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A Proposed Chaperone of the Bacterial Type VI Secretion System Functions To Constrain a Self-Identity Protein. J Bacteriol 2018; 200:JB.00688-17. [PMID: 29555703 DOI: 10.1128/jb.00688-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 03/15/2018] [Indexed: 01/01/2023] Open
Abstract
The bacterium Proteus mirabilis can communicate identity through the secretion of the self-identity protein IdsD via the type VI secretion (T6S) system. IdsD secretion is essential for self-versus-nonself recognition behaviors in these populations. Here we provide an answer to the unresolved question of how the activity of a T6S substrate, such as IdsD, is regulated before secretion. We demonstrate that IdsD is found in clusters that form independently of the T6S machinery and activity. We show that the IdsC protein, which is a member of the proposed DUF4123 chaperone family, is essential for the maintenance of these clusters and of the IdsD protein itself. We provide evidence that amino acid disruptions in IdsC are sufficient to disrupt IdsD secretion but not IdsD localization into subcellular clusters, strongly supporting the notion that IdsC functions in at least two different ways: maintaining IdsD levels and secreting IdsD. We propose that IdsC, and likely other DUF4123-containing proteins, functions to regulate T6S substrates in the donor cell both by maintaining protein levels and by mediating secretion at the T6S machinery.IMPORTANCE Understanding the subcellular dynamics of self-identity proteins is crucial for developing models of self-versus-nonself recognition. We directly addressed how a bacterium restricts self-identity information before cell-cell exchange. We resolved two conflicting models for type VI secretion (T6S) substrate regulation by focusing on the self-identity protein IdsD. One model is that a cognate immunity protein binds the substrate, inhibiting activity before transport. Another model proposes that DUF4123 proteins act as chaperones in the donor cell, but no detailed molecular mechanism was previously known. We resolve this discrepancy and propose a model wherein a chaperone couples IdsD sequestration with its localization. Such a molecular mechanism restricts the communication of identity, and possibly other T6S substrates, in producing cells.
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Carter R, Cust F, Boath E. Peer support workers' experiences of supporting women with postnatal depression: a constant comparative exploration. J Reprod Infant Psychol 2018. [PMID: 29517347 DOI: 10.1080/02646838.2017.1416336] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
OBJECTIVE To explore the lived experiences of peer support workers (PSWs) during their intervention with mothers suffering from postnatal depression (PND). BACKGROUND Postnatal depression is a major public health concern affecting approximately 13% of women worldwide. There is evidence within recent literature that peer support may have a positive effect upon women suffering with PND. METHODS Written data from the PSW's logbooks, interviews and supervisory sessions was collected and thematically analysed. RESULTS Data were analysed using a constant comparative method and four key themes emerged. These were: changing perspectives of the PSW, their personal self-analysis and recognition, concern about the abandonment of the women that they had been supporting and self-recovery from postnatal depression. CONCLUSION Findings indicate that PSWs choose to offer support based upon their own experiences, rejecting formal counselling therapies. This study found that peer-designed interventions do appear to have some merit.
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Luo J, Chen K, Yin P, Li T, Wan G, Zhang J, Ye S, Bi X, Pang Y, Wei Y, Liu T. Effect of Cation-π Interaction on Macroionic Self-Assembly. Angew Chem Int Ed Engl 2018; 57:4067-4072. [PMID: 29441703 DOI: 10.1002/anie.201800409] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2018] [Indexed: 01/29/2023]
Abstract
A series of rod-shaped polyoxometalates (POMs) [Bu4 N]7 [Mo6 O18 NC(CH2 O)3 MnMo6 O18 (OCH2 )3 CNMo6 O18 ] and [Bu4 N]7 [ArNMo6 O17 NC(CH2 O)3 MnMo6 O18 (OCH2 )3 CNMo6 O17 NAr] (Ar=2,6-dimethylphenyl, naphthyl and 1-methylnaphthyl) were chosen to study the effects of cation-π interaction on macroionic self-assembly. Diffusion ordered spectroscopy (DOSY) and isothermal titration calorimetry (ITC) techniques show that the binding affinity between the POMs and Zn2+ ions is enhanced significantly after grafting aromatic groups onto the clusters, leading to the effective replacement of tetrabutylammonium counterions (TBAs) upon the addition of ZnCl2 . The incorporation of aromatic groups results in the significant contribution of cation-π interaction to the self-assembly, as confirmed by the opposite trend of assembly size vs. ionic strength when compared with those without aromatic groups. The small difference between two aromatic groups toward the Zn2+ ions is amplified after combining with the clusters, which consequently triggers the self-recognition behavior between two highly similar macroanions.
