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The information available through our senses is noisy, incomplete, and to varying degrees ambiguous. The perceptual system must create stable and reliable percepts out of this restricted information. It solves this perceptual inference problem by integrating memories of previous percepts and making predictions about the perceptual future. Using ambiguous figures and a new experimental approach, we studied whether generating predictions based on regularities in the past affects processing of the present and how this is done. Event-related potentials (ERPs) were measured to investigate whether a highly regular temporal context of either ambiguous or unambiguous stimulus variants differently affects processing of a current stimulus and/or task execution. Further, we tested whether symbolic announcements about the immediate perceptual future can replace the past experience of regularities as a source for making predictions. Both ERP and reaction time varied as a function of stimulus ambiguity in the temporal context of a present stimulus. No such effects were found with symbolic announcements. Our results indicate that predictions about the future automatically alter processing of the present, even if the predictions are irrelevant for the present percept and task. However, direct experiences of past regularities are necessary for predicting the future whereas symbolic information about the future is not sufficient.

The information available through our senses is noisy, incomplete, and ambiguous. Our perceptual systems have to resolve this ambiguity to construct stable and reliable percepts. Previous EEG studies found large amplitude differences in two event-related potential (ERP) components 200 and 400 ms after stimulus onset when comparing ambiguous with disambiguated visual information ("ERP Ambiguity Effects"). These effects so far generalized across classical ambiguous figures from different visual categories at lower (geometry, motion) and intermediate (Gestalt perception) levels. The present study aimed to examine whether these ERP Effects are restricted to ambiguous figures or whether they also occur for different degrees of visibility. Smiley faces with low and high visibility of emotional expressions, as well as abstract figures with low and high visibility of a target curvature were presented. We thus compared ambiguity effects in geometric cube stimuli with visibility in emotional faces, and with visibility in abstract figures. ERP Effects were replicated for the geometric stimuli and very similar ERP Effects were found for stimuli with emotional face expressions but also for abstract figures. Conclusively, the ERP amplitude effects generalize across fundamentally different stimulus categories and show highly similar effects for different degrees of stimulus ambiguity and stimulus visibility. We postulate the existence of a high-level/meta-perceptual evaluation instance, beyond sensory details, that estimates the certainty of a perceptual decision. The ERP Effects may reflect differences in evaluation results.

The flow state is defined by intense involvement in an activity with high degrees of concentration and focused attention accompanied by a sense of pleasure. Video games are effective tools for inducing flow, and keeping players in this state is considered to be one of the central goals of game design. Many studies have focused on the underlying physiological and neural mechanisms of flow. Results are inconsistent when describing a unified mechanism underlying this mental state. This paper provides a comprehensive review of the physiological and neural correlates of flow and explains the relationship between the reported physiological and neural markers of the flow experience. Despite the heterogeneous results, it seems possible to establish associations between reported markers and the cognitive and experiential aspects of flow, particularly regarding arousal, attention control, reward processing, automaticity, and self-referential processing.

Abstract: The physiological and psychological underpinnings of near-death experiences (NDEs) are not yet understood. In this article, we show that for "critical" NDEs reported after cardiac arrest, two different neurophysiological models have been proposed that, in the literature so far, have not been adequately distinguished from each other. In the real-time model, it is postulated that during critical NDEs, residual activities in the cerebrum were sufficient to generate NDEs in real time. In the reconstruction model, it is assumed that due to severe oxygen deficiency, critical NDEs could not have occurred at the time in question but were reconstructed later during the regeneration phase of the brain. To assess the plausibility of these two models, we analyzed the phenomenology of the view of one's own body from above (autoscopy) that frequently occurs in the beginnings of NDEs. In addition to the available literature, we used original descriptions of autoscopies obtained in an online survey conducted in 2015. We found that the reconstruction model is not supported by empirical findings and that some findings even speak against it. We therefore conclude that future discussions of explanatory models of NDEs should focus primarily on the neurophysiological real-time model and a third alternative according to which autoscopies and NDEs occur in relative independence from the prevailing neurophysiological processes in the brain.

