Electroencephalography microstates highlight specific mindfulness traits.

The present study aimed to investigate the spontaneous dynamics of large-scale brain networks underlying mindfulness as a dispositional trait, through resting-state electroencephalography (EEG) microstates analysis. Eighteen participants had attended a standardized mindfulness-based stress reduction training (MBSR), and 18 matched waitlist individuals (CTRL) were recorded at rest while they were passively exposed to auditory stimuli. Participants' mindfulness traits were assessed with the Five Facet Mindfulness Questionnaire (FFMQ). To further explore the relationship between microstate dynamics at rest and mindfulness traits, participants were also asked to rate their experience according to five phenomenal dimensions. After training, MBSR participants showed a highly significant increase in FFMQ score, as well as higher observing and non-reactivity FFMQ sub-scores than CTRL participants. Microstate analysis revealed four classes of microstates (A-D) in global clustering across all subjects. The MBSR group showed lower duration, occurrence and coverage of microstate C than the control group. Moreover, these microstate C parameters were negatively correlated to non-reactivity sub-scores of FFMQ across participants, whereas the microstate A occurrence was negatively correlated to FFMQ total score. Further analysis of participants' self-reports suggested that MBSR participants showed a better sensory-affective integration of auditory interferences. In line with previous studies, our results suggest that temporal dynamics of microstate C underlie specifically the non-reactivity trait of mindfulness. These findings encourage further research into microstates in the evaluation and monitoring of the impact of mindfulness-based interventions on the mental health and well-being of individuals.

[Mirror neurons, neural substrate of action understanding?] / Neurones miroirs, substrat neuronal de la compréhension de l'action?

In 1992, the Laboratory of Human Physiology at the University of Parma (Italy) publish a study describing "mirror" neurons in the macaque that activate both when the monkey performs an action and when it observes an experimenter performing the same action. The research team behind this discovery postulates that the mirror neurons system is the neural basis of our ability to understand the actions of others, through the motor mapping of the observed action on the observer's motor repertory (direct-matching hypothesis). Nevertheless, this conception met serious criticism. These critics attempt to relativize their function by placing them within a network of neurocognitive and sensory interdependencies. In short, the essential characteristic of these neurons is to combine the processing of sensory information, especially visual, with that of motor information. Their elementary function would be to provide a motor simulation of the observed action, based on visual information from it. They can contribute, with other non-mirror areas, to the identification/prediction of the action goal and to the interpretation of the intention of the actor performing it. Studying the connectivity and high frequency synchronizations of the different brain areas involved in action observation would likely provide important information about the dynamic contribution of mirror neurons to "action understanding". The aim of this review is to provide an up-to-date analysis of the scientific evidence related to mirror neurons and their elementary functions, as well as to shed light on the contribution of these neurons to our ability to interpret and understand others' actions.

Psychometric properties of the Weight Locus of Control Scale (MWLCS): study with Spanish individuals of different anthropometric nutritional status.

INTRODUCTION: The Multidimensional Weight Locus of Control Scale (MWLCS) measures a person's beliefs regarding the locus of control or lack of locus of control over his/her body weight. PURPOSE: We aim to evaluate the factorial structure and psychometric properties of the MWLCS with Spanish normal weight, overweight and obese samples. METHODS: The research was carried out in two different studies. The first included a sample of 140 normal weight participants, selected out of a 274 sample recruited with an online survey. Study 2 was carried out in a sample of 633 participants recruited from the PREDIMED-Plus study. Out of them, 558 participants fulfilled the weight criteria and were categorized into: overweight (BMI 25 - < 29.99; N = 170), obese class I (BMI 30 - < 34.99; N = 266), and obese class II (BMI 35 - < 39.99; N = 122). Exploratory (EFA) and confirmatory (CFA) factor analyses were used to evaluate the factor structure of the MWLCS, and reliabilities and Spearman's correlations were estimated. Invariance measurement was tested across the three subgroups of weight in Study 2. RESULTS: A three-factor structure indicating weight locus of control factors (internal, chance, and powerful others) was supported, both via EFA in the normal weight sample and CFA in the overweight and obese samples. In the normal weight sample, the powerful others dimension was positively related to BMI and the dimensions of the Dutch Eating Behaviors Questionnaire. Additionally, the scale showed evidence of scalar invariance across the groups with different weight conditions. CONCLUSIONS: This scale seems to be a psychometrically appropriate instrument and its use is highly recommended when designing interventions for overweight or obese individuals. LEVEL OF EVIDENCE: Level V, descriptive study.