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Abstract
Many bacteria, both environmental and pathogenic, exhibit the property of autoaggregation. In autoaggregation (sometimes also called autoagglutination or flocculation), bacteria of the same type form multicellular clumps that eventually settle at the bottom of culture tubes. Autoaggregation is generally mediated by self-recognising surface structures, such as proteins and exopolysaccharides, which we term collectively as autoagglutinins. Although a widespread phenomenon, in most cases the function of autoaggregation is poorly understood, though there is evidence to show that aggregating bacteria are protected from environmental stresses or host responses. Autoaggregation is also often among the first steps in forming biofilms. Here, we review the current knowledge on autoaggregation, the role of autoaggregation in biofilm formation and pathogenesis, and molecular mechanisms leading to aggregation using specific examples.
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Physiological Heterogeneity Triggers Sibling Conflict Mediated by the Type VI Secretion System in an Aggregative Multicellular Bacterium. mBio 2018; 9:mBio.01645-17. [PMID: 29437919 PMCID: PMC5801462 DOI: 10.1128/mbio.01645-17] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
A hallmark of social microorganisms is their ability to engage in complex and coordinated behaviors that depend on cooperative and synchronized actions among many cells. For instance, myxobacteria use an aggregation strategy to form multicellular, spore-filled fruiting bodies in response to starvation. One barrier to the synchronization process is physiological heterogeneity within clonal populations. How myxobacteria cope with these physiological differences is poorly understood. Here, we investigated the interactions between closely related but physiologically distinct Myxococcus xanthus populations. We used a genetic approach to create amino acid auxotrophs and tested how they interact with a parental prototroph strain. Importantly, we found that auxotrophs were killed by their prototroph siblings when the former were starved for amino acids but not when grown on rich medium or when both strains were starved. This antagonism depended on the type VI secretion system (T6SS) as well as gliding motility; in particular, we identified the effector-immunity pair (TsxEI) as the mediator of this killing. This sibling antagonism resulted from lower levels of the TsxI immunity protein in the starved population. Thus, when starving auxotrophs were mixed with nonstarving prototrophs, the auxotrophs were susceptible to intoxication by the TsxE effector delivered by the T6SS from the prototrophs. Furthermore, our results suggested that homogeneously starving populations have reduced T6SS activity and, therefore, do not antagonize each other. We conclude that heterogeneous populations of M. xanthus use T6SS-dependent killing to eliminate starving or less-fit cells, thus facilitating the attainment of homeostasis within a population and the synchronization of behaviors. Social bacteria employ elaborate strategies to adapt to environmental challenges. One means to prepare for unpredictable changes is for clonal populations to contain individuals with diverse physiological states. These subpopulations will differentially respond to new environmental conditions, ensuring that some cells will better adapt. However, for social bacteria physiological heterogeneity may impede the ability of a clonal population to synchronize their behaviors. By using a highly cooperative and synchronizable model organism, M. xanthus, we asked how physiological differences between interacting siblings impacted their collective behaviors. Physiological heterogeneity was experimentally designed such that one population starved while the other grew when mixed. We found that these differences led to social conflict where more-fit individuals killed their less-fit siblings. For the first time, we report that the T6SS nanoweapon mediates antagonism between siblings, resulting in myxobacterial populations becoming more synchronized to conduct social behaviors.
