Early and phasic cortical metabolic changes in vestibular neuritis onset

Area of Science:

• Neuroscience
• Vestibular System Research
• Medical Imaging

Background:

• Functional brain studies map vestibular processing areas and their network changes following vestibular lesions.
• Acute unilateral vestibular failure (UVF) induces dynamic cortical alterations, with different brain regions affected during symptom onset and recovery.

Purpose of the Study:

• To investigate the earliest changes in cortical metabolic activity in patients with vestibular neuritis (VN), a peripheral vestibular disorder.
• To identify specific brain regions involved in the initial response to acute vestibular imbalance.

Main Methods:

• Utilized [(18)F]fluorodeoxyglucose positron emission tomography (FDG-PET) to assess brain metabolism in eight VN patients.
• Compared metabolic activity during the first two days of VN symptoms with data from one month later and a healthy control group.

Main Results:

• Confirmed known sensorimotor network responses to vestibular deafferentation.
• Demonstrated, for the first time, the early involvement of the Entorhinal cortex (BAs 28, 34) and Temporal cortex (BA 38) in VN onset.
• Correlated metabolic changes with subjective reports of balance, anxiety, and depersonalization/derealization.

Conclusions:

• The Entorhinal cortex involvement may reflect spatial reorientation attempts, while Temporal cortex activity could relate to emotional responses to VN.
• These findings expand knowledge on the rapid and complex cortical adaptations to acute vestibular dysfunction.
• Highlights the dynamic nature of brain plasticity in response to peripheral vestibular lesions.