CNS, Ch 12 Flashcards
What are the four regions of the brain?
Cerebrum
Diencephalon
Cerebellum
Brainstem
The enlarged superior portion of the brain. Composed of two hemispheres, which each have 5 lobes. Functions?
Cerebrum
Performs higher mental functions, interprets sensory stimuli, plans and initiates movement.
The central core of the brain, beneath the cerebral hemispheres. Consists of four distinct structural parts. Functions?
Diencephalon
Processing, integrating, relaying information, homeostasis, regulation of biological rhythms.
The posterior and inferior portion of the brain, composed of right and left hemispheres. Second largest part of the brain. Functions?
Cerebellum
Planning and coordination of movement, particularly for complex activities.
The oldest part of the brain from an evolutionary standpoint. Connects the brain and spinal cord. Functions?
Brainstem
Basic involuntary homeostatic functions, control of certain reflexes, monitoring movement, integrating and relaying information
Long, tubular organ encased within and protected by the vertebral cavity. Ends between the first and second lumbar vertebrae. Has internal cavity filled with fluid that is continuous with the ventricles of the brain.
Spinal cord
Organ that resides in the cranial cavity and directly or indirectly controls most of the body’s functions. Primarily made of nervous tissue, with some epithelial and connective. Internal ventricles, 20% of total blood flow during rest.
The brain
The white matter in what is superficial? Where is it deep?
Superficial in the spine
Deep in the cerebrum
White matter that receives input and sends output from the gray matter in the cerebrum. Shuttles information to and from the brain in the spinal cord.
Tracts
Clusters of cell bodies and dendrites in the cerebral gray matter. Contains this that processes information in the spinal cord.
Nuclei
Shallow grooves and the elevated ridges between them in the cerebrum that increase the surface area of the brain and make it more compact?
Deep grooves?
Sulcus
Gyri
Fissures
The anteriormost lobe of each cerebral hemisphere. The neurons are responsible for planning and executing movement and complex mental functions.
Frontal lobes
The posterior boundary of the frontal lobes?
What is just anterior to this boundary?
Central sulcus
Precentral gyrus
Posterior to the frontal lobes in the cerebrum. Processing and integrating sensory information and function in attention.
What is the major gyrus of each, that sits just posterior to the central sulcus?
Parietal lobes
Postcentral gyrus
On the lateral surfaces of the cerebral hemisphere, separated from the frontal and parietal lobes by what?
Related to hearing, language, memory, and emotions.
Temporal lobes
Lateral fissure
The posterior lobe of each cerebral hemisphere, separated from the parietal by what?
Process all info related to vision.
Occipital lobes
Parieto-occipital sulcus
Lobes that are visible only when the lateral fissure is opened.
Taste and viscera.
Insulas
Functionally the most complex region of the brain, made of gray matter. Covers the cerebral hemispheres like bark on a tree. The majority is neocortex. Only contains interneurons.
Cerebral cortex
Part of the cerebral cortex. Conscious processes. Allows us to become aware of and respond to our surroundings. Long division type processes.
Neocortex
Three areas of the neocortex and what they do?
Primary motor cortex-plans and executes movement
Primary sensory cortices-first to receive and process sensory info
Association-integrates different types of info. Most of the neocortex
Two main areas of the cerebral cortex that deal with temp and touch. The first is located in the postcentral gyrus of the parietal lobe. The second is posterior to the first.
Somatosensory cortices
Primary somatosensory cortex (S1)
Somatosensory association cortex (S2)
The first area to receive visual input, lying at the posterior end of the occipital lobed. It feeds information into the surrounding this, which process color, object movement, and depth.
Primary visual cortex
Visual association areas
Located in the superior temporal lobe, and the first to receive auditory information. From here information travels to this adjacent section, as well as other multimodal areas like it.
Primary auditory cortex
Auditory association cortex
Appearing to be in the insula and part of the parietal lobe. Taste information.
Information pertaining to equilibrium and positioning.
Consists of several areas in the lambic lobes and medial temporal, sense of smell.
Gustatory cortex
Vestibular areas
Olfactory cortex
These of each cerebral hemisphere control the motor activity of the opposite side of the body via neurons of the PNS called this.
Upper motor neurons
Lower motor neurons
Association area that integrates one specific type of information only, which generally relates to perception.
Unimodal association area
Association area that integrates information from multiple different sources and appear to carry out many higher mental functions.
Multimodal association area
A type of white matter that connects the left and right cerebral hemispheres. Of the four groups of these, this one is the largest, which sits at the middle of the brain at the base of the longitudinal fissure.
Commissural fibers
Corpus callosum
White matter that connects the cerebral cortex of one hemisphere with other areas of the same hemisphere, as well as with other parts of the brain and the spinal cord. Form a radiating pattern called what?
Projection fibers
Corona radiata
The projection fibers that condense around the diencephalon on the right and left sides to form two V-shaped bands known as what?
Internal capsules
White matter restricted to a single hemisphere. Connects gray matter of cortical gyri with one another.
