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Dok obilje literature ukazuje na važnost psihijatrijskog probira zdravih dobrovoljaca koji sudjeluju u istraživanjima mentalnog zdravlja, ovo je prva studija kojom se detaljno istražuje uloga cjelovitoga liječničkog pregleda. Analizirani su rezultati medicinskog pregleda u 476 dobrovoljaca bez psihijatrijskih poremećaja i 64 dobrovoljaca s poremećajima anksioznosti kako bi se utvrdili učestalost i razlozi njihovog isključivanja iz studija. Svim dobrovoljcima uzeta je anamneza i napravljen fizikalni pregled, a kod 37 % dobrovoljaca učinjeni su laboratorijska obrada i EKG. Isključeno je 110 (20,4 %) dobrovoljaca, a stope isključenja bile su slične za zdrave dobrovoljce i dobrovoljce s anksioznim poremećajima. Pomoću fizikalnog pregleda, laboratorijskih pretraga te pregleda dostupne medicinske dokumentacije, tj. objektivnih metoda probira pronađeno je 55,1 % svih isključenja. Premda su ispitanici bili mladi i relativno zdravi, otkrivena su stanja koja mogu negativno utjecati na sigurnost dobrovoljaca i vrijednost znanstvenih rezultata (npr. teška hipertenzija, hepatitis C). Zahvaljujući objektivnim metodama probira, otkriveni su i psihijatrijski poremećaji (npr. poremećaji hranjenja, zloporaba droga), koje su dobrovoljci prikrili tijekom probira duševnog zdravlja. Iako je 20 % nalaza EKG-a očitano kao „promijenjen“ ili „graničan“, probir EKG-om nije otkrio značajne kardiološke poremećaje niti utjecao na podobnost za studije u ovom uzorku mladih dobrovoljaca. Otkriveno je da hiperkalijemija može biti uzrokovana poremećajem hranjenja, što predstavlja novu spoznaju o etiologiji hiperkalijemije i o elektrolitskim abnormalnostima zbog poremećaja hranjenja. Ovo istraživanje dokumentira komplementarnost medicinskog i psihijatrijskog probira te ukazuje na potrebu da se standardizira medicinski probir dobrovoljaca u psihijatrijskim istraživanjima., While previous reports demonstrate the importance of mental health screening of healthy volunteers in psychiatric research, this is the first study that specifically explores the role of medical screening. Findings on medical screening in 476 healthy volunteers and 64 volunteers with anxiety disorders were analyzed to determine rates and reasons for exclusion from studies. All subjects had history and physical examination and 37 % of participants completed laboratory assessment and ECG. One-hundred ten (20.4%) of volunteers were excluded. Exclusion rates were similar for healthy volunteers and patients. Out of all exclusions, 55.1 % were found by physical exam, laboratory testing and medical record review, i.e., objective methods of screening. Although the study population was young and relatively healthy, conditions were detected that could have a profound influence on the safety of participants and validity of research results (e.g., severe hypertension, hepatitis C). Owing to objective methods, medical screening also detected psychiatric disorders (e.g., eating disorders, drug abuse) that volunteers denied during the psychiatric screening. Although 20% of volunteers were labelled as having an abnormal or borderline ECG, screening ECGs did not detect significant cardiac pathology or affect eligibility for studies in this sample of young volunteers. It was discovered that hyperkalemia can be caused by an eating disorder, which represents a new finding about the etiology of hyperkalemia as well as a new finding about electrolyte abnormalities due to eating disorders. These findings demonstrate the complementary nature of medical and psychiatric evaluation and underscore the need to develop further standards in medical screening procedures in psychiatric research.

Significance Speech perception is improved when we are able to see the person who is speaking, but how visual speech cues are used to improve speech perception is currently unclear. Brain imaging has revealed that regions responsible for motor control are active during the perception of speech, opening up the possibility that visual cues are mapped onto an internal representation of the vocal tract. Here, we show that there is sufficient information in the configuration of the face to recover the vocal tract configuration and that the key areas responsible for driving the correspondence vary in accordance with the articulation required to form the acoustic signal at the appropriate point in a sentence., It is well established that speech perception is improved when we are able to see the speaker talking along with hearing their voice, especially when the speech is noisy. While we have a good understanding of where speech integration occurs in the brain, it is unclear how visual and auditory cues are combined to improve speech perception. One suggestion is that integration can occur as both visual and auditory cues arise from a common generator: the vocal tract. Here, we investigate whether facial and vocal tract movements are linked during speech production by comparing videos of the face and fast magnetic resonance (MR) image sequences of the vocal tract. The joint variation in the face and vocal tract was extracted using an application of principal components analysis (PCA), and we demonstrate that MR image sequences can be reconstructed with high fidelity using only the facial video and PCA. Reconstruction fidelity was significantly higher when images from the two sequences corresponded in time, and including implicit temporal information by combining contiguous frames also led to a significant increase in fidelity. A “Bubbles” technique was used to identify which areas of the face were important for recovering information about the vocal tract, and vice versa, on a frame-by-frame basis. Our data reveal that there is sufficient information in the face to recover vocal tract shape during speech. In addition, the facial and vocal tract regions that are important for reconstruction are those that are used to generate the acoustic speech signal.

Perceptual decisions entail the accumulation of sensory evidence for a particular choice towards an action plan. An influential framework holds that sensory cortical areas encode the instantaneous sensory evidence and downstream, action-related regions accumulate this evidence. The large-scale distribution of this computation across the cerebral cortex has remained largely elusive. Here, we develop a regionally-specific magnetoencephalography decoding approach to exhaustively map the dynamics of stimulus- and choice-specific signals across the human cortical surface during a visual decision. Comparison with the evidence accumulation dynamics inferred from behavior disentangles stimulus-dependent and endogenous components of choice-predictive activity across the visual cortical hierarchy. We find such an endogenous component in early visual cortex (including V1), which is expressed in a low (, Even decisions based on simple sensory stimuli result from an interplay between many brain regions. Here, the authors track the dynamics of information about sensory input and behavioral choice across the human cerebral cortex, uncovering feedback of decision signals to early sensory cortex.

