Superior parietal lobule

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Superior parietal lobule

The superior parietal lobule is an anatomical subdivision of the parietal lobe of the cerebrum. It is also referred to as the cortical sensitive secondary field , since it takes on the neurophysiological task of the association center with regard to the somatosensitive cortex .

topography

  • Superior parietal lobule

  • Precuneus

The parietal lobule is superior to the convex brain area adjacent to medial to the longitudinal fissure and passes on the medial side in the precuneus above, according to the rostral in at the jacket edge located part of the postcentral gyrus . Laterally it is bounded by the intraparietal sulcus .

Somatotopia

In contrast to the somatosensitive cortex, the superior parietal lobule is not segmented or somatotopically structured. It represents the contralateral half of the body.

links

There are no direct afferent projection trajectories (i.e. no primary fibers). Only secondary potentials can be derived here , which do not allow any assignment to specific sense organs. Therefore, conclusions can only be drawn from failure symptoms as a result of localized damage. Apart from the primary main field in the somatosensory cortex, afferents only come from the nucleus dorsalis thalami . In contrast to the damage that is closer to the central sulcus , which causes a disturbance of the surface sensitivity, damage to the superior parietal lobule affects deep sensitivity .

physiology

The task of the association center in the superior parietal lobule is to make sensory stimuli conscious, cf. the perception theory . In order to become aware of a sensitive sensation, a combined performance of the primary and secondary sensory cortex fields is required.

A focus in the somatic-sensitive association area of areas 5 and 7 according to Brodmann results in tactile agnosia . Those affected can no longer recognize an object placed in their hand.

The precuneus and thus the superior parietal lobule play a role within the resting state network .

Individual evidence

  1. ↑ a b c d e Fritz Broser: Topical and clinical diagnosis of neurological diseases. 2nd Edition. U&S, Munich 1981, ISBN 3-541-06572-9 , chap. 2-20, p. 140
  2. ↑ a b Peter Duus: Neurological-topical diagnostics. Anatomy, physiology, clinic . 5th edition. Georg Thieme, Stuttgart 1990, ISBN 3-13-535805-4 , p. 387 ff.
  3. ↑ Peter Fransson, Guillaume Marrelec: The precuneus / posterior cingulate cortex plays a pivotal role in the default mode network. Evidence from a partial correlation network analysis . In: NeuroImage , Elsevier, Volume 42, Issue 3, September 2008, pp. 1178-1184, sciencedirect.com