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Bayersdorf R, Fruscalzo A, Catania F. Linking autoimmunity to the origin of the adaptive immune system. EVOLUTION MEDICINE AND PUBLIC HEALTH 2018; 2018:2-12. [PMID: 29423226 PMCID: PMC5793817 DOI: 10.1093/emph/eoy001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
In jawed vertebrates, the adaptive immune system (AIS) cooperates with the innate immune system (IIS) to protect hosts from infections. Although targeting non-self-components, the AIS also generates self-reactive antibodies which, when inadequately counter-selected, can give rise to autoimmune diseases (ADs). ADs are on the rise in western countries. Why haven’t ADs been eliminated during the evolution of a ∼500 million-year old system? And why have they become more frequent in recent decades? Self-recognition is an attribute of the phylogenetically more ancient IIS and empirical data compellingly show that some self-reactive antibodies, which are classifiable as elements of the IIS rather then the AIS, may protect from (rather than cause) ADs. Here, we propose that the IIS’s self-recognition system originally fathered the AIS and, as a consequence of this relationship, its activity is dampened in hygienic environments. Rather than a mere breakdown or failure of the mechanisms of self-tolerance, ADs might thus arise from architectural constraints.
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Wójcik MJ, Nowicka MM, Kotlewska I, Nowicka A. Self-face Captures, Holds, and Biases Attention. Front Psychol 2018; 8:2371. [PMID: 29375456 PMCID: PMC5768651 DOI: 10.3389/fpsyg.2017.02371] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2017] [Accepted: 12/28/2017] [Indexed: 11/13/2022] Open
Abstract
The implicit self-recognition process may take place already in the pre-attentive stages of perception. After a silent stimulus has captured attention, it is passed on to the attentive stage where it can affect decision making and responding. Numerous studies show that the presence of self-referential information affects almost every cognitive level. These effects may share a common and fundamental basis in an attentional mechanism, conceptualized as attentional bias: the exaggerated deployment of attentional resources to a salient stimulus. A gold standard in attentional bias research is the dot-probe paradigm. In this task, a prominent stimulus (cue) and a neutral stimulus are presented in different spatial locations, followed by the presentation of a target. In the current study we aimed at investigating whether the self-face captures, holds and biases attention when presented as a task-irrelevant stimulus. In two dot-probe experiments coupled with the event-related potential (ERP) technique we analyzed the following relevant ERPs components: N2pc and SPCN which reflect attentional shifts and the maintenance of attention, respectively. An inter-stimulus interval separating face-cues and probes (800 ms) was introduced only in the first experiment. In line with our predictions, in Experiment 1 the self-face elicited the N2pc and the SPCN component. In Experiment 2 in addition to N2pc, an attentional bias was observed. Our results indicate that unintentional self-face processing disables the top-down control setting to filter out distractors, thus leading to the engagement of attentional resources and visual short-term memory.
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Hecht EE, Mahovetz LM, Preuss TM, Hopkins WD. A neuroanatomical predictor of mirror self-recognition in chimpanzees. Soc Cogn Affect Neurosci 2017; 12:37-48. [PMID: 27803287 PMCID: PMC5390703 DOI: 10.1093/scan/nsw159] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 10/17/2016] [Indexed: 11/12/2022] Open
Abstract
The ability to recognize one's own reflection is shared by humans and only a few other species, including chimpanzees. However, this ability is highly variable across individual chimpanzees. In humans, self-recognition involves a distributed, right-lateralized network including frontal and parietal regions involved in the production and perception of action. The superior longitudinal fasciculus (SLF) is a system of white matter tracts linking these frontal and parietal regions. The current study measured mirror self-recognition (MSR) and SLF anatomy in 60 chimpanzees using diffusion tensor imaging. Successful self-recognition was associated with greater rightward asymmetry in the white matter of SLFII and SLFIII, and in SLFIII's gray matter terminations in Broca's area. We observed a visible progression of SLFIII's prefrontal extension in apes that show negative, ambiguous, and compelling evidence of MSR. Notably, SLFIII's terminations in Broca's area are not right-lateralized or particularly pronounced at the population level in chimpanzees, as they are in humans. Thus, chimpanzees with more human-like behavior show more human-like SLFIII connectivity. These results suggest that self-recognition may have co-emerged with adaptations to frontoparietal circuitry.
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Abstract
Clustered protocadherins (Pcdhs) mediate numerous neural patterning functions, including neuronal self-recognition and non-self-discrimination to direct self-avoidance among vertebrate neurons. Individual neurons stochastically express a subset of Pcdh isoforms, which assemble to form a stochastic repertoire of cis-dimers. We describe the structure of a PcdhγB7 cis-homodimer, which includes the membrane-proximal extracellular cadherin domains EC5 and EC6. The structure is asymmetric with one molecule contributing interface surface from both EC5 and EC6, and the other only from EC6. Structural and sequence analyses suggest that all Pcdh isoforms will dimerize through this interface. Site-directed mutants at this interface interfere with both Pcdh cis-dimerization and cell surface transport. The structure explains the known restrictions of cis-interactions of some Pcdh isoforms, including α-Pcdhs, which cannot form homodimers. The asymmetry of the interface approximately doubles the size of the recognition repertoire, and restrictions on cis-interactions among Pcdh isoforms define the limits of the Pcdh recognition unit repertoire.
