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We tend to mentally segment a series of events according to perceptual contextual changes, such that items from a shared context are more strongly associated in memory than items from different contexts. It is also known that timing context provides a scaffold to structure experiences in memory, but its role in event segmentation has not been investigated. We adapted a previous paradigm, which was used to investigate event segmentation using visual contexts, to study the effects of changes in timing contexts on event segmentation in associative memory. In two experiments, we presented lists of 36 items in which the interstimulus intervals (ISIs) changed after a series of six items ranging between 0.5 and 4 s in 0.5 s steps. After each list, participants judged which one of two test items were shown first (temporal order judgment) for items that were either drawn from the same context (within an ISI) or from consecutive contexts (across ISIs). Further, participants judged from memory whether the ISI associated to an item lasted longer than a standard interval (2.25 s) that was not previously shown (temporal source memory). Experiment 2 further included a time-item encoding task. Results revealed an effect of timing context changes in temporal order judgments, with faster responses (Experiment 1) or higher accuracy (Experiment 2) when items were drawn from the same context, as opposed to items drawn from across contexts. Further, in both experiments, we found that participants were well able to provide temporal source memory judgments based on recalled durations. Finally, replicated across experiments, we found subjective duration bias, as estimated by psychometric curve fitting parameters of the recalled durations, correlated negatively with within-context temporal order judgments. These findings show that changes in timing context support event segmentation in associative memory.

Brain waves, determined by electrical and magnetic brain recordings (e.g., EEG and MEG), and fluctuating behavioral responses, determined by response time or accuracy measures, are frequently taken to support discrete perception. For example, it has been proposed that humans experience only one conscious percept per brain wave (e.g., during one alpha cycle). However, the proposed link between brain waves and discrete perception is typically rather vague. More importantly, there are many models and aspects of discrete perception and it is often not apparent in what theoretical framework brain wave findings are interpreted and to what specific aspects of discrete perception they relate. Here, we review different approaches to discrete perception and highlight issues with particular interpretations. We then discuss how certain findings on brain waves may relate to certain aspects of discrete perception. The main purpose of this meta-contribution is to give a short overview of discrete models of perception and to illustrate the need to make explicit what aspects of discrete theories are addressed by what aspects of brain wave findings.

When children testify in cases of child sexual abuse (CSA), they often provide minimal responses to attorneys' questions. Thus, how attorneys ask questions may be particularly influential in shaping jurors' perceptions and memory for case details. This study examined mock jurors' perceptions after reading an excerpt of a CSA trial transcript. Participants' memory of the excerpt was tested after a two-day delay. We examined how reading a direct or cross-examination excerpt that included either high or low temporal structure impacted participants' perceptions, verdict decisions and memory reports. We found that participants who read a direct examination excerpt rated the child witness as more credible, were more likely to convict the defendant and had more accurate memory reports than those who read a cross-examination excerpt, regardless of temporal structure. Suggestions for improving jurors' comprehension and recall of child statements presented as evidence in CSA cases are discussed.

Tactile stimuli can be distinguished based on their temporal features (e.g., duration, local frequency, and number of pulses), which are fundamental for vibrotactile frequency perception. Characterizing how the hemodynamic response changes in shape across experimental conditions is important for designing and interpreting fMRI studies on tactile information processing. In this study, we focused on periodic tactile stimuli with different temporal structures and explored the hemodynamic response function (HRF) induced by these stimuli. We found that HRFs were stimulus‐dependent in tactile‐related brain areas. Continuous stimuli induced a greater area of activation and a stronger and narrower hemodynamic response than intermittent stimuli with the same duration. The magnitude of the HRF increased with increasing stimulus duration. By normalizing the characteristics into topographic matrix, nonlinearity was obvious. These results suggested that stimulation patterns and duration within a cycle may be key characters for distinguishing different stimuli. We conclude that different temporal structures of tactile stimuli induced different HRFs, which are essential for vibrotactile perception and should be considered in fMRI experimental designs and analyses., We found that HRFs were stimulus‐dependent in tactile‐related brain areas. Stimulation patterns and duration within a cycle may be key characters for distinguishing different stimuli.

