Lecture Quiz 1 Flashcards
What is the general job of the nervous system?
sensory input
integration
motor output
What does the central nervous system consist of? What is its general function?
brain and spinal cord
acts as integration and command center
What does the peripheral nervous system consist of? What is its general function?
paired spinal and cranial nerves
carries messages to and from the spinal cord and brain
Describe somatic sensory afferent fibers
sensory division
carry impulses from skin, skeletal muscles, and joints to the brain
Describe visceral sensory afferent fibers
sensory division
transmit impulses from visceral organs to the brain
What is the motor division responsible for in the PNS?
transmits impulses from the CNS to effector organs
What does the somatic nervous system do?
conscious control of skeletal muscles
voluntary
What does the autonomic nervous system do?
regulates smooth muscle, cardiac muscle, and glands
divided into sympathetic and parasympathetic
What is a nucleus in the nervous system?
cluster of cell BODIES found in the CNS
What is a ganglion in the nervous system?
cluster of cell BODIES found in the PNS
What is a nerve in the nervous system?
a bundle of AXONS found in the PNS
What is a nerve tract in the nervous system?
a collection of axons in the CNS having the same origin, termination, and function
What is cephalization?
elaboration of the anterior portion of the CNS
increase in number of neurons in the head
highest level is reached in the human brain
What does the surface anatomy of the brain consist of?
includes cerebral hemispheres, cerebellum, and brain stem
What is gray matter?
collection of neuronal cell bodies and their dendrites
What is white matter?
collection of myelinated nerve fibers
What is the ectoderm?
cell layer at the dorsal surface of developing brain
What happens during the first 26 days of embryonic development of the brain?
ectoderm thickens, forming the neural plate
neural plate invaginates, forming the neural groove
neural groove fuses dorsally and forms the neural tube
anterior -> brain ; posterior -> spinal cord
Describe the formation of the primary brain vesicles
anterior end of the neural tube expands and constricts to for the three primary brain vesicles
What are the three primary brain vesicles?
prosencephalon
mesencephalon
rhombencephalon
When do secondary brain vesicles development? What are they (5 - one unchanged)
in week 5 of embryonic development, secondary brain vesicles form telencephalon diencephalon mesencephalon metencephalon myelencephalon
What adult brain structures for from the telencephalon?
cerebrum: cortex
white matter
basal nuclei
What adult brain structures for from the diencephalon?
thalamus
hypothalamus
epithalamus
retina
What adult brain structures form from the mesencephalon?
brain stem - midbrain
What adult structures form from the metencephalon
brain stem: pons, cerebellum
What adult structures form from the myelencephalon?
medulla oblongata
What does the telencephalon develop into in the neural canal?
lateral ventricle
What does the diencephalon develop into in the neural canal?
third ventricle
What does the mesencephalon develop into in the neural canal?
cerebral aqueduct
What does the metencephalon and myelencephalon develop into in the neural canal?
fourth ventricle
Describe the basic pattern of the spinal cord
central cavity is surrounded by a gray matter - inner zone
external to which is white matter composed of myelinated fiber tracts
Describe the basic pattern of the brain
similar to spinal cord but with additional areas of gray matter
cerebellum has gray matter in cortex
cerebrum has nuclei and additional gray matter in the cortex
Where do the ventricles of the brain arise from?
expansion of the lumen of the neural tube
Describe the ventricles of the brain
paired C-shaped lateral ventricles
third ventricle is found in the diencephalon
fourth ventricle is found in the hindbrain dorsal to the pons
Describe the cerebral hemisphere of the brain
forms the superior part of the brain and makes up 83% of its mass
What are the ridges and shallow grooves of the cerebrum called?
ridges = gyri
shallow grooves = sulci
What are the deep grooves of the brain?
fissures
What are the three basic regions of the cerebrum?
cortex
white matter
basal nuclei
What are the five lobes of the brain and what are they separated by?
deep sulci separate them frontal parietal temporal occipital insula central sulcus separates the frontal and parietal lobes
What are the three major lobes, gyri, and sulci of the cerebral hemisphere?
