Low Yield (for those who want to get a 260 on STEEP) Flashcards
(101 cards)
What are the cortical syndromes associated with PCA occlusion?
- P2: cortical and temporal lobe signs
- Contra homonymous hemianopia with macular sparing
- Acute disturbance in memory if lesion reaches hippocampus

WDescribe the pathway of pupillary constriction reflex.

HSV infection affects?
Temporal and inferior frontal lobes
What is the neural circuit of smooth pursuit eye movement?
Retinal Image -> Ret Ganglion Cells -> LGN -> Visual Cortex -> Reticular Form -> CN III
What is the input, output and function of the vestibulocerebellum?
Input - Vestibular
Output - vestibular
Function - VOR and postural
What are the arrows pointing to and what symptoms could appear if damage were to occur to these areas?


Superior cerebellar peduncle contains?
mostly efferent fibers, sending impulses to thalamus and spinal cord, with relays in the red nuclei; afferent fibers from the ventral spinocerebellar tract enter here
How is temperature info conveyed to the hypothalamus? Which nucleus of the hypothalamus senses temperature
Somatosensory system - temperature sensitive afferents
neurons in anterior nucleus of hypothalamus sense temp
What are the general characteristics of the parietal cortex (Areas 5 & 7)?
- Parietal cortex influences movements related to “extrapersonal space”
- Defined as the space external to the body but within reach for exploration
- Using arm and hand movements
- General function in motor control is selective attention to objects of motivational interest
What is the vestibulo-postural reflex seen in the post-rotational component
In a pt who was previously spinning to the right (decel to right/ accel to left)
- Subject will fall to the right – opposite the direction of acceleration
- Increased left CN VIII firing -> Increased firing of vestibulospinal neurons
- Causes excitation of extensors on left -> Extension
- Decreased right CN VIII firing -> Decreased firing of vestibulospinal neurons
- Causes inhibition of extensors on right -> Flexion
What are symptoms of lesions of the cerebrocerebellum?

What is the pupillary dilation reflex (startle, arousal)?

What are the common syndromes associated with blockage of the posterior cerebral artery?

What is the general pattern for the flow of information in the primary motor cortex
General pattern of information flow: basal ganglia + cerebellum + parietal cortex –> SMA and premotor cortex –> primary motor cortex –> corticospinal output to motoneurons.
What are the VOR effects in post-rotational component?
In a patient who was previously spinning right (decel righ/accel left)
- Slow conjugate eye movements to the right followed by nystagmus to the left
- Increased left CN VIII firing ⇒ Increased Med Vestibular Nuc firing
- Caused decreased left CN VI and decreased right CN III
- Decreased right CN VIII firing à Increased Med vestibular Nuc firing
- Causes increased right CN VI and increased left CN III
Results in nystagmus to opposite direction results as a reflex

Lesions of the superior colliculus tend to have?
Less accurate voluntary saccades
What are the limbic system nuclei of the thalamus? (2)
Medial Dorsal – part of the “drive” pathway between the amygdala, nucleus acumbens and orbitofrontal cortex
Anterior nucleus – part of the Papez memory circuit

What is the input, output, and function of the basolateral pathway of amygdala?
-Functions: reaction to sensory information, comparisons to previous memories and information, decision making and conscious response formation
- Input: neocortical sensory association cortex (temporal lobe)
- Output: orbitofrontal cortex, dorsomedial thalamus, nucleus acumbens, hypothalamus

Area 7 specifically has the function of?
- controls eye movements
- Neurons issue commands to the frontal eye fields for eye movements to achieve and maintain fixation of objects of interest in extrapersonal space
- Neurons include: saccade related, smooth pursuit related and fixation related
Area 5 specifically has the function of?
- controls arm movements
- Neurons issue commands to motor cortex for manual exploration of objects of interest in extrapersonal space
What are the motor system nuclei of the thalamus? (2)
VL – relays basal ganglia and cerebellar info to motor and premotor cortex feed forward system to smooth out movements
VA – relays basal ganglia info widespread areas of frontal cortex - projects to the frontal eye fields and premotor cortex

What is the mechanism by which the ampullae (semicircular canals) detech angular acceleration?
- Hair cells are located in ampullae on a ridge of tissue called the crista ampullaris
- Stereocilia are embedded in the cupula, a tall glycoprotein matrix mass
- Cupula is deflected by fluid flowing through the canal when the head turns
- Results in bending of stereocilia
What are the symptoms seen with a unilateral labyrinthectomy?
Imbalance of input from the semicircular canals due to the high tonic background firing rate present in the unaffected side (elicits both a vestibulo-ocular and vestibulo-postural reflex)
- Fall towards the side of the lesion
- Nystagmus away from the side of the lesion
What occurs in a bilateral vs unilateral ACA occlusion?





























