Berrin Çavuşoğlu1, Duygu Hünerli-Gündüz2, İlayda Kıyı2, Raif Çakmur3, Görsev G. Yener4, Emel Ada5

1Dokuz Eylul University Institute of Health Sciences, Department of Medical Physics, Izmir, Türkiye
2Dokuz Eylul University Institute of Health Sciences, Department of Neuroscience, Izmir, Türkiye
3Dokuz Eylül University Faculty of Medicine, Department of Neurology, Izmir, Türkiye
4Izmir University of Economics, Faculty of Medicine, Izmir, Türkiye, Izmir International Biomedicine and Genome Institute, Izmir, Türkiye, Dokuz Eylül University, Brain Dynamics Multidisciplinary Research Center, Izmir, Türkiye
5Dokuz Eylül University Faculty of Medicine, Department of Radiology, Izmir, Türkiye

Keywords: Mild cognitive impairment, Parkinson’s disease, magnetic resonance imaging, cortical thickness, neurocognitive functions

Abstract

Objective: This study investigated cortical thickness differences and their relationships with cognitive functions in Parkinson’s disease (PD) with mild cognitive impairment (MCI) and cognitively normal (CN).

Materials and Methods: Twenty-two patients with PD-MCI, 23 with PD-CN, and 23 healthy controls with structural brain magnetic resonance imaging scans and complete neuropsychological tests were enrolled in this study. Cortical thickness analysis was performed using the Statistical Parametric Mapping 12 software package. Correlations with cognitive functions were examined.

Results: Cortical thickness was significantly lower in the PD-CN and PD-MCI patient groups than in healthy controls in the left precuneus and isthmuscingulate cortex, right pars orbitalis, insula, and lateral orbitofrontal cortex. In addition, the PD-MCI group also exhibited cortical thinning in the left superior temporal gyrus, transverse temporal cortex, supramarginal gyrus, and bilateral posterior cingulate cortex compared with healthy controls. Correlation analyses among cortical thickness and cognitive scores of PD also revealed moderate associations between memory and the posterior cingulate cortex; language and the precuneus; and executive functions and the insula and isthmus-posterior cingulate cortices.

Conclusion: MCI in PD may be related to cortical alterations in the posterior cingulate cortex and the left temporoparietal cortex, which has been associated with subtle cognitive deficits in PD.

Ethics Committee Approval

Ethics Committee approval for this study was received from the Non-Invasive Research Ethics Board of Dokuz Eylul University (decision no: 2015/07-42).

Peer Review

Externally and internally peer-reviewed.

Author Contributions

Concept: B.Ç., D.H., G.Y., E.A., Design: B.Ç., D.H., G.Y., E.A., Data Collection or Processing: B.Ç., D.H., İ.K., R.Ç., G.Y., E.A., Analysis or Interpretation: B.Ç., D.H., İ.K., Literature Search: B.Ç., D.H., G.Y., E.A., Writing: B.Ç., D.H., R.Ç., G.Y., E.A.

Conflict of Interest

No conflict of interest was declared by the authors.

Financial Disclosure

The inclusion of healthy elderly participants in this study was supported by Dokuz Eylül University Scientific Research Projects Coordination Unit (project number: 2018.KB.SAG.084).