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There is lack of research on effects of red wine on consciousness when drank in wine bars designed to enhance the pleasurableness of the wine drinking experience. Effects of a moderate dose of red wine (≈ 40.98 g of ethanol) on consciousness were examined in a naturalistic study taking place in a wine bar located in one of the most touristic areas of Lisbon, Portugal. One hundred two participants drank in one of three conditions: alone, in dyad, or in groups up to six people. Red wine increased pleasure and arousal, decreased the awareness of time, slowed the subjective passage of time, increased the attentional focus on the present moment, decreased body awareness, slowed thought speed, turned imagination more vivid, and made the environment become more fascinating. Red wine increased insightfulness and originality of thoughts, increased sensations of oneness with the environment, spiritual feelings, all-encompassing love, and profound peace. All changes in consciousness occurred regardless of volunteers drinking alone, in dyad or in group. Men and women did not report different changes in consciousness. Older age correlated with greater increases in pleasure. Younger age correlated with greater increases in fascination with the environment of the wine bar. Drinking wine in a contemporaneous Western environment designed to enhance the pleasurableness of the wine drinking experience may trigger changes in consciousness commonly associated with mystical-type states.

Current theories about visual perception assume that our perceptual system weights the a priori incomplete, noisy and ambiguous sensory information with previous, memorized perceptual experiences in order to construct stable and reliable percepts. These theories are supported by numerous experimental findings. Theories about precognition have an opposite point of view. They assume that information from the future can have influence on perception, thoughts, and behavior. Several experimental studies provide evidence for precognition effects, other studies found no such effects. One problem may be that the vast majority of precognition paradigms did not systematically control for potential effects from the perceptual history. In the present study, we presented ambiguous Necker cube stimuli and disambiguated cube variants and systematically tested in two separate experiments whether perception of a currently observed ambiguous Necker cube stimulus can be influenced by a disambiguated cube variant, presented in the immediate perceptual past (perceptual history effects) and/or in the immediate perceptual future (precognition effects). We found perceptual history effects, which partly depended on the length of the perceptual history trace but were independent of the perceptual future. Results from some individual participants suggest on the first glance a precognition pattern, but results from our second experiment make a perceptual history explanation more probable. On the group level, no precognition effects were statistically indicated. The perceptual history effects found in the present study are in confirmation with related studies from the literature. The precognition analysis revealed some interesting individual patterns, which however did not allow for general conclusions. Overall, the present study demonstrates that any future experiment about sensory or extrasensory perception urgently needs to control for potential perceptual history effects and that temporal aspects of stimulus presentation are of high relevance.

We aimed to validate four established questionnaires related to time perception in German (Consideration of Future Consequences-14 scale (CFC-14), Boredom Proneness Scale (BPS), Metacognitive Questionnaire on Time (MQT), and Self-Awareness Questionnaire (SAQ)) using a back-translation method. Exploratory factor analyses were conducted on the data of 273 German-speaking participants to evaluate the factorial structures. Internal consistencies indicated good reliability values of the questionnaires and the respective subscales, except for the MQT. Intercorrelations between the questionnaires were examined to test their external validities and gain additional insight into the associations among the constructs. The consideration of future consequences was negatively linked to boredom proneness, whereas interoceptive awareness of one's bodily sensations was positively associated with boredom proneness. Additionally, interoceptive awareness was linked to metacognitive beliefs about which factors influence time perception. The results are discussed in regard to human time perception. Conclusion: The validated German questionnaires can now be used in research projects. Initial observations on how the questionnaires are related to each other fit the current knowledge on how human time perception works, yielding the first evidence for the external validity of the German versions of these established questionnaires. For evidence of criterion validity, future studies should more thoroughly investigate the external validities analyzing the correlations with other validated measures.

