Parietal Cortex — Function, Location & Quiz

The parietal cortex is where sensation becomes a usable map for attention and action. It combines information across modalities rather than serving as a second primary sensory strip, which is why its lesions disturb space, calculation or skilled action in ways that intact eyes and muscles cannot explain.

Laterality is the high-yield distinction. Right parietal injury is strongly associated with neglect of left space, while dominant left parietal injury can disrupt symbolic skills and produce the cluster known as Gerstmann syndrome.

Test this anatomy in the Lesion Localization Quiz or open the interactive 3D brain model.

Location and anatomical map

Spatial awareness, attention, sensory integration, numeracy.

Atlas category: cortical. Brodmann areas or landmark: BA 5, 7 (superior parietal), BA 39, 40 (inferior parietal).

Functions

  • Spatial awareness and visuospatial processing
  • Attention — especially orienting and disengaging
  • Sensory integration — combining visual, auditory, somatosensory
  • Numerical cognition and mental arithmetic
  • Tool use and action understanding

Pathways and connections

  • Dorsal stream terminus ('where/how' pathway from V1)
  • Parietal ↔ Frontal (frontoparietal attention network)
  • Parietal ↔ Temporal (ventral attention for reorienting)

Clinical relevance

  • Right parietal lesion → hemispatial neglect (ignore left side of space)
  • Bilateral parietal → Balint's syndrome (simultanagnosia, optic ataxia, ocular apraxia)
  • Gerstmann syndrome (dominant parietal): agraphia, acalculia, finger agnosia, left-right confusion
  • Ideomotor apraxia — can't pantomime tool use despite intact motor function

Key facts

  • Intraparietal sulcus (IPS) contains neurons tuned to numerosity
  • Corbetta & Shulman: dorsal attention network (top-down) vs. ventral attention (bottom-up surprise)
  • Posterior parietal cortex is where vision meets action — critical for reaching and grasping

Exam tip

Right parietal = SPACE (neglect). Left parietal = SYMBOLS (language, math, praxis). Know the lateralization!

Common questions

What does the parietal cortex do?

It supports spatial awareness, attention, multisensory integration, numerical cognition and the transformation of visual information into reaching or tool-use actions.

Why does a right parietal lesion cause neglect?

Right parietal attention systems are crucial for representing space. Damage can make the patient fail to attend to the left side even though early visual and sensory pathways may still carry information.

What is Gerstmann syndrome?

It is a dominant parietal syndrome classically combining agraphia, acalculia, finger agnosia and left-right confusion, often associated with the left angular gyrus.