Parcellation Guide

 

Functional areas of the Dorsal Attention Network (DAN)

 

The DAN is network with bilateral functional areas that is involved in active holding of attention.

DAN_COR

ᐅ  Summary

Area 6a (6 anterior): part of the premotor areas. While the precise function of this area is unknown, the functions of the premotor cortex are well characterized in the literature. 6a shows greater activation when solving math problems, in social interaction settings, and when performing object feature comparison tasks.

ᐅ  Where is it?

Area 6a (6 anterior) makes up the posterior superior most bank of the superior frontal sulcus and the adjacent portions of the superior frontal gyrus, principally forming this bank just as the sulcus forms the right angle with the precentral sulcus.

ᐅ  What are its borders?

Area 6a borders areas 6d and 6mp posteriorly, and area 6ma medially. Its anterior border is made by s6-8, area 8AD, and i6-8. FEF is its inferior neighbor.

ᐅ What are its borders?

Area 6a demonstrates functional connectivity to area 2 in the sensory strip, areas SCEF, PEF, FEF, 6ma, 6mp, 6d, and 6v in the premotor regions, areas a24prime, p32prime, 5mv, and 23c in the middle cingulate regions, areas IFSa, IFJa, i6-8, 46, p9-46v and 9-46d in the lateral frontal lobe areas OP4, PFcm, FOP4, and FOP2 in the superior insula opercular regions, areas PoI1 and PoI2 in the lower opercula and Heschl's gyrus regions, areas TE2p, PHA3 and PHT in the temporal lobe, areas AIP, MIP, VIP, LIPd, LIPv, PFop, PF, PFt, PGp IP2, IP1, IP0, IPS1, 7AL,7PL, and 7PC, in the lateral parietal lobe, areas 7pm, 7am, DVT, and PCV in the medial parietal lobe, area V2 in the medial occipital lobe, and areas PH, TPOJ2, TPOJ3, and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area 6a is structurally connected to the pyramidal tracts and the parietal lobe. Connections to pyramidal tracts descend through the posterior limb of the internal capsule and cerebral peduncle to the brainstem. Parietal projections are portions of the SLF and connect with 3a, 3b, 7PC and 7AL. Local short association fibers connect with FEF, i6- 8, 55b, 8Av, 46 and 6r.

ᐅ What are its white matter connections?

Areas 6a and 6d are newly described subdivisions of the premotor cortex. While the precise function of these areas is unknown, the functions of the premotor cortex are well characterized in the literature. First, the premotor cortex is functionally divided into ventral and dorsal aspects. The dorsal premotor cortex is involved in associating informational cues with a particular body movement. These cues could be learned and arbitrary in nature or they can be based on other forms of somatosensation, such as visual or auditory sensation. The ventral premotor area is involved in hand movement manipulation of objects, e.g. when grasping or lifting. The ventral premotor area is also involved in more complex cortical functions such as when individuals learn actions or movements while observing others performing a task. Overall, the premotor cortex has significant function in the preparation of voluntary movements. Regarding area 6a more specifically, this region was distinguished from adjacent areas of the cortex based on differences in myelin thickness and functional activity.9 Compared to area s6-8, area 6a shows greater activation when solving math problems, in social interaction settings, and when performing object feature comparison tasks. Compared to area i6-8, area 6a shows greater activation in social interaction settings and relative deactivation in emotion identification and object feature comparison. Compared to area FEF, area 6a shows less activation in both gambling and object feature comparison.

 

6a_a

A: lateral-medial

 

6a_b

B: anterior-posterior

 

6a_c

C: superior-inferior

 

6a_dti

DTI image

ᐅ  Summary

Area 7Am (7 anterior-medial): part of the lateral parietal lobe regions. Involved in several types of information processing including space, vision shape and motion, working memory, and execution. The anterior portion of 7Am is involved in self-centered mental imagery and attentional processes. Relative to its posterolateral neighbor 7PL, area 7Am is less activated during working memory and auditory story tasks. Relative to its posteromedial neighbor 7Pm, area 7Am is less activated during working memory and shape recognition tasks.

ᐅ  Where is it?

Area 7AM (7 anterior-medial) is found on the anterosuperior surface of the medial face of the superior parietal lobule.

ᐅ  What are its borders?

Area 7AM borders the area 7AL superior-laterally, VIP posterolaterally, and areas 7PL and 7PM posteriorly. On its interhemispheric face, its anterior border is made up of areas 5L, and 5MV. Its inferior border is made up of PCV (precuneus visual area), and its posterior border is made up of area 7PM.

ᐅ What are its borders?

Area 7AM demonstrates functional connectivity to areas SCEF, FEF, PEF, 6ma, 6a, and 6r in the premotor regions, areas IFSa, 46, and 9-46d areas in the lateral frontal lobe, areas a24prime, a32prime, p32prime, 5mv, and 23c in the medial frontal lobe, areas MI, PoI1, PoI2, PFcm and FOP4 in the insula opercular regions, areas PHA3, PHT, and TE2p, in the temporal lobe, areas 7PC, 7AL, 7PL, AIP, VIP, MIP, LIPd, PFop, PFt, PF, PGp, IP2, and IP0 in the lateral parietal lobe, areas 7pm, PCV, POS2, and DVT in the medial parietal lobe, area V1 in the medial occipital lobe, areas V6 in the dorsal visual stream areas, area FFC in the ventral visual stream areas, and areas PH, TPOJ2, TPOJ3, and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area 7AM is structurally connected to the contralateral hemisphere and thalamus. Some individuals have IFOF connections but these tracts are inconsistent. Contralateral connections course through the corpus callosum to end at 7AM and 7Pm. Thalamic connections project inferior through the posterolateral thalamus to the brainstem and superior colliculus. Local association bundles connect with VIP and 7PL.

