tVNS Effects on Motivation in Depression

University Hospital Tuebingen

Status: Completed

Conditions: Major Depressive Disorder

Treatments: Device: sham stimulation; Device: transcutaneous vagus nerve stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT05120336

NBK_TUE004

Details and patient eligibility

About

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.

Enrollment: 67 patients

Sex: All

Ages: 18 to 65 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 30 kg/m^2 > BMI > 18.5 kg/m^2

Exclusion criteria

lifetime

• brain injury

• coronary heart disease and occurred apoplexy

• schizophrenia

• bipolar disorder

• implants (e.g., cochlea implant)

• asthma

  12 month

• severe substance use disorders (DSM-V), except tobacco

• obessive compulsive disorder

• somatic symptom disorder

• eating disorder

Trial design

Primary purpose: Basic Science

Allocation: Randomized

Interventional model: Crossover Assignment

Masking: Single Blind

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67 participants in 4 patient groups

Non-depressed control participants: sham first, active taVNS second

Experimental group

Description:

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).

Treatment:

Device: transcutaneous vagus nerve stimulation

Device: sham stimulation

Patients with major depressive disorders: sham first, active taVNS second

Experimental group

Description:

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).

Treatment:

Device: transcutaneous vagus nerve stimulation

Device: sham stimulation

Patients with major depressive disorders: active taVNS first, sham second

Experimental group

Description:

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).

Treatment:

Device: transcutaneous vagus nerve stimulation

Device: sham stimulation

Non-depressed control participants: active taVNS first, sham second

Experimental group

Description:

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).

Treatment:

Device: transcutaneous vagus nerve stimulation

Device: sham stimulation