Adding mindfulness, music, and a light-occluding eye mask during ketamine infusion for depression did not improve antidepressant effects compared to ketamine alone, but it enriched the subjective experience. Participants in the combined sensory intervention group reported deeper engagement, a stronger sense of connection to reality, increased focus, moments of relief from sadness, and feelings of awe and spiritual insight. However, four individuals in that group reported discomfort. The findings suggest that while the sensory interventions make the experience more meaningful for many, they may cause discomfort for a few, and making them optional could avoid this.
A single intravenous dose of ketamine (0.5 mg/kg over 40 minutes) rapidly reduces attentional bias toward sad stimuli in adults with moderate-to-severe depression. A novel dual-probe video task measuring attentional bias showed good test-retest reliability at one week and one month before treatment. In two studies totaling 83 participants, attentional bias decreased from before to 24 hours after ketamine infusion. In the first study, attentional bias correlated with clinician-rated depressive symptoms at each pretreatment assessment. In the second study, reductions in attentional bias correlated with symptom improvement. The findings suggest that reducing attentional bias may be a cognitive mechanism underlying ketamine's rapid antidepressant effects.