Modulation of the N30 generators of the somatosensory evoked potentials by the mirror neuron system.

The N30 component of the somatosensory evoked potential is known to be modulated by sensory interference, motor action, movement ideation and observation. We introduce a new paradigm in which the observation task of another person's hand movement triggers the somatosensory stimulus, inducing the N30 response in participants. In order to identify the possible contribution of the mirror neuron network (MNN) to this early sensorimotor processing, we analyzed the N30 topography, the event-related spectral perturbation and the inter-trial coherence on single electroencephalogram (EEG) trials, and we applied swLORETA to localize the N30 sources implicated in the time-frequency domain at rest and during observation, as well as the generators differentiating these two contextual brain states. We found that N30 amplitude increase correlated with increased contralateral precentral alpha, frontal beta, and contralateral frontal gamma power spectrum, and with central and precentral alpha and parietal beta phase-locking of ongoing EEG signals. We demonstrate specific activation of the contralateral post-central and parietal cortex where the angular gyrus (BA39), an important MNN node, is implicated in this enhancement during observation. We conclude that this part of the MNN, involved in proprioceptive processing and more complex body-action representations, is already active prior to somatosensory input and may enhance N30.

Validation of the Dutch Eating Behavior Questionnaire (DEBQ) in a sample of Spanish women.

The Dutch Eating Behavior Questionnaire (DEBQ) was developed to measure eating styles that may contribute to or attenuate the development of overweight. It comprises three scales that measure emotional, external and restrained eating. The main goal of this study is to evaluate the internal structure of the Spanish version of the DEBQ using updated psychometric techniques in a sample of women. A sample of 647 Spanish females answered the questionnaire. Both exploratory structural equation modeling and confirmatory factor analysis were used to evaluate the factor structure of the DEBQ. Reliabilities were estimated with Cronbach's alpha. The relations between the subscales of the DEBQ and age, BMI, and scores on the Eating Attitude Test-26 (EAT) and the Restrained Scale-Revised (RS) were computed with Pearson correlations. Results showed that the internal structure was similar to the theoretical proposal, although items associated with boredom and idleness presented cross-loading problems. The reliability estimates were satisfactory. The Emotional and External Eating factors correlated with the BMI, and External Eating was negatively correlated with age. The Restraint factor of the DEBQ showed significant relationships with scales of the EAT-26 and RS. The dimensional validity of the DEBQ is reproduced in a Spanish sample, and the DEBQ seems to be an effective instrument for research in Spanish females. Minor modifications to the DEBQ are recommended.

Efficacy and acceptability of an Internet platform to improve the learning of nutritional knowledge in children: the ETIOBE Mates.

Possessing sufficient nutritional knowledge is a necessary component in the prevention and treatment of obesity. A solid understanding of nutrition can help people make appropriate food selections and can also help correct irrational ideas or myths people may believe about food. It is a challenge to provide this information to children in ways that are exciting. Thus, we propose an online video game platform to deliver the information. The objective of this study was to study the efficacy and acceptability of an online game called 'ETIOBE Mates' that was designed to improve children's nutritional knowledge; furthermore, we compare it with the traditional paper-pencil mode of information delivery. A sample of 228 children participated in the study. Participants were divided into two groups: an experimental group (who used ETIOBE Mates) and a control group (who were given a pamphlet). Both groups increased their scores for nutritional knowledge. The interaction between group × time was also statistically significant; it indicated that acquisition of nutritional knowledge was superior in the experimental group. The children considered the serious games platform to be a useful medium for improving their nutritional knowledge. Online games can be an effective method of delivery for preventive and treatment tasks that are otherwise tedious for children.

Emotional eating and food intake after sadness and joy.

