells of the nervous system signal to one another and to non-neuronal cells such as muscles or glands.

Synaptic vesicle
In a neuron, synaptic vesicles, also called neurotransmitter vesicles, store the various neurotransmitters that are released during calcium-regulated exocytosis at the presynaptic terminal into the synaptic cleft of a synapse.