Combining imaging and deep brain recordings in humans to understand the role of the brainstem in Parkinson’s disease 

 

In Parkinson’s disease (PD), degeneration in subcortical structures and changes in neuronal activity in the subthalamic nucleus (STN) are implicated in motor symptoms. The development of new imaging techniques provides the opportunity to explore the role of both for the first time. Particularly, deep drain stimulation (DBS) sensing technology allows for the measurement of local field potentials in the STN whilst the person with PD performs activities such as walking. In addition, measures of free water and magnetic susceptibility allow for the identification and assessment of neurodegeneration in small subcortical structures. 

 

We are currently investigating how degeneration in subcortical structures such as the substantia nigra (SN) and the pedunculopontine nucleus (PPN) is associated with Parkinson’s-related pathological brain activity measured through LFP in the STN. We have undertaken multimodal MRI pre DBS surgery to extract structural metrics that index degeneration in subcortical structures. Post-surgery, we are recording on and off medication walking, resting and standing (with motion tracking) with mobile EEG and LFP.  

 

Importantly, this work will help us understand how structures outside the basal ganglia, like the PPN, are influencing Parkinson’s symptoms, and how they could be targeted in new treatment strategies.