Significance We revisit the concept of loss aversion by synthesizing distinct views into an integrative framework and by probing physiological biomarkers associated with the behavior. The framework decomposes loss aversion into a valuation bias, which weighs losses over gains, and a response bias, which avoids loss-related choices altogether. Further, we reveal a double dissociation in physiology underlying the decision process. Valuation bias was associated with preferential gaze allocation to losses whereas response bias was associated with pupillary dilation. Our framework exposes biological heterogeneity underlying loss aversion and distinguishes different loss-averse decision makers who are otherwise indistinguishable using conventional approaches. Our integrative approach provides a deeper analysis of the mechanisms underlying loss aversion and incorporates distinct views within a unified biological framework., Loss-averse decisions, in which one avoids losses at the expense of gains, are highly prevalent. However, the underlying mechanisms remain controversial. The prevailing account highlights a valuation bias that overweighs losses relative to gains, but an alternative view stresses a response bias to avoid choices involving potential losses. Here we couple a computational process model with eye-tracking and pupillometry to develop a physiologically grounded framework for the decision process leading to accepting or rejecting gambles with equal odds of winning and losing money. Overall, loss-averse decisions were accompanied by preferential gaze toward losses and increased pupil dilation for accepting gambles. Using our model, we found gaze allocation selectively indexed valuation bias, and pupil dilation selectively indexed response bias. Finally, we demonstrate that our computational model and physiological biomarkers can identify distinct types of loss-averse decision makers who would otherwise be indistinguishable using conventional approaches. Our study provides an integrative framework for the cognitive processes that drive loss-averse decisions and highlights the biological heterogeneity of loss aversion across individuals.

Our daily life is realized by the complex orchestrations of diverse brain functions, including perception, decision-making, and action. The essential goal of cognitive neuroscience is to reveal the complete representations underlying these functions. Recent studies have characterised perceptual experiences using encoding models. However, few attempts have been made to build a quantitative model describing the cortical organization of multiple active, cognitive processes. Here, we measure brain activity using fMRI, while subjects perform 103 cognitive tasks, and examine cortical representations with two voxel-wise encoding models. A sparse task-type model reveals a hierarchical organization of cognitive tasks, together with their representation in cognitive space and cortical mapping. A cognitive factor model utilizing continuous, metadata-based intermediate features predicts brain activity and decodes tasks, even under novel conditions. Collectively, our results show the usability of quantitative models of cognitive processes, thus providing a framework for the comprehensive cortical organization of human cognition., The authors construct quantitative models of human brain activity evoked by 103 cognitive tasks and reveal the organization of diverse cognitive functions in the brain. Their model, which uses latent cognitive features, predicts brain activity and decodes tasks, even under novel task conditions.

The human brain is inherently limited in the information it can make consciously accessible. When people monitor a rapid stream of visual items for two targets, they typically fail to see the second target if it occurs within 200–500 ms of the first, a phenomenon called the attentional blink (AB). The neural basis for the AB is poorly understood, partly because conventional neuroimaging techniques cannot resolve visual events displayed close together in time. Here we introduce an approach that characterises the precise effect of the AB on behaviour and neural activity. We employ multivariate encoding analyses to extract feature-selective information carried by randomly-oriented gratings. We show that feature selectivity is enhanced for correctly reported targets and suppressed when the same items are missed, whereas irrelevant distractor items are unaffected. The findings suggest that the AB involves both short- and long-range neural interactions between visual representations competing for access to consciousness., People often fail to perceive the second of two brief visual targets, a phenomenon known as the attentional blink (AB). Here the authors modelled behaviour and brain activity to show that the AB arises from short- and long-range interactions between representations of elementary visual features.

To what extent, if any, should minors have a say about whether they participate in research that offers them no prospect of direct benefit? This article addresses this question as it pertains to minors who cannot understand enough about what their participation would involve to make an autonomous choice, but can comprehend enough to have and express opinions about participating. The first aim is to defend David Wendler and Seema Shah’s claim that minors who meet this description should not be offered a choice about whether they participate. The second aim is to show, contra Wendler and Shah, that the principle of nonmaleficence requires more with respect to giving these minors a say than merely respecting their dissent. Additionally, it requires that investigators obtain affirmation of their non-dissent. This addresses intuitive concerns about denying children a choice, while steering clear of the problems that arise with allowing them one.

Significance Differential treatment of animate and inanimate objects often hinges on mind perception—the attribution of mental states to others. It has already been established that pictures of animate objects can elicit mind perception, albeit at reduced intensity. However, this loss of intensity is assumed to reflect an impoverishment of a rich stimulus, such as the projection of a living being into a static picture plane. The current study overturns this assumption by showing that “pure” abstraction can reduce mind perception independent of stimulus richness. Depicting things with minds raises ethical questions that have not been recognized previously. As these questions emerge from representational structure rather than representational content, they are unlikely to be quashed by improvements in image quality., Throughout our species history, humans have created pictures. The resulting picture record reveals an overwhelming preference for depicting things with minds. This preference suggests that pictures capture something of the mind that is significant to us, albeit at reduced potency. Here, we show that abstraction dims the perceived mind, even within the same picture. In a series of experiments, people were perceived as more real, and higher in both Agency (ability to do) and Experience (ability to feel), when they were presented as pictures than when they were presented as pictures of pictures. This pattern persisted across different tasks and even when comparators were matched for identity and image size. Viewers spontaneously discriminated between different levels of abstraction during eye tracking and were less willing to share money with a more abstracted person in a dictator game. Given that mind perception underpins moral judgement, our findings suggest that depicted persons will receive greater or lesser ethical consideration, depending on the level of abstraction.