Research on the perception of silence has led to insights regarding its positive effects on individuals. We conducted a series of studies during which individuals were exposed to several minutes of silence in different contexts. Participants were introduced to different social and environmental settings, either in a seminar room at a university or in a city garden, alone or in a group. Instructions across studies varied, as participants were exposed to real waiting situations, were asked to just think and to explicitly experience the time interval without further instructions or following a session of Depth Relaxation Music Therapy (DRMT)/Hypnomusictherapy (HMT). Silence was judged to significantly increase relaxation, improve mood states, and alter the perception of time and the orientation toward the present moment. We controlled for influences of trait variables, such as impulsivity, mindfulness, daydreaming, and time perspective. Findings empirically demonstrate that exposure to silence can be effective in therapeutic and educational contexts to promote relaxation and well-being.

A popular model for sensory processing, known as predictive coding, proposes that incoming signals are iteratively compared with top-down predictions along a hierarchical processing scheme. At each step, error signals arising from differences between actual input and prediction are forwarded and recurrently minimized by updating internal models to finally be "explained away". However, the neuronal mechanisms underlying such computations and their limitations in processing speed are largely unknown. Further, it remains unclear at which step of cortical processing prediction errors are explained away, if at all. In the present study, human subjects briefly viewed the superposition of two orthogonally oriented gratings followed by abrupt removal of one orientation after either 33 or 200 milliseconds. Instead of strictly seeing the remaining orientation, observers report rarely but highly significantly an illusory percept of the arithmetic difference between previous and actual orientations. Previous findings in cats using the identical paradigm suggest that such difference signals are inherited from first steps of visual cortical processing. In light of early modeling accounts of predictive coding, in which visual neurons were interpreted as residual error detectors signaling the difference between actual input and its temporal prediction based on past input, our data may indicate continued access to residual errors. Such strategy permits time-critical perceptual decision making across a spectrum of competing internal signals up to the highest levels of processing. Thus, the occasional appearance of a prediction error-like illusory percept may uncover maintained flexibility at perceptual decision stages when subjects cope with highly dynamic and ambiguous visual stimuli.

Addictive disorders are characterized by impulsive behavior that leads to difficulties in preventing certain behaviors despite negative consequences. This symptom predisposes to a vulnerability in developing addictive disorders and is also aggravated by the addiction process itself. As such, understanding the underlying mechanisms of impulsivity is a challenge for understanding the pathophysiology of addiction. One common link between impulsivity and addiction is that both involve actions and decisions that are realized faster than they should be in time. Impulsive traits increase the tendency to choose immediate gratification instead of delayed gratification even when preferred. This observation suggests a relationship between impulsivity and time processing. To better understand this relationship, we reviewed the literature that describes the relationship between time processing and impulsivity in addictive disorders in humans. Despite a lack of literature concerning this question in alcohol, cannabis and gambling disorders, we highlight that addictive behaviors are a good model for understanding the pathophysiology of impulsivity, and could help us to better understand the relationship between time perception and impulsivity.

BACKGROUND: Distant intention research refers to experiments in which a distant interaction between two persons is assessed that precludes conventional communication. In these experiments the intention of one person is varied systematically while the effect of this variation is assessed in the remote other person. AIMS: Our study aimed at improving effect sizes by participant selection based on a screening test and by including experienced meditators. METHOD: 66 participants with meditation experience participated in a forced-choice psi-test as a screening test. Participants with similar performance were invited as pairs for a distant intention experiment. The task of the helpee was to focus attention on a candle and to indicate lapses in attention by pressing a button. In a within-subject design the task of the remote helper was either to assist the helpee in this effort or to engage in a distraction task. Electrodermal activity (EDA) and button presses from the helpee served as dependent variables. RESULTS AND CONCLUSION: Participants' performance in the psi-screening test did not exceed chance expectations. In the distant intention experiment with 30 sessions no distant intention effect could be found in the prespecified analyses. The results in the psi-screening test were not correlated with performance in the main experiment. However, we found a large negative correlation between self-reported exceptional experiences of the helper and two EDA variables, namely skin conductance level and number of non-specific skin conductance responses. This correlation, if replicated, can hardly be explained without the assumption of a distant interaction.