ᐅ What are its white matter connections?

Area 7AM is involved in several types of information processing including space, vision shape and motion, working memory, and execution. The anterior portion of 7AM is involved in self-centered mental imagery and attentional processes. Relative to its posterolateral neighbor 7PL, area 7AM is less activated during working memory and auditory story tasks. Relative to its posteromedial neighbor 7PM, area 7AM is less activated during working memory and shape recognition tasks.

 

7AM_a

A: lateral-medial

 

7AM_b

B: anterior-posterior

 

7AM_c

C: superior-inferior

 

7AM_dti

DTI image

ᐅ  Summary

Area 7PC (7 postcentral): part of the lateral parietal lobe regions. Involved in vision motion, observation, space, and execution. The left hemispheric portion of region 7PC is associated with imagination, and the right region is associated with vision shape, language comprehension, sexuality, and working memory. This region is involved in visual and somatosensory stimulation, and shows strong connection to somatosensory areas.

ᐅ  Where is it?

Area 7PC (7 postcentral) is found in the anterior, inferior superior parietal lobule. It extends into the adjacent posterior bank of the postcentral sulcus.

ᐅ  What are its borders?

Area 7PC borders Area 2 anteriorly and AIP inferiorly. Its posterior border is made up of LIPv and VIP. Area 7AL is its medial (superior) neighbor.

ᐅ What are its borders?

Area 7PC demonstrates functional connectivity to areas 1, 2, 3a, and 3b in the sensory strip, area 4 in the motor strip, areas SCEF, FEF, PEF 6ma, 6mp, 6a, 6d, 6r, and 6v in the premotor regions, areas 24dd, 24dv, p32prime, 5L, 5mv, and 23c in the medial frontal lobe, areas A4, PBelt, PFcm, FOP2, OP4, and OP1 in the insula opercular regions, areas PHT and TE2p, in the temporal lobe, areas 7PL, AIP, VIP, MIP, LIPv, LIPd, PFop, PFt, PGp, IP0, and IPS1 in the lateral parietal lobe, areas 7AM and DVT in the medial parietal lobe, area V2 in the medial occipital lobe, areas V3b, V6a, and V6 in the dorsal visual stream areas, area FFC in the ventral visual stream areas, and areas V3CD, V4t, PH, LO3, TPOJ2, TPOJ3, MST, and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area 7PC is structurally connected to local parcellations and the IFOF. Connections from the IFOF course through the posterior temporal gyrus and extreme/external capsule to the frontal lobe to 8BL, 6a, 6ma and SFL. The majority of individuals have IFOF projections but this tract is not present in everyone. Local short association bundles are abundant and connect with LIPd, LIPv, MIP, 1 and 2. Whitematter connections from 7PC in the right hemisphere have more consistent connections with the motor and somatosensory cortex.

ᐅ What are its white matter connections?

Area 7PC is involved in vision motion, observation, space, and execution. The left hemispheric portion of region 7PC is associated with imagination, and the right region is associated with vision shape, language comprehension, sexuality, and working memory. This region is involved in visual and somatosensory stimulation, and shows strong connection to somatosensory areas.

 

7PC_a

A: lateral-medial

 

7PC_b

B: anterior-posterior

 

7PC_c

C: superior-inferior

 

7PC_dti

DTI image

ᐅ  Summary

Area 7PL (7 posterior-lateral): part of the lateral parietal lobe regions. In the left hemisphere, this region is involved in vision motion, space, vision shape, attention, and working memory. In the right hemisphere, this region is involved in vision motion, space, vision shape, working memory, motor learning, execution, and attention. Area 7PL also plays a role in episodic memory retrieval and saccade- related activity. Relative to its inferomedial neighbor 7PM, area 7PL is activated vs deactivated when viewing body images vs a compilation of tool, face and place images. 7PL demonstrates greater functional activity in both emotional and social cue tasks compared to area 7PM.

ᐅ  Where is it?

Area 7PL (7 posterior-lateral) is found on the posterior superior surface of the superior parietal lobule.

ᐅ  What are its borders?

Area 7PL borders MIP laterally, VIP anteriorly, and areas 7AM and 7PM medially. Its posterior border is made up of small boundaries with IPS1, DVT and POS2.

ᐅ What are its borders?

Area 7PL demonstrates functional connectivity to areas SCEF, FEF, PEF, 6ma, 6a, and 6r in the premotor regions, areas IFSa, IFJp, p9-46v, 46, and 9- 46d in the lateral frontal lobe, areas p32prime, 5mv, and 23c in the medial frontal lobe, area FOP4 in the insula opercular regions, areas PHA3, PHT, and TE2p, in the temporal lobe, areas 7PC, 7AL, AIP, VIP, MIP, LIPd, LIPv, PFop, PFt, PF, IPS1, IP2, and IP0 in the lateral parietal lobe, areas 7AM, 7pm, PCV, and DVT in the medial parietal lobe, area V1 in the medial occipital lobe, areas V6 in the dorsal visual stream areas, area FFC in the ventral visual stream areas, and areas PH, TPOJ2, and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area 7PL is structurally connected to the IFOF, thalamus, MdLF and local parcellations. IFOF connections course through the posterior temporal lobe and extreme/external capsule to superior frontal gyrus parcellations 9p, 8BL and SFL. The MdLF terminates near the planum temporale at parcellation MBelt. Thalamic connections project inferior through the posterolateral thalamus to the brainstem and superior colliculus. The majority of local short association bundles project posterior to V3A, V7, IP0, MIP, PGp and IPS1, there are also connections to VIP, 7PL and 7A.

ᐅ What are its white matter connections?

