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Empirical findings in the Cognitive Sciences on the relationship between feeling states and subjective time have led to the assumption that time perception entails emotional and interoceptive states. The perception of time would thereafter be embodied; the bodily self, the continuous input from the body is the functional anchor of phenomenal experience and the mental self. Subjective time emerges through the existence of the self across time as an enduring and embodied entity. This relation is prominently disclosed in studies on altered states of consciousness such as in meditative states, under the influence of hallucinogens as well as in many psychiatric and neurological conditions. An increased awareness of oneself coincides with an increased awareness of time. Conversely, a decreased awareness of the self is associated with diminished awareness of time. The body of empirical work within different conceptual frameworks on the intricate relationship between self and time is presented and discussed.

In the general concept of self-disturbances in schizophrenia and schizophrenia spectrum disorders, somatopsychic depersonalization (SPD) occupies a special place as it constitutes a syndrome that comprises feelings of detachment from one's own body and mental processes. However, apart from clinical descriptions, to date the pathophysiology of SPD is not fully understood due to the rareness of the syndrome and a lack of experimental studies. In a case study of one patient with schizotypal disorder, we applied a multimodal approach to understanding the SPD phenomena. The patient's clinical profile was identified as disruption of implicit bodily function, accompanied by depressive symptoms. On a neuropsychological level, the patient exhibited impairment in executive functioning, intact tactile perception and kinesthetic praxis. Behavioral tests revealed an altered sense of time but unimpaired self-agency. Furthermore, the patient exhibited a lack of empathy and he had autistic traits, although with a sufficient ability to verbalize his feelings. On the neurobiological level using an active and passive touch paradigm during functional magnetic resonance imaging (fMRI), we found a hyperconnectivity of the default-mode network and salience network and a hypoconnectivity of the central executive brain networks in the performance of the touch task as well as intact perceptual touch processing emerging from the direct comparisons of the touch conditions. Our data provide evidence for the important role of altered large-brain network functioning in SPD that corresponds to the specific behavioral and neurocognitive phenomena.

BACKGROUND: Nearly half of individuals with substance use disorders relapse in the year after treatment. A diagnostic tool to help clinicians make decisions regarding treatment does not exist for psychiatric conditions. Identifying individuals with high risk for relapse to substance use following abstinence has profound clinical consequences. This study aimed to develop neuroimaging as a robust tool to predict relapse. METHODS: 68 methamphetamine-dependent adults (15 female) were recruited from 28-day inpatient treatment. During treatment, participants completed a functional MRI scan that examined brain activation during reward processing. Patients were followed 1 year later to assess abstinence. We examined brain activation during reward processing between relapsing and abstaining individuals and employed three random forest prediction models (clinical and personality measures, neuroimaging measures, a combined model) to generate predictions for each participant regarding their relapse likelihood. RESULTS: 18 individuals relapsed. There were significant group by reward-size interactions for neural activation in the left insula and right striatum for rewards. Abstaining individuals showed increased activation for large, risky relative to small, safe rewards, whereas relapsing individuals failed to show differential activation between reward types. All three random forest models yielded good test characteristics such that a positive test for relapse yielded a likelihood ratio 2.63, whereas a negative test had a likelihood ratio of 0.48. CONCLUSIONS: These findings suggest that neuroimaging can be developed in combination with other measures as an instrument to predict relapse, advancing tools providers can use to make decisions about individualized treatment of substance use disorders.

