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2- occulomotor
na
58
Other
Graduate
03/09/2010

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Term
we see objects only when they are focused on the _________
Definition
we see objects only when they are focused on the FOVEA
Term
The oculomotor system is designed to:
1: _____ ______ ____ ___ _____
2: _____ ______ ____
Definition
The oculomotor system is designed to:
1: BRING TARGETS ONTO THE FOVEA
2: KEEP THEM THERE
Term
5 movements systems have been identified that put the fovea on a target and keep it there.
Definition
1: Vestibulo-ocular
2: Optokinetic
3: Saccade
4: Smooth Pursuit
5: Vergence
Term
Movements that stabilize the eye when the head moves
Definition
1: vestibulo-ocular
2: optokinetic
Term
movements that keep the fovea on a visual target
Definition
1: saccade
2: smooth pursuit
3: vergence
Term
systems that allow for conjugate movements of the eyes for foveation
Definition
1: vestibulo-ocular
2: optokinetic
3: saccade
4: smooth pursuit
Term
the oculomotor system that allows for disconjugate movements
Definition
4: smooth pursuit.
Term
vestibulo-ocular
Definition
gaze stabilization

vestibular input holds images stable on retina during head and body movement
Term
optokinetic
Definition
visual input holds images stable on retina during sustained or slow head rotation
Term
Saccade
Definition
brings new objects of interest onto fovea
Term
Smooth pursuit
Definition
holds image of a moving target on the fovea
Term
Vergence
Definition
adjusts the eyes for viewing different distances in depth
Term
The ________ system is used to quickly reposition the eyes to focus on an image that has suddenly been moved from the fovea
Definition
The SACCADE system is used to quickly reposition the eyes to focus on an image that has suddenly been moved from the fovea
Term
the rapid eye movement required to bring the image back into focus is a ________
Definition
the rapid eye movement required to bring the image back into focus is a SACCADE
Term
The conjugate system of the saccade systems directed through a _______ ____ _____ located in the pontine reticular formation (_ _ _ _)
Definition
The conjugate system of the saccade systems directed through a HORIZONTAL GAZE CENTER located in the pontine reticular formation (PPRF)
Term
your eyes remain fixed and focused on that position by moving at the _____ _____ as your head, but in the _________ direction
Definition
your eyes remain fixed and focused on that position by moving at the SAME SPEED as your head, but in the OPPOSITE direction
Term
Rotatory nystagmus has __ components, the slow movement of ________, the rapid movement of _________
Definition
Rotatory nystagmus has 2 components, the slow movement of FIXATION, the rapid movement of RESETTING
Term
The continuation of following and resetting of the focal point is now driven by the ______________ ______
Definition
The continuation of following and resetting of the focal point is now driven by the OPTOKINETIC SYSTEM
Term
The optokinetc system requires input from:
the __________ _________
the __________ _________
Definition
The optokinetc system requires input from:
the VISUAL CORTEX
the SUPERIOR COLLICULUS
Term
Once the rotation is stopped, the eyes will react in the __________ direction
Definition
Once the rotation is stopped, the eyes will react in the OPPOSITE direction
Term
Postrotatory nystagmus is _________ driven. The slow following eye movement will be in the ________ direction, and the saccade in the _________ direction of the prior rotation
Definition
Postrotatory nystagmus is VESTIBULAR driven. The slow following eye movement will be in the SAME direction, and the saccade in the OPPOSITE direction of the prior rotation
Term
Smooth persuit requires an image to be moving across the ______ of ______ and is not under ________ control once fixation on the image has been established
Definition
Smooth persuit requires an image to be moving across the FIELD of VISION and is not under VOLITIONAL control once fixation on the image has been established
Term
In smooth pursuit the UMN control comes from visual signals from _______ _______ _______, channeled through an area in the _____ ______ ______ coupled with _______ _________
Definition