The function of area 7PL in the left and right hemispheres is distinct. In the left hemisphere, this region is involved in vision motion, space, vision shape, attention, and working memory. In the right hemisphere, this region is involved in vision motion, space, vision shape, working memory, motor learning, execution, and attention. Area 7PL also plays a role in episodic memory retrieval and saccade-related activity. Relative to its inferomedial neighbor 7PM, area 7PL is activated vs deactivated when viewing body images versus a compilation of tool, face and place images. 7PL demonstrates greater functional activity in both emotional and social cue tasks compared to area 7PM.

 

7PL_a

A: lateral-medial

 

7PL_b

B: anterior-posterior

 

7PL_c

C: superior-inferior

 

7PL_dti

DTI image

ᐅ  Summary

Area AIP (anterior intraparietal): part of the lateral parietal lobe regions. Involved in grasping activity as well as object recognition. Neurons in this part of the cortex are oriented for grip and hand shape, and the inferior temporal cortex provides input related to object information. Receives input from the ventral and dorsolateral visual streams. Plays a role in shaping the hand for grasping activity. Beyond grasping action, is involved in tactile shape-processing and understanding orientation in space.

ᐅ  Where is it?

Area AIP (Anterior intraparietal) is found on the superior bank of the intraparietal sulcus at its most anterior aspect. It extends onto the superior surface of the adjacent superior parietal lobule, and its anterior tip lies in the bank of the postcentral sulcus.

ᐅ  What are its borders?

Area AIP borders Area 2 anteriorly and PFt anteroinferiorly. Its anterosuperior border is area 7PC, and its inferior border is with IP2 across the intraparietal sulcus. LIPv and LIPd make up its posterior boundaries.

ᐅ What are its borders?

Area AIP demonstrates functional connectivity to area 2 in the sensory strip, areas SCEF, FEF, PEF 6a, 6r, and 6ma in the premotor regions, areas IFSa, IFJp, 46, and p9-46v in the lateral frontal lobe, areas 5mv, and 23c in the medial frontal lobe, areas PoI2, FOP2, FOP4, and OP4 in the insula opercular regions, areas PHA3, PHT and TE2p, in the temporal lobe, areas 7PC, 7PL, 7AL, VIP, MIP, LIPv, LIPd, PFop, PFt, PGp, IP2, IP1, IP0, and IPS1 in the lateral parietal lobe, areas DVT, 7AM and 7pm in the medial parietal lobe, area V2 in the medial occipital lobe, area FFC in the ventral visual stream areas, and areas V3CD, PH, TPOJ2, and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area AIP is structurally connected to the pars opercularis and local parcellations. Connections from AIP to the pars opercularis travel anteroinferiorly to end at 43 and 6r. Local short association bundles connect with 2, PFt, PFcm, PF, IP2 and 7PC.

ᐅ What are its white matter connections?

Area AIP is involved in grasping activity as well as object recognition. Neurons in this part of the cortex are oriented for grip and hand shape, and the inferior temporal cortex provides input related to object information. AIP also receives input from the ventral and dorsolateral visual streams. This region also plays a role in shaping the hand for grasping activity. Beyond grasping action, AIP is involved in tactile shape-processing and understanding orientation in space.

 

AIP_a

A: lateral-medial

 

AIP_b

B: anterior-posterior

 

AIP_c

C: superior-inferior

 

AIP_dti

DTI image

ᐅ  Summary

Area FEF: part of the premotor areas. Known to be involved in rapid eye movements between fixed points, also known as intentional saccadic movements. Area FEF has also been implicated in smooth eye movements that allow the eyes to follow a moving target, also known as smooth pursuit eye movements. Together, these movements help the FEF to create a salience map for visual attention.

ᐅ  Where is it?

Area FEF is located on the anterior half of the precental gyrus, approximately half way down its length along the convexity, just inferior to the junction point of the precental and superior frontal sulci. It also forms the adjacent floor of the precentral sulci and straddles slightly onto the posterior edge of the middle frontal gyrus.

ᐅ  What are its borders?

Area FEF borders areas 6a and 6d superiorly and area 55b inferiorly. Area 4 is its posterior border and area i6-8 forms its anterior border on the middle frontal gyrus.

ᐅ What are its borders?

Area FEF demonstrates functional connectivity to area 2 in the sensory strip, areas SCEF, PEF, 6r, and 6v in the premotor regions, areas a24prime, p32prime, 5mv, and 23c in the middle cingulate regions, areas IFSa, IFJa, 46, and 9-46d in the lateral frontal lobe, areas 43, OP4, PFcm, FOP1, FOP3, FOP4, and FOP5 in the superior insula opercular regions, areas STV, LBelt, PBelt, A4, MI, 52, RI, PoI1 and PoI2 in the lower opercula and Heschl's gyrus regions, areas TE2p and PHT in the temporal lobe, areas AIP, MIP, VIP, LIPd, LIPv, PFop, PF, PFt, PGp, IP0, IPS1, 7AL,7PL, and 7PC, in the lateral parietal lobe, areas 7am, DVT, and PCV in the medial parietal lobe, areas V1, V2, V3 and V4 in the medial occipital lobe, areas V3a, V3b, V6, V6a, and V7 of the dorsal visual stream, areas V8 PIT, FFC, VVC, VMV1, VMV2, and VMV3 of the ventral visual stream, and areas V3cd, LO1, LO2, LO3, PH, TPOJ1, TPOJ2, TPOJ3, V4t, MST, and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area FEF is structurally connected to the contralateral hemisphere and superior longitudinal fasciculus. Contralateral connections course through the body of the corpus callosum to i6-8 and SFL. Connections with the superior longitudinal fasciculus connect FEF to the intraparietal sulcus and the inferior parietal lobe terminating at IP1, IP2 and PGs. Local short association fibers connect with 6d, 55b, i6-8, 8Av, 6a and PEF.

ᐅ What are its white matter connections?