parieto-occipital sulcus - separates parietal and occipital lobes
lateral sulcus - separates the parietal and frontal lobes
precentral and postcentral gyri border the central sulcus
Describe the cerebral cortex
superficial gray matter
accounts for 40% mass of the brain
What does the cerebral cortex enable?
sensation communication memory understanding voluntary movements
Describe the functionality of the cerebral cortex in respect to hemispheres
each hemisphere acts colaterally (controls opposite side of the body)
hemispheres are not equal in function (there is cerebral dominance - left = mathematical and right = creative)
no functional area acts alone - conscious behavior involves the entire cortex
What are the three functional areas of the cerebral cortex and what do they control?
motor areas - control voluntary movement
sensory areas - conscious awareness of sensation
association areas - integrate diverse information
What do the functional areas of the cerebral cortex contain?
gray matter neuron cell bodies dendrites associated glial cells blood vessels
Describe the functionality of the primary motor cortex
located in the precentral gyrus
allows conscious control of precise, skilled, voluntary movement
What is the primary motor cortex made up of?
pyramidal cells whose axons make up the corticospinal tracts
Describe the functionality of the premotor cortex
controls learned, repetitious, or patterned motor skills (i.e. typing)
coordinates simultaneous sequential actions
involved in the planning of movements
Describe the location and functionality of Broca’s area
present in only one hemisphere (usually the left)
a motor speech area that directs muscles of the tongue
active as one prepares to speak
What is Broca’s Aphasia?
discovered in 1861
pt’s cannot put together complex sentences
Describe the local eye field
located anterior to the premotor cortex and superior to Broca’s area
controls voluntary eye movement
Describe the primary somatosensory cortex
Located in the post central gyrus
receives information from the skin and skeletal muscles
exhibits spatial discrimination - determines which part of the body is affected
What is the function of the somatosensory association cortex?
integrates sensory information
forms the comprehensive understanding of the stimulus
determines size, texture, and relationship of parts - determines what something is based on touch
Describe the visual area of the cortex - 2
primary visual cortex - receives visual information from the retinas
visual association area - interprets visual stimuli - color, movement, form
What does the primary auditory cortex do?
receives information related to pitch, rhythm, and loudness
What does the auditory association area do?
stores memories of sounds and permits perception of sounds
aka Wernicke’s area
What is the functionality of the anterior association area?
involved with intellect, cognition, recall, and personality
necessary for judgment, reasoning, persistence, and conscience
closely linked to the limbic system
What is the functionality of the posterior association area?
found in one hemisphere - usually the left
integrates incoming signals into a single thought
involved in processing spatial relationships
What is the functionality of the limbic association area?
involved in emotion and memory
What is lateralization?
each brain hemisphere has abilities not shared with its partner
What is cerebral dominance?
designates the hemisphere dominant for language
What does the left side of the brain control in 90% of people?
language, math, logic
What does the right side of the brain control in 90% of people?
visual-spatial skills, emotion, and artistic skills
What does cerebral white matter consist of?
deep myelinated fibers and their tracts
What is cerebral white matter responsible for?
communication between the cerebral cortex and lower CNS center as well as areas of the cerebrum
What are commisures?
white matter
connect corresponding gray areas of the two hemispheres
What are association fibers?
white matter
connect different parts of the same hemisphere
What are projection fibers?
white matter
enter the hemispheres from lower brain or cord centers, and those leave the cortex to the lower areas
What are the basal nuclei?
masses of gray matter found deep within the cortical white matter
What is the corpus striatum and what is it composed of?
basal nuclei ** recheck this card
composed of three parts:
caudate nucleus
lentiform nucleus (composed of the putamen and the globus pallidus)
fibers of the internal capsul running between and through caudate and lentiform nuclei
What are the functions of the basal nuclei (4)?
influence muscular activity
regulate attention and cognition
regulate intensity of slow or stereotyped movements
inhibit antagonistic and unnecessary movement
What is the largest commisure?
corpus callosum