Do people with a high score on a scale for eating in response to negative emotions also show high food intake in response to positive emotions? We studied these effects in 60 female students that were preselected on the basis of extreme high or low scores on an emotional eating questionnaire. Using a between subject design we experimentally tested the difference in food intake following a mood induction designed to induce joy or sadness (the joy vs. sad mood condition). The high and low emotional eaters did not differ in their food intake, but emotional eating significantly moderated the relationship between mood condition and food intake. Whereas low emotional eaters ate similar amounts after the sad and after the joy mood condition, high emotional eaters ate significantly more after the sad mood condition than after the joy mood condition. A further finding was that a similar moderator effect for emotional eating was found for intake of sweet food but not for intake of salty food. These findings would suggest that eating in response to negative and to positive emotions refer to two different constructs.

Eating-related environmental factors in underweight eating disorders and obesity: are there common vulnerabilities during childhood and early adolescence?

OBJECTIVE: This study aimed to examine whether there is an association between individual, social and family influences and dysfunctional eating patterns early in life and the likelihood of developing a subsequent underweight eating disorder (ED) or obesity. METHOD: The total sample comprised 152 individuals (underweight ED, n = 45; obese patients, n = 65; healthy controls; n = 42) from Barcelona, Spain. The Cross-Cultural Questionnaire (CCQ) was used to assess early eating influences as well as individual and family eating patterns and attitudes towards food. RESULTS: Even though a few shared eating influences emerged for both groups, unique factors were also observed. Whereas relationship with friends, teasing about eating habits by family members and the mass media were of specific relevance to the underweight ED group, the patient's own physical appearance, body dissatisfaction, teasing about eating habits by friends, teasing about body shape by family members and dysfunctional eating patterns were unique to obesity. CONCLUSIONS: Overlapping environmental risk factors provide evidence for integral prevention and intervention approaches that simultaneously tackle a range of weight-related problems. The unique factors might be important for targeting high-risk individuals.

Brain potential responses involved in decision-making in weightlessness.

The brain is essential to human adaptation to any environment including space. We examined astronauts' brain function through their electrical EEG brain potential responses related to their decision of executing a docking task in the same virtual scenario in Weightlessness and on Earth before and after the space stay of 6 months duration. Astronauts exhibited a P300 component in which amplitude decreased during, and recovered after, their microgravity stay. This effect is discussed as a post-value-based decision-making closing mechanism; The P300 amplitude decrease in weightlessness is suggested as an emotional stimuli valence reweighting during which orbitofrontal BA10 would play a major role. Additionally, when differentiating the bad and the good docks on Earth and in Weightlessness and keeping in mind that astronauts were instantaneously informed through a visual cue of their good or bad performance, it was observed that the good dockings resulted in earlier voltage redistribution over the scalp (in the 150-250 ms period after the docking) than the bad dockings (in the 250-400 ms) in Weightlessness. These results suggest that in Weightlessness the knowledge of positive or negative valence events is processed differently than on Earth.

Frontal phasic and oscillatory generators of the N30 somatosensory evoked potential.

The N30 component of somatosensory evoked potentials has been recognized as a crucial index of brain sensorimotor processing and has been increasingly used clinically. Previously, we have shown that the N30 is accompanied by both an increase of the power spectrum of the ongoing beta-gamma EEG (event related synchronization, ERS) and by a reorganization (phase-locking) of the spontaneous phase of this rhythm (inter-trials coherency, ITC). In order to localize its sources taking into account both the phasic and oscillatory aspects of the phenomenon, we here apply swLORETA methods on averaged signals of the event-related potential (ERP) from a 128 scalp-electrodes array in time domain and also on raw EEG signals in frequency domain at the N30 peak latency. We demonstrate that the two different mechanisms that generate the N30 component power increase (ERS) and phase locking (ITC) across EEG trials are spatially localized in overlapping areas in the precentral cortex, namely the motor cortex (BA4) and the premotor cortex (BA6). From this common region, the generator of the N30 event-related potential expands toward the posterior part of BA4, the anterior part of BA6 and the prefrontal cortex (BA9). These latter areas also present significant ITC sources in the beta-gamma frequency range, but without significant power increase of this rhythm. This demonstrates that N30 results from network activity that depends on distinct oscillating and phasic generators localized in the frontal cortex.