Area FEF is known to be involved in rapid eye movements between fixed points, also known as intentional saccadic movements. Area FEF has also been implicated in smooth eye movements that allow the eyes to follow a moving target, also known as smooth pursuit eye movements. Together, these movements help the FEF to create a salience map for visual attention.

 

FEF_a

A: lateral-medial

 

FEF_b

B: anterior-posterior

 

FEF_c

C: superior-inferior

 

FEF_dti

DTI image

ᐅ  Summary

Area IFSa (inferior frontal sulcus, anterior): part of the lateral frontal lobe. Areas in the midventrolateral prefrontal cortex interact with posterior areas of the brain to retrieve specific auditory memories. The IFS also plays a specific role in creating procedural representations in working memory from verbal instructions.

ᐅ  Where is it?

Area IFSa is located at the anterior portion of the inferior frontal sulcus. It comprises part of the inferior bank of the MFG in its upper portions. It is superior to the pars orbitalis portion of the IFG.

ᐅ  What are its borders?

Area IFSa borders area p47r anterior and IFSp posteriorly. Its inferior border is area 45 and its superior border is made up of areas a9-46v, 46, and p9-46v.

ᐅ What are its borders?

Area IFSa demonstrates functional connectivity to areas a47r, p47r, IFSp, IFJa, IFJp, a9-46v, p9-46v, and 46 in the dorsolateral frontal lobe, areas 8BM and 33prime in the medial frontal lobe, areas 6ma, 6a, 6r, PEF, and FEF in the premotor areas areas FOP4, FOP5, PFop, MI and PoI2 in the insula opercular area, area 11L in the orbitofrontal region, areas PH, PHT, TE1p, TE2p PeEc, and PHA3 in the temporal lobe, areas 7PL, IP0, IP1, IP2, PF, PGp, PFt, AIP, MIP, and LIPd in the inferior parietal lobe, and areas 7am and 23c in the medial parietal lobe.

ᐅ What are its functional connections?

Area IFSa is structurally connected with the arcuate/SLF and surrounding parcellations. Connections with the arcuate/SLF project posteriorly and wrap around the Sylvian fissure to the inferior temporal gyrus to end at TE2a, there are also connections from the arcuate/SLF that end at 4. Local short association bundles connect with p47r, 46, p9-46v, 45, IFSa, 8C, 44, IFSp and p47r, a9-46.

ᐅ What are its white matter connections?

Areas in the midventrolateral prefrontal cortex interact with posterior areas of the brain to retrieve specific auditory memories. The IFS also plays a specific role in creating procedural representations in working memory from verbal instructions.

 

IFSa_a

A: lateral-medial

 

IFSa_b

B: anterior-posterior

 

IFSa_c

C: superior-inferior

 

IFSa_dti

DTI image

ᐅ  Summary

Area LIPd (lateral intraparietal, dorsal): part of the lateral parietal lobe regions. Implicated in control of attention and eye movements. This region has specifically been implicated in saccade coordination and mapping of contralateral spaces.

ᐅ  Where is it?

Area LIPd (Lateral intraparietal, dorsal) is located centrally on the superior bank of the intraparietal sulcus. Note that the nomenclature here can be confusing. LIPd is actually ventral to LIPv.

ᐅ  What are its borders?

Area LIPd borders AIP anteriorly, and MIP posteriorly. Its inferior border (across the intraparietal sulcus) is made up of IP2 and IP1. Its superior border is made up of LIPv and VIP.

ᐅ What are its borders?

Area LIPd demonstrates functional connectivity to areas SCEF, FEF, PEF 6a, and 6r in the premotor regions, areas IFSa, IFSp, IFJa, p47r, i6-8, 8C, 9- 46d, 46, a9-46v,and p9-46v in the lateral frontal lobe, areas 8BM, p32prime, 5mv, and 23c in the medial frontal lobe, areas PoI2, FOP4, FOP5, MI, AVI and PoI2 in the insula opercular regions, areas PHA3, PHT and TE1p, in the temporal lobe, areas 7PC, 7PL, AIP, VIP, MIP, LIPv, PF, PGp, IP2, IP1, IP0, and IPS1 in the lateral parietal lobe, areas PCV, DVT, 7AM and 7pm in the medial parietal lobe, areas V1, V2 and V3 in the medial occipital lobe, and areas PH and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area LIPd is structurally connected to the premotor region and local parcellations. In some individuals the anterior projections from LIPd end at the motor cortex and do not extend to premotor areas. Premotor connections end at 55b and PEF. Local short association bundles connect with PGs, AIP, IP1, IP2 and PGs.

ᐅ What are its white matter connections?

LIPd is implicated in control of attention and eye movements. This region has specifically been implicated in saccade coordination and mapping of contralateral spaces.

 

LIPd_a

A: lateral-medial

 

LIPd_b

B: anterior-posterior

 

LIPd_c

C: superior-inferior

 

LIPd_dti

DTI image

ᐅ  Summary

Area LIPv (lateral intraparietal, ventral): part of the lateral parietal lobe regions. implicated in control of attention and eye movements, and is important during visually guided reaching and pointing, hand movements, and change in visuomotor contingencies.

ᐅ  Where is it?

Area LIPv (Lateral intraparietal, ventral) is found on the inferior edge of the superior parietal sulcus. Note that it does not enter the banks of the intraparietal sulcus, but instead is located on the upper surface of the superior parietal lobule.

ᐅ  What are its borders?

Area LIPv borders AIP and area 7PC anteriorly, VIP superiorly, LIPv laterally, and MIP posteriorly.

ᐅ What are its borders?

