Attention delays perceived stimulus offset

AbstractYeshurun and Levy (2003) [Transient spatial attention degrades temporal resolution. Psychological Science, 14, 225 –231.] have suggested that visual attention enhances the activation of the parvocellular system and thus delays the perceived offset of a stimulus. We tested this assumption in a spatial cueing paradigm in which participants responded to stimulus offset. Consistent with this assumption, offset reaction time (RT) was prolonged for attended compared to unattended stimuli. For onset RT, however, we confirmed the well-known spatial cueing effect that attention speeds up the detection of stimulus onset. The results provide direct evidence for the proposal made by Yeshurun and Levy

Untersuchungen zu Prädiktoren für das Therapieansprechen einer antiviralen Kombinationstherapie mit pegyliertem Interferon und Ribavirin bei chronischer Hepatitis C Virusinfektion

Das Ansprechen auf eine medikamentöse Therapie bei chronischer Hepatitis C ist von einer Vielzahl von Faktoren abhängig. Bei Kombinationstherapie mit pegyliertem Interferon und Ribavirin zeigt sich ein Therapieerfolg in Form eines dauerhaften virologischen Ansprechens lediglich bei durchschnittlich etwa 55 % der Patienten (Ferenci et al, 2005). Ziel der vorliegenden Arbeit ist deshalb die Identifikation von prognostischen Faktoren vor und während der Therapie, die zur Vorhersage des Therapieerfolges beitragen können. Im Rahmen der vorliegenden Studie wurden 293 Patienten erfasst, die an der Universitätsklinik Tübingen eine medikamentöse Therapie zur Behandlung einer chronischen Hepatitis C erhalten haben. 235 der Patienten wurden mit pegyliertem Interferon und Ribavirin behandelt. Ein positives Ergebnis der Therapie wird auf verschiedene Arten definiert und beinhaltet ein schnelles virologisches Ansprechen (rapid und complete responder), eine nicht nachweisbare Viruslast zur Woche 4 und ein dauerhaftes virologisches Ansprechen (sustained virological response, SVR). Nach Prüfung einer Vielzahl von demographischen und laborchemischen Parametern zeigten sich Alter, Genotyp, Vortherapie und GGT Ausgangswert als wichtige prädiktive Faktoren. Ein logistisches Regressionsmodell zur Vorhersage des Therapieerfolgs wurde unter Berücksichtigung dieser Prädiktoren erstellt. Anhand des Modelles wurde eine Einschätzung für den Therapieerfolg durchgeführt. Dabei variiert die Wahrscheinlichkeit eines Therapieerfolges deutlich, von prognostizierten 94% bei Patienten mit Genotyp 2/3, ohne Vortherapie, unter 47 Jahren und normgerechtem GGT Ausgangswert, bis zu einer Erfolgswahrscheinlichkeit von 13% bei Patienten mit Genotyp 1/4, mit Vortherapie, Alter über 47 Jahren und erhöhtem GGT Ausgangswert. Jede mögliche Kombination der hier erfassten prädiktiven Faktoren wurde mit der damit assoziierten Erfolgswahrscheinlichkeit tabellarisch dargestellt, um eine sinnvolle Abschätzung des Therapieerfolges vor Therapiebeginn zu ermöglichen. Eine Vorhersage des Therapieerfolgs während der Therapie anhand verschiedener untersuchter Blutbildveränderungen ist nach den vorliegenden Ergebnissen nur bedingt möglich. Lediglich die Verläufe von Hb-Wert, GGT und ALT scheinen hierbei indikativ für das dauerhafte Therapieansprechen zu sein

Stochastic accumulation of feature information in perception and memory

It is now well established that the time course of perceptual processing influences the first second or so of performance in a wide variety of cognitive tasks. Over the last20 years, there has been a shift from modeling the speed at which a display is processed, to modeling the speed at which different features of the display are perceived and formalizing how this perceptual information is used in decision making. The first of these models(Lamberts, 1995) was implemented to fit the time course of performance in a speeded perceptual categorization task and assumed a simple stochastic accumulation of feature information. Subsequently, similar approaches have been used to model performance in a range of cognitive tasks including identification, absolute identification, perceptual matching, recognition, visual search, and word processing, again assuming a simple stochastic accumulation of feature information from both the stimulus and representations held in memory. These models are typically fit to data from signal-to-respond experiments whereby the effects of stimulus exposure duration on performance are examined, but response times (RTs) and RT distributions have also been modeled. In this article, we review this approach and explore the insights it has provided about the interplay between perceptual processing, memory retrieval, and decision making in a variety of tasks. In so doing, we highlight how such approaches can continue to usefully contribute to our understanding of cognition

Time perception: the bad news and the good.

