Chapter 2 Flashcards
Neuron or Nerve Cells
Basic Unit of the nervous system, which is composed of dendrites, an integrating cell body, an axon, and an axon terminal.
Glial Cells or Glia Cells
Nonneuronal brain cells that provide structural, nutritional, and other types of support to the brain.
Synapse
The cellular location where information is transmitted from a neuron to another cell.
Input Zone
Where the neuron collects and processes information from the environment or other cells.
Integration Zone
Where the neuron decides if necessary to produce a neural signal.
Conduction Zone
The area of the neuron where information can be electrically transmitted over great distances.
Output Zone
Where the neuron transfers information to other cells.
Dendrites
Extensions coming off the cell body of a neuron, where information is received. This is the main area that the input zone takes place.
Cell Body or Soma
The region of a neuron where the cell nucleus is. This is where the integration zone takes place.
Axon or Nerve Fiber
A single extension from nerve cells that carries action potentials (the information) from the cell body to the axon terminals. This is where the conduction zone takes place.
Axon Collateral
A branch of an axon.
Axon Terminal or Synaptic Bouton
The end of an axon or axon collateral which forms a synapse onto either another neuron or other cell to transfer the information to. This is where the output zone occurs.
Motor Neurons or Motoneuron
A neuron that transmits neural messages to muscles or glands. Motor Neurons are often very long.
Sensory Neurons
These nerve cells gather sensory information, like light, touch, smell, etc.
Interneurons
A nerve cell that receives inputs from nerve cells and then outputs to other nerve cells. An interneuron allows the sensory neurons to send information to motor neurons. Also interneurons can communicate between each other.
Multipolar Neurons
A nerve cell that has many dendrites extending from the soma. It also has just a single axon, so no axon collateral.
Bipolar Neurons
A nerve cell that has a single dendrite extending from the soma. It has just a single axon, so no axon collateral.
Unipolar Neurons
A nerve cell that has a single branch that extends in two directions. This branch serves as the dendrite and the axon.
Presynaptic Neuron
The neuron that will be transferring information. Presynaptic means located on the transmitting side of a synapse.
Postsynaptic Neuron
The neuron that will be receiving information.
Presynaptic Membrane
The membrane on the axon terminal of a nerve cell that transmits information by releasing a neurotransmitter.
Postsynaptic Membrane
The membrane on the surface of a neuron that receives information by responding to the neurotransmitter from a presynaptic neuron.
Synaptic cleft
The space between the presynaptic and postsynaptic neurons at a synapse.
Synaptic vesicle
A small, spherical structure that contains molecules of the neurotransmitter.
Neurotransmitter or Synaptic transmitter
The chemical released from the presynaptic axon terminal that serves a the basis of communication between neurons.
Neurotransmitter Receptor
A protein that selectively senses and reacts to molecules of a corresponding neurotransmitter or hormone.
Neuroplasticity
The ability of the nervous system to change in response to an experience or the environment.
Axon hillock
The cone shaped are on the cell body from which the axon originates.
Innervate
To provide neural input. (supply with nerves)
axonal transport
The transportation of materials from the neuronal cell body toward the axon terminals back toward the cell body.
Oligodendrocyte
Type of glial cell that forms myelin in the central nervous system. The myelin sheaths cover the axons on neurons.
Schwann Cell
A type of glial cells that form myelin in the peripheral nervous system.
Myelin
A fatty insulation around an axon, formed by glial cells. This sheath boosts speed at which nerve impulses are conducted.
Node of Ranvier
A gap between the successive segments of myelin sheaths where the axon terminal is exposed.
Astrocyte
Star shaped glial cell that is responsible for helping define the structure of the brain and help control blood flow depending on where the brain is active the most.
Microglial cells
Small motile cells that remove cellular debris from injured or dead cells. Also they have recently been found to also be involved in pain perception.
Edema
General term referring to swelling of any body tissue, including the brain.
Gross anatomy
Anatomical features of the nervous system that are apparent to the naked eye.
Central Nervous System (CNS)
The portion of the nervous system that includes the brain and spinal cord.
Peripheral Nervous System (PNS)
The portion of the nervous system that includes all the nerves and neurons outside the brain and spinal cord.
Nerve
A collection of axons bundled together outside the central nervous system.
Motor Nerve
A nerve that transmits information from the central nervous system to the muscles and glands.
Sensory Nerve
A nerve that conveys information from the body to the central nervous system.
