Theta Oscillations at Subthalamic Region Predicts Hypomania State After Deep Brain Stimulation in Parkinson's Disease

Yi-Chieh Chen; Hau-Tieng Wu; Po-Hsun Tu; Chih-Hua Yeh; Tzu-Chi Liu; Mun-Chun Yeap; Yi-Ping Chao; Po-Lin Chen; Chin-Song Lu; Chiung-Chu Chen

doi:10.3389/fnhum.2021.797314

Theta Oscillations at Subthalamic Region Predicts Hypomania State After Deep Brain Stimulation in Parkinson's Disease

Front Hum Neurosci. 2021 Dec 20:15:797314. doi: 10.3389/fnhum.2021.797314. eCollection 2021.

Authors

Yi-Chieh Chen^{1

2

3}, Hau-Tieng Wu^{4

5}, Po-Hsun Tu^{3

6}, Chih-Hua Yeh^{3

7}, Tzu-Chi Liu², Mun-Chun Yeap⁶, Yi-Ping Chao⁸, Po-Lin Chen¹, Chin-Song Lu⁹, Chiung-Chu Chen^{1

2

3}

Affiliations

¹ Division of Movement Disorders, Department of Neurology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
² Neuroscience Research Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
³ College of Medicine, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
⁴ Department of Mathematics, Duke University, Durham, NC, United States.
⁵ Department of Statistical Science, Duke University, Durham, NC, United States.
⁶ Department of Neurosurgery, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
⁷ Department of Neuroradiology, Chang Gung Memorial Hospital, Taoyuan, Taiwan.
⁸ Graduate Institute of Biomedical Engineering, Chang Gung University, Taoyuan, Taiwan.
⁹ Professor Lu Neurological Clinic, Taoyuan, Taiwan.

Abstract

Subthalamic nucleus (STN) deep brain stimulation (DBS) is an effective treatment for the motor impairments of patients with advanced Parkinson's disease. However, mood or behavioral changes, such as mania, hypomania, and impulsive disorders, can occur postoperatively. It has been suggested that these symptoms are associated with the stimulation of the limbic subregion of the STN. Electrophysiological studies demonstrate that the low-frequency activities in ventral STN are modulated during emotional processing. In this study, we report 22 patients with Parkinson's disease who underwent STN DBS for treatment of motor impairment and presented stimulation-induced mood elevation during initial postoperative programming. The contact at which a euphoric state was elicited by stimulation was termed as the hypomania-inducing contact (HIC) and was further correlated with intraoperative local field potential recorded during the descending of DBS electrodes. The power of four frequency bands, namely, θ (4-7 Hz), α (7-10 Hz), β (13-35 Hz), and γ (40-60 Hz), were determined by a non-linear variation of the spectrogram using the concentration of frequency of time (conceFT). The depth of maximum θ power is located approximately 2 mm below HIC on average and has significant correlation with the location of contacts (r = 0.676, p < 0.001), even after partializing the effect of α and β, respectively (r = 0.474, p = 0.022; r = 0.461, p = 0.027). The occurrence of HIC was not associated with patient-specific characteristics such as age, gender, disease duration, motor or non-motor symptoms before the operation, or improvement after stimulation. Taken together, these data suggest that the location of maximum θ power is associated with the stimulation-induced hypomania and the prediction of θ power is frequency specific. Our results provide further information to refine targeting intraoperatively and select stimulation contacts in programming.

Keywords: Parkinson's disease; hypomania; local field potentials (LFP); subthalamic deep brain stimulation; theta oscillation.