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Restoration and rehabilitation of native species in the Laurentian Great Lakes is a priority for fisheries management agencies. Restoration efforts are increasingly incorporating a perspective that considers species within a broader food web context. We used stable isotope analysis and museum-preserved specimens to describe and quantify 100 years of food web changes in the Lake Superior fish community. We validated stable isotope analysis of museum specimens by showing a positive correlation between isotope- and diet-based estimates of trophic position. While introductions have created a more trophically diverse food web than historically found in Lake Superior, two separate metrics revealed little community- wide change in the food web. Our species-specific analysis revealed trophic niche differences between shortjaw (Coregonus zenithicus) and shortnose (Coregonus reighardi) ciscoes, two species previously argued to be indistinguishable based on morphological characteristics. By providing a historical context, our findings show the ability of the Lake Superior food web to accommodate non-native species introductions over the last century while still supporting native species populations. This long-term information about food web structure can help guide management and restoration goals in Lake Superior. Furthermore, Lake Superior can serve as a basis for comparing food web changes in other, more highly altered Great Lakes. Resume: La restauration et la rehabilitation des especes indigenes dans les Grands Lacs laurentiens sont une priorite pour les agences de gestion des peches. Les efforts de restauration incorporent de plus en plus une perspective qui considere les especes dans le contexte d'un reseau alimentaire elargi. Nous avons utilise des analyses d'isotopes stables et des specimens conserves dans des musees pour decrire et mesurer les changements au cours de 100 ans dans les reseaux alimentaires de la communaute de poissons du lac Superieur. Nous avons valide l'analyse des isotopes stables des specimens de musee en montrant une correlation positive entre les estimations de la position trophique basees sur les isotopes et sur le regime alimentaire. Alors que les introductions ont cree un reseau alimentaire de plus grande diversite trophique que dans le passe dans le lac Superieur, deux metriques differentes revelent peu de changements a l'echelle de la communaute dans le reseau alimentaire. Notre analyse specifique a l'espece montre des differences de niche tropique entre les ciscos a machoires egales (Coregonus zenithicus) et les ciscos a museau court (Coregonus reighardi), deux especes considerees anterieurement comme impossibles a distinguer par leurs caracteres morphologiques. En fournissant ce contexte historique, nos resultats demontrent la capacite du reseau alimentaire du lac Superieur a s'accommoder des introductions d'especes non indigenes au cours du dernier siecle, tout en soutenant les populations d'especes indigenes. Cette information sur une longue periode concernant la structure du reseau alimentaire peut servir a guider les objectifs de gestion et de restauration au lac Superieur. De plus, le lac Superieur peut servir de point de comparaison pour les changements de reseau alimentaire dans les autres Grands Lacs plus fortement modifies. [Traduit par la Redaction], Introduction The combined effects of species introductions and over-fishing over the last century have resulted in the extirpation of many native fish species in the Laurentian Great Lakes (Lawrie and [...]

Resource polymorphisms are widely observed in fishes; however, ontogenetic contributions to morphological and ecological differences are poorly understood. This study examined whether ontogenetic changes in niche partitioning could explain morphological and buoyancy differences between lake trout (Salvelinus namaycush) morphotypes in Great Slave Lake (Northwest Territories, Canada). Morphometric analysis, buoyancy, capture depth, diet, and stable isotope data were used in concert to determine whether (i) differences occur in small, as well as large, lake trout, (ii) ontogenetic changes in morphology and buoyancy correlate with shifts in depth or diet, and (iii) a subset of small trout, putatively identified as 'bumpers', are distinct from other morphotypes. Ontogenetic changes in lake trout morphology were associated with an ecological shift between benthic and pelagic feeding. Resource partitioning between lean and siscowet-like trout occurred within benthic (small trout) and pelagic (large trout) habitats. The bumper subset did not differ from small siscowet-like trout. By combining multiple methods and an ontogenetic perspective, our study provides novel perspectives on resource polymorphisms in large, deep lakes and on existing interpretations of stable isotope data from large lakes in general. Le polymorphisme des ressources est un phenomene frequemment observe chez les poissons; cependant, les contributions ontogeniques aux differences morphologiques et ecologiques restent mal comprises. Notre etude examine si les changements ontogeniques de partition de niche peuvent expliquer les differences de morphologie et de flottabilite entre les morphotypes de touladis dans le Grand Lac des Esclaves (Territoires du Nord-Ouest, Canada). Une analyse morphometrique, ainsi que des donnees sur la flottabilite, la profondeur de capture, le regime alimentaire et les isotopes stables, nous ont servi tout ensemble a determiner (i) si les differences se retrouvent a la fois chez les touladis de petite et de grande taille, (ii) s'il y a une correlation entre les changements de morphologie et de flottabilite et les modifications de profondeur ou de regime alimentaire et (iii) si un sous-ensemble de touladis de petite taille, presumes etre des << bossus >>, se distingue des autres morphotypes. Les changements ontologiques chez les touladis sont associes a une modification de l'alimentation, de benthique a pelagique. La partition des ressources entre les touladis maigres et les touladis d'allure siscowet se produit dans les habitats benthiques (petits touladis) et pelagiques (grands touladis). Le sous-ensemble des bossus ne differe pas des petits touladis de type siscowet. En combinant plusieurs methodes et utilisant une approche ontogenique, notre etude offre des perspectives inedites sur le polymorphisme des ressources dans des lacs profonds de grande taille et sur les interpretations actuelles des donnees d'isotopes stables dans les grands lacs en general. [Traduit par la Redaction], Introduction In recently deglaciated lakes, adaptive radiations of fishes are attributed to high intraspecific competition and open available niches (Robinson and Wilson 1994). Resource polymorphisms, defined as morphologically distinct 'types' [...]