Boredom is an everyday experience during uneventful situations and while waiting. Such situations are typically described as unpleasant since oneself becomes the focus of awareness, and the subjective duration expands. Self-control is an individual trait that helps to cope with unpleasant situations. Hardly any systematic studies exist on real waiting situations where people's boredom and subjective time experience are assessed in relation to self-control. Therefore, we assessed 99 participants who first filled out self-report questionnaires on emotional and metacognitive control, the Scale for Experiencing Emotions (SEE) and the Temporal Metacognition Scale (TMCS). After giving a fake reason for why they had to wait, participants were shut in an empty room alone for 7.5 minutes and afterwards asked to report their impressions regarding the experienced time and reactions to the situation. Boredom was associated with the feeling of time passing more slowly and more frequent thoughts about time. The propensity to self-regulate was related to less awareness of time and to lower levels of boredom. Mediation analyses revealed that the level of boredom mediates the relationships between self-regulation processes and time perception. The results provide new insights into the association between time perception and boredom as states in a real situation and self-regulation as a trait.

Effortless learning during sleep is everybody's dream. Several studies found that presenting odor cues during learning and selectively during slow wave sleep increases learning success. The current study extends previous research in three aspects to test for optimization and practical applicability of this cueing effect: We (1) performed a field study of vocabulary-learning in a regular school setting, (2) stimulated with odor cues during the whole night without sleep monitoring, and (3) applied the odor additionally as retrieval cue in a subsequent test. We found an odor cueing effect with comparable effect sizes (d between 0.6 and 1.2) as studies with sleep monitoring and selective cueing. Further, we observed some (non-significant) indication for a further performance benefit with additional cueing during the recall test. Our results replicate previous findings and provide important extensions: First, the odor effect also works outside the lab. Second, continuous cueing at night produces similar effect sizes as a study with selective cueing in specific sleep stages. Whether odor cueing during memory recall further increases memory performance hast to be shown in future studies. Overall, our results extend the knowledge on odor cueing effects and provide a realistic practical perspective on it.

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.

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.

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.

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.

An approach toward detecting hidden knowledge is the Concealed Information Test (CIT). It relies on the memory of crime-relevant information. This study investigated whether its validity is susceptible to memory distortion by misleading information. A misleading information paradigm was employed to distort memory prior to an interrogation with a CIT. Forty-one participants watched a video with specific crime-related information. After a 1-week retention interval, misleading information was introduced. Afterward, a CIT was performed, followed by a threefold memory test. When misleading information was presented, memory performance was reduced, and no physiological response differences between crime-relevant and crime-irrelevant information were found. Without presenting misleading information, physiological responses differed between responses to crime-relevant and crime-irrelevant information. However, responses in all physiological measures also differed between misleading and irrelevant information. The results indicate that the CIT is susceptible to misleading information, which reduces its validity in specific constellations.

While the contingent negative variation (CNV) has been the subject of extensive research over the last fifty years, the maximum duration during which such cortical negativity can be maintained has, to the best of our knowledge, never been systematically explored. Participants were presented with the classic S1-S2 paradigm task, where a warning stimulus (S1) acts as a cue for the appearance of an imperative stimulus (S2). A fast motor response was required upon S2 arrival. Inter-stimulus intervals (ISIs) of 2.5, 5, 7.5 and 10 s duration were presented in blocked fashion. Data was analysed using both EEG referenced to linked mastoids and the current source density (CSD) technique, which maximizes the cortical origin of the measured voltage. Mean late CNV (lCNV) amplitude was found to be significantly higher for fast reaction time (RT) trials when CSD data was split according to the median into 'fast' and 'slow' RT halves. Post-hoc comparisons showed that this RT effect was particularly strong for the 10 s condition. This may be explained by the lack of an lCNV component and thus of cortical negativity prior to S2 in the 10 s condition. Our results suggest that intervals of a duration between 7.5 and 10 s represent the upper boundary during which the lCNV component can be elicited.

