Ch 3 Anatomy of the Nervous System Flashcards
Columnar Organization
The functional organization of the neocortex in vertical columns; the cells in each column form a mini-circuit that performs a single function
Metencephalon
One of the five major divisions of the brain; it includes the pons and cerebellum.
Meninges
The three protective membranes that cover the brain and spinal cord (singular meninx).
Cranial Nerves
The 12 pairs of nerves extending from the brain (e.g., the optic nerves, the olfactory nerves, and the vagus nerves).
Fissures
The large furrows in a convoluted cortex. Which partially divide the brain into 4 lobes
Caudate
The tail-like structure that is part of the striatum.
Tracts
Bundles of axons in the central nervous system.
Multipolar neuron
A neuron with more than two processes extending from its cell body.
Superior Temporal Gyri
The plural of superior temporal gyrus. Sitting in the temporal lobe
Substantia Nigra
The midbrain nucleus whose neurons project via the nigrostriatal pathway to the striatum of the basal ganglia; it is part of the mesotelencephalic dopamine system. Parkinson’s disease, a disorder characterized by rigidity, tremors, and poverty of voluntary movement, is associated with the deterioration of this pathway
Medial
Toward the midline of the body
Distal
Far from something, far from the CNS
Horizontal Sections
Any slices of brain tissue cut in a plane that is parallel to the top of the brain.
Diencephalon
One of the five major divisions of the brain; it is composed of the thalamus and hypothalamus.
Parietal Lobe
One of the four cerebral lobes; it is located just posterior to the central fissure. postcentral gyrus analyzes sensations from the body (e.g., touch), whereas the remaining areas of cortex in the posterior parts of the parietal lobes play roles in perceiving the location of both objects and our own bodies and in directing our attention. touch taste and temperature
Cross Section
Section cut at a right angle to any long, narrow structure of the CNS. such as the spinal cord
Parasympathetic nerves
Those autonomic motor nerves that project from the brain to the sacral region of the spinal cord. neurons that project from the CNS synapse near their target organs on very short second-stage neurons and conserve energy
Microglia
Glial cells that respond to injury or disease by engulfing cellular debris and triggering inflammatory responses.
Corpus callosum
The largest cerebral commissure. connecting the left and right cerebral hemispheres.
Posterior
Toward the tail end of a vertebrate or toward the back of the head.
Frontal Lobe
The most anterior of the four cerebral lobes. has two distinct functional areas: The precentral gyrus and adjacent frontal cortex have a motor function, whereas the frontal cortex anterior to motor cortex performs complex cognitive functions, such as planning response sequences, evaluating the outcomes of potential patterns of behavior, and assessing the significance of the behavior of others
Gyri
The cortical ridges that are located between fissures or sulci. Bumps
Amygdala
A structure in the anterior temporal lobe, just anterior to the hippocampus; plays a role in emotion.
Blood-Brain Barrier
The mechanism that impedes the passage of toxic substances from the blood into the brain.
Brain Stem
The part of the brain on which the cerebral hemispheres rest; in general, it regulates reflex activities that are critical for survival (e.g., heart rate and respiration).
Occipital Lobe
The most posterior of the four cerebral lobes; its function is primarily visual.
Astrocytes
Large, star-shaped glial cells that play multiple roles in the CNS. to exchange chemical signals with neurons and other astrocytes, to control the establishment and maintenance of synapses between neurons, to modulate neural activity, to form functional networks with neurons and other astrocytes, to control the blood–brain barrier, and to respond to brain injury
Dorsal
Toward the surface of the back of a vertebrate or toward the top of the head.
Choroid Plexuses
The networks of capillaries that protrude into the ventricles from the pia mater and produce cerebrospinal fluid.
Hippocampus
A structure of the medial temporal lobes that plays a role in various forms of memory.
Stellate Cells
Small star-shaped cortical interneurons.
Cerebrospinal fluid (CSF)
The fluid that fills the subarachnoid space, the central canal, and the cerebral ventricles. primary function of CSF is to cushion the brain within the skull and serve as a shock absorber for the central nervous system, CSF also circulates nutrients and chemicals filtered from the blood and removes waste products from the brain.
Cerebral commissures
largest cerebral commissure, the corpus callosum, Cerebral commissures
Tracts that connect the left and right cerebral hemispheres.
Hypothalamus
The diencephalic structure that sits just below the anterior portion of the thalamus. is involved in a variety of motivated behaviors such as eating, sleep, and sexual behavior.
Nerves
Bundles of axons in the peripheral nervous system.
Ipsilateral
On the same side of the body.
