Module 6: Cerebral Cortex Flashcards
What is the posterior and inferior boundary of the dorsolateral surface of the frontal lobe?
- Posterior boundary: central sulcus
- Inferior boundary: lateral sulcus
What is the posterior and inferior boundary of the medial surface of the frontal lobe?
• Posterior boundary: arbitrary line directed inferiorly from central
sulcus to corpus callosum
• Inferior boundary: corpus callosum
What are the anterior, posterior and inferior boundaries of the medial surface of the parietal lobe?
• anterior boundary: frontal lobe
• posterior and inferior boundaries: parieto-occipital sulcus and corpus
callosum
What are the anterior, posterior and inferior boundaries of the dorsolateral surface of the parietal lobe?
• Anterior boundary: central sulcus
• Inferior boundary: lateral sulcus and an arbitrary line directed
posteriorly from the lateral sulcus
• Posterior boundary: upper half of an arbitrary line connecting the
parieto-occipital sulcus with the pre-occipital notch
What are the posterior and superior boundaries of the lateral surface of the temporal lobe?
• Superior boundary: lateral sulcus and its posterior projection
• Posterior boundary: lower portion of arbitrary line connecting the
parieto-occipital sulcus and the pre-occipital notch
What is the posterior boundary of the medial surface of the temporal lobe?
• Posterior boundary: imaginary line joining the pre-occipital notch and
the anterior end of the calcarine sulcus
What is the anterior boundary of the lateral surface of the occipital lobe?
• Anterior boundary: line joining the parieto-occipital sulcus and the
pre-occipital notch
What is the anterior boundary of the medial surface of the occipital lobe?
• Anterior boundary: the posterior borders of the parietal and temporal
lobes
What three areas of cortex are included in the limbic lobe?
• Cingulate gyrus
• Parahippocampal gyrus - connected to cingulate gyrus by narrow
strip of cortex beneath the splenium of the corpus callosum - the
isthmus
• Hippocampal formation
What is the most common classification system used to describe the functional areas of the cortex?
Brodmann’s areas - uses numbers to indicate different functional areas based on their cytoarchitecture
What Brodmann areas are encompassed as motor areas?
4, 6, 8
What is the Brodmann area of primary motor area?
Primary motor area = precentral gyrus, precentral sulcus, central sulcus
4
What is the Brodmann area of premotor or motor association area (secondary motor area)?
Secondary motor area = anterior part of precentral gyrus and parts of superior, middle and inferior frontal gyri
6
What is the Brodmann area of the frontal eye fields?
FEF = control of lateral gaze
8
What connects Broca’s area to Wernicke’s area?
The arcuate fasciculus
What are the frontal association areas concerned with?
Complex aspects of behaviour (i.e., affect, personality, attention. They have extensive connections with dorsomedial (DM) nucleus of thalamus.
What comes anterior to the central sulcus?
Motor areas
What comes posterior to the central sulcus?
sensory areas
On this image of the medial brain, locate the:
- superior frontal gyrus
- Cingulate gyrus
- lingual gyrus
- fusiform gyrus
- parahippocampal gyrus
- uncus
On this image of the medial brain, locate the:
- cingulate sulcus
- parieto-occipital sulcus
- calcarine sulcus
What Brodmann numbers are associated with somatosensory areas?
primary somatosensory area: 1, 2, 3
somatosensory association area: 5, 7, 40
What Brodmann numbers are associated with auditory areas?
Primary autory area: 41, 42
Auditory association (secondary autditory area: 22
Where is the auditory association area (22)?
superior temporal gyrus and area posterior to primary auditory area in lateral
sulcus
Where is the primary auditory area (41,42)?
superior surface of superior temporal gyrus - Heschl’s gyri (convolutions); also called transverse temporal gyri
What Brodmann areas are associated with visual parts of the cortex?
Primary visual area: 17
Visual association (secondary visual) area: 18, 19
Note: areas 17, 18, 19 project to areas of parietal and temporal cortex for higher order vidual processing
Where is the primary visual area (17)?
In the walls of the posterior part of the calcarine sulcus, extending onto the lateral surface
Where is the secondary visual (visual association) area (18, 19)?
Surrounds the primary visual area on medial and lateral surfaces
What Brodmann numbers are associated with taste?
43 - primary taste area
Where is the primary taste area (43) located?
on insula and adjacent medial surface of parietal-frontal operculum - at base of central sulcus (Operculum = lid or cover)
Where are the secondary taste areas located?
Orbital cortex of frontal lobe and amygdala. Here taste information is integrated with olfactory information.
What Brodmann areas are associated with language?
Motor (expressive) area of Broca: 44, 45
Sensory (receptive) speech area of Wernicke: 22, 49, 40
Where is Broca’s area (44, 45) located?
part of inferior frontal gyrus of dominant hemisphere (usually left)
Where is Wernicke’s area (22, 39, 40) located?
includes posterior part of area 22 (superior temporal gyrus), with extensions around the posterior end of the lateral sulcus into the parietal region (areas 39 and 40) - dominant hemisphere
What is the cerebral cortex?
The cortex covers the entire surface of the brain, overlying the deep nuclei.
The cortex, together with these deep gray matter nuclei, comprise the forebrain
Of what two areas is the forebrain comprised?
- telencephalon
- diencephalon
Of what is the telencephalon comprised?
- cerebral hemispheres
- deep structures
Of what is the diencephalon comprised?
- thalamus
- hypothalmus
- subthalmus
What is another name for the precentral gyrus?
The primary motor area
On this medial image of the brain, locate the central sulcus
Why does describing the cortex based on lobes not generally provide an understanding of function?
Because the lobes of the brain are named after the bones of the skull
The cortex can be divided into two area, what are they?
Primary cortical areas
Association areas
What is the function of primary cortical areas?
To receive information from peripheral receptors (e.g., the thalamus), with little interpretation of the meaning of the information. These areas are concerned with receiving sensory information or executing motor tasks
What is the function of secondary cortical areas?
These areas receive input from the primary area and are involved in higher order processing, integrating, and interpreting information. These areas are located adjacent to primary areas.
Outflow from the primary motor area makes up what?
The corticospinal tract