Somatic Nervous System
A part of the peripheral nervous system that supplies neural connections mostly to the skeletal muscles and sensory systems of the body. It consists of cranial nerves and spinal nerves.
Autonomic Nervous System
A part of the peripheral nervous system that provides the main neural connections to the internal organs.
Cranial Nerve
A nerve that is connected directly to the brain.
Spinal Nerve
A nerve that emerges from the spinal cord.
Cervical
Refers to the topmost eight segments of the spinal cord, it is in the neck region.
Thoracic
Referring to the 12 spinal segments below the cervical portion of the spinal cord, this is in the torso region.
Lumbar
Referring to the five spinal segments in the upper part of the lower back.
Sacral
Referring to the five spinal segments in the lower part of the lower back.
Coccygeal
The lowest spinal vertebrae also know as the coccyx.
Sympathetic Nervous System
The part of the autonomic nervous system that generally prepares the body for action.
Parasympathetic Nervous System
The part of the autonomic nervous system that generally prepares the body to relax and recuperate.
Cerebral Hemispheres
The two halves of the forebrain, often referred to as the left and right sides of the brain.
Cerebral Cortex
The outer covering of the cerebral hemispheres, which consists largely of cell bodies and their branches.
Gyrus
A ridged or raised portion of a convoluted brain surface.
Sulcus
A crevice or valley of a convoluted brain surface.
Frontal Lobe
The most anterior portion of the cerebral cortex.
Parietal Lobe
The large region of the brain that is lying between the frontal and occipital lobes. It is in both cerebral hemispheres.
Temporal Lobe
The large lateral region of the cortex in both cerebral hemispheres. It is continuous with the parietal lobe posteriorly and separated from the frontal lobe with the Sylvian fissure.
Occipital Loba
The large region of cortex that covers much of the posterior part of each hemisphere.
Sylvian Fissure or the Lateral Sulcus
A deep fissure that demarcates the temporal lobe.
Central Sulcus
A fissure that divides the frontal lobe from the parietal lobe.
Corpus Callosum
The main band of axons that connect the two hemispheres, so they can communicate.
Postcentral Gyrus
The strip of parietal cortex, just posterior to the central sulcus, this receives somatosensory information from the entire body.
Precentral Gyrus
The strip of frontal cortex, just anterior to the central sulcus, that is crucial for moto control.
Gray Matter
Areas of the brain that are dominated by cell bodies and are devoid of myelin. Gray matter mainly receives and processes information.
White Matter
A light colored layer of tissue, consisting mostly of myelin-sheathed axons. This lies under the gray matter of the cortex. White matter mainly transmits information.
Neural Tube
An embryonic structure with subdivisions that correspond to the future forebrain, midbrain, and hindbrain.
Forebrain
The frontal division of the neural tube, this contain the central hemispheres, the thalamus and hypothalamus.
Midbrain
The middle division of the brain.
Hindbrain
The rear division of the brain, which will contain the cerebellum, pons, and medulla.
Telencephalon
The anterior part of the fetal forebrain, which will become the cerebral hemispheres in the adult brain.
Diencephalon
The posterior part of the fetal forebrain, which will become the thalamus and hypothalamus in the adult brain.
Brainstem
Region of the brain that consists of the midbrain, the pons, and the medulla.
Nucleus
A collection of neuronal cell bodies within the central nervous system.
Tract
A bundle of axons found within the central nervous system.
Pyramidal Cell
A large nerve cell that has roughly a pyramid shaped cell body and is found in the cerebral cortex.
The most prominent neuron found in the cerebral cortex.
Cortical Column
One of the vertical columns that constitute the basic organization of the cerebral cortex.
Basal Ganglia
A group of forebrain nuclei, including the caudate nucleus, globus pallidus, and the putamen. This is found deep within the cerebral hemisphere.
Plays a major role in the control of movement.
Limbic System
A loosely defined, widespread group of brain nuclei that innervate each other and form a network.
Involved in emotion and learning.
Amygdala
A group of nuclei in the medial anterior part of the temporal brain.
Involved in emotion regulation and perception of odor.
Hippocampus
A medial temporal lobe structure that is important for learning and memory.
Fornix
A fiber tract that extends from the hippocampus to the mammillary body.
Cingulate Gyrus
Strip of cortex, found in the frontal and parietal midline, that is part of the limbic system and is implicated in many cognitive functions.
Olfactory Bulb
An anterior projection of the brain that terminates in the upper nasal passages and provides the primary inputs for the sense of smell.
