Central Nervous System Flashcards
What are the general regions of the brain?
cerebrum, diencephalon, cerebellum, brainstem
What are the specific regions of the brain?
Diencephalon: thalamus, epithalamus, hypothalamus
Brainstem: midbrain, pons, medulla oblongata
dura mater
outermost, tough membrane, attaches to bone
arachnoid mater
spider web filamentous layer
pia mater
thin vascular layer adherent to contours of brain
What are ventricles and what is their function?
-spaces in the brain
-contains CSF
What are the functions of cerebrospinal fluid?
Buoyancy, protection, chemical stability
What is hydrocephalus?
CSF cannot circulate and drain properly, leading to brain distortion
In what part(s) of the brain does the cerebrospinal fluid flow inside?
-begins in the choroid plexus
-circulates through ventricles to central canal of spinal cord
-to subarachnoid space of cord and brain
-then up to be absorbed by arachnoid villi
Gyri
elevated folds
Sulci
shallow grooves
Fissures
deep grooves
What are the functions of the left hemisphere?
speech, verbalization, math, logic
What are the functions of the right hemisphere?
visual-spatial skill, intuition, emotion
What is the function of the frontal lobe?
contains voluntary motor for planning, mood, smell, and social judgement
What is the function of the parietal lobe?
integrates sensory in shape, textures, speech
What is the function of the occipital lobe?
optical
What is the function of the temporal lobe?
areas for hearing, emotional behavior, learning, memory, smell
What is the function of the insula?
apparently involved in memory and taste
Commissural fibers
connecting hemispheres
Association fibers
connecting different parts of same hemisphere
Projection fibers
run vertically, ascending fibers carry sensory info and descending fibers carry motor info
What are basal nuclei? What are its functions?
Basal nuclei are masses of gray matter deep to cerebral cortex
Function: involved in motor control, associated with memory, learning, and Ach
What are the functions of gray matter?
Involved in motor control
Sensory areas
conscious awareness of sensation
Association areas
integrate info
Motor areas
control voluntary motor function
Motor (nonfluent) aphasia
-lesion in Broca’s area
-know what they want but can’t say
Fluent aphasia
-lesion in Wernicke’s area
-words easily spoken but used incorrectly
Thalamus
located superior to midbrain
-relay station for sensory impulses (except smell) to cerebral cortex
Hypothalamus
-inferior to thalamus
-relay station for smell
-links nerves to endocrine system via pituitary gland
-regulates homeostasis, controls ANS, secretes hormones
Epithalamus
-contains pineal gland which gets smaller as we age and secretes melatonin that helps regulate circadian rhythms
-in sympathetic division of ANS
Midbrain
btw diencephalon and pons, mediates visual and auditory reflexes
Pons
bridge connecting cerebral cortex and cerebellum, relays nerve impulses related to voluntary skeletal movements
Medulla oblongata
-heart rate, respiratory rate, adjust blood vessel diameter
-reflexes for coughing, sneezing, gagging, swallowing, vomiting, and hiccupping
Brainstem
-bidirectional passageway for tracts btw cerebrum and spinal cord
-contains cranial nerves
-performs automatic behaviors necessary for survival and integrates audio and visual reflexes
what are the functions of the spinal cord?
Involved in sensory and motor innervation of body below head
White matter: two way conduction pathway
Gray matter: major center of reflexes
How are neurons functionally organized in the spinal cord?
Segmented: cervical, thoracic, lumbar, sacral
What is the organization of gray matter in the spinal cord?
divided into posterior horns, anterior horns, lateral horns (only found in thoracic and lumbar regions)
What is the organization of white matter in the spinal cord?
-three columns of ventral, dorsal, and lateral
-further divided into sensory and motor tracts with ascending, descending, and commissural fibers
primary motor cortex
precentral gyrus, In front central sulcus, frontal lobe, generate signals for movement of body
primary somatosensory cortex
postcentral gyrus, Posterior to central sulcus, in parietal lobe, processing somatosensory input and contributes to integration of sensory and motor signals
