Chapter 2 - Behavioral Neuroscience breedlove

neuron

The basic unit of the nervous system , each composed of a cell body, receptive extension, and transmitting extension

glial cells

Nonneuronal brain cells that provide structural, nutritional, and other types of support to the brain.

neuron doctrine

The hypothesis that the brain is composed of separate cells that are distinct from others and connect to each other through contact points.

Synapse

The tiny gap between neurons where information is passed from one. to the other

Cell nucleus

Center of a cell that contains chromosomes

dendrite

one of the extensions of the cell body that are receptive surfaces of the neuron

input zone

The part of a neuron that receives information from other neurons or from specialized sensory structures. Corresponds to dendrites

Cell Body/soma

The region that is defined by the presence of a nucleus

Axon

single extension from the nerve cell that carries action potentials from the cell body to other neurons

Conduction zone

The part of the neuron over which the nerve's electrical signal may be actively propagated. Usually corresponds to the cell's axon.

Axon collateral

a branch of an axon from a single neuron

Output zone

The part of a neuron, usually corresponding to axon terminal, which cell sends information to other cells

Axon terminal

(synaptic bouton) The end of an axon or axon collateral that forms a synapse with other neuron

Multipolar neuron

A nerve cell that has many dendrites and a single axon

Bipolar neuron

a nerve cell that has a single dendrite at one end and a single axon at the other end

unipolar neuron

a nerve cell with a single branch that leaves the cell body and then extends in two directions; one end is the input zone, and the other end is the output zone

motor neuron

A nerce cell that transmits motor messages, stimulating a muscle or gland

Sensory neuron

A neuron that is directly affected by changes in the environment, such as light, odor, or touch.

Interneuron

a neuron that is neither a sensory neuron nor a motor neuron; it receives input from and sends output to other neurons

Presynpatic

The region of a synapse that releases neurotransmitter

Postsynaptic

referring to the region of a synapse that receives and responds to neurotransmitter

presynaptic membrane

the specialized membrane of the axon terminal of the neuron that transmits information by releasing neurotransmitter

synaptic cleft

The space between the presynaptic and postsynaptic elements

Postsynaptic membrane

The specialized membrane on the surface of the cell that receives information by responding to neurotransmitter from a presynaptic neuron.

Neurotransmitter

The chemical that is released from the presynaptic axon terminal that serves as basis of communication between neurons

axon hillock

a cone-shaped area from which the axon originates out of the cell body. Functionally, the integration zone of neuron

Innervate

To receive neural input

astrocyte

A star-shaped glial cell with numerous processes that run in all directions

microglial cells

extremely small glial cells that remove cellular debris from injured or dead cells

oligodendrocyte

A type of glial cells that forms myelin in the central nervous system

schwaan cell

The glial cell that forms myelin in the peripheral nervous system

myelination

The process of myelin formation

nodes of ranvier

A gap between successive segments of the myelin sheath where the axon membrane is exposed.

myelin

The fatty insulation around an axon, formed by glial cells. This sheath boosts the speed at which nerve impulses are conducted.

Multiple Sclerosis

myelin sheath destruction. disruptions in nerve impulse conduction

motor nerve

a nerve that conveys neural activity to muscle tissue and causes it to contract

sensory nerve

a nerve that conveys sensory information from the periphery into the central nervous system

somatic nervous system

the part of the peripheral nervous system that controls voluntary movement of skeletal muscles

autonomic nervous system

the part of the peripheral nervous system that controls the glands and the muscles of the internal organs (such as the heart). Its sympathetic division arouses; its parasympathetic division calms.

dorsal root

The branch of a spinal nerve, entering the dorsal horn of the spinal cord, that carries sensory information from the peripheral nervous system to the spinal cord.

ventral root

the branch of a spinal nerve, arising from the ventral horn of the spinal cord, that carries motor messages from the spinal cord to the peripheral nervous system

preganglionic

Literally, "before the ganglion." Referring to neurons in the autonomic nervous system that run from the central nervous system to the autonomic ganglia.

postganglionic

Literally, "after the ganglion." Referring to neurons in the autonomic nervous system that run from the autonomic ganglia to various targets in the body.

sympathetic nervous system

a component of the autonomic nervous system that arises from the thoracic and lumbar spinal cord

parasympathetic nervous system

a component of the autonomic nervous system that arises from both the cranial nerves and the sacral spinal cord

Norepinephrine

A neurotransmitter produced and released by sympathetic postganglionic neurons to accelerate organ activity.

Acetylcholine

A neurotransmitter produced and released by parasympathetic postganglionic neurons, by motoneurons, and by neurons throughout the brain.

cerebral cortex

The outer covering of the cerebral hemispheres that consists largely of neuronal cell bodies and their branches

sylvian fissure

a deep fissure that demarcates the temporal lobe

corpus callosum

the large band of neural fibers connecting the two brain hemispheres and carrying messages between them

gray matter

areas of the brain that are dominated by cell bodies that are devoid of myelin

white matter

a pale-colored layer underneath the cortex that consists largely of axons with white myelin sheaths

meninges

The three protective sheers of tissue that surround the brain and spinal cord

CSF

cerebrospinal fluid, the fluid that fills the brain ventricles

ventricular system

a system of fluid-filled cavities inside the brain

lateral ventricle

A complexly shaped lateral portion of the ventricular system within each hemisphere of the brain.

choroid plexus

A highly vascular portion of the lining of the ventricles that secretes cerebrospinal fluid.

circle of Willis

A structure at the base of the brain that is formed by the joining of the carotid and basilar arteries.

blood-brain barrier

The mechanisms that make the movement of substances from blood vessels into brain cells more difficult than exchanges in other body organs, affording the brain greater protection from exposure to some substances found in the blood