Lesions in the anterior thalamic nuclei of rats do not disrupt acquisition of stimulus sequence learning

Four experiments examined the effects of encoding multiple standards in a temporal generalization task in the visual and auditory modalities both singly and cross-modally, using stimulus durations ranging, across different experiments, from 100 to 1,400 ms. Previous work has shown that encoding and storing multiple auditory standards of different durations resulted in systematic interference with the memory of the standard, characterized by a shift in the location of peak responding, and this result, from Ogden, Wearden, and Jones (2008), was replicated in the present Experiment 1. Experiment 2 employed the basic procedure of Ogden et al. using visual stimuli and found that encoding multiple visual standards did not lead to performance deterioration or any evidence of systematic interference between the standards. Experiments 3 and 4 examined potential cross-modal interference. When two standards of different modalities and durations were encoded and stored together there was also no evidence of interference between the two. Taken together, these results, and those of Ogden et al., suggest that, in humans, visual temporal reference memory may be more permanent than auditory reference memory and that auditory temporal information and visual temporal information do not mutually interfere in reference memory.     

Retrieval dynamics in self-terminated memory search

Attended stimuli are perceived as occurring earlier than unattended stimuli. This phenomenon of prior entry is usually identified by a shift in the point of subjective simultaneity (PSS) in temporal order judgements (TOJs). According to its traditional psychophysical interpretation, the PSS coincides with the perception of simultaneity. This assumption is, however, questionable. Technically, the PSS represents the temporal interval between two stimuli at which the two alternative TOJs are equally likely. Thus it also seems possible that observers perceive not simultaneity, but uncertainty of temporal order. This possibility is supported by prior-entry studies, which find that perception of simultaneity is not very likely at the PSS. The present study tested the percept at the PSS in prior entry, using peripheral cues to orient attention. We found that manipulating attention caused varying temporal perceptions around the PSS. On some occasions observers perceived the two stimuli as simultaneous, but on others they were simply uncertain about the order in which they had been presented. This finding contradicts the implicit assumption of most models of temporal order perception, that perception of simultaneity inevitably results if temporal order cannot be discriminated.     

Does temporal contiguity moderate contingency learning in a speeded performance task?

In four experiments, we varied the time between the onset of distracting nonwords and target colour words in a word–word version of the colour–word contingency learning paradigm. Contingencies were created by pairing a distractor nonword more often with one target colour word than with other colour words. A contingency effect corresponds to faster responses to the target colour word on high-contingency trials (i.e., distractor nonword followed by the target colour word with which it appears most often) than on low-contingency trials (i.e., distractor nonword followed by a target colour word with which it appears only occasionally). Roughly equivalent-sized contingency effects were found at stimulus-onset asynchronies (SOAs) of 50, 250, and 450 ms in Experiment 1, and 50, 500, and 1,000 ms in Experiment 2. In Experiment 3, a contingency effect was observed at SOAs of –50, –200, and –350 ms. In Experiment 4, interstimulus interval (ISI) was varied along with SOA, and learning was equivalent for 200-, 700-, and 1,200-ms SOAs. Together, these experiments suggest that the distracting stimulus does not need to be presented in close temporal contiguity with the response to induce learning. Relations to past research on causal judgement and implications for further contingency learning research are discussed.     

Timing is everything: Changes in presentation rate have opposite effects on auditory and visual implicit statistical learning

Implicit statistical learning (ISL) is exclusive to neither a particular sensory modality nor a single domain of processing. Even so, differences in perceptual processing may substantially affect learning across modalities. In three experiments, statistically equivalent auditory and visual familiarizations were presented under different timing conditions that either facilitated or disrupted temporal processing (fast or slow presentation rates). We find an interaction of rate and modality of presentation: At fast rates, auditory ISL was superior to visual. However, at slow presentation rates, the opposite pattern of results was found: Visual ISL was superior to auditory. Thus, we find that changes to presentation rate differentially affect ISL across sensory modalities. Additional experiments confirmed that this modality-specific effect was not due to cross-modal interference or attentional manipulations. These findings suggest that ISL is rooted in modality-specific, perceptually based processes.     

The relativity of time perception produced by facial emotion stimuli

Insults elicit intense emotion. This study tests the hypothesis that one's social image, which is especially salient in honour cultures, influences the way in which one reacts to an insult. Seventy-seven honour-oriented and 72 non-honour oriented participants answered questions about a recent insult episode. Participants experienced both anger and shame in reaction to the insult. However, these emotions resulted in different behaviours. Anger led to verbal attack (i.e., criticising, insulting in return) among all participants. This relationship was explained by participants’ motivation to punish the wrongdoer. Shame, on the other hand, was moderated by honour. Shame led to verbal disapproval of the wrongdoers behaviour, but only among the honour-oriented participants. This relationship was explained by these participants’ motivation to protect their social image. By contrast, shame led to withdrawal among non-honour-oriented participants.     