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Hirata S, Fuwa K, Myowa M. Chimpanzees recognize their own delayed self-image. ROYAL SOCIETY OPEN SCIENCE 2017; 4:1-9. [PMID: 28878955 PMCID: PMC5579101 DOI: 10.1098/rsos.170370] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2017] [Accepted: 07/10/2017] [Indexed: 06/01/2023]
Abstract
Unlike mirror self-recognition, recognizing one's own image in delayed video footage may indicate the presence of a concept of self that extends across time and space. While humans typically show this ability around 4 years of age, it is unknown whether this capacity is found in non-human animals. In this study, chimpanzees performed a modified version of the mark test to investigate whether chimpanzees could remove stickers placed on the face and head while watching live and delayed video images. The results showed that three of five chimpanzees consistently removed the mark in delayed-viewing conditions, while they removed the stickers much less frequently in control video conditions which lacked a link to their current state. These findings suggest that chimpanzees, like human children at the age of 4 years and more, can comprehend temporal dissociation in their concept of self.
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Marotta A, Bombieri F, Zampini M, Schena F, Dallocchio C, Fiorio M, Tinazzi M. The Moving Rubber Hand Illusion Reveals that Explicit Sense of Agency for Tapping Movements Is Preserved in Functional Movement Disorders. Front Hum Neurosci 2017. [PMID: 28634447 PMCID: PMC5459911 DOI: 10.3389/fnhum.2017.00291] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Functional movement disorders (FMD) are characterized by motor symptoms (e.g., tremor, gait disorder, and dystonia) that are not compatible with movement abnormalities related to a known organic cause. One key clinical feature of FMD is that motor symptoms are similar to voluntary movements but are subjectively experienced as involuntary by patients. This gap might be related to abnormal self-recognition of bodily action, which involves two main components: sense of agency and sense of body ownership. The aim of this study was to systematically investigate whether this function is altered in FMD, specifically focusing on the subjective feeling of agency, body ownership, and their interaction during normal voluntary movements. Patients with FMD (n = 21) and healthy controls (n = 21) underwent the moving Rubber Hand Illusion (mRHI), in which passive and active movements can differentially elicit agency, ownership or both. Explicit measures of agency and ownership were obtained via a questionnaire. Patients and controls showed a similar pattern of response: when the rubber hand was in a plausible posture, active movements elicited strong agency and ownership; implausible posture of the rubber hand abolished ownership but not agency; passive movements suppressed agency but not ownership. These findings suggest that explicit sense of agency and body ownership are preserved in FMD. The latter finding is shared by a previous study in FMD using a static version of the RHI, whereas the former appears to contrast with studies demonstrating altered implicit measures of agency (e.g., sensory attenuation). Our study extends previous findings by suggesting that in FMD: (i) the sense of body ownership is retained also when interacting with the motor system; (ii) the subjective experience of agency for voluntary tapping movements, as measured by means of mRHI, is preserved.
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Berry JA, Parker AC. The Elephant in the Mirror: Bridging the Brain's Explanatory Gap of Consciousness. Front Syst Neurosci 2017; 10:108. [PMID: 28111543 PMCID: PMC5216024 DOI: 10.3389/fnsys.2016.00108] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 12/19/2016] [Indexed: 11/29/2022] Open
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Vassallo CN, Cao P, Conklin A, Finkelstein H, Hayes CS, Wall D. Infectious polymorphic toxins delivered by outer membrane exchange discriminate kin in myxobacteria. eLife 2017; 6:29397. [PMID: 28820387 PMCID: PMC5562445 DOI: 10.7554/elife.29397] [Citation(s) in RCA: 56] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2017] [Accepted: 07/13/2017] [Indexed: 01/07/2023] Open
Abstract
Myxobacteria are known for complex social behaviors including outer membrane exchange (OME), in which cells exchange large amounts of outer membrane lipids and proteins upon contact. The TraA cell surface receptor selects OME partners based on a variable domain. However, traA polymorphism alone is not sufficient to precisely discriminate kin. Here, we report a novel family of OME-delivered toxins that promote kin discrimination of OME partners. These SitA lipoprotein toxins are polymorphic and widespread in myxobacteria. Each sitA is associated with a cognate sitI immunity gene, and in some cases a sitB accessory gene. Remarkably, we show that SitA is transferred serially between target cells, allowing the toxins to move cell-to-cell like an infectious agent. Consequently, SitA toxins define strong identity barriers between strains and likely contribute to population structure, maintenance of cooperation, and strain diversification. Moreover, these results highlight the diversity of systems evolved to deliver toxins between bacteria.