Cortical body size representations are distorted in the adult, from low-level motor and sensory maps to higher levels multisensory and cognitive representations. Little is known about how such representations are built and evolve during infancy and childhood. Here we investigated how hand size is represented in typically developing children aged 6 to 10. Participants were asked to estimate their hand size using two different sensory modalities (visual or haptic). We found a distortion (underestimation) already present in the youngest children. Crucially, such distortion increases with age and regardless of the sensory modality used to access the representation. Finally, underestimation is specific for the body as no bias was found for object estimation. This study suggests that the brain does not keep up with the natural body growth. However, since motor behavior nor perception were impaired, the distortion seems functional and/or compensated for, for proper interaction with the external environment.

Learned rules help us accurately solve many problems, but by blindly following a strategy, we sometimes fail to find more efficient alternatives. Previous research found that humans are more susceptible to this “cognitive set” bias than other primates in a nonverbal computer task. We modified the task to test one hypothesis for this difference, that working memory influences the advantage of taking a shortcut. During training, 60 humans, 7 rhesus macaques, and 22 capuchin monkeys learned to select three icons in sequence. They then completed 96 baseline trials, in which only this learned rule could be used, and 96 probe trials, in which they could also immediately select the final icon. Rhesus and capuchin monkeys took this shortcut significantly more often than humans. Humans used the shortcut more in this new, easier task than in previous work, but started using it significantly later than the monkeys. Some participants of each species also used an intermediate strategy; they began the learned rule but switched to the shortcut after selecting the first item in the sequence. We suggest that these species differences arise from differences in rule encoding and in the relative efficiency of exploiting a familiar strategy versus exploring alternatives.

Divided attention is defined as focusing on different tasks at once, and this is described as one of the biggest problems of today's society. Default examinations for understanding attention are questionnaires or physiological signals, like evoked potentials and electroencephalography. Physiological records were obtained using visual, auditory, and auditory-visual stimuli combinations with 48 participants-18-25-year-old university students-to find differences between sustained and divided attention. A Fourier-based filter was used to get a 0.01-30-Hz frequency band. Fractal dimensions, entropy values, power spectral densities, and Hjorth parameters from electroencephalography and P300 components from evoked potentials were calculated as features. To decrease the size of the feature set, some features, which yield less detail level for data, were eliminated. The visual and auditory stimuli in selective attention were compared with the divided attention state, and the best accuracy was found to be 88.89% on a support vector machine with linear kernel. As a result, it was seen that divided attention could be more difficult to determine from selective attention, but successful classification could be obtained with appropriate methods. Contrary to literature, the study deals with the infrastructure of attention types by working on a completely healthy and attention-high group. Graphical abstract.

A common assumption is that good leaders are driven by a power motive that motivates them to influence others. However, leaders need to restrain themselves in social dilemmas where cooperation maximizes collective outcomes. We theorize that in social dilemmas, a desire for positive relationships (affiliation motive) is more beneficial than a power motive because it draws attention away from short-term self-interest towards understanding others. In a game of Settlers of Catan in the laboratory, we find that a functional variant of the affiliation motive relates to verbal encouragement of cooperation, to fewer occurrences of oil spills, to higher ratings of transformational leadership and, in a field survey, to fewer selfish business decisions. Furthermore, a dysfunctional variant of the power motive relates to two of three indicators of selfishness. Group members perceive selfish individuals as assuming leadership roles which indirectly relates to slightly higher ratings of transformational leadership. This pattern of evaluation may privilege men who, on average, show more selfish behaviour which can be partially attributed to their motives. Mere awareness of gender-based discrimination does not enable raters to circumvent this pattern of evaluation. This work suggests a need for interventions that increase appreciation of cooperative leaders.

When searching a target in a natural scene, it has been shown that both the target’s visual properties and similarity to the background influence whether and how fast humans are able to find it. So far, it was unclear whether searchers adjust the dynamics of their eye movements (e.g., fixation durations, saccade amplitudes) to the target they search for. In our experiment, participants searched natural scenes for six artificial targets with different spatial frequency content throughout eight consecutive sessions. High-spatial frequency targets led to smaller saccade amplitudes and shorter fixation durations than low-spatial frequency targets if target identity was known. If a saccade was programmed in the same direction as the previous saccade, fixation durations and successive saccade amplitudes were not influenced by target type. Visual saliency and empirical fixation density at the endpoints of saccades which maintain direction were comparatively low, indicating that these saccades were less selective. Our results suggest that searchers adjust their eye movement dynamics to the search target efficiently, since previous research has shown that low-spatial frequencies are visible farther into the periphery than high-spatial frequencies. We interpret the saccade direction specificity of our effects as an underlying separation into a default scanning mechanism and a selective, target-dependent mechanism.

This article describes oversight mechanisms for clinical research that have developed substantially over the last few decades, including institutional review boards and data safety and monitoring boards. LeRoy Walters and others in the 1970s in the US thoughtfully described the importance of fundamental ethical principles and the application of bioethics to clinical research. Dr. Walters's important essay and work with the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research helped identify and explain ethical principles that guide research. These principles, subsequently enunciated by the Commission in the Belmont Report, remain central to our understanding of the ethics of clinical research and are the foundation of our regulations. In this article, I review some history, successes, and challenges of IRBs and DSMBs to exemplify the significance of understanding and applying ethical principles to the design and conduct of clinical research, and to honor Dr. Walters's contributions.