Area LIPv demonstrates functional connectivity to areas 1 and 2 in the sensory strip, area 4 in the motor strip, areas SCEF, FEF, PEF 6a, 6r, and 6v in the premotor regions, areas p32prime, 5mv, and 23c in the medial frontal lobe, area FOP4 in the insula opercular regions, areas PHT and TE2p, in the temporal lobe, areas 7PC, 7PL, AIP, VIP, MIP, LIPv, PFop, PFt, PGp, IP0, and IPS1 in the lateral parietal lobe, area DVT in the medial parietal lobe, areas V1,V2, V3, and V4 in the medial occipital lobe, areas V3a, V3b, V7, V6a, and V6 in the dorsal visual stream areas, area V8, PIT, FFC, VVC, VMV1, VMV2, and VMV3 in the ventral visual stream areas, and areas V3CD, V4t, PH, LO1, LO2, LO3, TPOJ2, MT, MST, and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area LIPv is structurally connected to local parcellations. Local short association bundles connect with 2, AIP, 7PC, IP2, LIPd, LIPv and MIP. White matter tracts from LIPv in the right hemisphere have more consistent connections with the IFOF. However, this tract is not present in all individuals.

ᐅ What are its white matter connections?

LIPv is implicated in control of attention and eye movements, and is important during visually guided reaching and pointing, hand movements, and change in visuomotor contingencies.

 

LIPv_a

A: lateral-medial

 

LIPv_b

B: anterior-posterior

 

LIPv_c

C: superior-inferior

 

LIPv_dti

DTI image

ᐅ  Summary

Area MST (medial superior temporal) part of the lateral surface areas of the occipital lobe. Receives direct, functional input from area MT and is responsible for the integration and analysis of global, visual motion and the perception of self-motion. Involved in the execution and continuation of smooth pursuit eye movements, in coordination with the frontal eye fields.

ᐅ  Where is it?

Area MST (medial superior temporal area) is a vertically oriented area found paralleling and just anterior to MT

ᐅ  What are its borders?

just below the angular gyrus.

ᐅ What are its borders?

Area MST borders MT posteriorly

ᐅ What are its functional connections?

and FST anteriorly. Its superior border is made up of TPOJ2 and TPOJ3. Its inferior border is formed by FST and V4t.

ᐅ What are its white matter connections?

Area MST demonstrates functional connectivity to areas 1

 

MST_a

A: lateral-medial

 

MST_b

B: anterior-posterior

 

MST_c

C: superior-inferior

 

MST_dti

DTI image

ᐅ  Summary

Area MT (middle temporal): part of the lateral surface areas of the occipital lobe. Neurons respond to direction-sensitive visual motion and are responsible for the integration of one-dimensional visual signals into a two- dimensional visual motion pattern, binocular disparity tuning, noise reduction, segmentation of figure and background in complex and moving stimuli, and initiation of smooth-pursuit eye movements.

ᐅ  Where is it?

Area MT (Middle temporal area) is a vertically oriented area in the superior part of the central lateral occipital lobe. It is located just inferior to the angular gyrus.

ᐅ  What are its borders?

Area MT borders LO3 posteriorly, and MST anteriorly. Its superior border is formed by TPOJ3 and its inferior border by V4t.

ᐅ What are its borders?

Area MT demonstrates functional connectivity to areas 1,2,3a, and 3b in the sensory strip, area 4 in the motor strip, areas OP4, RI, PBelt, A4, and A5 in the insula and opercular region, areas VIP, LIPv, and IPS1 in the parietal lobe, areas V2, V3, and V4 in the medial occipital lobe, areas V3a, V3b, V7, V6, and V6a of the dorsal visual stream, areas FFC, VVC, V8, PIT, VMV3 of the ventral visual stream, and areas V3cd, V4t, MST, LO1, LO2, LO3, PH, and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area MT is structurally connected with the ILF. These projections are inconsistent across brains. ILF projections travel through the temporal lobe to end at TF. There are many short association bundles connecting to MST, LO1, LO2, LO3, TPOJ2, TPOJ3, FST, PH, V3b and IPO.

ᐅ What are its white matter connections?

Neurons in area MT respond to direction-sensitive visual motion and are responsible for the integration of one-dimensional visual signals into a two- dimensional visual motion pattern, binocular disparity tuning, noise reduction, segmentation of figure and background in complex and moving stimuli, and initiation of smooth-pursuit eye movements.

 

MT_a

A: lateral-medial

 

MT_b

B: anterior-posterior

 

MT_c

C: superior-inferior

 

MT_dti

DTI image

ᐅ  Summary

Area PEF: part of the premotor areas. Known to be involved in reflexive eye movements, also called reflexive saccades.

ᐅ  Where is it?

Area PEF (premotor eye field) is a small area located in the floor of the precentral sulcus at the junction of the precentral and inferior frontal sulci. It spills slightly onto the adjacent precentral gyrus and unlike FEF and area 55b, it is mostly vertically oriented.

ᐅ  What are its borders?

Area PEF borders area 55b superiorly and area 6r inferiorly. Area 6v is its posterior border and areas 8C and IFJp form its anterior border on the MFG and in the inferior frontal sulcus respectively.

ᐅ What are its borders?

Area PEF demonstrates functional connectivity to areas SCEF, FEF, 6ma, 6r, 6a, and 6v in the premotor regions, areas a24 prime, p32prime, and 23c in the middle cingulate regions, areas IFSa, IFJp, and 9-46d in the lateral frontal lobe areas 43, PFcm, FOP4, and FOP5 in the superior insula opercular regions, areas MI and PoI2 in the lower opercula and Heschl's gyrus regions, areas TE2p,and PHT in the temporal lobe, areas AIP, MIP, LIPd, LIPv, PFop, PFt, PGp, IP0, 7PL, and 7PC, in the lateral parietal lobe, are a 7am in the medial parietal lobe, and areas PH and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area PEF is structurally connected to the superior longitudinal fasciculus. PEF does have connections to the contralateral hemisphere but this is inconsistent across individuals. Connections with the superior longitudinal fasciculus connect 55b to inferior parietal lobe parcellations PHT, TPOJ2, FST and PFm. Local short association fibers connect with 6r, 8C and IFJp.