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Porciello G, Minio-Paluello I, Bufalari I. Commentary: Attentional control and the self: The Self Attention Network (SAN). Front Psychol 2016; 7:1701. [PMID: 27857699 PMCID: PMC5093136 DOI: 10.3389/fpsyg.2016.01701] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 10/14/2016] [Indexed: 12/17/2022] Open
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Gonzalez-Franco M, Bellido AI, Blom KJ, Slater M, Rodriguez-Fornells A. The Neurological Traces of Look-Alike Avatars. Front Hum Neurosci 2016; 10:392. [PMID: 27536228 PMCID: PMC4971066 DOI: 10.3389/fnhum.2016.00392] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2016] [Accepted: 07/21/2016] [Indexed: 12/25/2022] Open
Abstract
We designed an observational study where participants (n = 17) were exposed to pictures and look-alike avatars pictures of themselves, a familiar friend or an unfamiliar person. By measuring participants’ brain activity with electroencephalography (EEG), we found face-recognition event related potentials (ERPs) in the visual cortex, around 200–250 ms, to be prominent for the different familiarity levels. A less positive component was found for self-recognized pictures (P200) than pictures of others, showing similar effects in both real faces and look-alike avatars. A rapid adaptation in the same component was found when comparing the neural processing of avatar faces vs. real faces, as if avatars in general were assimilated as real face representations over time. ERP results also showed that in the case of the self-avatar, the P200 component correlated with more complex conscious encodings of self-representation, i.e., the difference in voltage in the P200 between the self-avatar and the self-picture was reduced in participants that felt the avatar looked like them. This study is put into context within the literature of self-recognition and face recognition in the visual cortex. Additionally, the implications of these results on look-alike avatars are discussed both for future virtual reality (VR) and neuroscience studies.
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Gratwick-Sarll K, Bentley C, Harrison C, Mond J. Poor self-recognition of disordered eating among girls with bulimic-type eating disorders: cause for concern? Early Interv Psychiatry 2016; 10:316-23. [PMID: 25112818 DOI: 10.1111/eip.12168] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/13/2014] [Accepted: 06/19/2014] [Indexed: 11/27/2022]
Abstract
AIM Bulimic-type eating disorders are common among young women and associated with high levels of distress and disability and low uptake of mental health care. We examined self-recognition of disordered eating and factors associated with this among female adolescents with bulimic-type eating disorders (n = 139) recruited from a large, population-based sample. METHODS A vignette of a fictional character with bulimia nervosa was presented, followed by a series of questions addressing the nature and treatment of the problem described. One of these questions required participants to indicate whether they currently had a problem such as the one described. Self-report measures of eating disorder symptoms, general psychological distress and quality of life were also completed. RESULTS More than half of participants (58%) did not believe that they currently had a problem with their eating. In multivariable analysis, impairment in emotional well-being and self-induced vomiting were the only variables independently associated with self-recognition. Participants who recognized a problem with their eating were more likely to have sought treatment for an eating problem than those who did not. CONCLUSIONS Recognition of disordered eating among adolescents with bulimic-type eating disorders may be poor and this may be a factor in low uptake of mental health care. Health promotion efforts may need to address the misconception that only bulimic-type disorders involving self-induced vomiting are pathological.