Item does not contain fulltext Systemic inflammation plays a pivotal role in a multitude of conditions, including sepsis, trauma, major surgery and burns. However, comprehensive analysis of the pathophysiology underlying this systemic inflammatory response is greatly complicated by variations in the immune response observed in critically ill patients, which is a result of inter-individual differences in comorbidity, comedication, source of infection, causative pathogen, and onset of the inflammatory response. During experimental human endotoxemia, human subjects are challenged with purified endotoxin (lipopolysaccharide) intravenously which induces a short-lived, well-tolerated and controlled systemic inflammatory response, similar to that observed during sepsis. The human endotoxemia model can be conducted in a highly standardized and reproducible manner, using a carefully selected homogenous study population. As such, the experimental human endotoxemia model does not share the aforementioned clinical limitations and enables us to investigate both the mechanisms of systemic inflammation, as well as to evaluate novel (pharmacological) interventions in humans in vivo. The present review provides a detailed overview of the various designs, organ-specific changes, and strengths and limitations of the experimental human endotoxemia model, with the main focus on its use as a translational model for sepsis research.

Summary box Emerging evidence shows that the COVID-19 is mutating1; as of April 2021, COVID-19 mutations are identified in most of the countries worldwide.2 The scale and scope of these mutations could have a devastating effect on global pandemic control and vaccine development efforts.3 4 Furthering this perspective, the first mutation identified in the UK, the B.1.1.7 variant, is up to 70% more transmissible and 35% more deadly than the original coronavirus.5 6 As COVID-19 evolves its approaches to spread across communities of various backgrounds, we must also adapt and update our defensive methods promptly and adequately. In other words, to gain an in-depth and comprehensive understanding of COVID-19, such as its transmissibility and human–pathogen interaction, critical scientific evidence is needed. …

The obligate human pathogen Haemophilus ducreyi causes both cutaneous ulcers in children and sexually transmitted genital ulcers (chancroid) in adults. Pathogenesis is dependent on avoiding phagocytosis and exploiting the suppurative granuloma-like niche, which contains a myriad of innate immune cells and memory T cells. Despite this immune infiltrate, long-lived immune protection does not develop against repeated H. ducreyi infections—even with the same strain. Most of what we know about infectious skin diseases comes from naturally occurring infections and/or animal models; however, for H. ducreyi, this information comes from an experimental model of infection in human volunteers that was developed nearly three decades ago. The model mirrors the progression of natural disease and serves as a valuable tool to determine the composition of the immune cell infiltrate early in disease and to identify host and bacterial factors that are required for the establishment of infection and disease progression. Most recently, holistic investigation of the experimentally infected skin microenvironment using multiple “omics” techniques has revealed that non-canonical bacterial virulence factors, such as genes involved in central metabolism, may be relevant to disease progression. Thus, the immune system not only defends the host against H. ducreyi, but also dictates the nutrient availability for the invading bacteria, which must adapt their gene expression to exploit the inflammatory metabolic niche. These findings have broadened our view of the host-pathogen interaction network from considering only classical, effector-based virulence paradigms to include adaptations to the metabolic environment. How both host and bacterial factors interact to determine infection outcome is a current focus in the field. Here, we review what we have learned from experimental H. ducreyi infection about host-pathogen interactions, make comparisons to what is known for other skin pathogens, and discuss how novel technologies will deepen our understanding of this infection.

Controllability over stressors has major impacts on brain and behavior. In humans, however, the effect of controllability on responses to stressors is poorly understood. Using functional magnetic resonance imaging (fMRI), we investigated how controllability altered responses to a shock-plus-sound stressor with a between-group yoked design, where participants in controllable and uncontrollable groups experienced matched stressor exposure. Employing Bayesian multilevel analysis at the level of regions of interest and voxels in the insula, and standard voxelwise analysis, we found that controllability decreased stressor-related responses across threat-related regions, notably in the bed nucleus of the stria terminalis and anterior insula. Posterior cingulate cortex, posterior insula, and possibly medial frontal gyrus showed increased responses during control over stressor. Our findings support the idea that the aversiveness of stressors is reduced when controllable, leading to decreased responses across key regions involved in anxiety-related processing, even at the level of the extended amygdala., Limbachia et al conduct a fMRI study in which participants are shown stressful stimuli that is either controllable or not. They show that the ability to control a stressor results in reduced activity in key areas of the brain that coordinate responses to a perceived threat.

Visual short-term memory (VSTM) enables humans to form a stable and coherent representation of the external world. However, the nature and temporal dynamics of the neural representations in VSTM that support this stability are barely understood. Here we combined human intracranial electroencephalography (iEEG) recordings with analyses using deep neural networks and semantic models to probe the representational format and temporal dynamics of information in VSTM. We found clear evidence that VSTM maintenance occurred in two distinct representational formats which originated from different encoding periods. The first format derived from an early encoding period (250 to 770 ms) corresponded to higher-order visual representations. The second format originated from a late encoding period (1,000 to 1,980 ms) and contained abstract semantic representations. These representational formats were overall stable during maintenance, with no consistent transformation across time. Nevertheless, maintenance of both representational formats showed substantial arrhythmic fluctuations, i.e., waxing and waning in irregular intervals. The increases of the maintained representational formats were specific to the phases of hippocampal low-frequency activity. Our results demonstrate that human VSTM simultaneously maintains representations at different levels of processing, from higher-order visual information to abstract semantic representations, which are stably maintained via coupling to hippocampal low-frequency activity.

The role of isochrony in speech—the hypothetical division of speech units into equal duration intervals—has been the subject of a long-standing debate. Current approaches in neurosciences have brought new perspectives in that debate through the theoretical framework of predictive coding and cortical oscillations. Here we assess the comparative roles of naturalness and isochrony in the intelligibility of speech in noise for French and English, two languages representative of two well-established contrastive rhythm classes. We show that both top-down predictions associated with the natural timing of speech and to a lesser extent bottom-up predictions associated with isochrony at a syllabic timescale improve intelligibility. We found a similar pattern of results for both languages, suggesting that temporal characterisation of speech from different rhythm classes could be unified around a single core speech unit, with neurophysiologically defined duration and linguistically anchored temporal location. Taken together, our results suggest that isochrony does not seem to be a main dimension of speech processing, but may be a consequence of neurobiological processing constraints, manifesting in behavioural performance and ultimately explaining why isochronous stimuli occupy a particular status in speech and human perception in general.

