Grey matter abnormalities in Tourette syndrome: an activation likelihood estimation meta-analysis

Area of Science:

• Neuroimaging
• Neurodevelopmental Disorders
• Grey Matter Abnormalities

Background:

• Tourette syndrome (TS) is a neurodevelopmental disorder characterized by motor and vocal tics.
• Previous neuroimaging studies show conflicting results regarding grey matter abnormalities in TS.
• This study performs an unbiased statistical meta-analysis of neuroimaging research on TS brain structures.

Purpose of the Study:

• To conduct a quantitative meta-analysis of neuroimaging studies to identify consistent grey matter abnormalities in Tourette syndrome.
• To investigate structural brain differences in patients with Tourette syndrome compared to healthy controls.

Main Methods:

• Utilized Activation Likelihood Estimation (ALE), a voxel-based quantitative meta-analysis technique.
• Included six neuroimaging studies comprising 247 TS patients and 236 healthy controls.
• Applied a statistical threshold of p < 0.05 (False Discovery Rate) and a cluster extent of 50 voxels.

Main Results:

• Significantly increased grey matter volumes observed in the bilateral thalamus, right hypothalamus, right precentral gyrus, left postcentral gyrus, left inferior parietal lobule, right lentiform nucleus, and left insula in TS patients.
• Significantly decreased grey matter volumes noted in the bilateral postcentral gyrus, bilateral anterior cingulate, bilateral insula, left posterior cingulate, and left postcentral gyrus in TS patients.
• Key findings include increased grey matter in the thalamus and lentiform nucleus, and decreased grey matter in the anterior cingulate gyrus.

Conclusions:

• The meta-analysis highlights significant grey matter volume alterations in the thalamus, lentiform nucleus, and anterior cingulate gyrus in Tourette syndrome patients.
• These affected regions are largely associated with cortico-striato-thalamo-cortical circuits.
• Larger sample size studies are recommended to validate these grey matter volume changes in Tourette syndrome.