Pituitary gland
The gland that dangles from, and is controlled by, the hypothalamus. pituitary gland is called the ‘master gland’ as the hormones it produces control so many different processes in the body.
Contralateral
Projecting from one side of the body to the other.
Sagittal sections
Any slices of brain tissue cut in a plane that is parallel to the side of the brain.
Tectum
The “roof,” or dorsal surface, of the mesencephalon; it includes the superior and inferior colliculi.
Glial cells
Several classes of nonneural cells of the nervous system.
They maintain homeostasis, form myelin, and provide support and protection for neurons.
Neurons
Cells of the nervous system that are specialized for the reception, conduction, and transmission of electrochemical signals.
Ventral posterior nucleus
A thalamic relay nucleus in both the somatosensory and gustatory systems.
Pyramidal Cells
Large multipolar cortical neurons with a pyramid-shaped cell body, an apical dendrite, and a very long axon.
Interneurons
Neurons with short axons or no axons at all, whose function is to integrate neural activity within a single brain structure, not to conduct signals from one structure to another.
Dorsal root ganglia
Structures just outside the spinal cord that are composed of the cell bodies of dorsal root axons.
Nuclei
The DNA-containing structures of cells; also, clusters of neuronal cell bodies in the central nervous system (singular nucleus).
Septum
A midline nucleus of the limbic system, located near the anterior tip of the cingulate cortex.
Tegmentum
The ventral division of the mesencephalon; it includes part of the reticular system, substantia nigra, and red nucleus.
Nissl Stain
A neural stain that has an affinity for structures in neuron cell bodies. Cresyl violet and other Nissl dyes penetrate all cells on a slide, but they bind effectively only to structures in neuron cell bodies. Thus, they often are used to estimate the number of cell bodies in an area, by counting the number of Nissl-stained dots.
Arachnoid membrane
The meninx that is located between the dura mater and the pia mater and has the appearance of a gauzelike spiderweb.
Cerebral cortex
The layer of neural tissue covering the cerebral hemispheres of humans and other mammals.
Cerebellum
A metencephalic structure that is thought to participate in the storage of memories of learned sensorimotor skills.
Neocortex
Six-layered cerebral cortex of relatively recent evolution; it constitutes 90 percent of human cerebral cortex.
Dorsal horns
The two dorsal arms of the spinal gray matter.
Sulci
Small furrows in a convoluted cortex
Inferior Colliculi
The structures of the tectum that receive auditory input from the superior olives.
Decussate
To cross over to the other side of the brain.
Cingulate gyri
Large gyri located on the medial surfaces of the frontal lobes, just superior to the corpus callosum.
Postcentral gyrus
The gyrus located just posterior to the central fissure; its function is primarily somatosensory.
Central fissure
The large fissure that separates the frontal lobe from the parietal lobe.
Superior colliculi
Two of the four nuclei that compose the tectum; they receive major visual input.
Electron microscopy
A microscopy technique used to study the fine details of cellular structure.
Lateral geniculate nuclei
The six-layered thalamic structures that receive input from the retinas and transmit their output to the primary visual cortex.
Efferent nerves
Nerves that carry motor signals from the central nervous system to the skeletal muscles or internal organs.
Somatic nervous system (SNS)
The part of the peripheral nervous system that interacts with the external environment.
Lateral
Away from the midline of the body of a vertebrate, toward the body’s lateral surfaces.
Cingulate cortex
The cortex of the cingulate gyri, which are located on the medial surfaces of the frontal lobes.
Peripheral nervous system (PNS)
The portion of the nervous system outside the skull and spine.
Autonomic nervous system (ANS)
The part of the peripheral nervous system that participates in the regulation of the body’s internal environment.
Longitudinal fissure
the large fissure that separates the two cerebral hemispheres.
striatum
A structure of the basal ganglia that is the terminal of the dopaminergic nigrostriatal pathway.
Basal Ganglia
A collection of subcortical nuclei (e.g., striatum and globus pallidus). responsible primarily for motor control, as well as other roles such as motor learning, executive functions and behaviors, and emotions.
Superior
Toward the top of the primate head.
Subarachnoid space
The space beneath the arachnoid membrane, which contains many large blood vessels and cerebrospinal fluid.
Pons
The metencephalic structure that creates a bulge on the ventral surface of the brain stem. regulation of functions carried out by the cranial nerves it houses, works together with the medulla oblongata to serve an especially critical role in generating the respiratory rhythm of breathing.
Reticular formation
A complex network of about 100 tiny nuclei that occupies the central core of the brain stem. involved in a variety of functions—including sleep, attention, movement, the maintenance of muscle tone, and various cardiac, circulatory, and respiratory reflexes.
Proximal
Close to something.
