So far, antidepressant drugs have limited memory improvement. Transcranial direct current stimulation, as a non-invasive and safe neuroregulatory technique, is a new direction to improve memory.In this study, transcranial direct current stimulation of the greater occipital nerve was used to explore the effect of improving memory function in patients with stable depression, and related studies were conducted on the locus coeruleus-noadrenal loop and the functional connection between locus coeruleus, hippocampus and amygdala.

In this study, a randomized, controlled, double-blind design was adopted. Patients with depression were randomly divided into an intervention group and a control group to receive true or fake tDCS stimulation respectively. Clinical data, memory and other related cognitive function assessment, EEG, resting state fMRI, saliva and blood indicators were collected two weeks before and two weeks after the intervention, and followed up for eight weeks. Finally, data correlation analysis was performed.

Inclusion Criteria:

1. Eligible for ICD-10 depressive episode (F32) or recurrent depressive disorder (F33) diagnosis;
2. Antidepressant therapy for at least 8 weeks, with no antidepressant adjustment for nearly 2 months
3. HAMD-17 scores ≤ 7 points at the time of enrollment; CGI score ≦2;
4. Chief complaint of memory impairment, PDQ-D score of cognitive impairment ≧17 points;
5. Right-handed.

Exclusion Criteria:

1. A history of major physical diseases;
2. Have other mental disorders that meet the diagnostic criteria of ICD-10;
3. Hearing, color blindness, color weakness or receive electroconvulsive therapy;
4. Alcohol dependence or substance abuse;
5. Patients with intellectual disability;
6. Pregnant or lactating women or those planning to become pregnant;
7. Patients with contraindications to tDCS.