B. longum has been extensively researched for its neuroenteric properties including stimulation of pathways between the gut and brain via the vagus nerve; normalization of anxiety-like behavior and hippocampal brain-derived neurotrophic factor in mice with infectious colitis; and modulation of resting neural activity, reduction of mental fatigue, and improving activation of brain coping centers to counter-regulate negative emotions [82, 83]. Here, BDNF is linked to Anxiety.