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Khatchatourov A, Pachet F, Rowe V. Action Identity in Style Simulation Systems: Do Players Consider Machine-Generated Music As of Their Own Style? Front Psychol 2016; 7:474. [PMID: 27199788 PMCID: PMC4859091 DOI: 10.3389/fpsyg.2016.00474] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 03/17/2016] [Indexed: 11/13/2022] Open
Abstract
The generation of musical material in a given style has been the subject of many studies with the increased sophistication of artificial intelligence models of musical style. In this paper we address a question of primary importance for artificial intelligence and music psychology: can such systems generate music that users indeed consider as corresponding to their own style? We address this question through an experiment involving both performance and recognition tasks with musically naïve school-age children. We asked 56 children to perform a free-form improvisation from which two kinds of music excerpt were created. One was a mere recording of original performances. The other was created by a software program designed to simulate the participants' style, based on their original performances. Two hours after the performance task, the children completed the recognition task in two conditions, one with the original excerpts and one with machine-generated music. Results indicate that the success rate is practically equivalent in two conditions: children tended to make correct attribution of the excerpts to themselves or to others, whether the music was human-produced or machine-generated (mean accuracy = 0.75 and = 0.71, respectively). We discuss this equivalence in accuracy for machine-generated and human produced music in the light of the literature on memory effects and action identity which addresses the recognition of one's own production.
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Fisher-Phelps ML, Mendoza SP, Serna S, Griffin LL, Schaefer TJ, Jarcho MR, Ragen BJ, Goetze LR, Bales KL. Laboratory simulations of mate-guarding as a component of the pair-bond in male titi monkeys, Callicebus cupreus. Am J Primatol 2016; 78:573-82. [PMID: 26375708 PMCID: PMC5657484 DOI: 10.1002/ajp.22483] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 08/25/2015] [Accepted: 09/07/2015] [Indexed: 01/29/2023]
Abstract
Mate-guarding and territorial aggression (both intra- and inter-sexual) are behavioral components of social monogamy seen in male coppery titi monkeys (Callicebus cupreus) both in the field and in the laboratory. Methodology for studying these behaviors in captivity facilitates the translation of questions between field and laboratory. In this study, we tested whether exposure to a mirror would stimulate mate-guarding behavior in male titi monkeys, and whether this exposure was accompanied by hormonal changes. Eight males were exposed to a mirror condition (treatment) or the back of the mirror (control) for five sessions, and behavioral responses were filmed. Blood samples were taken to measure levels of cortisol, oxytocin, and vasopressin. Lipsmacks (P < 0.0001), arching (P < 0.0001), tail-lashing (P = 0.009), restraining (P = 0.015), and approaches to the female (P = 0.0002) were all higher during the mirror condition, while tail-twining tended to decline during the mirror condition (P = 0.076). Hormones did not vary by experimental treatment, but were correlated with certain behaviors during the presentation of the mirror. While social behaviors changed with mirror exposure, self-directed and mirror-guided behaviors did not, indicating a lack of self-recognition. Use of a mirror was a safe and effective means of investigating mate-guarding behavior in response to a simulated intrusion, with the added benefit of not needing another animal to serve as an intruder; and thus may be of use in providing a laboratory model for natural behavior. Especially, as it eliminates the need for a stimulus animal, it would also be of possible use in investigating responses to a simulated intruder in wild populations of titis and other pithecines.
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Filippetti ML. What is special about our own face? Commentary: Tuning of temporo-occipital activity by frontal oscillations during virtual mirror exposure causes erroneous self-recognition. Front Psychol 2015; 6:1551. [PMID: 26528211 PMCID: PMC4603244 DOI: 10.3389/fpsyg.2015.01551] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2015] [Accepted: 09/24/2015] [Indexed: 11/13/2022] Open
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Zhang J, Ma K, Hommel B. The virtual hand illusion is moderated by context-induced spatial reference frames. Front Psychol 2015; 6:1659. [PMID: 26579042 PMCID: PMC4623196 DOI: 10.3389/fpsyg.2015.01659] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2015] [Accepted: 10/14/2015] [Indexed: 11/13/2022] Open
Abstract
The tendency to perceive an artificial effector as part of one’s own body is known to depend on temporal criteria, like the synchrony between stimulus events informing about the effector. The role of spatial factors is less well understood. Rather than physical distance, which has been manipulated in previous studies, we investigated the role of relative, context-induced distance between the participant’s real hand and an artificial hand stimulated synchronously or asynchronously with the real hand. We replicated previously reported distance effects in a virtual reality setup: the perception of ownership increased with decreased distance, and the impact of synchrony was stronger for short distances. More importantly, we found that ownership perception and impact of synchrony were affected by previous distance: the same, medium distance between real and artificial hand induced more pronounced ownership after having experienced a far-distance condition than after a near-distance condition. This suggests that subjective, context-induced spatial reference frames contribute to ownership perception, which does not seem to fit with the idea of fixed spatial criteria and/or permanent body representations as the sole determinants of perceived body ownership.