Contains fulltext : 195561.pdf (Publisher’s version ) (Open Access) The aim of the current project is to enhance our understanding of cognitive creativity, specifically divergent thinking, by employing an interdisciplinary methodological approach. By integrating methodology from computational linguistics and complex systems into creativity research, the current study aims to shed light on the relationship between divergent thinking and the temporal structure of semantic associations. In complex systems, temporal structures can be described on a continuum from (i) random to (ii) flexible-stable and to (iii) persistent. Random structures are highly unpredictable, persistent structures are highly predictable, and flexible-stable structures are in-between, they are partly predictable from previous observations. Temporal structures of associations that are random (e.g., dog - graveyard - north pole) or persistent (e.g., dog - cat - rat) are hypothesized to be detrimental to divergent thinking. However, a flexible-stable structure (e.g. dog - police - drugs) is hypothesized to be related to enhanced divergent thinking (inverted-U). This notion was tested (N = 59) in a novel association chain task, combined with a frequently used measure of divergent thinking (i.e., Alternative Uses Test). Latent Semantic Analysis from computational linguistics was used to quantify the associations, and methods from complex systems in form of Power Spectral Density analysis and detrended fluctuation analysis were used to estimate the temporal structure of those associations. Although the current study does not confirm that a flexible-stable (vs. random/persistent) temporal structure of associations is related to enhanced divergent thinking skills, it hopefully challenges fellow researchers to refine the recent methodological developments for assessing the (temporal) structure of associations. Moreover, the current cross-fertilization of methodological approaches may inspire creativity researchers to take advantage of other fields' ideas and methods. To derive at a theoretically sound cognitive theory of creativity, it is important to integrate research ideas and empirical methods from a variety of disciplines. 14 p.

Insects have acquired excellent sensory information processing abilities in the process of evolution. In addition, insects have developed communication schemes based on the temporal patterns of specific sensory signals. For instance, male moths approach a female by detecting the spatiotemporal pattern of a pheromone plume released by the female. Male crickets attract a conspecific female as a mating partner using calling songs with species-specific temporal patterns. The dance communication of honeybees relies on a unique temporal pattern of vibration caused by wingbeats during the dance. Underlying these behaviors, neural circuits involving inhibitory connections play a critical common role in processing the exact timing of the signals in the primary sensory centers of the brain. Here, we discuss common mechanisms for processing the temporal patterns of sensory signals in the insect brain.

Background Females are markedly underinvestigated in the biological and behavioral sciences due to the presumption that cyclic hormonal changes across the ovulatory cycle introduce excess variability to measures of interest in comparison to males. However, recent analyses indicate that male and female mice and rats exhibit comparable variability across numerous physiological and behavioral measures, even when the stage of the estrous cycle is not considered. Hormonal changes across the ovulatory cycle likely contribute cyclic, intra-individual variability in females, but the source(s) of male variability has, to our knowledge, not been investigated. It is unclear whether male variability, like that of females, is temporally structured and, therefore, quantifiable and predictable. Finally, whether males and females exhibit variability on similar time scales has not been explored. Methods These questions were addressed by collecting chronic, high temporal resolution locomotor activity (LA) and core body temperature (CBT) data from male and female BALB/c mice. Results Contrary to expectation, males are more variable than females over the course of the day (diel variability) and exhibit higher intra-individual daily range than females in both LA and CBT. Between mice of a given sex, variability is comparable for LA but the inter-individual daily range in CBT is greater for males. To identify potential rhythmic processes contributing to these sex differences, we employed wavelet transformations across a range of periodicities (1–39 h). Conclusions Although variability in circadian power is comparable between the sexes for both LA and CBT, infradian variability is greater in females and ultradian variability is greater in males. Thus, exclusion of female mice from studies because of estrous cycle variability may increase variance in investigations where only male measures are collected over a span of several hours and limit generalization of findings from males to females.

In this study we analyzed the inter-specific relationships in assemblages of syrphids at a site in northern Italy in order to determine whether there are patterns in diurnal co-occurrence. We adopted a null model approach and calculated two co-occurrence metrics, the C-score and variance ratio (V-ratio), both for the total catch and of the morning (8:00-13:00) and afternoon (13:00-18:00) catches separately, and for males and females. We recorded discordant species richness, abundance and co-occurrence patterns in the samples collected. Higher species richness and abundance were recorded in the morning, when the assemblage had an aggregated structure, which agrees with previous findings on communities of invertebrate primary consumers. A segregated pattern of co-occurrence was recorded in the afternoon, when fewer species and individuals were collected. The pattern recorded is likely to be caused by a number of factors, such as a greater availability of food in the morning, prevalence of hot and dry conditions in the early afternoon, which are unfavourable for hoverflies, and possibly competition with other pollinators. Our results indicate that restricting community studies to a particular time of day will result in certain species and/or species interactions not being recorded.