PDA self-register system for eating disorders: a study on acceptability and satisfaction.

Self-monitoring techniques, such as the use of dietary registers, are considered to be central to cognitive-behavioral treatment of Eating Disorders (ED). This information allows the clinician to identify the triggers of the behaviors associated to ED as purges and/or binges, and the associated thoughts and emotions, helping to carry out a more accurate assessment. Traditionally these registers are made with paper and pencil mode, where the patient has to register every eating and the emotions/thoughts associated; but this system has some problems, as low portability, low adherence or methodological difficulties. The use of PDA for self-registers can help to solve these problems. The aim of this study is to study the levels of acceptability and satisfaction with PDAs self-register system specifically designed for assessment and treatment of ED. Samples of 30 subjects diagnosed with ED are receiving a PDA with software specifically designed for recording type and amount of food, emotions before and after eating and other behaviors. The participants are completing self-register daily during a week, and afterwards answer an acceptance and satisfaction questionnaire. This work is in progress at the moment. It is expected that the PDA system will show high levels of acceptance and satisfaction.

Spatiotemporal brain signal associated with high and low levels of proactive motor response inhibition.

Proactive motor response inhibition is used to strategically restrain actions in preparation for stopping. In this study, we first examined the event related potential (ERP) elicited by low and high level of proactive response inhibition, as assessed by the stop-signal task. Corroborating previous studies, we found an increased amplitude of the contingent negative variation (CNV) in the high level of proactive inhibition. As the main goal of the present study, swLORETA was used to determine the neural generators characterising CNV differences between low and high levels of proactive inhibition. Results showed that the higher level of proactive inhibition involved numerous generators, including within the middle and medial frontal gyrus. Importantly, we observed that the lower level of proactive inhibition also involved a specific neural generator, within the frontopolar cortex. Altogether, present findings identified the specific brain sources of ERP signals involved in the later phase of motor preparation under low or high levels of proactive motor response inhibition.

EEG Dynamics and Neural Generators in Implicit Navigational Image Processing in Adults with ADHD.

In contrast to childhood ADHD that is characterized by inattention, impulsivity and hyperactivity, most adults with ADHD predominantly exhibit inattention. We used a new oddball paradigm using implicit navigational images and analyzed EEG dynamics with swLORETA inverse modeling of the evoked potential generators to study cortical processing in adults with ADHD and age-matched controls. In passive observation, we demonstrated that P350 amplitude, alpha-beta oscillation event-related synchronization (ERS) anticipation, and beta event-related desynchronization (ERD) were significantly smaller in ADHD. In the active condition, P100 duration was reduced and N140 amplitude increased for both deviant and frequent conditions in the ADHD. Alpha ERS and delta-theta ERS were reduced in the ADHD in the deviant condition. The left somatosensory area (BA2) and the right parietal lobe (BA31, BA40) contributed more to the P100 generators in the control than in the ADHD group, while the left frontal lobe (BA10) contributed more to the P100 generators in the ADHD. The left inferior parietal lobe (BA40) contributed more to the N140 generators in the control than the ADHD group while the right posterior cingulate (BA30) contributed more to the N140 generators in the ADHD. These findings reinforce the notion that earlier cortical stages of visual processing are compromised in adult ADHD by inducing the emergence of different even-related potential generators and EEG dynamics in ADHD. Considering that classical approaches for ADHD diagnosis are based on qualitative clinical investigation possibly biased by subjectivity, EEG analysis is another objective tool that might contribute to diagnosis, future neurofeedback or brain stimulation therapies.

Enhanced metalloadsorption of bacterial cells displaying poly-His peptides.

The properties of Escherichia coli cells, acquired by cell surface presentation of one or two hexahistidine (His) clusters carried by the outer membrane LamB protein, have been examined. Strains producing LamB hybrids with the His chains accumulated greater than 11-fold more Cd2+ than E. coli cells expressing the protein without the His insert. Furthermore, the hexa-His chains on the cell surface caused cells to adhere reversibly to a Ni(2+)-containing solid matrix in a metal-dependent fashion. Thus, expression of poly-His peptides enables bacteria to act as a metalloaffinity adsorbent. These results open up the possibility for biosorption of heavy ions using engineered microorganisms.