In smooth pursuit the UMN control comes from visual signals from PRIMARY VISUAL CORTEX, channeled through an area in the CAUDAL TEMPORAL GYRUS coupled with SUPERIOR COLLICULUS
Term
The involuntary control of saccade and smooth pursuit eye movements are ______ or volunatily as ________ from ______ _____ _______
Definition
The involuntary control of saccade and smooth pursuit eye movements are VOR or volunatily as SACCADES from FRONTAL EYE FIELDS
Term
All of the systems for conjugate eye movements are influenced by _________ through feedback information to the __________ _______ and then to the _______ and/or ______ _______ _______
Definition
All of the systems for conjugate eye movements are influenced by CERBELLUM through feedback information to the VESTIBULAR NEUCLEI and then to the _HORIZONTAL and/or VERTICAL GAZE CENTERS
Term
The Vergence system is controlled through the _______ __________ at the ________ level
Definition
The Vergence system is controlled through the RETICULAR FORMATION at the MIDBRAIN level
Term
Disconjugate movements of the eyes are necessary for the ________ of an image as it moves ______ or ______ from you
Definition
Disconjugate movements of the eyes are necessary for the FOVEATION of an image as it moves TOWARDS or AWAY from you
Term
For convergence, an activation of both _______ ______ _______ must override the _____ _______ _______ tone to bring the eyes together
Definition
For convergence, an activation of both MEDIAL RECTUS MUSCLES must override the LATERAL RECTUS MSUCLE tone to bring the eyes together
Term
To overcome blurring of the image as it comes closer, this mechanism is coupled with _______ _________ and ________ for changing of focal distances
Definition
To overcome blurring of the image as it comes closer, this mechanism is coupled with PUPILLARY CONSTRICTION and ACCOMMODATION for changing of focal distances
Term
_______ ______ nucleus that is located rostrally in the midbrain tectum and recieves UMN fibers from the _________ cortex
Definition
SUPERIOR COLLICULUS nucleus that is located rostrally in the midbrain tectum and recieves UMN fibers from the IPSILATERAL cortex
Term
Tectobulbar conenctions of the neuclei fo the cranial nerves innervating the extraocular eye muscles are a part of: ___________ and __________________ and are analogous to _________
Definition
Tectobulbar conenctions of the neuclei fo the cranial nerves innervating the extraocular eye muscles are a part of: THE PATHWAY FOR VOLUNTARY and INVOLUNTARY EYE MOVEMENTS and are analogous to UMNs
Term
The Superior Colliculus receives retinal projections from the ____ ______via the ________
Definition
The Superior Colliculus receives retinal projections from the OPTIC TRACT via the BCS
Term
Descending efferent information from the superior colliculus is directed to the ______ _______ and _______ _______ ______
Definition
Descending efferent information from the superior colliculus is directed to the SPINAL CORD and CRANIAL NERVE NUCLEI
Term
The Tectospinal tract cross in the midbrain and descends to ______ spinal cord levels. This tract is important in the reflex turning of the _____ and _______ in response to both _______ and ______cues
Definition
The Tectospinal tract cross in the midbrain and descends to CERVICAL spinal cord levels. This tract is important in the reflex turning of the HEAD and NECK in response to both VISUAL and AUDITORY cues
Term
The Pretectal area is located:
Definition
The Pretectal area is Located: ROSTRAL TO THE SUPERIOR COLLICULUS
Term
The Pretectal area receives projections from the _____ ____ _________ and efferents to _________________ and ______________ that are associated with CN _____ for reflex control of the pupil and lens
Definition
The Pretectal area receives projections from the CORTEX RETINA SUPERIOR COLLICULUS and efferents to CRANIAL NERVE NEUCLEI and PREGANGLIONIC PARASYMPATHETIC NEURONS that are associated with CN III for reflex control of the pupil and lens
Term
All of the cranial nerves involved with movement of the eye, voluntary or involuntary, are interconnected through axons traveling in the _______
Definition
All of the cranial nerves involved with movement of the eye, voluntary or involuntary, are interconnected through axons traveling in the MLF
Term
Abducens nerve (CN__) are ____ innervating _____ _____ muscle.
Definition
Abducens nerve (CNVI) are LMNs innervating LATERAL RECTUS muscle.