Intuitively, being aware of one's inner processes to move should be crucial for the control of voluntary movements. However, research findings suggest that we are not always aware of the processes leading to movement execution. The present study investigated induced first-person access to inner processes of movement initiation and the underlying brain activities which contribute to the emergence of voluntary movement. Moreover, we investigated differences in task performance between mindfulness meditators and non-meditators while assuming that meditators are more experienced in attending to their inner processes. Two Libet-type tasks were performed; one in which participants were asked to press a button at a moment of their own decision, and the other one in which participants' attention was directed towards their inner processes of decision making regarding the intended movement which lead them to press the button. Meditators revealed a consistent readiness potential (RP) between the two tasks with correlations between the subjective intention time to act and the slope of the early RP. However, non-meditators did not show this consistency. Instead, elicited introspection of inner processes of movement initiation changed early brain activity that is related to voluntary movement processes. Our findings suggest that compared to non-meditators, meditators are more able to access the emergence of negative deflections of slow cortical potentials (SCPs), which could have fundamental effects on initiating a voluntary movement with awareness.

INTRODUCTION: Trait sexual motivation defines a psychological construct that reflects the long-lasting degree of motivation for sexual activities, which is assumed to be the result of biological and sociocultural influences. With this definition, it shares commonalities with other sexuality-related constructs like sexual desire, sexual drive, sexual needs, and sexual compulsivity. AIM: The Trait Sexual Motivation Questionnaire (TSMQ) was developed in order to measure trait sexual motivation with its different facets. METHODS: Several steps were conducted: First, items were composed assessing sexual desire, the effort made to gain sex, as well as specific sexual behaviors. Factor analysis of the data of a first sample (n = 256) was conducted. Second, the factor solution was verified by a confirmatory factor analysis in a second sample (n = 498) and construct validity was demonstrated. Third, the temporal stability of the TSMQ was tested in a third study (n = 59). MAIN OUTCOME MEASURE: Questionnaire data. RESULTS: The exploratory and confirmatory factor analyses revealed that trait sexual motivation is best characterized by four subscales: Solitary Sexuality, Importance of Sex, Seeking Sexual Encounters, and Comparison with Others. It could be shown that the test quality of the questionnaire is high. Most importantly for the trait concept, the retest reliability after 1 year was r = 0.87. CONCLUSION: Our results indicate that the TSMQ is indeed a suitable tool for measuring long-lasting sexual motivation with high test quality and high construct validity. A future differentiation between trait and state sexual motivation might be helpful for clinical as well as forensic research.

Perception of ambiguous figures is unstable and alternates repeatedly between possible interpretations. Some approaches to explaining this phenomenon have, so far, assumed low-level bottom-up mechanisms like adaptation and mutual inhibition of underlying neural assemblies. In contrast, less precise top-down approaches assume high-level attentional control mechanisms generalised across sensory modalities. In the current work we focused on specific aspects of the top-down approach. In a first study we used dwell times (periods of transiently stable percepts) and the parameters of dwell time distribution functions to compare the dynamics of perceptual alternations between visual (Necker cube) and auditory ambiguity (verbal transformation effect). In a second study we compared the endogenous alternation dynamics of the Necker cube with parameters from two attention tasks with different regimes of temporal dynamics. The first attention task (d2) is characterised by endogenous self-paced dynamics, similar to the dynamics underlying perceptual alternations of ambiguous figures, and we found clear correlations between dwell time parameters (Necker cube) and processing speed (d2 task). The temporal dynamics of the second (go/no-go) attention task, in contrast, are exogenously governed by the stimulus protocol, and we found no statistically significant correlation with the Necker cube data. Our results indicate that both perceptual instability and higher-level attentional tasks are linked to endogenous brain dynamics on a global coordinating level beyond sensory modalities.

Although research on the effects of mindfulness meditation (MM) is increasing, still very little has been done to address its influence on the white matter (WM) of the brain. We hypothesized that the practice of MM might affect the WM microstructure adjacent to five brain regions of interest associated with mindfulness. Diffusion tensor imaging was employed on samples of meditators and non-meditators (n = 64) in order to investigate the effects of MM on group difference and aging. Tract-Based Spatial Statistics was used to estimate the fractional anisotrophy of the WM connected to the thalamus, insula, amygdala, hippocampus, and anterior cingulate cortex. The subsequent generalized linear model analysis revealed group differences and a group-by-age interaction in all five selected regions. These data provide preliminary indications that the practice of MM might result in WM connectivity change and might provide evidence on its ability to help diminish age-related WM degeneration in key regions which participate in processes of mindfulness.