(1) Background: Mind-body interventions (MBI), such as meditation or other relaxation techniques, have become the focus of attention in the clinical and health sciences. Differences in the effects of induction techniques are being increasingly investigated. (2) Methods: Here, we compared changes in the individual experience of time, space, and self in 44 students in an integrative health-promotion program. They participated in a study employing mindfulness meditation and a relaxation intervention with one week between sessions, thus employing a within-subjects design. (3) Results: No significant differences were detected when subjective reports were compared directly after each intervention. However, we found significant sequence effects between t1 and t2, independent of the meditation type. The sense of self diminished, the present orientation increased, and the past and future orientations decreased in both interventions. (4) Conclusions: We propose using scales to assess subjective time, self, and space as basic constituents of experience to measure the specificity of intervention methods, as well as longitudinal changes.

This study is based on the relationship between meditation, the present moment, and psychophysiology. We employed the metronome task to operationalize the extension of the present moment. A pre-post longitudinal study was conducted. The performance in the metronome task was compared before and after the interventions (meditation, story). The aim was to assess whether physiological changes (heart, breathing) during meditation influence the temporal-integration (TI) of metronome beats. Mindfulness meditators either meditated (n = 41) or listened to a story (n = 43). The heart and breathing activity were recorded during the intervention and compared to a resting-state condition. By applying path analyses we found that meditation led to an increase of the duration of integration intervals at the slowest metronome frequency (inter-stimulus interval, ISI = 3 s). After meditation, the higher the heart-rate variability (i.e., the root mean square of successive differences, RMSSD), the longer the duration of integration intervals at the fastest frequency (ISI = 0.33 s). Moreover, the higher the breathing rate during meditation, the greater the integration of intervals at ISI = 1 s. These findings add evidence to meditation-induced changes on the TI of metronome beats and the concept of the embodiment of mental functioning.

Several studies investigating psychophysiological correlates of false memories suggest that psychophysiology may provide incremental information to subjectively reported memory. Based on previous findings in a Deese-Roediger-McDermott paradigm, we examined three components of event-related EEG potentials of memory in a misleading information paradigm. 39 participants watched a video that included eight randomized details (e.g., the color of an envelope). After a retention interval of one week, four out of eight details were replaced by misleading details in a narrative text. Afterward, EEG was derived during a recognition test. First, we found that the amplitude at parietal electrodes did not differ between true and false memories. Instead, parietal positivity was more pronounced during yes- compared to no-responses, indicating parietal positivity reflects subjectively reported memory. Second, we found more positive frontal amplitudes associated with false compared to true memories in late time windows. Consequently, our findings indicate that false memories differ from true memories with respect to late frontal activation. In conclusion, we assume that parietal positivity reflects subjectively experienced memory, whereas late frontal activation holds incremental information to the subjectively experienced and reported memory.

The Concealed Information Test (CIT) is a valid method to detect hidden knowledge by means of psychophysiological measures. Concealing information is always a social behavior; yet, the role of social aspects has barely been investigated in recent CIT research favoring standardized, computer-based experiments. Evaluative observation is known to influence social behavior as well as physiological measures; examining the impact of evaluative observation on physiological responding in a CIT is the aim of this study. Sixty-three students completed a mock-crime and then underwent a CIT. In a between-subjects manipulation, half of the participants were observed through a camera and were faced with the real-time video of the experimenter watching them while completing the CIT. The other half completed the CIT without observation and video. Electrodermal activity, respiration line length, phasic heart rate, and finger pulse waveform length were registered. A specific questionnaire captured the individual fear of negative evaluation. Typical differential CIT responses occurred in both groups and with each measure. Contrary to expectations, differential CIT responses did not differ between groups. No modulatory influence of the fear questionnaire score on physiological responding was found. A ceiling effect, involving high attention and high motivation to avoid detection as well as high arousal in both groups due to the CIT procedure per se is discussed as explanation for these results, while the independence of the orienting reflex of social and motivational influence appears less likely in the light of previous literature.