Effect of gravity on human spontaneous 10-Hz electroencephalographic oscillations during the arrest reaction.

Electroencephalographic oscillations at 10 Hz (alpha and mu rhythms) are the most prominent rhythms observed in awake, relaxed (eye-closed) subjects. These oscillations may be considered as a marker of cortical inactivity or an index of the active inhibition of the sensory information. Different cortical sources may participate in the 10-Hz oscillation and appear to be modulated by the sensory context and functional demands. In microgravity, the marked reduction in multimodal graviceptive inputs to cortical networks participating in the representation of space could be expected to affect the 10-Hz activity. The effect of microgravity on this basic oscillation has heretofore not been studied quantitatively. Because the alpha rhythm has a functional role in the regulation of network properties of the visual areas, we hypothesised that the absence of gravity would affect its strength. Here, we report the results of an experiment conducted over the course of 3 space flights, in which we quantified the power of the 10-Hz activity in relation to the arrest reaction (i.e., in 2 distinct physiological states: eyes open and eyes closed). We observed that the power of the spontaneous 10-Hz oscillation recorded in the eyes-closed state in the parieto-occipital (alpha rhythm) and sensorimotor areas (mu rhythm) increased in the absence of gravity. The suppression coefficient during the arrest reaction and the related spectral perturbations produced by eye-opening/closure state transition also increased in on orbit. These results are discussed in terms of current theories on the source and the importance of the alpha rhythm for cognitive function.

Straightforward production of encoded microbeads by Flow Focusing: potential applications for biomolecule detection.

Fluorescently encoded polymeric microparticles are acquiring great importance in the development of simultaneous multianalyte screening assays. We have developed a very versatile and straightforward method for the production of dye-labeled microparticles with a very reproducible size distribution and freely-chosen and discernible fluorescent properties. Our method combines Flow Focusing technology with a solvent evaporation/extraction procedure in a single step, yielding spherical, non-aggregate and non-porous particles. We have designed a multi-coloured bead array which includes the possibility of modifying the surface properties of the microparticles, which offer excellent properties for covalent attachment of biomolecules such as peptides, oligonucleotides, proteins, etc. We also show the potential of the fluorescently labeled microspheres for the detection of biomolecule (peptides and oligonucelotides) interactions using flow cytometry.

Rational design of a bacterial transcriptional cascade for amplifying gene expression capacity.

Cascade regulatory circuits have been described that control numerous cell processes, and may provide models for the design of artificial circuits with novel properties. Here we describe the design of a transcriptional regulatory cascade to amplify the cell response to a given signal. We used the salicylate-responsive activators of Pseudomonas putida NahR of the naphthalene degradation plasmid NAH7 and XylS2, a mutant regulator of the TOL plasmid for catabolism of m-xylene and their respective cognate promoters Psal and PM: Control of the expression of xylS2 with the nahR/Psal system permitted either their selective activation with specific effectors for each protein or the simultaneous activation of both of them with salicylate. When cells face the common effector of the two regulators, both the increase in XylS2 concentration and the stimulation of its activity act synergistically on the PM: promoter, amplifying the gene expression capacity by at least one order of magnitude with respect to the individual systems. By changing the hierarchy of regulators, we showed that the specific features of the downstream regulator were crucial for the amplification effect. Directed changes in the effector profile of the regulators allowed the extension of the amplifying system to other molecular signals.

"Cerebellar contribution to visuo-attentional alpha rhythm: insights from weightlessness".

