Revealing the Acute Effects of Dietary Components on Mood and Cognition: The Role of Autonomic Nervous System Responses

A growing body of literature suggests dietary components can support mood and cognitive function through the impact of their bioactive or sensorial properties on neural pathways. Of interest, objective measures of the autonomic nervous system-such as those regulating bodily functions related to heartbeat and sweating-can be used to assess the acute effects of dietary components on mood and cognitive function. Technological advancements in the development of portable and wearable devices have made it possible to collect autonomic responses in real-world settings, creating an opportunity to study how the intake of dietary components impacts mood and cognitive function at an individual level, day-to-day. In this paper, we aimed to review the use of autonomic nervous system responses such as heart rate or skin galvanic response to investigate the acute effects of dietary components on mood and cognitive performance in healthy adult populations. In addition to examining the existing methodologies, we also propose new state-of-the-art techniques that use autonomic nervous system responses to detect changes in proxy patterns for the automatic detection of stress, alertness, and cognitive performance. These methodologies have potential applications for home-based nutrition interventions and personalized nutrition, enabling individuals to recognize the specific dietary components that impact their mental and cognitive health and tailor their nutrition accordingly.

Dietary tryptophan-rich protein hydrolysate can acutely impact physiological and psychological measures of mood and stress in healthy adults

BACKGROUND

Tryptophan is the precursor to the mood regulating neurotransmitter serotonin. Its brain bioavailability from food can be dependent on the dietary source. Egg protein hydrolysate (EPH), a dietary supplement rich in tryptophan, has previously shown to acutely impact cognition, mood and stress benefits at 2 g dose. No data exist on the acute effects of lower doses in a food matrix.

METHODS

This exploratory study tested the acute effects of low-doses EPH (0.5, 1 g) in a food matrix on cognition, mood and stress. The study employed a double-blinded randomized controlled parallel design in 45 participants with three arms. The effects of the interventions were measured after a multi-task cognitive stressor on blood biomarkers, self-reported mood states, performances of attention, autonomic parameters and, emotional reactivity responses from electroencephalographic recording.

RESULTS

As compared to the reference, the 1 g EPH dose increased tryptophan bioavailability from baseline, and, both doses improved heart rate variability parameters related to parasympathetic activation while showing differences in the late neural response to negative versus neutral emotions. Post-hoc analyses indicated a gender difference in the baseline tryptophan bioavailability and further examination suggested the change in mood rating depends on the interaction between gender and change from baseline of tryptophan bioavailability.

CONCLUSIONS

Overall, this study suggests that low levels of tryptophan rich EPH in a food matrix positively impact mood or stress in acute settings and adds to the body of evidence linking tryptophan and dietary sources thereof with these benefits. Confirmatory randomized controlled trials are needed to confirm these findings.Trial registration number: CER-VD N°2019-00218.

Soothing Effect of an Edible Teether: A Pilot Study in Children during Primary Dentition Age

Background

Irritability and discomfort are common symptoms during teething periods in infants and toddlers. Non-pharmacological remedies to relieve teething symptoms include teethers and food for chewing. However, the efficacy of such remedies for their soothing effect has been poorly investigated.

Materials and methods

In this home-based pilot study, the soothing effect of a novel edible teether with a slowly dissolvable texture was investigated in 12 children aged 5 to 19 months old during primary dentition age. After parents observed their child getting irritable, the child received the edible teether for an exposure duration of 15 to 20 minutes. Parental ratings of children's mood states (crankiness, stress, happiness, and calmness) were collected using visual analog scales, and child cardiac measurements (heart rate and heart rate variability) were assessed using a wearable device. The soothing effect was quantified via mood ratings and physiological calming responses as a before-after comparison using Wilcoxon signed-rank tests.

Results

Parents perceived their child as significantly calmer and happier, less stressed, and marginally less cranky after edible teether exposure than before. The child cardiac variables showed no significant changes; however, exposure to the teether induced a marginal increase in HR within normal ranges, potentially indicating a stimulation effect.

Conclusion

The pilot study provides the first insight on the soothing effect of a novel edible teether on parent-reported mood states in young children during primary dentition age. Further research is needed to understand the relative contribution of the different components of an edible teether to the observed effects, such as texture and exposure duration, and to demonstrate its efficacy against a control product.

Trial registration

Swiss registry of clinical trial: CER-VD 2019-02155.

How to cite this article

Lerond C, Hudry J, Zahar S, et al. Soothing Effect of an Edible Teether: A Pilot Study in Children during Primary Dentition Age. Int J Clin Pediatr Dent 2021;14(4):525–530.

Exploring MEG brain fingerprints: Evaluation, pitfalls, and interpretations

Individual characterization of subjects based on their functional connectome (FC), termed "FC fingerprinting", has become a highly sought-after goal in contemporary neuroscience research. Recent functional magnetic resonance imaging (fMRI) studies have demonstrated unique characterization and accurate identification of individuals as an accomplished task. However, FC fingerprinting in magnetoencephalography (MEG) data is still widely unexplored. Here, we study resting-state MEG data from the Human Connectome Project to assess the MEG FC fingerprinting and its relationship with several factors including amplitude- and phase-coupling functional connectivity measures, spatial leakage correction, frequency bands, and behavioral significance. To this end, we first employ two identification scoring methods, differential identifiability and success rate, to provide quantitative fingerprint scores for each FC measurement. Secondly, we explore the edgewise and nodal MEG fingerprinting patterns across the different frequency bands (delta, theta, alpha, beta, and gamma). Finally, we investigate the cross-modality fingerprinting patterns obtained from MEG and fMRI recordings from the same subjects. We assess the behavioral significance of FC across connectivity measures and imaging modalities using partial least square correlation analyses. Our results suggest that fingerprinting performance is heavily dependent on the functional connectivity measure, frequency band, identification scoring method, and spatial leakage correction. We report higher MEG fingerprinting performances in phase-coupling methods, central frequency bands (alpha and beta), and in the visual, frontoparietal, dorsal-attention, and default-mode networks. Furthermore, cross-modality comparisons reveal a certain degree of spatial concordance in fingerprinting patterns between the MEG and fMRI data, especially in the visual system. Finally, the multivariate correlation analyses show that MEG connectomes have strong behavioral significance, which however depends on the considered connectivity measure and temporal scale. This comprehensive, albeit preliminary investigation of MEG connectome test-retest identifiability offers a first characterization of MEG fingerprinting in relation to different methodological and electrophysiological factors and contributes to the understanding of fingerprinting cross-modal relationships. We hope that this first investigation will contribute to setting the grounds for MEG connectome identification.