Association fibers
System of the brain that is found only in mammals and participates in learning, memory, emotion, and behavior. Mediates the responses of the viscera to certain situations. Composed of these four parts plus the pathways that connect them with each other and other parts of the brain.
Limbic system Cingulate gyrus Parahippocampal gyrus Hippocampus (fornix) Amygdala
Found at the physical center of the brain. Has four components which are?
Diencephalon Thalamus Epithalamus Hypothalamus Subthalamus
Receives incoming information, processes and integrates it, and the sends it to specific motor or sensory areas of the cerebral cortex. Some receive only sensory or only motor.
Specific relay nuclei
In the thalamus
Makes up about 80% of the diencephalon. Between its two masses lies the third ventricle. Has three main groups of nuclei which receive input from multiple sources. Controls info entry into cerebral cortex. Edits, sorts, routes stimuli.
Thalamus
Receives input from many sources indirectly via other thalamic nuclei or directly from other parts of the brain. Process info related to emotions, memory, and integration of sensory info. Send it to association areas of cortex.
Association nuclei
In the thalamus
Receive info from other basal nuclei, the cerebellum, and motor cortex. Send it to broad areas of the cortex and the rest of the brain. Controlling arousal, consciousness, and the level of excitability of the cerebral cortex.
Nonspecific nuclei
In the thalamus
A collection of nuclei that sits anterior and inferior to the thalamus. Less than 1% of mass of brain. Regulars much of autonomic, the sleep/wake cycle, thirst, hunger, temp.
Hypothalamus
Endocrine organ attached to the inferior portion of the hypothalamus by an extension, the infundibulum. Controlled by hypothalamus, secretes hormones that influence other endocrine glands.
Pituitary gland
Two hormones produced by the hypothalamus that do not act on the pituitary gland. One influences water balance in the body. Other stimulates contraction of the uterus during birth and promotes emotional bonding.
Antidiuretic hormone (ADH) Oxytocin
Two small projections connecting the limbic system and the hypothalamus. Receive input from the hippocampus with which they play a role in regulating memory and behavior.
Mammillary bodies
Endocrine glad that is the major part of the epithalamus, at the posterosuperior portion of the diencephalon. Secretes melatonin, regulating the sleep/wake cycle. Pine cone.
Pineal gland
Makes up the posterior and inferior portion of the brain. Helps in coordination of movement. Composed of two hemispheres connected by vermis. Folia ridges.
Cerebellum, made of
Anterior lobe
Posterior lobe
Flocculonodular lobe
White matter in cerebellum that converges into three tracts that connects the cerebellum to the brainstem, forming the only route by which info flows into and out of the cerebellum.
Cerebellar peduncles
Controls many basic homeostatic functions, , numerous reflexes, functions in movement, sensation, and maintaining alertness. Contains fourth ventricle, which is continuos with the central canal of the spinal cord.
Brainstem
The brainstem has three subdivisions. What are they and what do they contain?
Superior midbrain, middle pons, inferior medulla oblongata.
Fibers of the cerebellum and related nuclei
Nuclei of the reticular formation
Tracts of white matter between the spinal cord and brain
Cranial nerve nuceli
The inferiormost portion of the brain stem, which blends with the spinal cord after it passes the foramen magnum. Contains tracts of white matter involved in movement and sensation. Regulates many homeostatic functions.
Medulla oblongata
Has elevated ridges, pyramids, which contain upper motor neuron fibers of the corticospinal tract.
Within pyramids, most fibers of the right and left corticospinal tracts crossed switch sides, after which they descend through the spinal cord. Switching is?
Decussate
Functions of the hypothalamus?
Regulates the autonomic NS Regulates sleep/wake cycle Regulates thirst and hunger Regulates temperature Produces hormones Controls secretion from the pituitary gland
Regulates breathing, reflexes, and the sleep/wake cycle. Part of the brainstem.
Pons
Part of the brainstem that processes and routes visual and auditory stimuli to the thalamus. Carries motor fibers from the cerebral cortex. Monitors movement with the basal nuclei.
Midbrain
Collection of more than 100 nuclei. Part of the brainstem involved in sleep and arousal, pain transmission, playing a role in mood regulation. Involved in any homeostatic functions.
Reticular formation
Three features inside the skull that function in protection?
Cranial meninges (membranes)
Cerebrospinal fluid
Blood-brain barrier
The outermost cranial menix, the thickest and toughest.
Between this and the cranial bones is this potential space.
Deep to the first is another narrow space, which houses a thin layer of serous fluid and certain veins that drain the brain.
Dura mater
Epidural space
Subdural space
Middle cranial menix.
The thinnest and innermost menix.
These are separated by another narrow space that contains the CSF and the major blood vessels of the brain.
Arachnoid mater
Pia mater
Subarachnoid space
Two layers of the dura mater. Outermost is attached to inner surface of the bones of the cranial cavity, functions as the periosteum of those bones and has extensive blood supply.