Our focus of attention naturally fluctuates between different sources of information even when we desire to focus on a single object. Focused attention (FA) meditation is associated with greater control over this process, yet the neuronal mechanisms underlying this ability are not entirely understood. Here, we hypothesize that the capacity of attention to transiently focus and swiftly change relates to the critical dynamics emerging when neuronal systems balance at a point of instability between order and disorder. In FA meditation, however, the ability to stay focused is trained, which may be associated with a more homogeneous brain state. To test this hypothesis, we applied analytical tools from criticality theory to EEG in meditation practitioners and meditation-naïve participants from two independent labs. We show that in practitioners-but not in controls-FA meditation strongly suppressed long-range temporal correlations (LRTC) of neuronal oscillations relative to eyes-closed rest with remarkable consistency across frequency bands and scalp locations. The ability to reduce LRTC during meditation increased after one year of additional training and was associated with the subjective experience of fully engaging one's attentional resources, also known as absorption. Sustained practice also affected normal waking brain dynamics as reflected in increased LRTC during an eyes-closed rest state, indicating that brain dynamics are altered beyond the meditative state. Taken together, our findings suggest that the framework of critical brain dynamics is promising for understanding neuronal mechanisms of meditative states and, specifically, we have identified a clear electrophysiological correlate of the FA meditation state.

AIM: The present study utilizes perceptual hysteresis effects to compare the ambiguity of Mona Lisa's emotional face expression (high-level ambiguity) and of geometric cube stimuli (low-level ambiguity). METHODS: In two experiments we presented series of nine Mona Lisa variants and nine cube variants. Stimulus ambiguity was manipulated by changing Mona Lisa's mouth curvature (Exp. 1) and the cubes' back-layer luminance (Exp. 2). Each experiment consisted of three conditions, two with opposite stimulus presentation sequences with increasing and decreasing degrees of ambiguity, respectively, and a third condition with a random presentation sequence. Participants indicated happy or sad face percepts (Exp. 1) and alternative 3D cube percepts (Exp. 2) by key presses. We studied the influences of a priori perceptual biases (long-term memory) and presentation order (short-term memory) on perception. RESULTS: Perception followed sigmoidal functions of the stimulus ambiguity morphing parameters. The morphing parameter for the functions' inflection points depended strongly on stimulus presentation order with similar effect sizes but different signs for the two stimulus types (positive hysteresis / priming for the cubes; negative hysteresis / adaptation for Mona Lisa). In the random conditions, the inflection points were located in the middle between those from the two directional conditions for the Mona Lisa stimuli. For the cube stimuli, they were superimposed on one sigmoidal function for the ordered condition. DISCUSSION: The hysteresis effects reflect the influence of short-term memory during the perceptual disambiguation of ambiguous sensory information. The effects for the two stimulus types are of similar size, explaining up to 34% of the perceptual variance introduced by the paradigm. We explain the qualitative difference between positive and negative hysteresis with adaptation for Mona Lisa and with priming for the cubes. In addition, the hysteresis paradigm allows a quantitative determination of the impact of adaptation and priming during the resolution of perceptual ambiguities. The asymmetric shifts of inflection points in the case of the cube stimuli is likely due to an a priori perceptual bias, reflecting an influence of long-term memory. Whether corresponding influences also exist for the Mona Lisa variants is so far unclear.

Research on meditation is advancing, but few studies about the motivations of meditators exist. Additionally, many forms and traditions of meditation have yet to be investigated. This study addresses both of these issues by presenting an overview of different forms of motivations found in contemporary Anthroposophic meditation practice. 30 Anthroposophic meditators were interviewed about their meditation experiences. The interviews were examined using thematic analysis. 14 data-driven themes were extracted and organized within a framework consisting of three superordinate theory-driven forms of motivation: External, internal and service. A developmental trajectory running from external and internal to service motivations is indicated. This approach improves upon a scheme developed by Shapiro by including additional types of motivations and being able to differentiate between forms of motivations that are fundamentally different: Self-related (heteronomous and autonomous) motivations and other-related motivations.