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Depression, Help-Seeking and Self-Recognition of Depression among Dominican, Ecuadorian and Colombian Immigrant Primary Care Patients in the Northeastern United States. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2015; 12:10450-74. [PMID: 26343691 PMCID: PMC4586621 DOI: 10.3390/ijerph120910450] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 08/07/2015] [Accepted: 08/19/2015] [Indexed: 12/31/2022]
Abstract
Latinos, the largest minority group in the United States, experience mental health disparities, which include decreased access to care, lower quality of care and diminished treatment engagement. The purpose of this cross-sectional study of 177 Latino immigrants in primary care is to identify demographic factors, attitudes and beliefs, such as stigma, perceived stress, and ethnic identity that are associated with depression, help-seeking and self-recognition of depression. Results indicated that 45 participants (25%) had depression by Patient Health Questionnaire (PHQ-9) criteria. Factors most likely to be associated with depression were: poverty; difficulty in functioning; greater somatic symptoms, perceived stress and stigma; number of chronic illnesses; and poor or fair self-rated mental health. Fifty-four people endorsed help-seeking. Factors associated with help-seeking were: female gender, difficulty in functioning, greater somatic symptoms, severity of depression, having someone else tell you that you have an emotional problem, and poor or fair self-rated mental health. Factors most likely to be associated with self-recognition were the same, but also included greater perceived stress. This manuscript contributes to the literature by examining attitudinal factors that may be associated with depression, help-seeking and self-recognition among subethnic groups of Latinos that are underrepresented in research studies.
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Garrett AM, Burgess RW. Self-awareness in the retina. eLife 2015; 4. [PMID: 26305501 PMCID: PMC4548409 DOI: 10.7554/elife.10233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Proteins called gamma-protocadherins are essential for the establishment of working circuits of neurons in the retina.
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Kostadinov D, Sanes JR. Protocadherin-dependent dendritic self-avoidance regulates neural connectivity and circuit function. eLife 2015; 4. [PMID: 26140686 PMCID: PMC4548410 DOI: 10.7554/elife.08964] [Citation(s) in RCA: 107] [Impact Index Per Article: 11.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2015] [Accepted: 07/02/2015] [Indexed: 12/30/2022] Open
Abstract
Dendritic and axonal arbors of many neuronal types exhibit self-avoidance, in which branches repel each other. In some cases, these neurites interact with those of neighboring neurons, a phenomenon called self/non-self discrimination. The functional roles of these processes remain unknown. In this study, we used retinal starburst amacrine cells (SACs), critical components of a direction-selective circuit, to address this issue. In SACs, both processes are mediated by the gamma-protocadherins (Pcdhgs), a family of 22 recognition molecules. We manipulated Pcdhg expression in SACs and recorded from them and their targets, direction-selective ganglion cells (DSGCs). SACs form autapses when self-avoidance is disrupted and fail to form connections with other SACs when self/non-self discrimination is perturbed. Pcdhgs are also required to prune connections between closely spaced SACs. These alterations degrade the direction selectivity of DSGCs. Thus, self-avoidance, self/non-self discrimination, and synapse elimination are essential for proper function of a circuit that computes directional motion. DOI:http://dx.doi.org/10.7554/eLife.08964.001 Nerve cells (or neurons) connect to one another to form circuits that control the animal's behavior. Typically, each neuron receives signals from other cells via branch-like structures called dendrites. Each specific type of neuron has a characteristic pattern of branched dendrites, which is different from the pattern of other types of neuron. Therefore, it is reasonable to imagine that the shape of these branches can influence how the neuron works; however, this idea has rarely been tested experimentally. Different processes are known to act together to control the pattern of the branched dendrites. For example, dendrites in some neurons avoid other dendrites from the same neuron. This phenomenon is referred to as ‘self-avoidance’. In some of these cases, the same dendrites freely interact with the dendrites of neighboring neurons of the same type; this is called ‘self/non-self discrimination’. It is not clear, however, how these two processes influence the activity of neural circuits. Both self-avoidance and self/non-self discrimination rely on the expression of genes that encode so-called recognition