Why acute unilateral vestibular cortex lesions mostly manifest without vertigo

Area of Science:

• Neuroscience
• Neurology
• Vestibular System

Background:

• Acute strokes involving the middle cerebral artery (MCA) can rarely cause transient vertigo.
• Understanding the specific brain regions responsible for vertigo in MCA strokes is crucial.

Purpose of the Study:

• To identify critical vestibular areas in the temporoparietal cortex responsible for vertigo in MCA strokes.
• To elucidate the mechanism by which vertigo is suppressed in most unilateral lesions of these areas.

Main Methods:

• Analysis of 10 published cases of MCA stroke with vertigo.
• Overlapping CT/MRI lesion data to pinpoint affected vestibular network areas.

Main Results:

• Lesions in the posterior retroinsular cortex (parieto-insular vestibular cortex) were identified in 8 cases.
• Lesions in the parietal vestibular cortex were observed in 2 cases.

Conclusions:

• Vestibular cortical vertigo in MCA strokes is primarily linked to lesions in the retroinsular vestibular network.
• The unaffected contralateral hemisphere may suppress vertigo via visual-vestibular integration for motion perception.