Pyramidal cells
-neurons that control skilled voluntary movements
-axons form tracts of spinal cord
Somatotopy
-mapping of the body in the CNS
Premotor Cortex
-controls learned, patterned, repetitious motor skills
Broca's Area
-present only on left cerebral hemisphere
-speech production
-prepare to speak
-think about speech
-plan motor activities
Frontal Eye Fields
-voluntary eye movement
Primary Somatosensory Area
-receives information from sensory receptors in skin and proprioceptors in skeletal muscle, joints, and tendons
what is spatial discrimination?
-neurons identify region stimulated
Somatosensory Association Cortex
-integrates sensory information like temperature and pressure relayed by primary somatosensory cortex
-allows us to understand the object in question
(keys in pocket)
Primary Visual Cortex
-Receives stimuli from retina
Visual Association Area
-Uses memory and prior visual experience to interpret visual stimuli
Primary Auditory Cortex
-Receives stimuli from hearing receptors in inner ear (loudness, location, pitch)
Auditory Association Area
-Perception of sound based on past experience and memory
(music, thunder)
Olfactory Cortex
-smell
Gustatory Cortex
-taste
Visceral Sensory Area
-gives us sensory information of visceral organs
(upset stomach, full bladder)
Vestibular Cortex
-equilibrium, sense of balance
Wernicke's Area
-speech comprehension
damage to the primary visual cortex would cause what?
what would damage to the visual association area cause?
-blindness
-person can see but does not understand what they are looking at
what do the multimodal association areas do?
assimilate information from the sensory association area and link it to past experience
-sensory receptors
-primary sensory cortex
-sensory association area
-multimodal association areas
what are the 3 multimodal association areas?
-anterior association area
-posterior association area
-limbic association area
what is the anterior association area?
what are its functions??
what is the rate of development in children?
what does it require from the social environment?
-prefrontal cortex
-intellect
-cognition
-personality
-recall
-working memory
-develops slowly in children
-requires positive and negative feedback from social environment
what is the posterior association area?
which lobes compose it?
what are its functions?
-includes parts of temporal, parietal, and occipital lobes
-recognizing patterns and faces
-localization in space
-integrating individual sensory inputs into a coherent concept
-involved in written and spoken language
what composes the limbic association area?
what structures in the brain compose it?
what is its major function?
-cingulate gyrus
-parahippocampal gyrus
-hippocampus
-allows us to experience emotions
what is a gyrus?
elevated ridge of tissue
what is a sulcus?
shallow grooves
what is the term used to describe the elaborate development of the anterior aspect of the CNS through evolution?
cephalization
what is the flat embryonic structure present at 19 days of gestation that eventually develops into the CNS?
neural plate
what is a the hollow, tube-like embryonic structure formed at 26 days of gestation that will eventually develop into the CNS?
what nutrient is required for its proper development?
what birth defect arises from the incomplete development of this structure?
neural tube
folic acid
anencephaly, cerebrum and part of brain does not develop
what structures are found in white matter?
mostly myelinated axons bundled into large tracts
what structures are found in gray matter?
short, non myelinated neurons and neuron cell bodies
what type of matter surrounds the ventricles of the brain and central canal of the spinal cord?
grey matter
what type of matter forms the outer layer of the brain stem and spinal cord?
white matter
what type of matter forms the outer layer of the cerebral hemispheres and cerebellum? what is it called?
outer layer of grey matter
the cortex
what are spaces in the brain? where do originate from?
ventricles
central cavity of the neural tube
what are ventricles filled with? what cells line these spaces?
cerebrospinal fluid
ependymal cells
what are the 5 lobes of the cerebral hemispheres?
frontal lobe
parietal lobe
occipital lobe
temporal lobe
insula
what are deep grooves on the surface of the cerebral hemispheres?
fissures
what is the groove that separates the right and left cerebral hemispheres?
median longitudinal fissure
what is the groove that separates the cerebral hemispheres from the cerebellum?
transverse cerebral fissure
what is the groove that separates the frontal lobe from the parietal lobe?
central sulcus
what is the groove that separates the temporal lobe from the parietal and frontal lobes
lateral sulcus
gyrus immediately anterior to the central sulcus
precentral gyrus
gyrus immediately posterior to the central sulcus
postcentral gyrus
name seven functions of the cerebral cortex
conscious mind
awareness of ourselves
awareness of our sensations
ability to communicate
ability to remember
ability to understand
initiate voluntary movement
what is the functional area located in the precentral gyrus? what is its function?
premotor cortex
control learned and repetitious motor patterns
what specialized neurons control skilled voluntary movements?
pyramidal cells
what is the mapping of the human body in the CNS called?
somatotopy
what is the cartoon-like image used in somatotopy?
what does it mean if a section of this image is larger?
sensory homunculus
areas of the body with more sensory and motor connections
define "association area" in the cerebral cortex
association areas give us meaning to the information that we receive, store it in memory, and tie it to past experience
what is "lateralization of cortical functioning"?
division of labor between hemispheres where each hemisphere has abilities not completely shared by its partner
what is cerebral dominance
designates the hemisphere dominant for language
most people have dominance of what hemisphere?
left hemisphere
what are the white matter regions in the brain responsible for? name the three fibers that compose this region.
communication between cerebral areas and between the cerebral cortex and lower CNS centers
commissural fibers
association fibers
projection fibers
what are commissural fibers responsible for?
connect corresponding gray areas of the two hemispheres
what are association fibers responsible for?
connect different parts of the same hemisphere
what are projection fibers responsible for?
sensory output reaches the cerebral cortex and motor output leaves through these fibers
they tie the cortex to the rest of the nervous system and to the body's receptors and effectors
name 3 functions of the basal nuclei?
