Surface AnatomyIV - Heschl's Gyrus Flashcards
Auditory pathway
Cochlea Vestibular cochlea nerve Synapse Relay station Brain (Gyrus)
What is the functional importance of Heschl’s Gyrus?
Primary auditory area A1 (bilat)
What is Heschl’s Gyrus?
Gyri found in the area of primary auditory cortex buried within lateral sulcus of human brain, occupying brodmann area 41 + 42
What are landmark for Heschl’s Gyrus?
- Angriography
- Stereotaxy
- MR
- Planimetry
What is stereotaxy?
any technique that involves the recording and reproduction of three-dimensional haptic information or creating an illusion of depth to the sense of touch within an otherwise-flat surface
Axial Heschl’s Gyrus
Course: Anterolateral
Landmark: Adhaesio interthalamica
internal cerebral veins
Where is Heschl’s Gyrus located
Superior surface of the temporal lobe
Sagittal Gyrus
Shape: Omega (heart)
- S Intermedius of Beck
posterior border:
Heschl’s sulcus
What is Heschl’s Gyrus also known as?
Transverse temporal gyrus
Where is Heschl’s Gyrus hidden?
Within Slyvian fissure, with the planum temporale and superior temporal gyrus located lateral to it
Where is planum temporale larger?
Language dominant side
What is planum temporale?
- cortical area just posterior to the auditory cortex within sylvian fissure
- Triangular region which forms the heart of Wernicke’s area
- Most asymmetric region in the brain
Medial
Heschl’s Gyrus is seen at the back
Lateral
Heschl’s Gyrus moves anteriorly
Coronal Heschl’s Gyrus
Shape:
omega (medial)
Landmark: Tent-like shape of the fornices
What is the primary auditory cortex?
Cytoarchitectionic division of the cerebral cortex occupying the anterior transverse temporal gyrus in the back of lateral sulcus on dorsal surface of temporal lobe
Primary auditory cortex
First cortical destination of auditory information stemming from the thalamus
Neural activity in this brain . part correspond most strongly with the objective physical properties of a sound
What is Te1?
Primary hearing is located
What represents the primary auditory cortex?
Te1.1, Te1.0 and Te1.2 can be identified along the mediolateral axis of Heschl’s Gyrus
What is the direction of Heschl’s Gyrus ?
Postero-medial to antero-lateral
Where is the primary visual cortex located?
Calcarine sulcus
What is the area between calcarine sulcus and anterior calcarine sulcus?
Cuneus
What is the subdivision of calcarine sulcus?
Superior border = cuneus
Inferior border = lingual gyrus
What makes up the primary visual area?
- Cuneus
2. Lingual Gyrus
What is the parieto-occipital configuration of primary visual cortex?
Lazy Y
What is the calcarine sulcus pattern?
single peak or could be straight like a plateu
Double peak
S-shaped
Triple peaks
Variable
Where is myelination different?
Cortex bordering the calcarine sulcus
Different layering = different myelination
How much does the visual cortex encompass?
20% of the human brain
What does the visual cortex include?
Entire occipital lobe
Extending significantly into the parietal and temporal lobes
How many visual areas are there now?
8 visual areas
V1 to V8
How are each of these visual areas identified?
Based on evidence that suggests they contain a preserved representation of visual space which we refer as a cortical visual field map
Where is V4 located?
Fusiform gyrus
What do primary visual cortex (V1) contain?
Visual stria of Genari (striate cortex)
Extrastriate visual cortex (V2-V5)
Why is it not sufficient to use anatomical landmark to define visual regions?
Over or under estimate the size of V1 in a number of subjects
Beyond V1-V3
field maps are generally referred to as being dorsal, lateral or ventral to these regions.
It should be noted that due to an increase in receptive field sizes of neurons within these higher regions, the precision with which we can map the visual field using the travelling wave method becomes limited
V4
hV4/VO1 boundary in posterior transverse collateral sulcus (ptCoS)
Predicts location anatomically with >85% accuracy
V5
Visual area that identifies movement
Most of V5 in the depth of
Ant occipital sulcus
Anterior parts of inf lateral occipital or inf occipital sulcus.
