exam 2 -brain Flashcards
the brain is composed of
cerebrum
cerebellum
brainstem
brainstem consists of
midbrain
pons
medulla oblongata
function of medulla oblongata
Is a relay center for sensory input and motor input
- also responsible for many basic reflex actions
- contains pyramids, autonomic nervous system center, interior part of 4th ventricle
What is the cerebellum
not part of the brainstem
- concerned with higher motor and sensory functions
- left and right cerebellar hemispheres
- contains cerebellar peduncles
pyramids
bilateral ridges on anterior side
- contain only motor neurons
- most axons cross over to the other side (decussate)
autonomic nervous system center is composed of
cardiac center
Vasomotor center
Respiratory center
what is the cardiac center
regulates heart rate and strength of contraction
what is the vasomotor center
constricts and dilates arterioles
- regulates blood pressure
- constrict = raise pressure
- dilate = lower pressure
what is the respiratory center
regulates breathing rate
what is the pons
- middle portion of brainstem
- composed of groups of axons
- attains: Pontine respiratory center and superior part of 4th ventricle
function of pontine respiratory center
helps control Raye and depth of breathing
Describe the location of the superior part of the 4th ventricle
continuous with cerebral aqueduct
Midbrain
Superior part of the brainstem that connects the brainstem to the diencephalon
- contains tectal plate, cerebral peduncles, and cerebral aqueducts
What is the tectal plate
posterior aspect of midbrain
Subdivided it into: Superior and inferior colliculi
Function of superior colliculi
visual reflex centers
- coordinates head and eye movements to sudden image
function of inferior colliculi
auditory reflex centers
- coordinates head and eye movements to sudden sound
what are cerebral peduncles
groups of axons on anterior side of midbrain
- motor axons only
- conduct nerve impulses between cerebrum and brainstem
what is the cerebral aqueduct
connects 4th ventricle to 3rd ventricle
what are the cerebellar peduncles
group of axons
- inferior cerebellar peduncles
- middle cerebellar peduncles
- superior cerebellar peduncles
location purpose of inferior cerebellar peduncles
connect medulla oblongata to cerebellum
location purpose of middle cerebellar peduncles
connect pons to cerebellum
location purpose of superior cerebellar peduncles
connect midbrain to cerebellum
what is the function of cerebellar peduncles
- “fine tunes” skeletal muscle movement
- maintains balance
- assists cerebrum in regulation of behavioral expression, cognitive skills, language retrieval
what part of the brain initiates movement?
cerebrum
how do alcohol and drugs play a role in the cerebrum
- uncoordinated (ataxia)
- loss of balance and posture
- inability to detect info (finger to nose with eyes closed)
order of cranial meninges from deepest to most superior
pia mater -subarachniod space arachniod mater dura mater -inner meningeal layer -outer periosteal layer
what are the dural venous sinuses
- large veins that drain blood from the brain
- between inner meningeal and outer periosteal layers of dura
- vein walls are formed from the dura mater
purpose of CSF
- provides buoyancy for brain and spinal cord
- maintains chemical environment
when and where is CSF made?
produced continuously in the ventricles of the brain–chord plexus
ventricular system consists of
- left and right lateral ventricles
- 3rd ventricle
- cerebral aqueduct
- 4th ventricle