NeuroNationMED

The study lasts a total of approximately 12 weeks and is divided into several steps:

1. Contact & screening

After you contact us, you will undergo a telephone screening (lasting approximately 20–30 minutes) and an online screening (lasting approximately 60–90 minutes).

2. On-site examinations

Two neuropsychological tests will be conducted at our clinic (each lasting approximately 90 minutes): one at the beginning and one at the end of the study.

In addition, you will complete two online questionnaires:

• one week before each on-site appointment
• once before the start and once at the end of the study

Each questionnaire takes approximately 60 minutes to complete

3. Training phase

During the 12-week intervention phase, participants will be randomly assigned to one of three study groups:

The experimental group will conduct cognitive training independently at home using the NeuroNation MED app (3 times per week, approx. 30 minutes each) and will also receive weekly psychoeducational content via email.

The active control group receives weekly psychoeducational content via email.

The control group (treatment as usual, TAU) serves as a comparison group, receives no additional training intervention, and is cared for according to the usual treatment.

All three groups are equally important for the scientific findings of the study.

You can participate if you:

• are at least 18 years old
• have sufficient German language skills
• can operate a smartphone (with or without visual aids)
• have a clinically confirmed diagnosis of a depressive episode (ICD-10: F32) or a recurrent depressive episode (ICD-10: F33) without psychotic symptoms

Unfortunately, participation is not possible if you have:

• current or previous psychotic disorders
• acute suicidal tendencies or a severe mental health crisis
• certain neurological disorders (e.g., epilepsy, multiple sclerosis, Parkinson's disease, stroke)
• serious infections
• are currently taking benzodiazepines
• are currently using illegal substances (including cannabis)

The exact assessment will be made during the telephone screening.

By participating, you will be making an important contribution to the further development of scientifically based treatments for depression.

In addition, after completing your participation in the study, you will receive free access to the NeuroNation MED app for a period of 12 months.

Study registration (DRKS): DRKS00036429