Golgi stain
A neural stain that completely darkens a few of the neurons in each slice of tissue, thereby revealing their silhouettes.
Ganglia
Clusters of neuronal cell bodies in the peripheral nervous system (singular ganglion).
Myelencephalon
The most posterior of the five major divisions of the brain; the medulla.
Pia Mater
The delicate, innermost meninx.
Massa intermedia
The neural structure located in the third ventricle that connects the two lobes of the thalamus.
Ventral
Toward the chest surface of a vertebrate or toward the bottom of the head.
Central nervous system (CNS)
The portion of the nervous system within the skull and spine.
Oligodendrocytes
Glial cells that myelinate axons of the central nervous system; also known as oligodendroglia. wrap around the axons of some neurons of the central nervous system. These extensions are rich in myelin, a fatty insulating substance, and the myelin sheaths they form increase the speed and efficiency of axonal conduction.
Unipolar Neurons
A neuron with one process extending from its cell body.
Myelin sheaths
Coverings on the axons of some neurons that are rich in myelin and increase the speed and efficiency of axonal conduction.
Limbic system
A collection of interconnected nuclei and tracts that ring the thalamus. is involved in the regulation of motivated behaviors—including the four F’s of motivation: fleeing, feeding, fighting, and sexual behavior.
Afferent nerves
Nerves that carry sensory signals to the central nervous system.
Lateral fissure
The large fissure that separates the temporal lobe from the frontal lobe.
Globus pallidus
A sructure of the basal ganglia that is located between the putamen and thalamus.
Telencephalon
The most superior of the brain’s five major divisions. mediates the brain’s most complex functions. It initiates voluntary movement, interprets sensory input, and mediates complex cognitive processes such as learning, speaking, and problem solving.
Inferior
Toward the bottom of the primate head or brain.
Red nucleus
A structure of the sensorimotor system that is located in the tegmentum of the mesencephalon.
Bipolar neuron
A neuron with two processes extending from its cell body.
Thalamus
The large two-lobed diencephalic structure that constitutes the anterior end of the brain stem; many of its nuclei are sensory relay nuclei that project to the cortex.
relaying sensory and motor signals, as well as regulation of consciousness and alertness.
Fornix
The major tract of the limbic system; it connects the hippocampus with the septum and mammillary bodies.
Mesencephalon
One of the five major divisions of the brain; it is composed of the tectum and tegmentum.
Dura mater
The tough outer meninx.
Schwann cells
The glial cells that compose the myelin sheaths of PNS axons and promote the regeneration of PNS axons.
Medial geniculate nuclei
The auditory thalamic nuclei that receive input from the inferior colliculi and project to primary auditory cortex.
Mammillary bodies
The pair of spherical nuclei that are located on the inferior surface of the hypothalamus.
Central Canal
The small CSF-filled channel that runs the length of the spinal cord.
Cerebral aqueduct
A narrow channel that connects the third and fourth ventricles.
Optic chiasm
The X-shaped structure on the inferior surface of the diencephalon; the point where the optic nerves decussate.
Anterior
Toward the nose end of a vertebrate.
Cerebral ventricles
The four CSF-filled internal chambers of the brain: the two lateral ventricles, the third ventricle, and the fourth ventricle.
White Matter
Portions of the nervous system that are white because they are composed largely of myelinated axons.
Sympathetic nerves
Those motor nerves of the autonomic nervous system that project from the CNS in the lumbar and thoracic region areas of the spinal cord. stimulate, organize, and mobilize energy resources in threatening situations,project from the CNS synapse on second-stage neurons at a substantial distance from their target organs
temporal lobe
One of the four major cerebral lobes; it lies adjacent to the temples and contains the hippocampus and amygdala.
is related to the perception of auditory, taste, olfactory sensations, analysis and synthesis of speech sounds, memory mechanisms.
ventral horns
The two ventral arms of the spinal gray matter.
Frontal section
Any slices of brain tissue cut in a plane that is parallel to the face; also termed coronal sections.
Putamen
A structure that is joined to the caudate by a series of fiber bridges; together the putamen and caudate compose the striatum.
Precentral gyrus
The gyrus located just anterior to the central fissure; its function is primarily motor.
Myelin
A fatty insulating substance.
Periaqueductal gray (PAG)
The gray matter around the cerebral aqueduct, which contains opiate receptors and activates a descending analgesia circuit. one of the structures of the tegmentum
Sensory relay nuclei
Those nuclei of the thalamus whose main function is to relay sensory signals to the appropriate areas of cortex.
Gray Matter
Portions of the nervous system that are gray because they are composed largely of cell bodies and unmyelinated interneurons.
