NCT07777419

Brief Summary

With this study, the investigators want to investigate how deep brain stimulation (DBS) affects various cognitive and psychiatric symptoms of Parkinson's disease (PD). In particular, they will examine whether stimulation of the left hemisphere has a different effect than stimulation of the right hemisphere on cognitive and psychiatric symptoms.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
20

participants targeted

Target at below P25 for not_applicable

Timeline
27mo left

Started Aug 2026

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Progress7%
Aug 2026Dec 2028

Study Start

First participant enrolled

August 1, 2026

Completed
12 days until next milestone

First Submitted

Initial submission to the registry

August 13, 2026

Completed
7 days until next milestone

First Posted

Study publicly available on registry

August 20, 2026

Completed
1.9 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

July 31, 2028

Expected
5 months until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2028

Last Updated

September 4, 2026

Status Verified

August 1, 2026

Enrollment Period

2 years

First QC Date

August 13, 2026

Last Update Submit

September 1, 2026

Conditions

Parkinsons Disease (PD)

Keywords

Deep Brain StimulationNeuropsychiatric symptomsCognition

Outcome Measures

Primary Outcomes (1)

  • Fluency

    Change in composite verbal fluency score for left versus right hemispheric stimulation. To calculate the composite verbal fluency score, the standardized z-scores for phonemic and semantic verbal fluency task will be averaged. For the semantic fluency task, participants generate orally as many category names as possible during 2 minutes (German category 1: professions, category 2: hobbies; French category 1: furniture; category 2: fruit). During the phonemic fluency task, participants generate orally as many words as possible beginning with a certain letter while respecting the following rules: no repetition and no word with the same root, and no proper nouns (German: P-words, M-words; French: R-words, V-words). During each condition (right side stimulation OFF and left side stimulation OFF), one semantic fluency task and one phonemic fluency task will be performed (making sure the same letter and cateogry are only assessed once).

    Baseline visit

Secondary Outcomes (2)

  • Impulsivity

    Baseline visit

  • Neuropsychiatric

    Baseline visit

Study Arms (2)

Experimental Part II, right hemisphere first turned off

EXPERIMENTAL

Parkinson's disease patients of Part II, in whom the right hemisphere is first turned off

Other: DBS OFF state for left hemisphereOther: DBS OFF state for right hemisphere

Experimental Part II, left hemisphere first turned off

EXPERIMENTAL

Parkinson's disease patients of Part II, in whom the left hemisphere is first turned off

Other: DBS OFF state for left hemisphereOther: DBS OFF state for right hemisphere

Interventions

DBS OFF state for left hemisphereOTHER

DBS is turned off for the left hemisphere during the experiment

Experimental Part II, left hemisphere first turned offExperimental Part II, right hemisphere first turned off
DBS OFF state for right hemisphereOTHER

DBS is turned off for the right hemisphere during the experiment

Experimental Part II, left hemisphere first turned offExperimental Part II, right hemisphere first turned off

Eligibility Criteria

Age18 Years - 75 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Diagnosed with Parkinson's disease
  • Treated with subthalamic nucleus deep brain stimulation (STN-DBS)
  • For part I: General research consent for the analysis of routine clinical data
  • For part II of the study: ability to provide informed consent
  • native German or French speaker
  • Montreal Cognitive Assessment with score ≥ 20

You may not qualify if:

  • Atypical Parkinsonism
  • Other disease affecting the brain (e.g. Alzheimer's disease, vascular dementia, multiple sclerosis, stroke, traumatic brain injury, non-provoked epilepsy, brain tumour, etc.)
  • Haemorrhage during implantation of STN-DBS, which resulted in permanent cognitive or physical impairment
  • Schizophrenia, ongoing substance abuse, bipolar disorder or autism
  • For part II: Severe depressive disorder and/or suicidality
  • Insufficient quality or lack of brain imaging data pre and/or post STN-DBS

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University Hospital Inselspital, Berne

Bern, 3010, Switzerland

RECRUITING

MeSH Terms

Conditions

Parkinson Disease

Condition Hierarchy (Ancestors)

Parkinsonian DisordersBasal Ganglia DiseasesBrain DiseasesCentral Nervous System DiseasesNervous System DiseasesMovement DisordersSynucleinopathiesNeurodegenerative Diseases

Central Study Contacts

Deborah Amstutz, PhD

CONTACT

+41 31 66 4 05 67deborah.amstutz@insel.ch

Mario Sousa, MD

CONTACT

+41 31 63 2 86 52mario.sousa@insel.ch

Study Design

Study Type
interventional
Phase
not applicable
Allocation
RANDOMIZED
Masking
DOUBLE
Who Masked
PARTICIPANT, INVESTIGATOR
Purpose
OTHER
Intervention Model
CROSSOVER
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

August 13, 2026

First Posted

August 20, 2026

Study Start

August 1, 2026

Primary Completion (Estimated)

July 31, 2028

Study Completion (Estimated)

December 31, 2028

Last Updated

September 4, 2026

Record last verified: 2026-08

Data Sharing

IPD Sharing
Will not share

Locations

CH(1)