-receives input from the entire cerebral cortex and other nuclei
-relays through the thalamus and projects to premotor and prefrontal cortices
-impacts motor movements directed by the primary motor cortex
what disease results from homeostatic imbalance of the basal nuclei?
Parkinsons disease
what three structures compose the diencephalon?
-thalamus
-hypothalamus
-epithalamus
name 3 functions of the thalamus!
-gateway to the cerebral cortex
-sorts and edits information
-mediates information including sensation, motor activity, cortical arousal, learning and memory
what is the overall function of the hypothalamus?
name seven specific ways in which the hypothalamus accomplishes this...
maintaining homeostasis
-control of endocrine system functioning
-center for emotion response
-regulation of food intake
-regulation of water balance and thirst
-regulation of sleep-wake cycle
-autonomic control center
-body temperature regulation
where is the epithalamus located relative to the thalamus?
inferior
what gland is located in the epithalamus?
what does it secrete?
pineal gland
melatonin, sleep-inducing signal and antioxidant
name the three regions of the brain stem
midbrain
pons
medulla oblongata
state three ways in which the medulla oblongata helps to maintain homeostasis
-cardiovascular centers affect heart contraction and blood pressure
-respiratory centers controls breathing
-other centers control vomiting, swallowing, coughing, and sneezing
where is the cerebellum located?
what is the role of the cerebellum in coordination?
occipital lobe, inferior to the pons and medulla
processes inputs received by the cerebral motor cortex, various brain stem nuclei, and sensory receptors to provide precise timing of skeletal muscle contraction for smooth, coordinated movements
what are three cognitive functions of the cerebellum?
recognize and predict sequence of events
word association
puzzle solving
what is a psychosomatic illness?
how does the hypothalamus contribute to psychosomatic illness?
disorders with physical symptoms that originate from emotional causes
most of the limbic system goes through the hypothalamus
name two functions of the reticular formation
keeps brain alert and conscious
filters sensory impulses only strong impulses go to consciousness
state 4 structures that protect the brain
skull
meninges
cerebrospinal fluid
blood-brain barrier
name the three layers of meninges from deep to most superficial
-pia mater
-arachnoid mater
-dura mater
what are the two layers of the dura mater?
meningeal layer
periosteal layer
which layer of the dura mater is present around the spinal cord?
meningeal layer
describe the anatomic location of the following extensions of the dura mater:
falx cerebri?
falx cerebelli?
tentorium cerebelli?
falx cerebri, divides cerebral hemispheres
falx cerebelli, vermis of cerebellum
tentorium cerebelli, in transverse fissure between cerebral hemispheres and cerebellum
what is the function of cerebrospinal fluid?
where is it produced?
protects the brain and spinal cord
choroid plexus, the roof of each ventricle
describe the route of flow of CSF
-choroid plexus
-third ventricle --> fourth ventricle
-subarachnoid space and central canal of spinal cord
-circulates due to motion of cilia on ependymal cells
-returns to blood of dura sinus through the arachnoid villi
what is the blood-brain barrier?
where is it absent
-selectively permeable barrier created by capillary endothelial cells joined by tight junctions, maintains a stable environment for the brain
-hypothalamus
what is the name for the inferior end of the spinal cord?
conus medullaris
what is the name for the collection of nerve roots at the inferior end of the spinal cord?
cauda equina
what is the name of the fibrous extension that anchors the spinal cord to the coccyx?
filum terminale
at what spinal level is the inferior end of the spinal cord located?
L1-L2
At what level is a spinal tap performed and why?
Below L3 because the spinal cord is absent and the nerve roots of the cauda equine drift away from the needle
what does the ventral horn carry?
motor fibers
what does the dorsal horn carry?
sensory fibers
dorsal roots fuse to form what?
spinal nerve
in the white matter of the spinal cord,
ascending fiber tracts carry ______
descending fiber tracts carry ______
sensory information
motor information
what is the location and function of the fasciculus cuneatus spinal cord tract?
-dorsal funiculus
-general sensation and proprioception from upper limbs, upper trunk, and neck
what is the location and function of the fasciculus gracilis spinal cord tract?
-dorsal funiculus
-general sensation and proprioception from lower limbs and inferior body trunk
what is the location and function of the lateral spinothalamic spinal cord tract?
-lateral funiculus
-pain and temperature impulses
what is the location and function of the ventral spinothalamic spinal cord tract?
-ventral funiculus
-crude touch and pressure impulses
what is the location and function of the dorsal spinocerebellar spinal cord tract?
-lateral funiculus
-subconscious proprioception from trunk and lower limb to cerebellum on same side of body
what is the location and function of the lateral corticospinal spinal cord tract?
-lateral funiculus
-motor impulses from cerebrum to spinal cord motor neurons (voluntary motor tracts)
what is the location and function of the ventral corticospinal spinal cord tract?
-ventral funiculus
-motor impulses from cerebrum to spinal cord motor neurons (voluntary motor tract)
what is the location and function of the tectospinal spinal cord tract?
-ventral funiculus
-turns eyes so neck can follow a moving object
what is the location and function of the vestibulospinal spinal cord tract?
-ventral funiculus
-motor impulses that maintain muscle tone
what is the location and function of the rubrospinal spinal cord tract?
-lateral funiculus
-control flexor muscles in animals, lesser function in humans
what is the location and function of the reticulospinal spinal cord tract?
-medial and lateral funiculus
-impulses for muscle tone and visceral motor functions