Ch. 11 Nervous System Flashcards
chiasm-
Cross
flacc-
flabby
funi-
small cord or fiber
gangli-
Swelling
mening-
membrane
plex-
interweaving
The central nervous system (CNS) consists of
brain and the spinal cord.
The brain is the largest and most complex part of the nervous system. It oversees many aspects of physiology,
sensation and perception, movement, and thinking.
The brain connects to the spinal cord
through the brainstem
Bones, membranes, and fluid surround the organs
of the CNS.
meninges
Beneath these bony coverings, membranes called _____, located between the bone and the soft tissues of the nervous system, protect the brain and spinal cord
The meninges are three connective tissue membranes:
dura mater, arachnoid mater, and pia mater
Dura Matter
outermost layer of the meninges surrounding the brain and spinal cord
Falx cerebelli
Separates the right and left cerebellar hemispheres
Falx cerebri
Extends downward into the longitudinal fissure, and separates the right and left cerebral hemispheres
Tentorium cerebelli
Separates the occipital lobes of the cerebrum from the cerebellum
The arachnoid mater
“spider like ,is a thin, web-like membrane that does not have blood vessels and is located between the dura and pia maters.
A subarachnoid
space between the arachnoid and pia maters contains the clear, watery cerebrospinal fluid
The subarachnoid space of
the meninges completely surrounds the brain and spinal cord, so these organs in effect float in the CSF.
CSF in Meninges
The fluid protects the brain and spinal cord by absorbing forces that might otherwise jar and damage their delicate tissues.
The pia mater
“gentle mother is thin and contains many nerves, as well as blood vessels that nourish the underlying cells of the brain and spinal cord.
ventricles
CSF is formed in four interconnected cavities called that lie in the cerebral hemispheres and brainstem and reference plates 13 and 14
Structures called choroid plexuses
Choroid plexuses in ventricle walls secrete cerebrospinal fluid. Most of the fluid circulates through the ventricles and enters the subarachnoid space, and is reabsorbed into the blood.
CSF in the whole system is what
is a clear, somewhat viscous liquid that differs in composition from the fluid that leaves the capillaries in other parts of the body.
helps maintain a stable ionic concentration in the CNS and provides a pathway to the blood for waste.
The brain
sensory functions responsible for sensations perceptions. issues motor commands to skeletal muscle, mental functions memory reasoning , coordinates movements regulate visceral activities, personality
A lumbar puncture (spinal tap) measures
CSF pressure.
hydrocephalus,
In a fetus or infant whose cranial sutures have not yet united, increasing ICP may enlarge the cranium, or “water on the brain”
BrainStem
Together, the midbrain, pons, and medulla oblongata comprise ____ which attaches the brain to the spinal cord.
Brain forms 3 vesicles cavities
Forebrain Prosencephalon
Midbrain Mesencephalon
Hindbrain Rhombencephalon
Forebrain / prosencephalon divides
into the telencephalon and diencephalon
Midbrain mesencephalon
presist
Hindbrain rhombencephalon
divides into metencephalon and myelencephalon
Major portions of the brain
Cerebrum , Diencephalon, Cerebellum, Brainstem
cerebral hemispheres
in the cerebrum
2 halves separated by falx cerebri
Corpus callosum
in the cerebrum , connects cerebral hemispheres
Gyri
in the cerebrum ridges or convolutions
Sulci
In the cerebrum shallow grooves in surface example central sulcus
Fissures
in cerebrum deep grooves in surface
longitudinal separates the cerebral hemispheres
Transverse separates cerebrum from cerebellum
5 lobes of the cerebral hemispheres
frontal lobe
parietal lobe
temporal lobe
occipital lobe
Insula Island of reil deep within lateral sulcus.
Cerebral Cortex
Thin layer of gray matter which makes up outermost layer of all outer lobes of the cerebrum
Contains almost 75% of neuron cell bodies in nervous system
White matter of cerebrum
Lies under cerebral cortex
makes up most of cerebrum
contains bundles of myelinated axons that connect neuron cell bodies in cerebral cortex to other portions of nervous system.
Functions of the Cerebral Cortex
interpreting impulses from sense organs, initiating voluntary muscular movements, storing information as memory, and retrieving this information in reasoning. intelligence and personality.
cutaneous sensory area
cortex
parietal lobe
interprets sensations on skin
Sensory speech are wernickes area
Cortex
Temporal parietal lobe usually left hemisphere
understanding and formulating language
Visual area
Cortex
occipital lobe
interprets vision
Auditory area
cortex
Temporal lobe
Interprets hearing
Sensory area for taste
Cortex
Near base of the central sulcus
includes part of insula
sensory area for smell
cortex
arises from centers deep within temporal lobes
Association areas
analyze and interpret sensory experiences and help provide memory, reasoning, verbalizing, judgment, and emotions
Frontal lobe association areas
Concentrating, planning, complex problem solving
* Emotional behavior, judging consequences of behavior
Parietal lobe association areas:
- Understanding speech
- Choosing words to express thoughts and feelings
Temporal lobe association areas:
- Interpret complex sensory experiences (understanding speech,
reading) - Store memories of visual scenes, music, and complex patterns
Occipital lobe association areas
Occipital lobe association areas:
* Analyze and combine visual images with other sensory experiences
Insula does
- Translating sensory information into proper emotional responses
Wernicke’s area is usually in the
left hemisphere, in the temporal lobe adjacent to the parietal lobe, near the posterior end of the lateral sulcus (fig. 11.8). This area is important for understanding and formulating written and spoken language.