Emotional facial expressions and the attentional blink: Attenuated blink for angry and happy faces irrespective of social anxiety

Although facial information is distributed over spatial as well as temporal domains, thus far research on selective attention to disapproving faces has concentrated predominantly on the spatial domain. This study examined the temporal characteristics of visual attention towards facial expressions by presenting a Rapid Serial Visual Presentation (RSVP) paradigm to high (n=33) and low (n=34) socially anxious women. Neutral letter stimuli (p, q, d, b) were presented as the first target (T1), and emotional faces (neutral, happy, angry) as the second target (T2). Irrespective of social anxiety, the attentional blink was attenuated for emotional faces. Emotional faces as T2 did not influence identification accuracy of a preceding (neutral) target. The relatively low threshold for the (explicit) identification of emotional expressions is consistent with the view that emotional facial expressions are processed relatively efficiently.     

Time perception in severe traumatic brain injury patients: A study comparing different methodologies

In this study, we investigated time perception in patients with traumatic brain injury (TBI). Fifteen TBI patients and 15 matched healthy controls participated in the study. Participants were tested with durations above and below 1 s on three different temporal tasks that involved time reproduction, production, and discrimination tasks. Data variables analyzed included amount of errors, relative errors, and coefficient of variation. Both groups completed a neuropsychological battery that included measures of attention, working memory, and executive functions. Results revealed significant differences between groups on the time reproduction and discrimination tasks, whereas groups showed similar performance on the time production task. Correlation analyses showed involvement of attention, working memory and executive functions on the time reproduction and time discrimination tasks, but there was no involvement on the time production task. These findings suggest that TBI does not impact specific temporal function. Rather, impairments in attention, working memory and executive function abilities may explain lower temporal performance in people with TBI.     

Community-based Research and Technoscience Activism: A Report on the Living Knowledge 3 Conference

New medical imaging technologies enable the production of photos of human cells that are magnified to make them visible to the eye. Such cellular images have gained aesthetic as well as dramatic appeal, as they have moved out of the laboratories and become available for the public. At this stage, they are refashioned to reveal matters more clearly and pedagogically. Organic matter that might be confusing to the audience is removed and colours added to distinguish various aspects—but despite such manipulations, the result appears as images of real human cells, making them different from drawings and models. One example of this is the website of a Norwegian governmental organization for information on biotechnology and bioethics which displays images of egg and sperm cells related to techniques of assisted reproduction. These images represent cells as autonomous and independent of human gendered bodies. The process whereby cells culturally become detached and disassociated from human bodies is here referred to as a process of entification whereby the cells reappear as detachable, usable entities.     

No time for powers

In this paper, I will investigate the compatibility of different metaphysics of time with the powers view. At first sight, it seems natural to combine some sort of powers ontology with a dynamical view of time, since the dynamic character of powers appears to account for the progression of time. Accordingly, it has been argued that a powers ontology, which is supposed to be inherently dynamic and productive, is incompatible with eternalism, which does not allow for any sort of real productivity. After having reviewed these arguments, I will argue that the powers view is not only incompatible with eternalism but also with the moving spotlight view and growing block theory. I will go on to argue that the specific notion of activity that the powers ontology provides is not straightforwardly compatible with presentism either.     

Time processing in children with Tourette’s syndrome

Background

Tourette syndrome (TS) is characterized by dysfunctional connectivity between prefrontal cortex and sub-cortical structures, and altered meso-cortical and/or meso-striatal dopamine release. Since time processing is also regulated by fronto-striatal circuits and modulated by dopaminergic transmission, we hypothesized that time processing is abnormal in TS.

Methods

We compared time processing abilities between nine children with TS-only (i.e. without major psychiatric comorbidities) and 10 age-matched healthy children, employing a time reproduction task in which subjects actively reproduce different temporal intervals, and a time comparison task in which subjects judge whether a test interval is longer or shorter than a reference interval. IQ, sustained and divided attention, and working memory were assessed in both groups using the Leiter International Performance Scale-Revised, and the Digit Span sub-test of the WISC-R.

Results

Children with TS-only reproduced in an overestimated fashion over-second, but not sub-second, time intervals. The precision of over-second intervals reproduction correlated with tic severity, in that the lower the tic severity, the closer the reproduction of over-second time intervals to their real duration. Time reproduction performance did not significantly correlate with IQ, attention and working memory measures in both groups. No differences between groups were documented in the time comparison task.

Conclusions

The improvement of time processing in children with TS-only seems specific for the over-second range of intervals, consistent with an enhancement in the ‘cognitively controlled’ timing system, which mainly processes longer duration intervals, and depends upon dysfunctional connectivity between the basal ganglia and the dorso-lateral prefrontal cortex. The absence of between-group differences on time comparison, moreover, suggests that TS patients manifest a selective improvement of ‘motor’ timing abilities, rather than of perceptual time abilities. Our data also support an enhancement of cognitive control processes in TS children, probably facilitated by effortful tic suppression.