Time perception is fundamental and heavily researched, but the field faces a number of obstacles to theoretical progress. In this advanced review, we focus on three pieces of 'bad news' for time perception research: temporal perception is highly labile across changes in experimental context and task; there are pronounced individual differences not just in overall performance but in the use of different timing strategies and the effect of key variables; and laboratory studies typically bear little relation to timing in the 'real world'. We describe recent examples of these issues and in each case offer some 'good news' by showing how new research is addressing these challenges to provide rich insights into the neural and information-processing bases of timing and time perception. WIREs Cogn Sci 2014, 5:429-446. doi: 10.1002/wcs.1298 This article is categorized under: Psychology > Perception and Psychophysics Neuroscience > Cognition.This is the final published version. It originally appeared at http://onlinelibrary.wiley.com/doi/10.1002/wcs.1298/abstract, published by Wiley

Visual adaptation enhances action sound discrimination

Prolonged exposure, or adaptation, to a stimulus in one modality can bias, but also enhance, perception of a subsequent stimulus presented within the same modality. However, recent research has also found that adaptation in one modality can bias perception in another modality. Here we show a novel crossmodal adaptation effect, where adaptation to a visual stimulus enhances subsequent auditory perception. We found that when compared to no adaptation, prior adaptation to visual, auditory or audiovisual hand actions enhanced discrimination between two subsequently presented hand action sounds. Discrimination was most enhanced when the visual action ‘matched’ the auditory action. In addition, prior adaptation to a visual, auditory or audiovisual action caused subsequent ambiguous action sounds to be perceived as less like the adaptor. In contrast, these crossmodal action aftereffects were not generated by adaptation to the names of actions. Enhanced crossmodal discrimination and crossmodal perceptual aftereffects may result from separate mechanisms operating in audiovisual action sensitive neurons within perceptual systems. Adaptation induced crossmodal enhancements cannot be explained by post-perceptual responses or decisions. More generally, these results together indicate that adaptation is a ubiquitous mechanism for optimizing perceptual processing of multisensory stimuli

Motor activity improves temporal expectancy

Certain brain areas involved in interval timing are also important in motor activity. This raises the possibility that motor activity might influence interval timing. To test this hypothesis, we assessed interval timing in healthy adults following different types of training. The pre- and post-training tasks consisted of a button press in response to the presentation of a rhythmic visual stimulus. Alterations in temporal expectancy were evaluated by measuring response times. Training consisted of responding to the visual presentation of regularly appearing stimuli by either: (1) pointing with a whole-body movement, (2) pointing only with the arm, (3) imagining pointing with a whole-body movement, (4) simply watching the stimulus presentation, (5) pointing with a whole-body movement in response to a target that appeared at irregular intervals (6) reading a newspaper. Participants performing a motor activity in response to the regular target showed significant improvements in judgment times compared to individuals with no associated motor activity. Individuals who only imagined pointing with a whole-body movement also showed significant improvements. No improvements were observed in the group that trained with a motor response to an irregular stimulus, hence eliminating the explanation that the improved temporal expectations of the other motor training groups was purely due to an improved motor capacity to press the response button. All groups performed a secondary task equally well, hence indicating that our results could not simply be attributed to differences in attention between the groups. Our results show that motor activity, even when it does not play a causal or corrective role, can lead to improved interval timing judgments

Numerical magnitude affects temporal memories but not time encoding

Previous research has suggested that the perception of time is influenced by concurrent magnitude information (e.g., numerical magnitude in digits, spatial distance), but the locus of the effect is unclear, with some findings suggesting that concurrent magnitudes such as space affect temporal memories and others suggesting that numerical magnitudes in digits affect the clock speed during time encoding. The current paper reports 6 experiments in which participants perceived a stimulus duration and then reproduced it. We showed that though a digit of a large magnitude (e.g., 9), relative to a digit of a small magnitude (e.g., 2), led to a longer reproduced duration when the digits were presented during the perception of the stimulus duration, such a magnitude effect disappeared when the digits were presented during the reproduction of the stimulus duration. These findings disconfirm the account that large numerical magnitudes accelerate the speed of an internal clock during time encoding, as such an account incorrectly predicts that a large numerical magnitude should lead to a shorter reproduced duration when presented during reproduction. Instead, the findings suggest that numerical magnitudes, like other magnitudes such as space, affect temporal memories when numerical magnitudes and temporal durations are concurrently held in memory. Under this account, concurrent numerical magnitudes have the chance to influence the memory of the perceived duration when they are presented during perception but not when they are presented at the reproduction stage

De la “esencia” de la Iglesia a su “identidad”. El cambio de paradigma eclesiológico en el Concilio Vaticano II

The II Vatican Council can be understood, in its intention, in its process and its results, as the Church´s attempt to affirm itself under a new historical situation, as an effort to assert its identity against the background of radical social changes in Europe and the world. In his opening speech of the second session of the Council, Paul VI declared the first goal of the council as “the self-understanding of the Church.” John XXIII expressed the intuition that guided him with a view to reconcile the conciliar project with the programmatic expression of aggiornamento. According to what he felt, the Church was “yesterday” and could not reach out to the world of “today” as its contemporary, being at the same height. It could not be a useful interlocutor for the man of today.El Concilio Vaticano II puede comprenderse, en su intención, en su proceso y en sus resultados, como el intento de la Iglesia de cerciorarse sobre sí misma en el marco de una nueva situación histórica; como un esfuerzo por afirmar la propia identidad sobre el trasfondo de radicales transformaciones sociales en Europa y el mundo. En su discurso inaugural del segundo período de sesiones del Concilio, Pablo VI declaró como primera meta del Concilio “la autocomprensión de la Iglesia”. Y Juan XXIII expresó la intuición que lo guiaba con vistas a su proyecto conciliar con la programática expresión aggiornamento. Según sentía, su Iglesia era “de ayer” y ya no podía salir al encuentro del mundo de “hoy” como contemporánea suya, estando a su misma altura. Ya no podía ser una interlocutora útil para el hombre de hoy