Term
The abducens nerve (CN __) exits the _______ laterally adjacent to the pyramids at the ______________ junction. Functions in ________ of the eyeball. ______ or the ______ gaze center projects to the abducens nucleus
Definition
The abducens nerve (CN VI) exits the BRAINSTEM laterally adjacent to the pyramids at the PONTOMEDULLARY junction. Functions in ABDUCTION of the eyeball. PPRF or the HORIZONTAL gaze center projects to the abducens nucleus
Term
Horizontal Conjgate gaze are internuclear neurons from the _____ _____ project to the _________ oculomotor complex for _______ of ipsilateral LMNs innervating ______ rectus. Internuclear neurons from the PPRF project to the _________ oculmotor complex for activation of _________ medial rectus. These axons run in the _________ ____
Definition
Horizontal Conjgate gaze are internuclear neurons from the ABDUCENS NUCLEUS project to the IPSILATERAL oculomotor complex for INHIBITION of ipsilateral LMNs innervating MEDIAL rectus. Internuclear neurons from the PPRF project to the CONTRALATERAL oculmotor complex for activation of CONTRALATERAL medial rectus. These axons run in the CONTRALATERAL MLF
Term
___________ is a visible turn of one eye that may be constant and is also termed ______
Definition
STRABISMUS is a visible turn of one eye that may be constant and is also termed TROPIA
Term
______ refers to the point of vergence of the eyes
Definition
PHORIA refers to the point of vergence of the eyes
Term
________ is where the eyes are postured in front of the point of focus and ________ is where the eyes are postured in back of the focus
Definition
ESPHORIA is where the eyes are postured in front of the point of focus and EXPHORIA is where the eyes are postured in back of the focus
Term
_________ is a lesion of the abducens nerve fibers resulting in unopposed adduction of the ipsilateral eye
Definition
ESOTROPIA is a lesion of the abducens nerve fibers resulting in unopposed adduction of the ipsilateral eye
Term
________ ________ (CN__) is LMNs innervating the contralateral superior oblique muscle
Definition
TROCHLEAR NERVE (CN IV) is LMNs innervating the contralateral superior oblique muscle
Term
The trochlear nerve axons course dorsally around the __________ _____ and _______, then courses around the ______ to occupy a position lateral to the ________ nerve b/t the _______ ______ and ______ ______ ______
Definition
The trochlear nerve axons course dorsally around the PREAQUEDUCTAL GREY and DESSUCATE, then courses around the BRAINSTEM to occupy a position lateral to the OCULMOTOR nerve b/t the SUPERIOR COLLICULUS and POSTERIOR CEREBELLAR ARTERIES
Term
___________ ______ (CN __) fucntions in rotation and depression of the eyeball
Definition
TROCHLEAR (CN IV) fucntions in rotation and depression of the eyeball
Term
__________ ____ (CN ___) are LMNs for the extraocular eye muscles and levator palprebae superioris are __________
Definition
OCCULOMOTOR NERVE (CN III) are LMNs for the extraocular eye muscles and levator palprebae superioris are IPSILATERAL
Term
The preganglionic parasympathetic cell bodies of the ________ ____ (CN ___) lie in an adjacent nucleus, the Edinger-Westphal nucleus
Definition
The preganglionic parasympathetic cell bodies of the OCCULMOTOR NERVE (CN III) lie in an adjacent nucleus, the Edinger-Westphal nucleus
Term
The occulomotor nerve (CN __) can be seen exiting between the ______________and _____________ medial to the _______ ______ (CN __).
Definition
The occulomotor nerve (CN III) can be seen exiting between the SUPERIOR CEREBELLAR and POSTERIOR CEREBELLAR ARTERIES medial to the TROCHLEAR NERVE (CN IV).
Term
Fibers from the _______ - ________ nucleus traverse the ___________ near the red nucleus and cross the ________ ______ to exit in the ________ _____
Definition
Fibers from the EDINGER-WESTPHAL nucleus traverse the TEGMENTUM near the red nucleus and cross the CEREBELLAR PEDUNCLES to exit in the INTERPENDUNCULAR FOSSA
Term
_________ is a lesion of the oculomotor nerve (CN III), aka ____________ _______, paralysis of all extraocular muscles except ____ and ___ and results in _________ ______
Definition
EXOTROPIA is a lesion of the oculomotor nerve (CN III), aka OCULMOTOR PALSY, paralysis of all extraocular muscles except LR and SO and results in UNOPPOSED ABDUCTION
Term
Loss of the parasympathetic innervation of the ciliary gangila results in ________ of the ______
Definition
Loss of the parasympathetic innervation of the ciliary gangila results in DILATION of the PUPIL
Term
Horner's syndrom is a lesion of sympathetic nervous system pathway, descending influenc from the __________ directed to __________ sympathetic neurons in the spinal cord, or any of the ______ pathways carrying sympathetic fibers
Definition
Horner's syndrom is a lesion of sympathetic nervous system pathway, descending influence from the HYPOTHALAMUS directed to PREGANGLIONIC sympathetic neurons in the spinal cord, or any of the PERIPHERAL pathways carrying sympathetic fibers
Term
ptosis is:
due to:
Definition
ptosis is:DROOPING OF THE EYELID
due to: LOSS OF SYMPATHETIC INNERVATION TO SUPERIOR TARSAL MSUCLE OF THE EYLID AND ITS CONTROL BY LEVAOR PALPEBRAE SUPERIORIS
Term
Miosis is:
due to:
Definition
Miosis is: PUPIL CLOSED
due to: LOSS OF DILATOR CONTROL, PARASYMPATHETIC UNOPPOSED CONSTRICTOR TONE
Term
Dry skin is:
due to:
Definition
Dry skin is: ABSENCE OF SWEATING
due to: LOSS OF SYMPATHETIC CONTROL OF SWEAT GLANDS
Term
Flushed skin is:
due to:
Definition
Flushed skin is: REDNESS
due to: LACK OF CONSTRICTION OF CAPILLARY FIELD
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