Table 3. Effect of deep brain stimulation in patients with depressive disorder.

Reference(s)	Patients	Stimulation site	Effect
Schlaepfer et al., 2008 (20)	3	Nucleus accumbens	After only 1 week, 42% reduction in symptoms (as measured by HAM-D)
Malone et al., 2009 (19)	15	Ventral internal capsule and ventral striatum	Observation for 12 months: distinct reduction in symptoms by 57% in this period (as measured by HAM-D)
Mayberg et al., 2005 (22)	6	Subgenual area of cingulum	Observation for 6 months: 71% reduction in symptoms in 4 of 6 patients (as measured by HAM-D); remission in 2 patients (HAM-D ≤8)
Lozano et al., 2008 (21)	20	Subgenual area of cingulum	Observation for 12 months: distinct reduction in symptoms by an average 48% in this period, with 2 non-responders; remission in 7 patients (HAM-D ≤7)

HAM-D, Hamilton Rating Scale for Depression