tVNS Effects on Motivation in Depression

Sponsor

University Hospital Tuebingen (Other)

Overall Status

Completed

CT.gov ID

NCT05120336

Collaborator

Universität Tübingen (Other)

Enrollment

Location

Arms

13.6

Actual Duration (Months)

4.9

Patients Per Site Per Month

Study Details

Study Description

Brief Summary

Attaining goals or rewards commonly entails response costs. In light of cost and benefits, how do participants decide what effort should be put in to give it a shot? Figuratively, you may "go with your gut", but the literal contribution of the gut-brain axis in allocating effort is poorly understood to date. Here, the investigators propose to investigate non-invasive transcutaneous vagal nerve stimulation (tVNS) as a potential modulator of energy metabolism and response vigor. Since the neural mechanisms causing the diverse cognitive and behavioral effects of the stimulation remain largely elusive, the investigators will use computational modeling of instrumental behavior and determine the primary metabolic effects of the stimulation. The investigators hypothesize that tVNS will lead to activation of afferent targets in the brain. In turn, the elicited brain activation is expected to mediate the cognitive effects of the stimulation. This may affect both sides of the utility equation because anti-depressive effects may correspond to boosting the benefit of effort whereas anti-nociceptive effects may reduce perceived costs of effort. Collectively, dissecting the cognitive effects of non-invasive tVNS in healthy individuals may facilitate the more widespread use as a treatment in mental disorders that are characterized by metabolic alterations such as depression.

Condition or Disease	Intervention/Treatment	Phase
Major Depressive Disorder	Device: transcutaneous vagus nerve stimulation Device: sham stimulation	N/A

Study Design

Study Type:

Interventional

Actual Enrollment :

67 participants

Allocation:

Randomized

Intervention Model:

Crossover Assignment

Masking:

Single (Participant)

Primary Purpose:

Basic Science

Official Title:

The Effects of Transcutaneous Vagus Nerve Stimulation on Motivation in Major Depressive Disorder

Actual Study Start Date :

Dec 11, 2019

Actual Primary Completion Date :

Jan 29, 2021

Actual Study Completion Date :

Jan 29, 2021

Arms and Interventions

Arm	Intervention/Treatment
Experimental: Non-depressed control participants: sham first, active taVNS second Non-depressed control participants receive sham stimulation in the first session (biphasic stimulation with a frequenyc of 25 Hz, 30s OFF/30s ON at the earlobe (sham) for 1.5 h). In a second identical session, they receive active stimulation with the same parameters (at the cymba conchae).	Device: transcutaneous vagus nerve stimulation Non-invasive brain stimulation technique that is used to stimulate vagal afferent projections to the nucleus of the solitary tract. Invasive VNS has been approved for the treatment of treatment-resistant depression. Other Names: transcutaneous auricular vagus nerve stimulation Device: sham stimulation Sham procedure for active transcutaneous vagus nerve stimulation Other Names: transcutaneous stimulation of the earlobe
Experimental: Patients with major depressive disorders: sham first, active taVNS second participants with depression receive sham stimulation in the first session (biphasic stimulation with a frequenyc of 25 Hz, 30s OFF/30s ON at the earlobe (sham) for 1.5 h). In a second identical session, they receive active stimulation with the same parameters (at the cymba conchae).	Device: transcutaneous vagus nerve stimulation Non-invasive brain stimulation technique that is used to stimulate vagal afferent projections to the nucleus of the solitary tract. Invasive VNS has been approved for the treatment of treatment-resistant depression. Other Names: transcutaneous auricular vagus nerve stimulation Device: sham stimulation Sham procedure for active transcutaneous vagus nerve stimulation Other Names: transcutaneous stimulation of the earlobe
Experimental: Patients with major depressive disorders: active taVNS first, sham second participants with depression receive active stimulation in the first session (biphasic stimulation with a frequenyc of 25 Hz, 30s OFF/30s ON at the cymba conchae (active) for 1.5 h). In a second identical session, they receive sham stimulation with the same parameters (at the earlobe).	Device: transcutaneous vagus nerve stimulation Non-invasive brain stimulation technique that is used to stimulate vagal afferent projections to the nucleus of the solitary tract. Invasive VNS has been approved for the treatment of treatment-resistant depression. Other Names: transcutaneous auricular vagus nerve stimulation Device: sham stimulation Sham procedure for active transcutaneous vagus nerve stimulation Other Names: transcutaneous stimulation of the earlobe
Experimental: Non-depressed control participants: active taVNS first, sham second Non-depressed control participants receive active stimulation in the first session (biphasic stimulation with a frequenyc of 25 Hz, 30s OFF/30s ON at the cymba conchae (active) for 1.5 h). In a second identical session, they receive sham stimulation with the same parameters (at the earlobe).	Device: transcutaneous vagus nerve stimulation Non-invasive brain stimulation technique that is used to stimulate vagal afferent projections to the nucleus of the solitary tract. Invasive VNS has been approved for the treatment of treatment-resistant depression. Other Names: transcutaneous auricular vagus nerve stimulation Device: sham stimulation Sham procedure for active transcutaneous vagus nerve stimulation Other Names: transcutaneous stimulation of the earlobe

Outcome Measures

Primary Outcome Measures

Food reward ratings [during stimulation (compared to sham)]
Operationalized via visual analogue scale ratings of liking [-100 - 100] and wanting [0-100] in a food cue reactivity task
Motivation to work for rewards: frequency of button presses to gain food an monetary rewards [during stimulation (compared to sham)]
Operationalized via the relative frequency of button presses on an Xbox controller in an effort allocation task during either the first seconds of each trial (invigoration) or each complete trial (maintenance)
Reward learning: correct choices [during stimulation (compared to sham)]
Operationalized via number of correct value-based choices in a valenced go/no-go learning task
Positive and negative mood [Pre stimulation and 20 minutes post stimulation (compared to sham)]
Operationalized via visual analogue ratings (0-100) of positive and negative affect schedule mood items