---
title: Reduce tremor while preserving speech
nct_id: NCT04650932
phase: NA
status: RECRUITING
sponsor: University of California, Davis
study_type: INTERVENTIONAL
canonical_url: "https://parkinsonspathways.com/trial/NCT04650932"
clinicaltrials_gov: "https://clinicaltrials.gov/study/NCT04650932"
last_fetched: "2026-05-10T14:08:00.129Z"
source: "Parkinson's Pathways (curated)"
---
# Reduce tremor while preserving speech

**Goal (in five words):** Reduce tremor while preserving speech

**Official Title:** Dual Frequency, Dual Region Deep Brain Stimulation of the Subthalamic Nucleus in Parkinson's Disease

**Trial ID:** [NCT04650932](https://clinicaltrials.gov/study/NCT04650932)

## Key Facts

- **Phase:** NA
- **Status:** RECRUITING
- **Study Type:** INTERVENTIONAL
- **Sponsor:** University of California, Davis
- **Target Enrollment:** 10 participants
- **Start Date:** 2022-10-22
- **Completion Date:** 2026-06-30
- **Conditions:** Parkinson Disease
- **Interventions:** Deep brain stimulation
- **Intervention Types:** DEVICE

## Summary For Families

The goal is to test whether giving different electrical frequencies to the upper and lower parts of the subthalamic nucleus can better control tremor, slowness, and stiffness while reducing cognitive or speech side effects. The approach uses the already-implanted Boston Scientific Vercise DBS system to send targeted pulses to dorsal and ventral STN contacts, changing abnormal brain circuit activity that causes motor symptoms; it does not replace levodopa but can change how well motor control responds and may allow medication adjustments. Looking for adults 18 and older with idiopathic, advanced Parkinson's who already have the Vercise system implanted for at least 3 months with bilateral dorsal STN leads reaching the ventral STN, who can do cognitive testing in English and meet simple MoCA and depression score cutoffs.

## Eligibility

- **Minimum age:** 18 Years
- **Sex:** ALL

### Full Criteria

```
Inclusion Criteria:

* Individuals who are 18 years and older
* Individuals with idiopathic Parkinson's Disease who previously underwent implantation with the Boston Scientific VerciseTM DBS system
* Individuals who have been implanted with the Boston Scientific VerciseTM DBS system for at least 3 months
* Individuals diagnosed with advanced PD who had bilateral dorsal subthalamic nucleus DBS surgery, as standard of care for motor improvement, with distal contacts of the electrodes implanted into the ventral STN

Exclusion Criteria:

* Individuals unable to provide consent and/or lack capacity to consent
* Individuals diagnosed with any cognitive or physical impairments that would limit their ability to participate in the cognitive testing
* Individuals who score below 15 on the Montreal Cognitive Assessment Test-Blind
* Individuals who score above 20 on the Center for Epidemiologic Studies Depression Scale
* Pregnant women (note: pregnant women are not candidates for DBS surgery), and prisoners
* Non-English speaking individuals. Cognitive tasks will only be conducted in English.
```

## Locations (1)

- UC Davis Health, Sacramento, California, United States _(38.5816, -121.4944)_
  - Jessica Beatty, MS — (CONTACT) — 916-734-0901 — jabeatty@ucdavis.edu
  - Janice Wang-Polagruto, PhD, CCRP — (CONTACT) — 916-551-3244 — jfwang@ucdavis.edu

## Central Contacts

- Kiarash Shahlaie, MD, PhD — (CONTACT) — 916-703-5505 — krshahlaie@ucdavis.edu
- Janice Wang-Polagruto, PhD, CCRP — (CONTACT) — 916-551-3244 — jfwang@ucdavis.edu

---

*Canonical: https://parkinsonspathways.com/trial/NCT04650932*  
*HTML version: https://parkinsonspathways.com/trial/NCT04650932*  
*Source data: https://clinicaltrials.gov/study/NCT04650932*