ᐅ What are its white matter connections?

Area PEF is known to be involved in reflexive eye movements, also called reflexive saccades.

 

PEF_a

A: lateral-medial

 

PEF_b

B: anterior-posterior

 

PEF_c

C: superior-inferior

 

PEF_dti

DTI image

ᐅ  Summary

Area PF (parietal area f): part of the lateral parietal lobe regions. Important in the action observation and imitation network and has been implicated in the mirror neuron system. Activated when individuals observe the use of tools to move objects.

ᐅ  Where is it?

Area PF (parietal area F) is found on the lateral surface of the superior portion of the supramarginal gyrus.

ᐅ  What are its borders?

Area PF borders PSL and PFcm inferiorly, PFop and PFt anteriorly, IP2 superiorly, and PFM posteriorly.

ᐅ What are its borders?

Area PF demonstrates functional connectivity to areas SCEF, FEF, 6ma, 6a, and 6r in the premotor regions, areas a24prime, p24prime, p32prime, 5mv, and 23c in the middle cingulate regions, areas IFSa, IFJp, a9-46v, p9-46v, 46, and 9-46d in the lateral frontal lobe, areas OP4, PFcm, FOP1, FOP3, and FOP5 in the superior insula opercular regions, areas AVI, MI, 52, PoI1 and PoI2 in the lower opercula and Heschl's gyrus regions, area PHT in the temporal lobe, areas PFt, PFop, PGp, IP0, IP2, AIP, MIP, LIPd, 7PL, and 7AL in the lateral parietal lobe, areas 7AM, PCV, and DVT in the medial parietal lobe, and area V1 in the medial occipital lobe.

ᐅ What are its functional connections?

Area PF is structurally connected to the arcuate/SLF and local parcellations. Arcuate/SLF connections course anteriorly from PF to somatosensory areas 1, 3a, 4, 43 and OP4, and inferiorly to middle and inferior temporal gyrus parcellations TE1a, STSva and TE2a. Local short association bundles connect with AIP, PFcm, PFm, PFop, PFt, PSL and STV.

ᐅ What are its white matter connections?

PF has functions similar to those localized to area PFt. It is important in the action observation and imitation network and has been implicated in the mirror neuron system described above. It is also activated when individuals observe the use of tools to move objects.

 

PF_a

A: lateral-medial

 

PF_b

B: anterior-posterior

 

PF_c

C: superior-inferior

 

PF_dti

DTI image

ᐅ  Summary

Area PFt (parietal area F, part t): part of the lateral parietal lobe regions. Important in the action observation and imitation network as well as in grasping objects under visual guidance. Also implicated in the mirror neuron system, and activated when individuals observe the use of tools to move objects.

ᐅ  Where is it?

Area PFt (parietal area F, part t) is found on the posterior bank of the postcentral sulcus, on the anterosuperior edge of the inferior parietal lobule. It lies on the inferior edge of the intraparietal sulcus, just where it meets the postcentral sulcus.

ᐅ  What are its borders?

Area PFt borders AIP superiorly, and PFop inferiorly. Area 2 is its anterior neighbor, and area PF is its posterior neighbor.

ᐅ What are its borders?

Area PFt demonstrates functional connectivity to areas 1 and 2 in the sensory strip, areas SCEF, FEF, PEF, 6ma, 6mp, 6a, 6d, 6r, and 6v in the premotor regions, areas p32prime, 5mv, and 23c in the middle cingulate regions, areas IFSa, IFJp, and 46 in the lateral frontal lobe, areas OP4, OP1, PFcm, FOP2, and FOP4 in the superior insula opercular regions, areas MI, PoI1 and PoI2 in the lower opercula and Heschl's gyrus regions, area PHA3 and PHT in the temporal lobe, areas PFop, PF, PGp, IP2, IP0, IPS1, AIP, VIP, MIP, LIPv, LIPd, 7PC, 7PL, and 7AL in the lateral parietal lobe, area 7AM in the medial parietal lobe, area FFC in the ventral visual stream, and areas PH, and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area PFt is structurally connected to local parcellations, the inferior parietal lobule and opercular parcellations through the arcuate/superior longitudinal fasciculus (SLF). Connections from PFt project diagonally to the inferior parietal lobule and anterior inferior to the operculum. Operculum projections end at OP4, 43, 6r and 4. Inferior parietal projections end at 2 and AIP. Local short association bundles are PF and PFop

ᐅ What are its white matter connections?

Area PFt is important in the action observation and imitation network as well as in grasping objects under visual guidance. This region is also implicated in the mirror neuron system described above. PFt is also activated when individuals observe the use of tools to move objects.

 

PFt_a

A: lateral-medial

 

PFt_b

B: anterior-posterior

 

PFt_c

C: superior-inferior

 

PFt_dti

DTI image

ᐅ  Summary

Area PH: part of the lateral surface areas of the occipital lobe. Higher level holistic perception region of the visual system that acts as a hub of ventral stream input, integrating place-specific" information

ᐅ  Where is it?

Area PH is a horizontally oriented area in the anteroinferior lateral occipital lobe. It is roughly in line with the ITG and is mostly lateral to the occipito-temporal sulcus, which it forms a small portion of its lateral bank. Thus, it spills onto the basal surface slightly.

ᐅ  What are its borders?

Area PH borders TE1p and TE2p anteriorly, and LO2 and PIT posteriorly. FFC is its medial neighbor on its basal surface. Its superior border is made up of parts of TE1p, PHT and FST.

ᐅ What are its borders?