Human brain adaptation in weightlessness follows the necessity to reshape the dynamic integration of the neural information acquired in the new environment. This basic aspect was here studied by the electroencephalogram (EEG) dynamics where oscillatory modulations were measured during a visuo-attentional state preceding a visuo-motor docking task. Astronauts in microgravity conducted the experiment in free-floating aboard the International Space Station, before the space flight and afterwards. We observed stronger power decrease (~ERD: event related desynchronization) of the ~10 Hz oscillation from the occipital-parietal (alpha ERD) to the central areas (mu ERD). Inverse source modelling of the stronger alpha ERD revealed a shift from the posterior cingulate cortex (BA31, from the default mode network) on Earth to the precentral cortex (BA4, primary motor cortex) in weightlessness. We also observed significant contribution of the vestibular network (BA40, BA32, and BA39) and cerebellum (lobule V, VI). We suggest that due to the high demands for the continuous readjustment of an appropriate body posture in free-floating, this visuo-attentional state required more contribution from the motor cortex. The cerebellum and the vestibular network involvement in weightlessness might support the correction signals processing necessary for postural stabilization, and the increased demand to integrate incongruent vestibular information.

Sensorimotor and cognitive involvement of the beta-gamma oscillation in the frontal N30 component of somatosensory evoked potentials.

The most consistent negative cortical component of somatosensory evoked potentials (SEPs), namely the frontal N30, can be considered more multidimensional than a strict item of standard somatosensory investigation, dedicated to tracking the afferent volley from the peripheral sensory nerve potentials to the primary somatosensory cortex. In this review, we revisited its classical sensorimotor implication within the framework of the recent oscillatory model of ongoing electroencephalogram (EEG) rhythms. Recently, the N30 component was demonstrated to be related to an increase in the power of beta-gamma EEG oscillation and a phase reorganization of the ongoing EEG oscillations (phase locking) in this frequency band. Thanks to high density EEG recordings and the inverse modeling method (swLORETA), it was shown that different overlapping areas of the motor and premotor cortex are specifically involved in generating the N30 in the form of a beta gamma oscillatory phase locking and power increase. This oscillatory approach has allowed a re-investigation of the movement gating behavior of the N30. It was demonstrated that the concomitant execution of finger movements by a stimulated hand impinges the temporal concentration of the ongoing beta/gamma EEG oscillations and abolished the N30 component. It was hypothesized that the involvement of neuronal populations in both the sensorimotor cortex and other related areas were unable to respond to the phasic sensory activation so could not phase-lock their oscillatory signals to the external sensory input during the movement. In this case, the actual movement has primacy over the artificial somatosensory input. The contribution of the ongoing oscillatory activity in the N30 emergence calls for a reappraisal of fundamental and clinical interpretations of the frontal N30 component. An absent or reduced amplitude of the N30 can now be viewed not only as a deficit in the activation of the somatosensory synaptic network in response to sensory input, but also as a global alteration of the beta-gamma ongoing oscillation and/or of the phase-locking mechanism itself. In addition, it has lately been shown that the N30 amplitude increases during the observation of another person's hand movement. A new paradigm in which the experimenter's hand movement, observed by the participant, triggered the electric stimulation of the subject's hand has been introduced. This has allowed the identification of different cortical areas which are closely related to those involved in the mirror neuron system. This contribution of N30 behavior has paved the way for future investigation of the integration of sensory input into cognitive context.

The implementation of mindfulness in healthcare systems: a theoretical analysis.

OBJECTIVE: Evidence regarding the efficacy of mindfulness-based interventions (MBIs) is increasing exponentially; however, there are still challenges to their integration in healthcare systems. Our goal is to provide a conceptual framework that addresses these challenges in order to bring about scholarly dialog and support health managers and practitioners with the implementation of MBIs in healthcare. METHOD: This is an opinative narrative review based on theoretical and empirical data that address key issues in the implementation of mindfulness in healthcare systems, such as the training of professionals, funding and costs of interventions, cost effectiveness and innovative delivery models. RESULTS: We show that even in the United Kingdom, where mindfulness has a high level of implementation, there is a high variability in the access to MBIs. In addition, we discuss innovative approaches based on "complex interventions," "stepped-care" and "low intensity-high volume" concepts that may prove fruitful in the development and implementation of MBIs in national healthcare systems, particularly in Primary Care. CONCLUSION: In order to better understand barriers and opportunities for mindfulness implementation in healthcare systems, it is necessary to be aware that MBIs are "complex interventions," which require innovative approaches and delivery models to implement these interventions in a cost-effective and accessible way.