Subcortical Fibre Tracts

Question 1

Boundaries of frontal lobe

Answer 1

Dorsolateral surface: Central sulcus (posterior) and lateral/Sylvian fissure (inferior) Medial surface: corpus callosum (inferior) to central sulcus

Question 2

Boundaries of parietal lobe

Answer 2

Dosolateral surface: Anterior = central sulcus; Inferior = lateral sulcus; Posterior = upper half of arbitrary line connecting parieto-occipital sulcus to the pre-occipital notch Medial: Frontal lobe = anterior boundary; Parieto-occipital sulcus and corpus callosum = posterior and inferior boundaries

Question 3

Boundaries of temporal lobe

Answer 3

On lateral surface: 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 2. On medial surface•Posterior boundary: imaginary line joining the pre-occipital notch andt he anterior end of the calcarine sulcus

Question 4

Occipital lobe boundaries

Answer 4

1. On lateral surface•Anterior boundary = line joining the parieto-occipital sulcus and the pre-occipital notch On the medial surface:Anterior boundary = the posterior borders of the parietal and temporal lobes

Question 5

Which structures are found in limbic lobe?

Answer 5

1) cingulate gyrus; 2) parahippocampal gyrus 3) hippocampal formation

Question 6

What is the isthmus

Answer 6

Strip of cortex connecting parahippocampal gyrus to the cingulate gyrus

Question 7

What is BA4

Answer 7

Primary motor area -precentral gyrus, presntral sulcus, central sulcus)

Question 8

What is BA 6

Answer 8

premotor or motor association area

Question 9

What is inferior part of BA 8

Answer 9

Frontal eye field - cortical control of gaze

Question 10

What are BAs 3,1,2 involved in

Answer 10

Primary somatosensory cortex (post-central gyrus)

Question 11

What are BAs 5,7, and 40 involved in?

Answer 11

Somatosensory association area – superior parietal lobules extending to medial surface

Question 12

What are BAs 41 and 42 involved in?

Answer 12

Primary association area; superior surgface of superior temporal gyrus; Heschl’s gyrus

Question 13

BA 22 is involved in which sensation?

Answer 13

Audtion; secondary auditory cortex

Question 14

Which primary area is contained within BA 17?

Answer 14

Visual - in walls of calcarine fissure extending onto lateral surface

Question 15

Which BAs make up the visual association area?

Answer 15

BA 18 and BA 19

Question 16

Which BA is involved in taste?

Answer 16

BA 43

Question 17

Where is taste information integrated with olfactory info?

Answer 17

Orbital cortex of frontal lobe and amygdala

Question 18

Which BAs are involved in Broca’s Area?

Answer 18

44 and 45; inferior frontal/angular gyrus (usually left hemisphere)

Question 19

Which BAs are involved in Wernicke’s areas?

Answer 19

22 (superior temporal gyrus) and regions 39 and 40 around the end of the lateral sulcus into the parietal lobe

Question 20

Which fibre tract connects broca’s and wernicke’s

Answer 20

Arcuate fasciculus

Question 21

Which region is damaged in patients who have difficulty repeating words (conduction aphasia)

Answer 21

Arcuate fasciculus

Question 22

Which region is damaged in patients who have difficulty producing individual words, syntax, grammar

Answer 22

Broca’s

Question 23

Which region is damaged in patients who cannot comprehend speech and produce non-sensical wordcs

Answer 23

Wernicke’s

Question 24

Which region is characterized by BAs 9, 10, 11, and 12?

Answer 24

Frontal association - connected w/ DM thalamus

Question 25

Where do fibres from the upper visual field travel after reaching the lateral geniculate nucleus?

Answer 25

Lower bank of calcarine sulcus (V1)/BA17

Question 26

Where do fibres from the lower visual field travel after reaching the lateral geniculate nucleus?

Answer 26

Upper bank of calcarine sulcus (V1/BA17)

Question 27

Where are the frontal eye fields

Answer 27

Question 28

What lies posterior to the frontal eye field

Answer 28

Motor-hand area

Question 29

Which thalamic nucleus does auditory info from cochlea project to?

Answer 29

Medial geniculate nucleus

Question 30

What is heschl's gyrus

Answer 30

Contains A1; located transversely within lateral sulcus

Question 31

Within which cortex is the gustatory area?

Answer 31

Insular

Question 32

Which two lobes are involved in Wernickes area

Answer 32

Temporal and parietal

Question 33

What is the non-dominant hemisphere responsible for in language

Answer 33

Melody, prosody, accent, tone of voice

Question 34

Unimodal association cortex

Answer 34

Involved in higher-order processing of a single sensory of motor modality (e.g., SMA, sensory association area)

Question 35

Heteromodal association cortex

Answer 35

Involved in integrating functions from multiple modalities (e/g. sensory and motor)

Question 36

Are Broca's and Wernicke's hetero or uni-modal

Answer 36

Unimodal

Question 37

What are heteromodal areas?

Answer 37

Frontal, parietal, and temporal association areas

Question 38

Where do most commissural fibres cross the midline

Answer 38

Corpus callosum

Question 39

Which region of CC connects parietal and posterior frontal lobes?

Answer 39

Body

Question 40

Which region of the CC connects occipital lobes and posterior temporal lobes?

Answer 40

Splenium

Question 41

What does the genu of the CC connect?

Answer 41

2 frontal areas

Question 42

What are 3 commissural fibres?

Answer 42

1) CC; 2) anterior commissure; 3) posterior commissure

Question 43

What do association fibres connect?

Answer 43

Cortical regions in the same hemisphere (short connect adjacent gyri, long connect other regions like arcuate)

Question 44

Which fibres are in the anterior limb of the IC?

Answer 44

Corticopontine, thalamocortical (DM and Ant. nuclei)

Question 45

What is the blood supply to the ANTERIOR limb of the IC

Answer 45

Lenticulostriate arteries (deep branches from ACA and MCA)

Question 46

What fibres are carried in the genu of the IC?

Answer 46

Corticobulbar

Question 47

What is the blood supply to the genu of the IC?

Answer 47

Lenticulostriate (deep branches from MCA) and anterior choroidal

Question 48

What fibres are carried in the posterior limb of the IC?

Answer 48

corticopontine; corticospinal (localized) , thalamocortical (from VP, VL, VA)

Question 49

What is the blood supply to the posterior limb of the IC?

Answer 49

Lenticulostriate (deep branches from MCA); PCA, anterior choroidal

Question 50

What are projection fibres?

Answer 50

Fibres that originate in THALAMUS and project to cortex (via posterior IC) or originate in cortex and project to subcortical nuclei in the cerebral hemisphere, brainstem or spinal cord