Cue type affects preparatory influences on task inhibition

The present study investigates the influence of preparation on inhibitory effects in cued task switching. In three experiments, we assessed n − 2 repetition costs as marker of inhibition of the just executed and now irrelevant task by comparing performance in task sequences such as ABA (i.e., n − 2 repetitions, with A, B and C standing for different tasks) to task sequences such as CBA (i.e., n − 2 switches). Specifically, we varied the cue–target interval (CTI) to examine cue-based preparation effects. In addition, we manipulated cue type (i.e., abstract, verbal, and direct cues) across the three experiments. We obtained significant reductions of n − 2 repetition costs with prolonged CTI when using abstract cues (i.e., coloured frames) and task names (i.e., digit), but not when using the task-specific stimulus–response mapping as cue for the upcoming task. These data suggest that cue-based preparation is not a uniform process but depends on the information provided by the cue.     

Perceptual complexity,rather than valence or arousal accounts for distracter-induced overproductions of temporal durations

For humans and other species, the ability to estimate the physical passage of time is of fundamental importance for perceptual, cognitive or motor functions. Despite this importance, any subjective estimation of temporal durations not only depends on the temporal dynamics of the to-be-timed stimulus or event, but also can be distorted by non-temporal perceptual, cognitive, and emotional effects. This study aimed to further explore critical stimulus characteristics modulating distracter-induced distortions in human time-reproduction. To this end, we investigated whether subjectively rated distracter dimensions of arousal and valence (related to levels of emotionality), or rather stimulus complexity, as a confounder, produce distortions in participants' reproduction of a previously trained target interval. Accuracy and precision of time-reproduction have been measured in distracter-trials, and compared to timing performance in baseline-trials without any distraction. Results showed temporal overproductions in a magnitude of less than distracter duration only for complex distracters. Most importantly, arousal level and valence of distracters were not accountable for temporal distortions. Within an internal clock framework, our pattern of results can best be interpreted in the context of attention-, rather than arousal-based mechanisms of timing.     

Emotional modulation of attention affects time perception: Evidence from event-related potentials

Emotional effects on human time perception are generally attributed to arousal speeding up or slowing down the internal clock. The aim of the present study is to investigate the less frequently considered role of attention as an alternative mediator of these effects with the help of event-related potentials (ERPs). Participants produced short intervals (0.9, 1.5, 2.7, and 3.3 s) while viewing high arousal images with pleasant and unpleasant contents in comparison to neutral images. Behavioral results revealed that durations were overproduced for the 0.9 s interval whereas, for 2.7 and 3.3 s intervals, underproduction was observed. The effect of affective valence was present for the shorter durations and decreased as the target intervals became longer. More specifically, the durations for unpleasant images were less overproduced in the 0.9 s intervals, and for the 1.5 s trials, durations for unpleasant images were slightly underproduced, compared to pleasant images, which were overproduced. The analysis of different ERP components suggests possible attention processes related to the timing of affective images in addition to changes in pacemaker speed. Early Posterior Negativity (EPN) was larger for positive than for negative images, indicating valence-specific differences in activation of early attention mechanisms. Within the early P1 and the Late Positive Potential (LPP) components, both pleasant and unpleasant stimuli exhibited equal affective modulation. Contingent Negative Variation (CNV) remained independent of both timing performance and affective modulation. This pattern suggests that both pleasant and unpleasant stimuli enhanced arousal and captured attention, but the latter effect was more pronounced for pleasant stimuli. The valence-specificity of affective attention revealed by ERPs combined with behavioral timing results suggests that attention processes indeed contribute to emotion-induced temporal distortions, especially for longer target intervals.     

A new perspective on visual word processing efficiency

As a fundamental part of our daily lives, visual word processing has received much attention in the psychological literature. Despite the well established advantage of perceiving letters in a word or in a pseudoword over letters alone or in random sequences using accuracy, a comparable effect using response times has been elusive. Some researchers continue to question whether the advantage due to word context is perceptual. We use the capacity coefficient, a well established, response time based measure of efficiency to provide evidence of word processing as a particularly efficient perceptual process to complement those results from the accuracy domain.     

Involvement of shared resources in time judgment and sequence reasoning tasks

Previous research suggests that time perception is supported by the same attentional resources involved in sequence processing. The present experiment was designed to clarify this connection by examining the relation between timing and reasoning tasks that involved either sequencing or non-sequencing judgments. For the timing task, subjects produced a series of 5-s intervals. For the reasoning tasks, subjects judged whether pairs of statements describing common actions either (a) were presented in the correct temporal order (sequencing), or (b) described similar actions or objects (similarity). Subjects performed the timing and reasoning tasks both separately and concurrently in a series of 3-minute trials. Comparisons of single-task and dual-task performance assessed interference patterns between concurrent tasks. Both reasoning tasks interfered with timing by making temporal productions longer and more variable. Timing had differential effects on the two reasoning tasks. Concurrent timing caused sequencing judgments to become slower, less accurate, and less sensitive relative to sequencing-only conditions. In contrast, similarity judgments were either unaffected or affected to a lesser degree by the concurrent timing task. These results support the notion that timing and sequencing are closely related processes that rely on the same set of cognitive resources or mechanisms.     