Thalamus
Paired structures to either side of the third ventricle that direct the flow of sensory information to and from the cortex.
Hypothalamus
Part of the diencephalon, lying ventral to the thalamus.
Tectum
The dorsal portion of the midbrain, consisting of the inferior and superior colliculi.
Superior Colliculi
Involved in processing visual information.
Inferior Colliculi
Involved in processing auditory information.
Tegmentum
Main body of the midbrain, it contains the substantia nigra, periaqueductal gray, part of the reticular formation, and multiple fiber tracts.
Substantia Nigra
A brainstem structure that innervates the basal ganglia and is a major source of dopaminergic projections.
Periaqueductal Gray
A midbrain region involved in pain perception.
Reticular Formation
Extensive region of brainstem that extends from the medulla through the thalamus. It is involved in sleep and arousal.
Cerebellum
A structure located at the back of the brain. It is involved in the central regulation of movement and in some forms of learning.
Pons
Portion of the brainstem that connects the midbrain to the medulla.
Medulla
The posterior part of the hindbrain, continuous with the spinal cord. Conveys all the major motor and sensory fibers to and from the body. Also it controls respiration and heart rate.
Meninges
The three protective membranes that surround the brain. The dura mater, pia mater, and the arachnoid.
Dura Mater
The outermost meninge that surrounds the brain and spinal cord.
Pia Mater
The innermost of the three meninges that surround the brain and spinal cord.
Arachnoid
The middle meninge that surrounds the brain and spinal cord.
Cerebral Spinal Fluid (CSF)
The fluid that fills the cerebral ventricles.
Meningitis
Acute inflammation of meninges, usually caused by viral or bacterial infection.
Meningioma
A noninvasive tumor of the meninges.
Ventricular System
A system of fluid filled cavities inside the brain.
Lateral Ventricle
A C-shaped portion of the ventricular system. Both hemispheres of the brain have them. This is where Cerebral Spinal Fluid is made, with the help of the choroid plexus.
Choroid Plexus
A membrane that lines the lateral ventricles, which produces cerebral spinal fluid by filter the blood.
Third Ventricle
The midline ventricle that takes the cerebral spinal fluid from the lateral ventricles to the fourth ventricle.
Fourth Ventricle
The passageway within the pons that receives cerebral spinal fluid from the third ventricle and releases it to surround the brain and spinal cord.
Hydrocephalus
A ballooning of ventricles, at the expense of the surrounding brain, which may occur when circulation of cerebral spinal fluid is blocked.
Glymphatic System
A lymphatic system in the brain that participates in the removal of wastes and it also moves nutrients and signaling compounds.
Cerebral Arteries
The three pairs of large arteries within the skull that supply blood to the cerebral cortex.
blood-brain barrier
The mechanism that makes the movement of substances from blood vessels into brain cells more difficult than exchanges in other body organs. Helps protect the brain from exposure to potentially harmful substances in the blood. However, it can also make it difficult for helpful drugs to get to the brain.
Stroke
Damage to a region of brain tissue that results from the blockage or rupture of vessels that supply blood to that region.
Transient ischemic attack (TIA)
A temporary blood restriction to part of the brain that causes stroke-like symptoms that quickly resolve. This is a warning sign that the person would be at an elevated stroke risk.
Computerized Axial Tomography (CT or CAT)
A noninvasive technique for examining brain structure through computer analysis of x-ray absorption at several positions around the head.
Magnetic Resonance Imaging (MRI)
A noninvasive brain-imaging technology that uses magnetism and radio frequency energy to create images of the gross structure of the living brain.
Diffusion Tensor Imaging (DTI)
A modified form of MRI in which diffusion of water in confined space is exploited to produce images of axonal fiber tracts.
Functional MRI (fMRI)
Magnetic resonance imaging that detects changes in blood flow and therefor identifies region of the brain that are particularly active during a given task.
Positron Emission Tomography (PET)
A brain imaging technology that tracks metabolism of injected radioactive substances in the brain, in order to map brain activity.
Transcranial Magnetic Stimulation (TMS)
A noninvasive technique for examining brain function that applies strong magnetic fields to stimulate cortical neurons in order to identify discrete areas of the brain that are particularly active during specific behaviors.
Magnetoencephalography (MEG)
A noninvasive brain-imaging technology that create maps of brain activity during cognitive tasks by measuring tiny magnetic fields produced by active neurons.
