Consumption of Fermented Milk Product With Probiotic Modulates Brain Activity

Abstract

BACKGROUND & AIMS Changes in gut microbiota have been reported to alter signaling mechanisms, emotional behavior, and visceral nociceptive reflexes in rodents. However, alteration of the intestinal microbiota with antibiotics or probiotics has not been shown to produce these changes in humans. We investigated whether consumption of a fermented milk product with probiotic (FMPP) for 4 weeks by healthy women altered brain intrinsic connectivity or responses to emotional attention tasks. METHODS Healthy women with no gastrointestinal or psychiatric symptoms were randomly assigned to groups given FMPP (n = 12), a nonfermented milk product (n = 11, controls), or no intervention (n = 13) twice daily for 4 weeks. The FMPP contained Bifidobacterium animalis subsp Lactis, Streptococcus thermophiles, Lactobacillus bulgaricus, and Lactococcus lactis subsp Lactis. Participants underwent functional magnetic resonance imaging before and after the intervention to measure brain response to an emotional faces attention task and resting brain activity. Multivariate and region of interest analyses were performed. RESULTS FMPP intake was associated with reduced task-related response of a distributed functional network (49% cross-block covariance; P = .004) containing affective, viscerosensory, and somatosensory cortices. Alterations in intrinsic activity of resting brain indicated that ingestion of FMPP was associated with changes in midbrain connectivity, which could explain the observed differences in activity during the task. CONCLUSIONS Four-week intake of an FMPP by healthy women affected activity of brain regions that control central processing of emotion and sensation.

Probiotics drive gut microbiome triggering emotional brain signatures

“…Neural correlates of emotional decision-making and memory processes: Given that emotion and cognition are inseparable and probiotic administration can influence activity in brain areas associated with emotional processing, 6 we specifically analysed the effect of the probiotic on cognitive abilities associated with emotional processing, namely, decision-making and recognition memory. Probiotic recipients changed their decision about the selection of the most unpleasant stimuli less frequently than the control subjects (placebo and NI groups) during the ED task, reflecting an improvement in emotional attention.…”

“…Most of the evidence for an influence of gut microbiota on behavior is based on animal findings, with only a small number of studies 6-8 to support a similar relationship in humans. However, as the psychological assessment was based solely on self-reported measures, firm conclusions regarding the effects of probiotics on human behavior cannot be drawn from these findings.…”

“…Another study showed that probiotic intake for 4–6 weeks altered neural activity in brain regions that control central processing of emotion and sensation in healthy women but no change in gut microbial composition was detected. 6 …”

Gutsy Moves: The Amygdala as a Critical Node in Microbiota to Brain Signaling

“…[95] The main distinguishing feature was an alteration in the connectivity between an emotion regulation network (including the amygdala) and other brain regions involved in attention and sensory perception. In a separate study by the same group, [35] 4 weeks of a probiotic treatment was sufficient to alter functional network responses to emotional faces in healthy females. In particular, amygdala activity was dampened during the task and resting state connectivity of a network that included the Table 2.…”

“…Alterations in the volume, activity, and/ or connectivity of the amygdala (features influenced by the gut microbiota) [16,[35][36][37] have been reported in individuals diagnosed with schizophrenia, [38,39] attention deficit hyperactivity disorder (ADHD), [40] and autism spectrum disorders (ASD). [41,42] In particular, functional dysregulation of the amygdala is considered central to the social deficits observed in individuals with ASD.…”