Social media users face a tension between presenting themselves in an idealized or authentic way. Here, we explore how prioritizing one over the other impacts users’ well-being. We estimate the degree of self-idealized vs. authentic self-expression as the proximity between a user’s self-reported personality and the automated personality judgements made on the basis Facebook Likes and status updates. Analyzing data of 10,560 Facebook users, we find that individuals who are more authentic in their self-expression also report greater Life Satisfaction. This effect appears consistent across different personality profiles, countering the proposition that individuals with socially desirable personalities benefit from authentic self-expression more than others. We extend this finding in a pre-registered, longitudinal experiment, demonstrating the causal relationship between authentic posting and positive affect and mood on a within-person level. Our findings suggest that the extent to which social media use is related to well-being depends on how individuals use it., It is often tempting for social media users to present themselves in an idealized way. Here, based on analyses of a large set of Facebook profiles together with a longitudinal experiment, the authors find evidence that more authentic self-expression may be psychologically beneficial, as it is related to greater well-being.

Event-related synchronisation (ERS) and event-related desynchronisation (ERD) have been observed via magnetoencephalography (MEG) in the language-dominant hemisphere. However, the relationship between ERS/ERD and clinical language indices is unclear. Therefore, the present study evaluated brain activity utilising MEG during a verb generation task in 36 subjects and determined ERS/ERD power values in θ, α, β, low γ and high γ frequency bands. To measure clinical language indices, we adopted Wechsler Memory Scale-revised. We observed ERD in the α band from the bilateral occipital to the left central brain region, in the β band from the bilateral occipital to the left frontal region and in the low γ band a high-power signal in the left frontal region. We also observed ERS in the θ band in bilateral frontal region and in the high γ band in bilateral occipital region. Furthermore, we found a significant negative correlation between α-band ERD power at the left postcentral gyrus and medial superior frontal gyrus and verbal memory score (correlation coefficients = − 0.574 and − 0.597, respectively). These results suggest that individuals with lower linguistic memory have less desynchronised α-band ERD power and α-band ERD power in the left hemisphere may be a neurophysiological biomarker for verbal memory.

International audience; Efforts to exclude past experiences from conscious awareness can lead to forgetting. Memory suppression is central to affective disorders, but we still do not really know whether emotions, including their physiological causes, are also impacted by this process in normal functioning individuals. In two studies, we measured the after-effects of suppressing negative memories on cardiac response in healthy participants. Results of Study 1 revealed that efficient control of memories was associated with long-term inhibition of the cardiac deceleration that is normally induced by disgusting stimuli. Attempts to suppress sad memories, by contrast, aggravated the cardiac response, an effect that was closely related to the inability to forget this specific material. In Study 2, electroencephalography revealed a reduction in power in the theta (3-8 Hz), alpha (8-12 Hz) and low-beta (13-20 Hz) bands during the suppression of unwanted memories, compared with their voluntary recall. Interestingly, however, the reduction of power in the theta frequency band during memory control was related to a subsequent inhibition of the cardiac response. These results provide a neurophysiological basis for the influence of memory control mechanisms on the cardiac system, opening up new avenues and questions for treating intrusive memories using motivated forgetting.

Significance Under what conditions do groups outperform their individual members? This question is of paramount importance and has spurred many studies in management and organizational science, psychology, sociology, complex systems, and computer science. Here, we investigate the conditions under which the interaction network within a group can adapt to leverage the dispersion of individual abilities and promote collective intelligence. We find that network plasticity and feedback provide fundamental mechanisms for both improving individual judgments and inducing the collective “wisdom of the network,” allowing groups to outperform their best individuals working in isolation., Social networks continuously change as new ties are created and existing ones fade. It is widely acknowledged that our social embedding has a substantial impact on what information we receive and how we form beliefs and make decisions. However, most empirical studies on the role of social networks in collective intelligence have overlooked the dynamic nature of social networks and its role in fostering adaptive collective intelligence. Therefore, little is known about how groups of individuals dynamically modify their local connections and, accordingly, the topology of the network of interactions to respond to changing environmental conditions. In this paper, we address this question through a series of behavioral experiments and supporting simulations. Our results reveal that, in the presence of plasticity and feedback, social networks can adapt to biased and changing information environments and produce collective estimates that are more accurate than their best-performing member. To explain these results, we explore two mechanisms: 1) a global-adaptation mechanism where the structural connectivity of the network itself changes such that it amplifies the estimates of high-performing members within the group (i.e., the network “edges” encode the computation); and 2) a local-adaptation mechanism where accurate individuals are more resistant to social influence (i.e., adjustments to the attributes of the “node” in the network); therefore, their initial belief is disproportionately weighted in the collective estimate. Our findings substantiate the role of social-network plasticity and feedback as key adaptive mechanisms for refining individual and collective judgments.

The Concealed Information Test (CIT) enables the detection of certain (e.g., crime-relevant or personal) information, even if participants aim to conceal their knowledge. The current preregistered study investigated whether previously observed impairing effects of alcohol intoxication on participants’ performance in a reaction time CIT (RT CIT) field study also translate to a laboratory environment. In contrast to the previous study of Suchotzki and Gamer (Sci Rep 8:7825, 2018) in which alcohol consumption was voluntary and self-administered, the current study used a randomized assignment of participants to either an alcohol group (n = 88; receiving a drink with 3 cl alcohol) or a sober control group (n = 89; receiving a drink with just some alcohol drops to hide group assignment). After drink administration, participants completed an RT CIT, in which they were instructed to hide knowledge of their own identity. Blood alcohol concentration (BAC) was estimated via breath alcohol ratio. In contrast to the previous field study, results revealed no differences in CIT-performance between intoxicated and sober participants. Aside from questioning the robustness of the result of the previous field study, our results also point to a number of interesting theoretical explanations for the discrepancy between both results, which are elaborated in the discussion.