molecules. Kostadinov and Sanes have now altered the expression of these genes in mice to see the effect that disrupting these two phenomena has on a set of neurons called ‘starburst amacrine cells’ that are found at the back the eye. The dendrites of starburst amacrine cells generate signals when objects move across the animal's field of vision. These dendrites then signal to other starburst amacrine cells and to so-called ‘direction-selective ganglion cells’, which in turn send this information to the brain for further processing. The experiments revealed that these disruptions affected the connections between the dendrites. Starburst amacrine cells that lacked self-avoidance mistakenly formed connections with themselves—as if they mistook their own dendrites for those of other starburst cells. In contrast, neurons that lacked self/non-self discrimination made the opposite mistake, and rarely formed connections with each other—as if they mistook the dendrites of other starbursts for their own. Disruptions to either phenomenon interfered with the activity of the direction-selective ganglion cells. Following on from the work of Kostadinov and Sanes, the next challenges include uncovering how the recognition molecules help with self-avoidance and self/non-self discrimination. It will also be important to examine whether the conclusions based on one type of neurons can be generalized to others that also exhibit these two phenomena. DOI:http://dx.doi.org/10.7554/eLife.08964.002
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Pavani F, Galfano G. The multisensory body revealed through its cast shadows. Front Psychol 2015; 6:666. [PMID: 26042079 PMCID: PMC4436799 DOI: 10.3389/fpsyg.2015.00666] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 05/07/2015] [Indexed: 12/24/2022] Open
Abstract
One key issue when conceiving the body as a multisensory object is how the cognitive system integrates visible instances of the self and other bodies with one's own somatosensory processing, to achieve self-recognition and body ownership. Recent research has strongly suggested that shadows cast by our own body have a special status for cognitive processing, directing attention to the body in a fast and highly specific manner. The aim of the present article is to review the most recent scientific contributions addressing how body shadows affect both sensory/perceptual and attentional processes. The review examines three main points: (1) body shadows as a special window to investigate the construction of multisensory body perception; (2) experimental paradigms and related findings; (3) open questions and future trajectories. The reviewed literature suggests that shadows cast by one's own body promote binding between personal and extrapersonal space and elicit automatic orienting of attention toward the body-part casting the shadow. Future research should address whether the effects exerted by body shadows are similar to those observed when observers are exposed to other visual instances of their body. The results will further clarify the processes underlying the merging of vision and somatosensation when creating body representations.
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Mazzoleni S, Cartenì F, Bonanomi G, Senatore M, Termolino P, Giannino F, Incerti G, Rietkerk M, Lanzotti V, Chiusano ML. Inhibitory effects of extracellular self-DNA: a general biological process? THE NEW PHYTOLOGIST 2015; 206:127-132. [PMID: 25628124 DOI: 10.1111/nph.13306] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2014] [Accepted: 12/24/2014] [Indexed: 05/20/2023]
Abstract
Self-inhibition of growth has been observed in different organisms, but an underlying common mechanism has not been proposed so far. Recently, extracellular DNA (exDNA) has been reported as species-specific growth inhibitor in plants and proposed as an explanation of negative plant-soil feedback. In this work the effect of exDNA was tested on different species to assess the occurrence of such inhibition in organisms other than plants. Bioassays were performed on six species of different taxonomic groups, including bacteria, fungi, algae, plants, protozoa and insects. Treatments consisted in the addition to the growth substrate of conspecific and heterologous DNA at different concentration levels. Results showed that treatments with conspecific DNA always produced a concentration dependent growth inhibition, which instead was not observed in the case of heterologous DNA. Reported evidence suggests the generality of the observed phenomenon which opens new perspectives in the context of self-inhibition processes. Moreover, the existence of a general species-specific biological effect of exDNA raises interesting questions on its possible involvement in self-recognition mechanisms. Further investigation at molecular level will be required to unravel the specific functioning of the observed inhibitory effects.
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