7a and 8a Cerebral Cortex Flashcards
Motor Cortex– purpose and which lobe?
Frontal lobe, control of skeletal muscles
Somatosensory Cortex– purpose and which lobe?
Parietal lobe, sense of touch
Sensory association cortex– purpose and which lobe?
Parietal lobe, integration of sensory information
Visual association cortex– purpose and which lobe?
Occipital lobe, combining images and object recognition
Visual Cortex– purpose and which lobe?
Occipital lobe, processing visual stimuli and pattern recognition
Wernicke’s Area– purpose and which lobe?
Temporal lobe, comprehending language
Primary auditory cortex– purpose and which lobe?
Temporal lobe, hearing
Broca’s area– purpose and which lobe?
Frontal lobe, forming speech
Prefrontal Cortex– purpose and which lobe?
Frontal lobe, decision making, planning
What sulcus separates the frontal and parietal lobes?
Central sulcus (bounds frontal posteriorly and parietal anteriorly)
What sulcus separates the frontal and temporal lobes?
Lateral (sylvian) sulcus (bounds frontal inferiorly and temporal superiorly)
What sulcus separates the parietal and temporal lobes?
Lateral (sylvian) sulcus (bounds parietal inferiorly and temporal superiorly)
What sulcus separates the parietal and occipital lobes?
Parieto-occipital sulcus (posterior to parietal and anterior to occipital)
What is the parieto-occipital sulcus?
A “made up” sulcus separating the occipital lobe from the parietal and temporal sulcus, beginning at the preoccipital notch and traveling up
What lobe is the calcarine sulcus located in?
Occipital lobe
Brodmann’s Areas 44, 45?
Broca’s Area
Brodmann’s Area 22?
Primary auditory cortex
Brodmann’s Areas 1, 2, 3?
Primary somatosensory cortex
Brodmann’s Area 4?
Primary motor cortex
Brodmann’s Areas 39, 40?
Wernicke’s Area
Brodmann’s Area 17?
Primary visual cortex
What will a lesion of the primary motor cortex result in?
Varied degrees of focal paralysis in the contralateral side of the body or face
What is the premotor cortex’s (PMC) role in the brain?
- involved in initiating movements
- concerned with coordinating motor plans related to external ques
- activity greater in response to external cues than internally generated plans
What are the inputs and outputs of the premotor cortex?
Inputs: parietal lobe, cerebellum, prefrontal cortex
Outputs: primary motor cortex
What would a lesion in the premotor cortex result in?
Impairments in motor learning and execution
What does the Supplementary motor area control?
- SMA and the more lateral PMC neurons control the activity of the primary motor cortex neurons
What are the inputs and the outputs of the supplementary motor area control?
Inputs: prefrontal cortex and basal ganglia
Outputs: primary motor cortex
What would a lesion in the SMA result in?
Akinetic mutism, or the inability to follow command of voluntary movement, including speech
What areas of the brain are considered the prefrontal cortex?
Areas of the frontal lobe located anterior to the motor functional areas
From where do the PMC and the SMA both receive inputs from?
Prefrontal cortex
When is the prefrontal cortex most active?
When planning behaviors and when new motor skills are being acquired
Where is the frontal eye field located?
Frontal lobe
What is the function of the frontal eye field?
voluntary lateral, or horizontal, gaze
What happens if the frontal eye field is lesioned?
- eyes will turn to the side of the lesion
- patient cannot gaze voluntarily to contralateral side
Doll’s Eye maneuver, can rule out which CN damage?
CN III, IV, VI, and VIII (damage to the brainstem)
What are the five basic senses?
Salt, sour, bitter, sweet, umami
What is the path of taste signal?
- CN 7, 9, 10 → Medulla (via Nuclear Solitary tract) → some to thalamus, some to limbic regions (amygdala) → orbitofrontal cortex
What is the orbitofrontal cortex thought to be involved in?
Processing the reward value of food and the resulting motivation to eat food
When does transduction from odor to neural signal begin?
When the odorant attaches to a receptor in the olfactory epithelium
What is the path of transduction of an odor?
- olfactory epithelium → olfactory bulbs (via tiny olfactory nerves) → primary olfactory cortex → orbitofrontal cortex
What’s another name for the orbitofrontal cortex?
secondary olfactory cortex
What is the primary olfactory cortex’s purpose?
detects a change in external odor
What is the purpose of the secondary olfactory cortex?
Identifying the smell itself
What is the path of the visual pathway?
Optic nerve → optic chiasm → optic tract → lateral geniculate → optic radiations → primary visual cortex
What percent of optic nerves cross at the optic chiasm?
- 50% cross from the medial half of the retina
- 50% do not cross from the lateral half of the retina
Incoming fibers from the lower retina:
a. stay inferior
b. are superior
a. stay inferior
Which fibers from the retina form Meyer’s loop?
lower retina
Where is Meyer’s loop?
Temporal lobe
Incoming fibers from the upper retina stay:
a. inferior
b. superior
b. superior
Fibers from the upper retina travel in what lobe?
Parietal lobe
True or False? Lesions in the lower part of the retina system (Meyer’s loop, temporal white matter) lead to upper visual field defects
True
True or False? Lesions in the upper part of the retina system (parietal white matter) lead to upper visual field defects?
False
In the primary visual cortex, if a lesion is in the upper calcarine, does it lead to a lower field defect or an upper field defect?
Lower field defect. Likewise, lesions in the lower calcarine lead to upper field defects
What are the different ways to test visual fields?
- Perimetry (done with a computer) and Confrontation method (done with fingers)