Neural speech decoding-driven brain-computer interface (BCI) or speech-BCI is a novel paradigm for exploring communication restoration for locked-in (fully paralyzed but aware) patients. Speech-BCIs aim to map a direct transformation from neural signals to text or speech, which has the potential for a higher communication rate than the current BCIs. Although recent progress has demonstrated the potential of speech-BCIs from either invasive or non-invasive neural signals, the majority of the systems developed so far still assume knowing the onset and offset of the speech utterances within the continuous neural recordings. This lack of real-time voice/speech activity detection (VAD) is a current obstacle for future applications of neural speech decoding wherein BCI users can have a continuous conversation with other speakers. To address this issue, in this study, we attempted to automatically detect the voice/speech activity directly from the neural signals recorded using magnetoencephalography (MEG). First, we classified the whole segments of pre-speech, speech, and post-speech in the neural signals using a support vector machine (SVM). Second, for continuous prediction, we used a long short-term memory-recurrent neural network (LSTM-RNN) to efficiently decode the voice activity at each time point via its sequential pattern-learning mechanism. Experimental results demonstrated the possibility of real-time VAD directly from the non-invasive neural signals with about 88% accuracy.

Multivariate Pattern Analysis (MVPA) has grown in importance due to its capacity to use both coarse and fine scale patterns of brain activity. However, a major limitation of multivariate analysis is the difficulty of aligning features across brains, which makes MVPA a subject specific analysis. Recent work by Haxby et al. (2011) introduced a method called Hyperalignment that explored neural activity in ventral temporal cortex during object recognition and demonstrated the ability to align individual patterns of brain activity into a common high dimensional space to facilitate Between Subject Classification (BSC). Here we examined BSC based on Hyperalignment of motor cortex during a task of motor imagery of three natural actions (lift, knock and throw). To achieve this we collected brain activity during the combined tasks of action observation and motor imagery to a parametric action space containing 25 stick-figure blends of the three natural actions. From these responses we derived Hyperalignment transformation parameters that were used to map subjects’ representational spaces of the motor imagery task in the motor cortex into a common model representational space. Results showed that BSC of the neural response patterns based on Hyperalignment exceeded both BSC based on anatomical alignment as well as a standard Within Subject Classification (WSC) approach. We also found that results were sensitive to the order in which participants entered the Hyperalignment algorithm. These results demonstrate the effectiveness of Hyperalignment to align neural responses across subject in motor cortex to enable BSC of motor imagery.

Representing visibly present stimuli is as limited in capacity as representing invisible stimuli in visual working memory (WM). In this study, we explored whether concurrently representing stimuli within view affects representing objects in visual WM, and if so, whether this effect is modulated by the storage states (active and silent state) of memory contents? In experiment 1, participants were asked to perform the change-detect task in a simultaneous-representing condition in which WM content and the continuously-visible stimuli in view were simultaneously represented, as well as a baseline condition in which only the representations of visual WM content were maintained. The results showed that the representations in visual WM would be impaired when the continuously-visible stimuli in view were concurrently represented, revealed by the reduced CDA amplitude and the lower behavior performance. In experiment 2, a dual-serial retro-cue paradigm was adopted to guide participants to maintain memory items in two different storage states, and the results revealed that simultaneously representing the continuously-visible stimuli and the WM content would only impair the WM representations in the active state. These evidences demonstrated that only the visual WM representations that were maintained in the active state would definitely share the limited resources with the representations of continuously-visible information, and further supported the dissociation between the active state and silent state of visual WM storage.

Eyeblink conditioning, finger tapping, and prism adaptation are three tasks that have been linked to the cerebellum. Previous research suggests that these tasks recruit distinct but partially overlapping parts of the cerebellum, as well as different extra-cerebellar networks. However, the relationships between the performances on these tasks remain unclear. Here we tested eyeblink conditioning, finger tapping, and prism adaptation in 42 children and 44 adults and estimated the degree of correlation between the performance measures. The results show that performance on all three tasks improves with age in typically developing school-aged children. However, the correlations between the performance measures of the different tasks were consistently weak and without any consistent directions. This reinforces the view that eyeblink conditioning, finger tapping, and prism adaptation rely on distinct mechanisms. Consequently, performance on these tasks cannot be used separately to assess a common cerebellar function or to make general conclusions about cerebellar dysfunction. However, together, these three behavioral tasks have the potential to contribute to a nuanced picture of human cerebellar functions during development.

Funder: RCUK | Medical Research Council (MRC); doi: https://doi.org/10.13039/501100000265, Human visual cortex contains discrete areas that respond selectively to specific object categories such as faces, bodies, and places. A long-standing question is whether these areas are shaped by genetic or environmental factors. To address this question, here we analyzed functional MRI data from an unprecedented number (n = 424) of monozygotic (MZ) and dizygotic (DZ) twins. Category-selective maps were more identical in MZ than DZ twins. Within each category-selective area, distinct subregions showed significant genetic influence. Structural MRI analysis revealed that the ‘genetic voxels’ were predominantly located in regions with higher cortical curvature (gyral crowns in face areas and sulcal fundi in place areas). Moreover, we found that cortex was thicker and more myelinated in genetic voxels of face areas, while it was thinner and less myelinated in genetic voxels of place areas. This double dissociation suggests a differential development of face and place areas in cerebral cortex.

