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Abstracts
  • Pütz, P., Wittmann, M., & Wackermann, J. (2012). Duration reproduction: lossy integration and effects of sensory modalities, cognitive functioning, age, and sex. Perceptual and Motor Skills, 115(2), 370–384. https://doi.org/10.2466/22.10.27.PMS.115.5.370-384

    The "dual klepsydra model" (DKM) of internal time representation successfully models duration reproduction data, but relations between the DKM-based parameter kappa ("loss rate") and procedural variables (presentation modality) or individual characteristics (cognitive indices, age, sex) remained as yet unexplored. For that purpose, were-analyzed data from an earlier time reproduction study (N = 100), using visually or acoustically presented intervals of 1-5 sec. duration. Typical values of parameter kappa were approximately 0.03-0.04 sec.(-1), corresponding to relaxation times of internal "lossy integrators" of approximately 30 sec. Significant effects of presentation modality (smaller kappa values for the visual reproduction task) and of age (greater kappa in acoustic reproduction with increasing age) were observed. Cognitive variables (working memory, general fluid reasoning, attention) and sex of participants were not associated with kappa. Cognitive functions seem to play only a minor, if any, role at the level of time representation addressed by the DKM.

  • Kübel, S. L., Fiedler, H., & Wittmann, M. (2021). Red visual stimulation in the Ganzfeld leads to a relative overestimation of duration compared to green. PsyCh Journal, 10(1), 5–19. https://doi.org/10.1002/pchj.395

    A Ganzfeld is a homogenized visual and auditory perceptual field which can induce altered states of consciousness (ASC; Metzger, 1929; Schmidt & Prein, 2019). Using a balanced intrasubject design, we compared participants' experience during two differently colored (red, green) 25-min Ganzfeld sessions with brown noise as acoustic stimulation. Participants were exposed to the colored visual field through commercially available goggles and to brown noise over headphones. We selected 67 participants with some prior meditation experience to increase the probability that they would engage meaningfully with this specifically restricted stimulus situation. We tested the functional components of the standard cognitive model of time perception (Zakay & Block, 1997) in a path analysis for direct (red vs. green light) and indirect effects (arousal, attention) on subjective duration and perceived passage of time. Subjective arousal and valence states were measured using the Self-Assessment Manikin (SAM). The amount of attention directed to time and the perceived passage of time were rated with standard visual analog scales (VAS). Participants also estimated the duration of each Ganzfeld exposure. The session with the red visual field lasted significantly longer than did the green session (μ(red) = 23.1 min; μ(green) = 19.8 min). After the green session, participants rated their arousal level to have significantly decreased; after the red session, individuals on average felt emotionally less positive. Multiple path analyses revealed that the effect of color on estimated duration is completely mediated through higher arousal levels during the red Ganzfeld session. In turn, the higher arousal level generates a longer subjective estimate of duration. For induction of relaxation in studies probing altered states of consciousness employing the Ganzfeld technique, we recommend using the green light.

  • Ulbrich, P., Churan, J., Fink, M., & Wittmann, M. (2009). Perception of temporal order: the effects of age, sex, and cognitive factors. Neuropsychology, Development, and Cognition. Section B, Aging, Neuropsychology and Cognition, 16(2), 183–202. https://doi.org/10.1080/13825580802411758

    The present paper investigates the effects of age, sex, and cognitive factors on temporal-order perception. Nine temporal-order tasks were employed using two and four stimuli presented in the auditory and visual modalities. Significantly increased temporal-order thresholds (TOT) in the elderly were found for almost all tasks, while sex differences were only observed for two tasks. Multiple regression analyses show that the performance on most temporal-order tasks can be predicted by cognitive factors, such as speed of fluid reasoning, short-term memory, and attention. However, age was a significant predictor of TOT in three tasks using visual stimuli. We conclude (1) that age-related differences can often be attributed to cognitive factors involved in temporal-order perception, and (2) that the concept of temporal-order perception is more complex than implied by the current models.

  • Gutyrchik, E., Churan, J., Meindl, T., Bokde, A. L. W., von Bernewitz, H., Born, C., Reiser, M., Pöppel, E., & Wittmann, M. (2010). Functional neuroimaging of duration discrimination on two different time scales. Neuroscience Letters, 469(3), 411–415. https://doi.org/10.1016/j.neulet.2009.12.040

    Analyses of neural mechanisms of duration processing are essential for the understanding of psychological phenomena which evolve in time. Different mechanisms are presumably responsible for the processing of shorter (below 500 ms) and longer (above 500 ms) events but have not yet been a subject of an investigation with functional magnetic resonance imaging (fMRI). In the present study, we show a greater involvement of several brain regions - including right-hemispheric midline structures and left-hemispheric lateral regions - in the processing of visual stimuli of shorter as compared to longer duration. We propose a greater involvement of lower-level cognitive mechanisms in the processing of shorter events as opposed to higher-level mechanisms of cognitive control involved in longer events.

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Last update from database: 11.08.25, 05:41 (UTC)