Recent research suggests that bodily signals and interoception are strongly related to our sense of time. Mindfulness meditators train to be aware of their body states and therefore could be more accurate at interval timing. In this study, n = 22 experienced mindfulness meditators and n = 22 matched controls performed both, an acoustic and a visual duration reproduction task of 8, 14, and 20 s intervals, while heart rate and skin conductance were continuously assessed. In addition, participants accomplished a heart beat perception task and two selective attention tasks. Results revealed no differences between meditators and controls with respect to performance in duration reproduction or attentional capacities. Additionally no group difference in heart beat perception scores was found. Across all subjects, correlational analyses revealed several associations between performance in the duration reproduction tasks and psychophysiological changes, the latter being also related to heart beat perception scores. Furthermore, former findings of linearly increasing cardiac periods and decreasing skin conductance levels during the auditory duration estimation task (Meissner and Wittmann, 2011) could be replicated, and these changes could also be observed during a visual duration reproduction task. In contrast to our earlier findings, the heart beat perception test was not related with timing performance. Overall, although experienced meditators did not differ from matched controls with respect to duration reproduction and interoceptive awareness, this study adds significantly to the emerging view that time perception is related to autonomic regulation and awareness of body states.

The study aimed at experimentally investigating whether the human body can anticipate future events under improved methodological conditions. Previous studies have reported contradictory results for the phenomenon typically called presentiment. If the positive findings are accurate, they call into doubt our views about human perception, and if they are inaccurate, a plausible conventional explanation might be based on the experimental design of the previous studies, in which expectation due to item sequences was misinterpreted as presentiment. To address these points, we opted to collect several physiological variables, to test different randomization types and to manipulate subjective significance individually. For the latter, we combined a mock crime scenario, in which participants had to steal specific items, with a concealed information test (CIT), in which the participants had to conceal their knowledge when interrogated about items they had stolen or not stolen. We measured electrodermal activity, respiration, finger pulse, heart rate (HR), and reaction times. The participants (n = 154) were assigned randomly to four different groups. Items presented in the CIT were either drawn with replacement (full) or without replacement (pseudo) and were either presented category-wise (cat) or regardless of categories (nocat). To understand how these item sequences influence expectation and modulate physiological reactions, we compared the groups with respect to effect sizes for stolen vs. not stolen items. Group pseudo_cat yielded the highest effect sizes, and pseudo_nocat yielded the lowest. We could not find any evidence of presentiment but did find evidence of physiological correlates of expectation. Due to the design differing fundamentally from previous studies, these findings do not allow for conclusions on the question whether the expectation bias is being confounded with presentiment.

Cognitive reappraisal and expressive suppression, two major emotion regulation strategies, are differentially related to emotional well-being. The aim of this study was to test the association of individual differences in these two emotion regulation strategies with gray matter volume of brain regions that have been shown to be involved in the regulation of emotions. Based on high-resolution magnetic resonance images of 96 young adults voxel-based morphometry was used to analyze the gray matter volumes of the a priori regions of interest, including amygdala, insula, dorsal anterior cingulate and paracingulate cortex, medial and lateral prefrontal cortex (PFC) and their association with cognitive reappraisal and expressive suppression usage as well as neuroticism. A positive association of cognitive reappraisal with right and tendentially left amygdala volume and of neuroticism with left amygdala volume (marginally significant) was found. Expressive suppression was related to dorsal anterior cingulate/paracingulate cortex and medial PFC gray matter volume. The results of this study emphasize the important role of the amygdala in individual differences in cognitive reappraisal usage as well as neuroticism. Additionally, the association of expressive suppression usage with larger volumes of the medial PFC and dorsal anterior/paracingulate cortex underpins the role of these regions in regulating emotion-expressive behavior.