The Current Evidence Levels for Biofeedback and Neurofeedback Interventions in Treating Depression: A Narrative Review

Table 6

Summary of the studies in rt-fMRI neurofeedback.

Article

Sample

Demonstrates efficacy

Outcome measures

Statistical power

Control group

Multiple studies

Randomization

Superior to NT, PLA, or AT

Noninferior to TAU

Inclusion criteria

Treatment procedures

Data analysis

2+ independent studies

Superiority to PLA or AT

Required for level

1

2

2

3

3

4

4

4

4

4

4

5

Major depressive disorder (MDD)

Linden et al. [152] (positive↑)

Y

C, M

Y/N

Y

—

Y

Y

—

Y

Y

Y

—

Y

Takamura et al. [153] (L DLPFC↑)

Y

C, P1

Y/N

—

—

—

—

—

Y

Y

Y

—

—

Young et al., [147] (L amygdala↑)

Y

M

Y

Y

—

—

Y

—

Y

Y

Y

—

Y

Young et al. [150] (L amygdala↑)

Y

C, P1

Y

Y

—

Y

Y

—

Y

Y

Y

—

Y

Young et al. [148] (L amygdala↑)

Y

Cog

Y

Y

—

Y

Y

—

Y

Y

Y

—

Y

Zotev et al. [151] (L ACC, L amygdala↑, FαA, FβA)

Y

M

Y

Y

—

—

Y

—

Y

Y

Y

—

Y

Hamilton et al. [154] (salience network↓)

Y

Cog

Y

Y

—

—

Y

—

Y

Y

Y

—

Y

Depressive disorders other than MDD

Mehler et al. [36] (positive↑)

Y

C, P1

Y

Y

—

Y

Y/N

—

Y

Y

Y

—

—

Quevedo et al. [146] (amygdala+hippocampus↑)

Y

Cog

Y

—

—

—

—

—

Y

Y

Y

—

—

EG: sample size of the experimental group; CG: sample size of the control group; NT: no treatment; PLA: placebo intervention; AT: alternative treatment; TAU: treatment as usual; Y: yes (criterion fulfilled); Y/N: yes/no (criterion partly fulfilled); C: clinical outcome measure; P1: well-established subjective test of depression; M: test of mood; Cog: cognitive feature of depression; Positive: individual regions of interest active while positive vs. neutral stimuli observed; L: left; DLPFC: dorsolateral prefrontal cortex; ACC: anterior cingulate cortex; FαA, FβA: EEG frontal alpha/beta asymmetry; ↑: upregulation; ↓: downregulation.