Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, ON, M5T 2S8, Canada; Division of Neurosurgery, Department of Surgery, Toronto Western Hospital, University of Toronto, 399 Bathurst Street, Toronto, ON, M5T 2S8, Canada; Department of Neurological Surgery, University of Southern California, 1200 North State Street, Suite 3300, Los Angeles, CA, 90033, USA; USC Neurorestoration Center, Keck School of Medicine of USC, 1333 San Pablo Street, McKibben Hall B51, Los Angeles, CA, 90033, USA.
Krembil Research Institute, University Health Network, 60 Leonard Avenue, Toronto, ON, M5T 2S8, Canada.
Brain Stimul. 2021 Jul-Aug;14(4):754-760. doi: 10.1016/j.brs.2021.04.016. Epub 2021 Apr 30.
Parkinson's disease (PD) is a common neurodegenerative disorder that results in movement-related dysfunction and has variable cognitive impairment. Deep brain stimulation (DBS) of the dorsal subthalamic nucleus (STN) has been shown to be effective in improving motor symptoms; however, cognitive impairment is often unchanged, and in some cases, worsened particularly on tasks of verbal fluency. Traditional DBS strategies use high frequency gamma stimulation for motor symptoms (∼130 Hz), but there is evidence that low frequency theta oscillations (5-12 Hz) are important in cognition.
We tested the effects of stimulation frequency and location on verbal fluency among patients who underwent STN DBS implantation with externalized leads. During baseline cognitive testing, STN field potentials were recorded and the individual patients' peak theta frequency power was identified during each cognitive task. Patients repeated cognitive testing at five different stimulation settings: no stimulation, dorsal contact gamma (130 Hz), ventral contact gamma, dorsal theta (peak baseline theta) and ventral theta (peak baseline theta) frequency stimulation.
Acute left dorsal peak theta frequency STN stimulation improves overall verbal fluency compared to no stimulation and to either dorsal or ventral gamma stimulation. Stratifying by type of verbal fluency probes, verbal fluency in episodic categories was improved with dorsal theta stimulation compared to all other conditions, while there were no differences between stimulation conditions in non-episodic probe conditions.
Here, we provide evidence that dorsal STN theta stimulation may improve verbal fluency, suggesting a potential possibility of integrating theta stimulation into current DBS paradigms to improve cognitive outcomes.
帕金森病（PD）是一种常见的神经退行性疾病，导致与运动相关的功能障碍，并伴有不同程度的认知障碍。背侧丘脑底核（STN）的深部脑刺激（DBS）已被证明可有效改善运动症状；然而，认知障碍通常没有改善，在某些情况下甚至恶化，尤其是在词语流畅性任务上。传统的 DBS 策略使用高频伽马刺激来治疗运动症状（∼130 Hz），但有证据表明低频θ振荡（5-12 Hz）在认知中很重要。
我们测试了刺激频率和位置对接受 STN-DBS 植入术的患者词语流畅性的影响，这些患者使用外部化导联。在基线认知测试期间，记录 STN 场电位，并在每个认知任务中确定个体患者的峰值θ频率功率。患者在五种不同的刺激设置下重复认知测试：无刺激、背侧接触γ（130 Hz）、腹侧接触γ、背侧θ（峰值基线θ）和腹侧θ（峰值基线θ）频率刺激。
与无刺激相比，与背侧或腹侧γ刺激相比，急性左背侧峰值θ频率 STN 刺激可整体改善词语流畅性。根据词语流畅性探针的类型进行分层，与所有其他条件相比，背侧θ刺激可改善情景类别词语流畅性，而在非情景探针条件下，刺激条件之间没有差异。
在这里，我们提供了证据表明背侧 STNθ刺激可能改善词语流畅性，这表明将θ刺激整合到当前 DBS 范式中以改善认知结果的可能性。
