neuro opto summer 3rd quiz add

What system adjusts fixation when a visual target moves, during head movements, and when acquiring a new target?

Eye Movements

What is the highest level of ocular motor control that directs eye movements but does not directly innervate extraocular muscles?

Supranuclear Control

What level of the ocular motor system contains the cranial nerve nuclei responsible for eye movements?

Nuclear System

What level of the ocular motor system includes the cranial nerves and extraocular muscles?

Infranuclear System

What level coordinates communication between ocular motor nuclei?

Internuclear System

What are eye movements called when both eyes move in the same direction?

Versions

What are eye movements called when both eyes move in opposite directions for near or far

Vergence

What type of eye movement is quick, ballistic, and shifts fixation from one target to another?

Saccade

Approximately how much time is required between target onset and the onset of a saccadic eye movement?

200 milliseconds (200 ms)

What type of eye movement is slow, visually guided, and used to track a moving object?

Smooth Pursuit

What eye movement consists of a combination of smooth pursuit and saccadic movements?

Optokinetic Movement (Optokinetic Nystagmus)

What type of eye movement is slow and guided by vestibular input?

Vestibulo-Ocular Movement

What term describes eye movements in which both eyes move in the same direction?

Conjugate Eye Movements

What term describes eye movements in which both eyes move in opposite directions?

Disconjugate Eye Movements

What vergence movement occurs during fixation of near objects, with both eyes adducting?

Convergence

What vergence movement occurs during fixation of distant objects, with both eyes abducting?

Divergence

What does PPRF stand for?

Paramedian Pontine Reticular Formation

What is the horizontal gaze center of the brainstem?

PPRF (Paramedian Pontine Reticular Formation)

Which nucleus receives excitatory input from the right PPRF during right gaze?

Right Abducens Nucleus

Which extraocular muscle is activated by the right abducens nucleus during right gaze?

Right Lateral Rectus Muscle

Which nucleus is activated through internuclear connections to adduct the left eye during right gaze?

Left Oculomotor Nucleus

Which muscle is activated in the left eye during right gaze?

Left Medial Rectus Muscle

What type of neuron that crosses the midline and transmits signals from the abducens nucleus to the contralateral oculomotor nucleus?

Internuclear Neuron

In what brain region is the vertical gaze center located?

Mesencephalon

Which two structures provide upper motor neuronal control of eye movements?

Frontal Eye Field and Superior Colliculus

What Brodmann area corresponds to the frontal eye field?

Brodmann Area 8

Which two structures contain sensory maps representing the contralateral visual hemifield?

Frontal Eye Field and Superior Colliculus

Which two structures contain motor maps for saccadic eye movements?

Frontal Eye Field and Superior Colliculus

To which visual field do the sensory maps of the frontal eye field and superior colliculus correspond?

Contralateral Visual Hemifield

With what two structures is the frontal eye field connected?

Ipsilateral Superior Colliculus and Contralateral Gaze Centers

What type of eye movement is impaired by lesions of the frontal eye field or superior colliculus?

Saccadic Eye Movements

The frontal eye fields are responsible for intentional saccades toward which side?

Contralateral Side

A patient with a lesion of the left frontal eye field cannot intentionally look toward which side?

Right Side

A stroke involving which cortical region may impair intentional gaze toward the opposite side?

Anterior Premotor Cortex

Which structure generates express saccades that are not associated with planned eye movements?

Superior Colliculus

What are the rapid reflexive eye movements generated by the superior colliculus called?

Express Saccades

Which structure causes a person to automatically look toward a sudden sound?

Superior Colliculus