Acute physical exercise improves memory functions by increasing neural plasticity in the hippocampus. In animals, a single session of physical exercise has been shown to boost anandamide (AEA), an endocannabinoid known to promote hippocampal plasticity. Hippocampal neuronal networks encode episodic memory representations, including the temporal organization of elements, and can thus benefit motor sequence learning. While previous work established that acute physical exercise has positive effects on declarative memory linked to hippocampal plasticity mechanisms, its influence on memory for motor sequences, and especially on neural mechanisms underlying possible effects, has been less investigated.Here we studied the impact of acute physical exercise on motor sequence learning, and its underlying neurophysiological mechanisms in humans, using a cross-over randomized within-subjects design. We measured behavior, fMRI activity, and circulating AEA levels in fifteen healthy participants while they performed a serial reaction time task (SRTT) before and after a short period of exercise (moderate or high intensity) or rest.We show that exercise enhanced motor sequence memory, significantly for high intensity exercise and tending towards significance for moderate intensity exercise. This enhancement correlated with AEA increase, and dovetailed with local increases in caudate nucleus and hippocampus activity.These findings demonstrate that acute physical exercise promotes sequence learning, thus attesting the overarching benefit of exercise to hippocampus-related memory functions.

Working memory (WM) is important to maintain information over short time periods to provide some stability in a constantly changing environment. However, brain activity is inherently dynamic, raising a challenge for maintaining stable mental states. To investigate the relationship between WM stability and neural dynamics, we used electroencephalography to measure the neural response to impulse stimuli during a WM delay. Multivariate pattern analysis revealed representations were both stable and dynamic: there was a clear difference in neural states between time-specific impulse responses, reflecting dynamic changes, yet the coding scheme for memorised orientations was stable. This suggests that a stable subcomponent in WM enables stable maintenance within a dynamic system. A stable coding scheme simplifies readout for WM-guided behaviour, whereas the low-dimensional dynamic component could provide additional temporal information. Despite having a stable subspace, WM is clearly not perfect—memory performance still degrades over time. Indeed, we find that even within the stable coding scheme, memories drift during maintenance. When averaged across trials, such drift contributes to the width of the error distribution., Working memory degrades over time. This study suggests that the neural coding scheme is stable, despite other time-varying dynamics. Error in performance is likely due to drift in the mnemonic representation within the otherwise stable coding scheme.

Virtual reality (VR) is a potentially challenging social environment for effective communication and collaboration. Thus, we conducted a VR study to determine whether increased familiarity with a teammate would improve performance on a joint decision making task. Specifically, because attitude familiarity, or knowledge of another person’s attitudes, has been correlated with better relationship functioning in the past, we anticipated that team performance would improve when teammates were first asked to discuss their task-relevant attitudes with one another. We also hypothesized that increased familiarity would be particularly useful in immersive VR, where typical social and other nonverbal cues were lacking. Twenty pairs recruited from a workplace environment were randomly assigned to either the Familiar or Control condition before completing a joint decision making task both in VR and on desktop monitors. The manipulation of attitude familiarity was successful: pairs in the Familiar condition were significantly more aware of their partners’ unique task-relevant attitudes. Results found that in VR, Familiar pairs were more accurate at determining patterns to events. Additionally, for teams less experienced in VR, Familiar pairs were also more accurate at predicting future events. However, there was no meaningful statistical difference in pairs’ ability to identify information. Familiar teams also took more time to answer questions, and we found no difference in self-reported communication quality. Overall, this was the first successful manipulation of attitude familiarity and results indicate that such an intervention may prove useful in a collaborative work environment, as Familiar teams demonstrated greater accuracy, especially in VR.

All species face the important adaptive problem of efficiently locating high-quality nutritional resources. We explored whether human spatial cognition is enhanced for high-calorie foods, in a large multisensory experiment that covertly tested the location memory of people who navigated a maze-like food setting. We found that individuals incidentally learned and more accurately recalled locations of high-calorie foods – regardless of explicit hedonic valuations or personal familiarity with foods. In addition, the high-calorie bias in human spatial memory already became evident within a limited sensory environment, where solely odor information was available. These results suggest that human minds continue to house a cognitive system optimized for energy-efficient foraging within erratic food habitats of the past, and highlight the often underestimated capabilities of the human olfactory sense.

Moment arm-angle functions (MA-a-functions) are commonly used to estimate in vivo muscle forces in humans. However, different MA-a-functions might not only influence the magnitude of the estimated muscle forces but also change the shape of the muscle’s estimated force-angle relationship (F-a-r). Therefore, we investigated the influence of different literature based Achilles tendon MA-a-functions on the triceps surae muscle-tendon unit F-a-r. The individual in vivo triceps torque-angle relationship was determined in 14 participants performing maximum voluntary fixed-end plantarflexion contractions from 18.3° ± 3.2° plantarflexion to 24.2° ± 5.1° dorsiflexion on a dynamometer. The resulting F-a-r were calculated using 15 literature-based in vivo Achilles tendon MA-a-functions. MA-a-functions affected the F-a-r shape and magnitude of estimated peak active triceps muscle-tendon unit force. Depending on the MA-a-function used, the triceps was solely operating on the ascending limb (n = 2), on the ascending limb and plateau region (n = 12), or on the ascending limb, plateau region and descending limb of the F-a-r (n = 1). According to our findings, the estimated triceps muscle–tendon unit forces and the shape of the F-a-r are highly dependent on the MA-a-function used. As these functions are affected by many variables, we recommend using individual Achilles tendon MA-a-functions, ideally accounting for contraction intensity-related changes in moment arm magnitude., Deutsche Forschungsgemeinschaft, Projekt DEAL

The large number of behavioral studies testing whether working memory training improves performance on an untrained task have yielded inconclusive results. Moreover, some studies have investigated the possible neural changes during the performance of untrained tasks after training. Here, we studied the transfer from n-back training to the Paced Auditory Serial Addition Test (PASAT), two different tasks that use the central executive system to maintain verbal stimuli. Participants completed fMRI sessions at baseline, immediately after one week of training, and at the five-week follow-up. Although behavioral transfer effects were not obtained, training was associated with decreased activation in the anterior dorsolateral prefrontal cortex (DLPFC; BA 9/46) while performing the PASAT that remained stable five weeks later. Consistent with our hypothesis, the changes in the anterior DLFPC largely overlapped with the n-back task fMRI activations. In conclusion, working memory training improves efficiency in brain areas involved in the trained task that may affect untrained tasks, specifically in brain areas responsible for the same cognitive processes.

