Superior Parietal Lobule

Anatomy

• Behind the postcentral sulcus, above the intraparietal sulcus (IPS); BA 5 and 7.
• Continues medially as the precuneus; the parieto-occipital sulcus lies posteriorly.
• The parietal station of the dorsal visual stream (“where / how”).
• Blood supply: watershed zone between MCA and ACA branches.

Functions

• Visuomotor integration: reaching, grasping, eye–hand coordination.
• Spatial attention (dorsal attention network — together with the FEF).
• Body schema and tracking of limb position.
• Mental rotation and visuospatial working memory.
• Representation of numerical magnitude (IPS — number sense).

Connections and chemistry

• Occipital cortex (dorsal stream)
• Frontal eye field and premotor cortex
• DLPFC (frontoparietal network)
• Pulvinar (thalamus)
• Cerebellum

Development

Developmental course through childhood and adolescence.

• The IPS specializes for numerical processing through childhood.
• Visuospatial working memory keeps developing into adolescence.

Clinical

• Dyscalculia: structural and functional differences in the IPS.
• Williams syndrome: dorsal stream and visuospatial difficulties.
• Turner syndrome: visuospatial and arithmetic difficulties (parietal).
• DCD and ADHD: visuomotor integration and attention networks.
• Large structural sample in OCD (ENIGMA-OCD): thinner inferior and superior parietal cortex in children (small effect); extends the view of OCD as a “frontal” disorder to the parietal cortex (ENIGMA-OCD, 2018). A

Treatment

This region from the perspective of medication, psychotherapy and neuromodulation. Letter badges are evidence levels.

• For visuospatial and visuomotor difficulties (Williams syndrome, Turner syndrome, DCD): occupational therapy, compensation with verbal strategies and school accommodations (e.g. a verbal step list for geometry and map tasks). C
• Number sense training for dyscalculia; details on the IPL card.

Assessment

Neuropsychological tasks and measures that probe this region's function.

• Mental rotation tasks
• Rey-Osterrieth Complex Figure (copy), WISC Block Design
• Corsi blocks, number line estimation

Lesions and damage

Clinical findings expected with damage or dysfunction.

• Optic ataxia: impaired reaching toward visual targets.
• Bálint syndrome (bilateral): simultanagnosia, optic ataxia, oculomotor apraxia.
• Contralateral neglect with right-sided lesions.

In the model

How this structure is defined in the 3D model, and the data source.

Superior parietal cortex.

References

Full citations for the card; links go to the paper (DOI) or a PubMed search.

1. ENIGMA-OCD Working Group. Am J Psychiatry 2018. Search PubMed