The inner avascular layer lies superficial to the arachnoid mater.
Periosteal dura
Meningeal dura
The cavities within the right and left cerebral hemispheres. Considered the first and second ventricles.
Right and left lateral ventricles
The narrow cavity housed between the two lobes of the diencephalon. Continuous with the lateral ventricles via the opening intraventricular foramen.
Third ventricle
Cavity situated between the pons and the cerebellum. Continuous inferiorly with the central canal of the spinal cord. Contains several posterior openings that allow CSF in ventricles to flow into subarachnoid space.
Fourth ventricle
Third ventricle drains into it via the cerebral aqueduct, a small canal that passes through the midbrain of the brainstem.
Clear, colorless liquid similar in composition to plasma. Protects the brain through cushioning, maintaining a constant temp, removing wastes, and increasing buoyancy.
Cerebrospinal fluid
Forms most CSF within each off the four ventricles. Located where blood capillaries come into contact with ependymal cells lining the ventricles.
Choroid plexuses
Keeps the CSF and brain ECF separate from the blood. Consists mainly of simple squamous epithelial cells (endothelial cells) of the blood capillaries in the brain and their basal laminae, as well as astrocytes.
Blood-brain barrier
How are the endothelial cells of the blood-brain barrier unique?
They have more tight junctions than cells of most capillaries, largely due to astrocytes.
They limit endocytosis and exocytosis, especially of large polar molecules.
Composed primarily of nervous tissue. Receives outgoing info from the brain and sends to the body, and vice versa. It also does some integration and processing.
Spinal chord
As with the brain, the spinal cord has these three meninges?
Dura mater, which lacks a periosteal layer and consists only of a meningeal layer.
Arachnoid mater
Pia mater, which helps anchor the spinal cord in its cavity.
Thin pieces of the spinal pia that extend outward through the arachnoid and attach to the spinal dura.
Denticulate ligaments
Space that exists between the meningeal dura and the walls of the cerebral foramina. Filled with veins and adipose tissue, which helps cushion and protect the spinal cord.
Epidural space
A potential space in the spinal cord, much like the epidural space around the brain.
Subdural space
Spinal space that lies between the arachnoid and the pia, filled with a very thin layer of CSF. Area inferior to the base of the spinal cord contains a large volume of CSF, making it a good sample spot.
Subarachnoid space
The end of the spinal cord forms this?
At the level of the first and second lumbar vertebrae, the spinal pia gathers into a very thin structure known as this, which continues through the better beak cavity and anchors into the first coccygeal vertebrae?
Conus medullaris
Filum terminals
The nerve roots that fuse to form the spinal nerves serving the upper and lower limbs attach to what?
Cervical enlargement
Lumbar enlargement
Roots of the spinal nerves extending inferiority from the conus medullaris and filling the remainder of the vertebral cavity.
Cauda equina
A thin strip of gray matter connecting the wings in the spinal cord, surrounding the central canal.
Gray commissure
The neurons of this part of the spinal cord are concerned with somatic motor functions, those of the skeletal muscles.
Anterior horn
Part of the spinal cord that contains the cell bodies of neurons that are involved in processing both somatic and visceral incoming sensory info.
Posterior horn
Part of the spinal cord with neurons responsible for motor control of the viscera via the autonomic motor system.
Lateral horn
The relaying part of the spinal cord is carried out by this, which contains the axons of neurons that travel to and from the brain.
White matter
Each region of the spinal white matter is called this. Three lie on each side of the spinal cord?
Funiculus Posterior Lateral Anterior The white matter within each is further organized into columns/tracts.
Carries somatosensory info including fine touch, vibration, and proprioception from the lower limbs.
Ascending tract
Posterior columns-
Fasciculus gracilis
Carry somatosensory info including fine touch, vibration, and proprioception from the trunk, neck, and upper limbs.
Ascending
Posterior columns-
Fasciculus cuneatus
Carry proprioceptive info to the cerebellum
Ascending
Spinocerebellar tracts
Carry info about pain, temperature, and certain types of touch.
Ascending
Anterolateral system-
Spinothalamic tracts
Carry motor info from the motor areas of the cerebral cortex.
Descending
Corticospinal tracts
Carry motor info from the brainstem. Important for the maintenance of posture and proper orientation of the limbs during movement.
Descending
Reticulospinal tracts
Carries motor info from the superior colliculus of the brainstem. Important for reflexive movement of the head and eyes.
Descending
Tectospinal tract
Carries motor info from the vestibular nuclei in the brainstem. Important for maintenance of posture and balance.
Descending.
Vestibulospinal tract
Area in the frontal love responsible for the production of language, including the planning and ordering of words with proper grammar and syntax.
Broca’s area
Area in the temporal love responsible for understanding language and linking a word with its correct symbolic meaning.
Wernicke’s area
Memory of things that are readily available to consciousness that could in principle be expressed out loud.
Declarative (fact) memory
Memory that tends to include skills and associations that are largely unconscious.
Nondeclarative memory