During the observation of an ambiguous figure our perception alternates between mutually exclusive interpretations, although the stimulus itself remains unchanged. The rate of these endogenous reversals has been discussed as reflecting basic aspects of endogenous brain dynamics. Recent evidence indicates that extensive meditation practice evokes long-term functional and anatomic changes in the brain, also affecting the endogenous brain dynamics. As one of several consequences the rate of perceptual reversals during ambiguous figure perception decreases. In the present study we compared EEG-correlates of endogenous reversals of ambiguous figures between meditators and non-meditating controls in order to better understand timing and brain locations of this altered endogenous brain dynamics. A well-established EEG paradigm was used to measure the neural processes underlying endogenous perceptual reversals of ambiguous figures with high temporal precision. We compared reversal-related ERPs between experienced meditators and non-meditating controls. For both groups we found highly similar chains of reversal-related ERPs, starting early in visual areas, therewith replicating previous findings from the literature. Meditators, however, showed an additional frontal ERP signature already 160 ms after stimulus onset (Frontal Negativity). We interpret the additional, meditation-specific ERP results as evidence that extensive meditation practice provides control of frontal brain areas over early sensory processing steps. This may allow meditators to overcome phylogenetically evolved perceptual and attentional processing automatisms.

Unexpected cognitive lucidity and communication in patients with severe dementias, especially around the time of death, have been observed and reported anecdotally. Here, we review what is known about this phenomenon, related phenomena that provide insight into potential mechanisms, ethical implications, and methodologic considerations for systematic investigation. We conclude that paradoxical lucidity, if systematically confirmed, challenges current assumptions and highlights the possibility of network-level return of cognitive function in cases of severe dementias, which can provide insight into both underlying neurobiology and future therapeutic possibilities.

Mindfulness training is a novel method of leader development but contrary to its rising popularity, there is a scarcity of research investigating how mindfulness training may affect leader capabilities. To gain a better understanding of the potential of a new research field, qualitative research is advantageous. We sought to understand how senior leaders experience the impact of mindfulness training in their work lives and leadership ability. The sample comprised 13 leaders (n = 11 male) working in six organizations that completed a 10-week workplace mindfulness training (WMT). We conducted semi-structured interviews 6 to 12 months following course completion. We analyzed the data following thematic analysis steps and based on these findings, we devised a framework of the perceived impact of mindfulness training on self-leadership and leadership capabilities. We show that WMT exhibited impact on three self-leadership capacities: mindful task management, self-care and self-reflection and two leadership capacities: relating to others and adapting to change. Participants' recounts additionally suggested effects may expand to the level of the team and the organization. We show that WMT may be a promising tool for self-directed leadership development and outline avenues for future research.

The minimal neural correlate of the conscious state, regardless of the neural activity correlated with the ever-changing contents of experience, has still not been identified. Different attempts have been made, mainly by comparing the normal waking state to seemingly unconscious states, such as deep sleep or general anesthesia. A more direct approach would be the neuroscientific investigation of conscious states that are experienced as free of any specific phenomenal content. Here we present serendipitous data on content-free awareness (CFA) during an EEG-fMRI assessment reported by an extraordinarily qualified meditator with over 50,000 h of practice. We focused on two specific cortical networks related to external and internal awareness, i.e., the dorsal attention network (DAN) and the default mode network (DMN), to explore the neural correlates of this experience. The combination of high-resolution EEG and ultrafast fMRI enabled us to analyze the dynamic aspects of fMRI connectivity informed by EEG power analysis. The neural correlates of CFA were characterized by a sharp decrease in alpha power and an increase in theta power as well as increases in functional connectivity in the DAN and decreases in the posterior DMN. We interpret these findings as correlates of a top-down-initiated attentional state excluding external sensory stimuli and internal mentation from conscious experience. We conclude that the investigation of states of CFA could provide valuable input for new methodological and conceptual approaches in the search for the minimal neural correlate of consciousness.

With our attitudes and behavior, which aim at promoting sustainable behavior, we face a temporal dilemma - a temporal conflict between short-term and long-term interests. Accordingly, psychological time is an essential variable in understanding how people decide between options of short-term self-interest, which can be experienced at present, and long-term common interest, such as sustainable development with an outcome that lies far in the future. Present feelings are often so powerful that considerations of future events are neglected. Individuals differ in their emphasis on present and future dimensions. A stronger future orientation and a mindful present orientation are positive predictors of sustainable behavior; hedonistic and impulsive present orientations are negative predictors. We discuss the concept of the balanced time perspective as the propensity to consciously switch among the time orientations of past, present, and future. Fitting with their overall psychological profile, individuals with a balanced time perspective might display a range of sustainable attitudes and behaviors.