Area PH demonstrates functional connectivity to areas 1,2, and 3a in the sensory strip, area 4 in the motor strip, areas SCEF, FEF, PEF, 6r, 6v, and 6a, in the premotor region, areas p9-46v, IFSa, IFSp, IFJa, and IFjp in the lateral frontal lobe, areas 23c, and5mv in the cingulate regions, areas PoI2, LBelt, PBelt, and A4 in the insula and opercular region, areas PeEc, PHA3, TE2p and PHT, in the temporal lobe, areas 7PC, 7PL, 7am, PGp, PFop, PF, AIP, MIP, VIP, LIPd, LIPv, DVT, IP2, IP0, and IPS1 in the parietal lobe, areas V1, V2, V3, and V4 in the medial occipital lobe, areas V3a, V3b, V7, V6, and V6a of the dorsal visual stream, areas FFC, VVC, V8, PIT, VMV1, VMV2, VMV3 of the ventral visual stream, and areas TPOJ2, TPOJ3, MT, MST, V3cd, V4t, MT, LO1, LO2, LO3, and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area PH is structurally connected to the SLF and ILF. SLF projections are consistent across brains and terminate at 44 and 45. ILF projections are also consistent travel through the temporal lobe to end at TGv and TGd. Short association bundles are connected to FST, MST, MT, PHT, V4T, and TE1p.

ᐅ What are its white matter connections?

Area PH is a higher-level holistic perception region of the visual system that acts as a hub of ventral stream input, integrating "place-specific" information, while showing little to no activity to objects or faces. Using these data, area PH encodes a representation of the local scene and, due to its location, allows it to be remembered and subsequently recognized, implicating it in the formation of spatial maps, place encoding and place recognition.

 

PH_a

A: lateral-medial

 

PH_b

B: anterior-posterior

 

PH_c

C: superior-inferior

 

PH_dti

DTI image

ᐅ  Summary

Area PHT (parahippocampal temporal): part of the temporal lobe regions. Involved in processes related to the controlled retrieval of conceptual knowledge, while the anterior gyrus is involved in the automatic retrieval of specific semantic information. In contrast to the other areas of the lateral temporal cortex and temporal pole, that are all strongly associated with the task negative network, PHT is strongly associated with the task positive network. In addition, PHT (like TE1p anteriorly) is deactivated during language recognition tasks.

ᐅ  Where is it?

Area PHT is found on the anterior portions of the subcentral gyrus (where the precentral and postcentral gyri meet just below the central sulcus). It involves the lateral surface of that operculum as well as the inferior surface which faces the Sylvian Fissure.

ᐅ  What are its borders?

Area PHT borders area 6r anteriorly and OP4 posteriorly. Its superior border includes area 6v, as well as areas 4 and 3a. Its inferior borders include FOP1 and FOP2.

ᐅ What are its borders?

Area PHT demonstrates functional connectivity to areas IFSa, IFJa, IFJp, 6a,6ma, 6r, 46, 9-46d, p9-46v, p47r, FEF, PEF, SCEF, a24prime, p24prime, p32prime, 33prime, 23c, and 5mv in the frontal lobe, areas FOP1, FOP3, FOP4, FOP5, 43, PFcm, 52, MI, PoI1, and PoI2 in the insula opercular area, areas TE1p, TE2p and PHA3 in the temporal lobe, areas AIP, MIP, VIP, LIPv, LIPd, IPS1, IP0, IP1, IP2, PF, PFop, PFt, PGp, 7PC, 7pm, 7AL, 7PL, PCV and DVT in the parietal lobe, and areas V1, V2, FST, PH, TPOJ2 in the occipital lobe.

ᐅ What are its functional connections?

Area PHT is structurally connected to the arcuate/SLF. Arcuate/SLF tracts wrap around the Sylvian fissure projecting toward the frontal lobe and turn medially to end at 44, IFJa, IFJp and IFSp. There are abundant posterior projections from the arcuate/SLF that terminate at the inferior parietal lobule at PGs, STV, PFm, PGi, TPOJ1 and TPOJ2.

ᐅ What are its white matter connections?

Area PHT lies in the posterior MTG leading into the angular gyrus. The posterior MTG is involved in processes related to the controlled retrieval of conceptual knowledge, while the anterior gyrus is involved in the automatic retrieval of specific semantic information. In contrast to the other parcellations of the lateral temporal cortex and temporal pole (TE1p, TE1m, TE1a, TE2p, TE2a, TGv, TGd, and TF) which are all strongly associated with the task negative network, PHT is strongly associated with the task positive network. In addition, PHT (like TE1p anteriorly) is deactivated during language recognition tasks.

 

PHT_a

A: lateral-medial

 

PHT_b

B: anterior-posterior

 

PHT_c

C: superior-inferior

 

PHT_dti

DTI image

ᐅ  Summary

Area TE2p (temporal area 2 posterior): part of the temporal lobe regions. Appears primarily related to visual pathways. Relative to TE2a, TE2p is more active in theory of mind tasks and motor tasks. Notably, compared to the other TE1 and TE2 regions which are deactivated in the TOOL-AVG contrast, TE2p is activated unilaterally on the left in TOOL-AVG, demonstrating a possible role in object recognition.

ᐅ  Where is it?

Area TE2p (TE 2 posterior) is found in the posterior part of the occipital temporal sulcus and the middle posterolateral portion of the fusiform gyrus.

ᐅ  What are its borders?

Area TE2p borders PH posteriorly, and FFC medially. Its anterior border is TF and its lateral border is made up of TE2a, and TE1p.

ᐅ What are its borders?