Priming as a way of understanding children’s mental representations of the social world

Priming is a well established tool for experimental examination of how mental representations drive thoughts, feelings, and behaviors that has been widely used in adult research. Priming is also a well established technique in cognitive development research. Social development research, however, has rarely used priming as a research method despite evidence that this technique is promising for helping researchers untangle causal connections between children’s mental representations and children’s social development outcomes. This paper discusses how priming methods may yield important insights into the role that children’s mental representations of the social world play in children’s social functioning. We begin by discussing the theoretical conceptualization underlying priming and priming methods. We next review evidence demonstrating the effectiveness of priming techniques in child development research. We conclude by suggesting ways in which priming can inform future research in social development using research examining attachment, social-information-processing, gender development, and mood and mental health as examples.     

Evidence that stakes don’t matter for evidence

Some philosophers have recently defended anti-intellectualism with respect to knowledge and evidence. In this paper, I assess anti-intellectualism about evidence, which claims a relation between one's evidence and the practical benefits or costs of being right or wrong about the propositions supported by that evidence. Proponents of anti-intellectualism generally regard their view as not at all obvious, but nonetheless strongly supported by appeal to our intuitive judgments about whether particular epistemic properties are instantiated in hypothetical cases. Anti-Intellectualism is thus taken by its proponents to be a surprising truth. I show that, though peoples’ explicit judgments about the general issue of whether or not non-epistemic factors make an epistemic difference are often in line with anti-intellectualism, their judgments about whether particular epistemic properties are instantiated in hypothetical cases do not display a pattern that would clearly support anti-intellectualism about evidence. Thus, anti-intellectualism about evidence is not entirely surprising, and intuitive assessments of hypothetical cases do not clearly support its truth.     

When motor congruency modulates immediate memory for objects

In line with the embodied cognition view, some researchers have suggested that our capacity to retain information relies on the perceptual and motor systems used to interact with our environment (Barsalou, 1999; Glenberg, 1997). For instance, the language production architecture would be responsible for the retention of verbal materials such as a list of words (Acheson & MacDonald, 2009). However, evidence for the role of the motor system in object memory is still limited. In the present experiments, participants were asked to retain lists of objects in memory. During encoding, participants had to pantomime an action to grasp (Experiments 1A & 1B) or to use the objects (Experiment 2) that was either congruent or incongruent with the objects to be retained. The results showed that performing an incongruent action impaired memory performance compared to a congruent action. This suggests that motor affordances play a role during object retention. The results are discussed in light of the embodied cognition view.     

Modulation of motor variability related to experimental muscle pain during elbow-flexion contractions

Experimental muscle pain typically reorganizes the motor control. The pain effects may decrease when the three-dimensional force components are voluntarily adjusted, but it is not known if this could have negative consequences on other structures of the motor system. The present study assessed the effects of acute pain on the force variability during sustained elbow flexion when controlling task-related (one-dimensional) and all (three-dimensional) contraction force components via visual feedback. Experimental muscle pain was induced by bolus injection of hypertonic saline into m. biceps brachii, and isotonic saline was used as control. Twelve subjects performed sustained elbow flexion at different levels of the maximal voluntary contraction (5–30% MVC) before, during, and after the injections. Three-dimensional force components were measured simultaneously with surface electromyography (EMG) from elbow flexors and auxiliary muscles. Results showed that force variability was increased during pain compared to baseline for contractions using one-dimensional feedback (P < .05), but no significant differences were found for three-dimensional feedback. During painful contractions (1) EMG activity from m. trapezius was increased during contractions using both one-dimensional and three-dimensional feedback (P < .05), and (2) the complexity of EMG from m. triceps brachii and m. deltoid was higher for the three-dimensional feedback (P < .05). In conclusion, the three-dimensional feedback reduced the pain-related functional distortion at the cost of a more complex control of synergistic muscles.     

Reorganised motor control strategies of trunk muscles due to acute low back pain

This study assessed how the low back motor control strategies were affected by experimental pain. In twelve volunteers the right m. longissimus was injected by hypertonic and isotonic (control) saline. The pain intensity was assessed on a visual analog scale (VAS). Subjects were seated on a custom-designed chair including a 3-dimensional force sensor adjusted to the segmental height of T1. Electromyography (EMG) was recorded bilaterally from longissimus, multifidus, rectus abdominis, and external oblique muscles. Isometric trunk extensions were performed before, during, and after the saline injections at 5%, 10%, and 20% of maximum voluntary contraction force. Visual feedback of the extension force was provided whereas the tangential force components were recorded. Compared with isotonic saline, VAS scores were higher following hypertonic saline injections (P < .01). Experimental low back pain reduced the EMG activity bilaterally of the rectus abdominis muscles during contractions at 10% and 20% MVC (P < .01) although force accuracy and tangential force variability was not affected. Increased variability in the tangential force composition was found during pain compared with the non-painful condition (P < .05). The immediate adaptation to pain was sufficient to maintain the quality of the task performance; however the long-term consequence of such adaptation is unknown and may overload other structures.