This study evaluates the use of brain activity monitoring for early identification of pharmaceutical treatment efficacy and development of depression deterioration events.

The study will be conducted in two arms:

In arm I, participants diagnosed with depression. In arm II, healthy participants.

Arm I - Participants that need to start or switch their pharmacological antidepressant therapy will be recruited. Their clinical status will be evaluated and their EEG characteristics will be collected.

Arm II - Clinical and EEG characteristics of Healthy volunteers will collected on a similar timetable.

Inclusion Criteria:

• Participant is willing and able to give informed consent for participation in the study.
• Male or Female, aged 18 -70 years (Adult, Senior)
• Able and willing to comply with all study requirements.

Additional Inclusion Criteria for Arm I

• Diagnosed with depression
• Being within 2 days of receiving pharmaceutical treatment for depression for the first

time or changing dose or changing type of current pharmaceutical treatment or addition to

drug of current pharmaceutical treatment.

Additional Inclusion Criteria for Arm II

Brief Symptom Inventory (BSI < 2.3).

Exclusion Criteria:

The participant may not enter the study if ANY of the following apply:

• Diagnosed with Psychotic disorder.
• Diagnosed with Central Neurological disorder.
• A user of recreational or illicit drugs or has had a recent history of drug or alcohol abuse

or dependence.

• Hearing disorder and/or known ear drum impairment.
• High suicide risk as judged by the research team.