There is accumulating evidence for deficits in the perception and regulation of one's own emotions, as well as the recognition of others' emotions in somatic symptom disorder (SSD). However, investigations of SSD focusing on specific aspects of emotion processing and how these might interact are missing. We included 35 patients with SSD and 35 healthy controls who completed questionnaires on the perception and regulation of their own emotions, as well as experimental investigations of emotion recognition and trust. In line with previous studies, our results show that SSD patients in comparison to healthy controls have difficulties in the identification and description of own feelings (ηp2 = .381 and ηp2 = .315). Furthermore, we found that patients apply less cognitive reappraisal (ηp2 = .185) but tend to use more expressive suppression (ηp2 = .047). In contrast to previous studies, we found SSD patients to perform superior in emotion recognition, in particular for anger (d = 0.40). In addition, patients with SSD invested less in a trust game (d = 0.73). These results point to a higher sensitivity for negative emotions and less trust in others. Further, these findings suggest a dissociation between the ability to recognize one's own emotions versus others' emotions in SSD. Future interventions targeting emotion processing in SSD might focus on the identification of one's own emotions, prior to the training of emotion regulation. [ABSTRACT FROM AUTHOR]

Understanding the subprocesses of risky decision making is a prerequisite for understanding (dys-)functional decisions. For the present fMRI study, we designed a novel variant of the balloon-analog-risk task (BART) that measures three phases: decision making, reward anticipation, and feedback processing. Twenty-nine healthy young adults completed the BART. We analyzed neural activity and functional connectivity. Parametric modulation allowed assessing changes in brain functioning depending on the riskiness of the decision. Our results confirm involvement of nucleus accumbens, insula, anterior cingulate cortex, and dorsolateral prefrontal cortex in all subprocesses of risky decision-making. In addition, subprocesses were differentiated by the strength of activation in these regions, as well as by changes in activity and nucleus accumbens-connectivity by the riskiness of the decision. The presented fMRI-BART variant allows distinguishing activity and connectivity during the subprocesses of risky decision making and shows how activation and connectivity patterns relate to the riskiness of the decision. Hence, it is a useful tool for unraveling impairments in subprocesses of risky decision making in people with high risk behavior., (© 2024 The Author(s). Psychophysiology published by Wiley Periodicals LLC on behalf of Society for Psychophysiological Research.)

Background: Depression is related to default mode network (DMN) connectivity and higher respiration pattern variability (RPV). In addition, DMN connectivity and RPV are interrelated and predict a poorer clinical course of depression. The association of RPV and depression might further be boosted by anxiety levels. Aim of the present study was to investigate whether a mindfulness-based training in emotionally challenged remitted depressed participants (rMDD) leads to reduced DMN connectivity and lower RPV, and if RPV interacts with anxiety levels., Methods: To challenge participants, sad mood was induced with keywords of personal negative life events in 49 rMDD during fMRI before and after a 4-week mindfulness-based attention training (MBAT) or progressive muscle relaxation. Respiration was measured by means of a built-in respiration belt., Results: After both trainings, rMDD showed no significant changes in DMN connectivity. However, MBAT was effective in reducing the RPV which was related to lower anxiety levels especially in high anxious individuals., Conclusions: RPV can be influenced by training which may hint to an underlying biological pathway of training effects. Importantly, these effects seem to be associated with anxiety levels. Therefore, respiration focused training might be an important tool assisting the treatment of depression and anxiety., (© 2020 The Authors.)

Our ability to infer other individuals' emotions is central for successful social interactions. Based on the theory of embodied simulation, our mirror neuron system (MNS) provides the essential link between the observed facial configuration of another individual and our inference of the emotion by means of common neuronal activation. However, so far it is unknown, whether the MNS differentiates the valence of facial configurations. To increase the precision of our fMRI measurement, we used an adaptation design, which allows insights into whether the same neuronal population is active for subsequent stimuli of facial configurations. 76 participants were shown congruent, or incongruent consecutive pairs of facial configurations expressing fear or happiness. Significant activation for changes in emotional valence from adaptor to target was revealed in fusiform gyrus, superior temporal sulcus, amygdala, insula, inferior parietal lobe and Brodmann area 44. In addition, activation change was higher in superior temporal sulcus, insula and inferior frontal gyrus for a switch from happiness to fear than for fear to happiness. Our results suggest an involvement of the MNS in valence discrimination, and a higher sensitivity of the MNS to negative than positive valence. These findings point to a role of the MNS that goes beyond the mere coding of a motor state., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Real-time functional magnetic resonance imaging neurofeedback (rtfMRI NFB) is a promising method for targeted regulation of pathological brain processes in mental disorders. But most NFB approaches so far have used relatively restricted regional activation as a target, which might not address the complexity of the underlying network changes. Aiming towards advancing novel treatment tools for disorders like schizophrenia, we developed a large-scale network functional connectivity-based rtfMRI NFB approach targeting dorsolateral prefrontal cortex and anterior cingulate cortex connectivity with the striatum. In a double-blind randomized yoke-controlled single-session feasibility study with N ​= ​38 healthy controls, we identified strong associations between our connectivity estimates and physiological parameters reflecting the rate and regularity of breathing. These undesired artefacts are especially detrimental in rtfMRI NFB, where the same data serves as an online feedback signal and offline analysis target. To evaluate ways to control for the identified respiratory artefacts, we compared model-based physiological nuisance regression and global signal regression (GSR) and found that GSR was the most effective method in our data. Our results strongly emphasize the need to control for physiological artefacts in connectivity-based rtfMRI NFB approaches and suggest that GSR might be a useful method for online data correction for respiratory artefacts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)