Area TE2p demonstrates functional connectivity to areas FEF, PEF, IFSa, IFJa, IFJp, p9-46v, 6a, and 6r in the frontal lobe, area PoI2 in the insula, area PHT in the temporal lobe, areas PGp, AIP, MIP, LIPv, LIPd, IPS1, IP0, PFop, 7PC, 7PL, 7AL in the parietal lobe, and areas PH, FFC, FST, TPOJ2, and TPOJ3 in the occipital lobe.

ᐅ What are its functional connections?

Area TE2p is structurally connected to the arcuate/SLF and local parcellations. White matter tracts of this parcellation are variable across individuals. Arcuate/SLF tracts wrap around the Sylvian fissure projecting toward the frontal lobe. The termination of the arcuate/SLF is unable to be delineated, as the tracts cannot be traced to specific parcellations. Local short association fibers connect to FFC, PH, TE2p, FFC, TE1m, TF and TE2a. White matter tracts in the right hemisphere of TE2p have consistent occipital connections.

ᐅ What are its white matter connections?

The function of area TE2p appears primarily related to visual pathways. Relative to TE2a, TE2p is more active in theory of mind tasks and motor tasks. Notably, compared to the other TE1 and TE2 regions which are deactivated in the TOOL-AVG contrast, TE2p is activated unilaterally on the left in TOOL-AVG, demonstrating a possible role in object recognition.

 

TE2p_a

A: lateral-medial

 

TE2p_b

B: anterior-posterior

 

TE2p_c

C: superior-inferior

 

TE2p_dti

DTI image

ᐅ  Summary

Area V4t (visual area 4t): part of the lateral surface areas of the occipital lobe. Shown in the literature to integrate information from both the ventral and dorsal streams, and demonstrates a high level of activity in response to both motion and shape-sensitive information, indicating its significance in the integration of object processing and global-motion perception.

ᐅ  Where is it?

Area V4t (Visual area 4t) is a horizontal area in the central portion of the lateral occipital cortex.

ᐅ  What are its borders?

Area V4t borders LO1 posteriorly, and FST anteriorly. Its inferior border is LO2. Its superior border is made up of MT, MST, and LO3.

ᐅ What are its borders?

Area V4t demonstrates functional connectivity to areas 1,2,3a, and 3b in the sensory strip, area 4 in the motor strip, area FEF in the premotor region, areas RI, PBelt, and A4 in the insula and opercular region, areas VIP, LIPv, and IPS1 in the parietal lobe, areas V2, V3, and V4 in the medial occipital lobe, areas V3a, V3b, V7, V6, and V6a of the dorsal visual stream, areas VVC, V8, VMV1, VMV2, and VMV3 of the ventral visual stream, and areas V3cd, MT, MST, LO3, PH, and FST of the lateral occipital lobe.

ᐅ What are its functional connections?

Area V4t is structurally connected with local parcellations. Tracts originating from this region such as SLF and ILF are inconsistent across brains. Short association bundles are connected to V4t, LO3, MST, MT, LO1 and V3CD.

ᐅ What are its white matter connections?

Area V4t has been shown in the literature to integrate information from both the ventral and dorsal streams, and demonstrates a high level of activity in response to both motion and shape-sensitive information, indicating its significance in the integration of object processing and global-motion perception.

 

V4t_a

A: lateral-medial

 

V4t_b

B: anterior-posterior

 

V4t_c

C: superior-inferior

 

V4t_dti

DTI image

ᐅ  Summary

Area VIP (ventral intraparietal): part of the lateral parietal lobe regions. Demonstrates directional selectivity. It is activated by optic flow and assists in encoding direction. This region is important for visual motion detection, auditory movements, and vestibular and tactile movement processing.

ᐅ  Where is it?

Area VIP (ventral intraparietal) is found on the central portion of superior surface of the superior parietal lobule. It does not extend to the intraparietal sulcus, though it does approach the interhemispheric fissure.

ᐅ  What are its borders?

Area VIP borders LIPv and MIP laterally, areas 7AL and 7PC anteriorly, area 7AM medially, and area 7PL posteriorly.

ᐅ What are its borders?

Area VIP demonstrates functional connectivity to areas 1 and 2 in the sensory strip, area 4 in the motor strip, areas SCEF, FEF, 6a, and 6v in the premotor regions, area FOP4 in the insula opercular regions, area PHT in the temporal lobe, areas 7PC, 7PL, 7AL, AIP, VIP, MIP, LIPv, LIPd, PGp, IP0, and IPS1 in the lateral parietal lobe, area DVT in the medial parietal lobe, areas V2, V3, and V4 in the medial occipital lobe, areas V3a, V3b, V7, V6a, and V6 in the dorsal visual stream areas, area V8, PIT, FFC, VVC, VMV1, VMV2, and VMV3 in the ventral visual stream areas, and areas V3CD, V4t, PH, LO1, LO2, LO3, MT, MST, and FST in the lateral occipital lobe.

ᐅ What are its functional connections?

Area VIP is structurally connected to the MdLF, IFOF, thalamus and local parcellations. IFOF connections course through the posterior temporal lobe and extreme/external capsule to superior frontal gyrus parcellations 9p, 8BL and SFL. MdLF connections project inferior, deep to the parietal lobe to the planum temporale to end at MBelt. Thalamic connections project inferior through the posterolateral thalamus to the brainstem and superior colliculus. Local short association bundles connect with 7AL, 7AM, 7PL, MIP and LIP.

ᐅ What are its white matter connections?

Area VIP demonstrates directional selectivity. It is activated by optic flow and assists in encoding direction. This region is important for visual motion detection, auditory movements, and vestibular and tactile movement processing.

 

VIP_a

A: lateral-medial

 

VIP_b

B: anterior-posterior

 

VIP_c

C: superior-inferior

 

VIP_dti

DTI image

The information provided in this guide has been adapted from 'A Connectomic Atlas of the Human Cerebrum' (Briggs et al, 2018).
 
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