International audience; From year-to-year, environment is becoming one of the major concerns of human societies. Few studies have investigated the biological processes involved in environmental scene perception. Here, we initiate a line of research by beginning to study emotional processes involved in this perception. Our results demonstrate a clear distinction between "Clean" and "Polluted" environments according to the pleasure and approach desire ratings they induced. Moreover, women expressed higher pleasure in the "Clean" condition, as did older participants. Finally, rural scenes induced higher pleasure in participants than urban ones.

We show that the human voice has complex acoustic qualities that are directly coupled to peripheral musculoskeletal tensioning of the body, such as subtle wrist movements. In this study, human vocalizers produced a steady-state vocalization while rhythmically moving the wrist or the arm at different tempos. Although listeners could only hear and not see the vocalizer, they were able to completely synchronize their own rhythmic wrist or arm movement with the movement of the vocalizer which they perceived in the voice acoustics. This study corroborates recent evidence suggesting that the human voice is constrained by bodily tensioning affecting the respiratory-vocal system. The current results show that the human voice contains a bodily imprint that is directly informative for the interpersonal perception of another's dynamic physical states.

Self-esteem refers to the extent to which we feel positive or negative about ourselves, and reflects an individual’s subjective evaluation of personal worth and attitudes about the self. As one kind of positive psychosocial resources, high self-esteem has been found to buffer the effects of stress on physical health. However, little is known about the possible neural basis underlying the association between physical health and self-esteem. In the present study, we investigated whether the hippocampus served as a neuroanatomical basis for the association between self-esteem and physical health in a large population of healthy young adults. We examined self-esteem and self-reported physical health with the Rosenberg Self Esteem Scale (RSES) and the Chinese Constitution Questionnaire (CCQ) respectively, and gray matter volume of the hippocampus was measured using magnetic resonance imaging. As expected, we found that individuals with higher levels of self-esteem had better self-reported physical health. Importantly, the mediation analysis showed that the gray matter volume of the hippocampus mediated the link between self-esteem and physical health, suggesting its critical role in the neural circuitry through which self-esteem is related to physical health.

It was recently proposed that olfaction evolved to aid navigation. Consistent with this hypothesis, olfactory identification and spatial memory are linked to overlapping brain areas which include the orbitofrontal cortex and hippocampus. However, the relationship between these two processes has never been specifically investigated. Here, we show that olfactory identification covaries with spatial memory in humans. We also found that the cortical thickness of the left medial orbitofrontal cortex, and the volume of the right hippocampus, predict both olfactory identification and spatial memory. Finally, we demonstrate deficits in both olfactory identification and spatial memory in patients with lesions of the medial orbitofrontal cortex. Our findings reveal an intrinsic relationship between olfaction and spatial memory that is supported by a shared reliance on the hippocampus and medial orbitofrontal cortex. This relationship may find its roots in the parallel evolution of the olfactory and hippocampal systems., Olfaction, the sense of smell, may have originally evolved to aid navigation in space, but there is no direct evidence of a link between olfaction and navigation in humans. Here the authors show that olfaction and spatial memory abilities are correlated and rely on similar brain regions in humans.

Background Mixed frequency and phase coding (FPC) can achieve the significant increase of the number of commands in steady-state visual evoked potential-based brain-computer interface (SSVEP-BCI). However, the inconsistent phases of the SSVEP over channels in a trial and the existence of non-contributing channels due to noise effects can decrease accurate detection of stimulus frequency. New method We propose a novel command detection method based on a complex sparse spatial filter (CSSF) by solving l1- and l2,1-regularization problems for a mixed-coded SSVEP-BCI. In particular, l2,1-regularization (aka group sparsification) can lead to the rejection of electrodes that are not contributing to the SSVEP detection. Results A calibration data based canonical correlation analysis (CCA) and CSSF with l1- and l2,1-regularization cases were demonstrated for a 16-target stimuli with eleven subjects. The results of statistical test suggest that the proposed method with l1- and l2,1-regularization significantly achieved the highest ITR. Comparison with existing methods The proposed approaches do not need any reference signals, automatically select prominent channels, and reduce the computational cost compared to the other mixed frequency-phase coding (FPC)-based BCIs. Conclusions The experimental results suggested that the proposed method can be usable implementing BCI effectively with reduce visual fatigue.

Both reasoning ability and social learning play a crucial role in human adaptation. Cognitive abilities like enhanced reasoning skills have combined with cumulative cultural adaptation to allow our species to dominate the world like no other. Thus, understanding how social learning interacts with individual reasoning ability is crucial for unravelling our evolutionary history. Here we describe a laboratory experiment designed to investigate the effect of social learning on individuals’ ability to infer a general rule about unfamiliar problems. In this experiment, social information had both positive and negative effects on individuals’ likelihood of inferring the rule. Social learners required more evidence to infer the rule than did individual learners, suggesting that social learning inhibits cognitive effort but social learning provided individuals with information that individual learners were unlikely to gather on their own, especially as the task became more difficult. When individuals are unlikely to discover useful information by themselves, social learning can potentiate understanding even though it reduces individual cognitive effort.