Temporal regularities in speech, such as interdependencies in the timing of speech events, are thought to scaffold early acquisition of the building blocks in speech. By providing on-line clues to the location and duration of upcoming syllables, temporal structure may aid segmentation and clustering of continuous speech into separable units. This hypothesis tacitly assumes that learners exploit predictability in the temporal structure of speech. Existing measures of speech timing tend to focus on first-order regularities among adjacent units, and are overly sensitive to idiosyncrasies in the data they describe. Here, we compare several statistical methods on a sample of 18 languages, testing whether syllable occurrence is predictable over time. Rather than looking for differences between languages, we aim to find across languages (using clearly defined acoustic, rather than orthographic, measures), temporal predictability in the speech signal which could be exploited by a language learner. First, we analyse distributional regularities using two novel techniques: a Bayesian ideal learner analysis, and a simple distributional measure. Second, we model higher-order temporal structure—regularities arising in an ordered series of syllable timings—testing the hypothesis that non-adjacent temporal structures may explain the gap between subjectively-perceived temporal regularities, and the absence of universally-accepted lower-order objective measures. Together, our analyses provide limited evidence for predictability at different time scales, though higher-order predictability is difficult to reliably infer. We conclude that temporal predictability in speech may well arise from a combination of individually weak perceptual cues at multiple structural levels, but is challenging to pinpoint.

Recent studies of brain plasticity that pertain to time perception have shown that fast training of temporal discrimination in one modality, for example, the auditory modality, can improve performance of temporal discrimination in another modality, such as the visual modality. We here examined whether the perception of visual Ternus motion could be recalibrated through fast crossmodal statistical binding of temporal information and stimuli properties binding. We conducted two experiments, composed of three sessions each: pre-test, learning, and post-test. In both the pre-test and the post-test, participants classified the Ternus display as either “element motion” or “group motion.” For the training session in Experiment 1, we constructed two types of temporal structures, in which two consecutively presented sound beeps were dominantly (80%) flanked by one leading visual Ternus frame and by one lagging visual Ternus frame (VAAV) or dominantly inserted by two Ternus visual frames (AVVA). Participants were required to respond which interval (auditory vs. visual) was longer. In Experiment 2, we presented only a single auditory–visual pair but with similar temporal configurations as in Experiment 1, and asked participants to perform an audio–visual temporal order judgment. The results of these two experiments support that statistical binding of temporal information and stimuli properties can quickly and selectively recalibrate the sensitivity of perceiving visual motion, according to the protocols of the specific bindings.

Temporal information promotes visual grouping of local image features into global spatial form. However, experiments demonstrating time-based grouping typically confound two potential sources of information: temporal synchrony (precise timing of changes) and temporal structure (pattern of changes over time). Here, we show that observers prefer temporal structure for determining perceptual organization. That is, human vision groups elements that change according to the same global pattern, even if the changes themselves are not synchronous. This finding prompts an important, testable prediction concerning the neural mechanisms of binding: patterns of neural spiking over time may be more important than absolute spike synchrony.

A modified version of the ‘path finder’ display consisting of many small oriented Gabor patches was used to study the joint contributions of spatial and temporal structures to shape perception. A two-interval forced-choice procedure measured detectability of curved ‘paths’ defined by orientation (‘good continuation’) and/or by temporal synchrony of change in motion direction (‘common fate’). When orientation was completely random (no spatial ‘path’ cue) temporal synchrony still supported reliable performance, but only when correlation of change among ‘path’ elements was high. When combined, these two weak spatial and temporal structures yielded performance in excess of probability summation: ‘paths’ weakly defined by orientation were highly conspicuous when the constituent Gabors underwent synchronized changes in direction of motion, even though the individual directions of path elements were uncorrelated. Spatial grouping from temporal structure may arise from correlated transients associated with synchronized changes in motion direction. Evidently these two mechanisms for promotion of spatial grouping interact synergistically.

Observers can more easily detect correlated patterns of temporal contrast modulation within hybrid visual images composed of two components when those components are drawn from the same original picture (Blake, R., & Yang, Y. (1997). Proceedings of the National Academy of Science, 94, 7115–7119). To learn whether spatial phase is a mediating variable, we measured thresholds for detection of contrast modulation over time among component gratings while manipulating spatial phase among those components. In Experiment 1, observers more easily detected correlated contrast modulation when two component gratings were aligned in peaks-subtract phase. Experiment 2 showed that this phase-dependent detectability of synchronized contrast modulation is mediated by the phase-dependent, non-linear interaction among spatial frequency channels. The rigorous evaluation of several a priori reasonable hypotheses indicates that the phase-dependent detectability is not based on local spatial features such as local luminance, contrast or luminance gradient. Taken together, our results indicate that the spatial phase relationship and the temporal correlation of contrast modulation of two component gratings are both important for triggering facilitatory interaction between neural analyzers tuned to those gratings.

This review paper deals with methodological and technical foundations of the Operational Architectonics framework of brain and mind functioning. This theory provides a framework for mapping and understanding important aspects of the brain mechanisms that constitute perception, cognition, and eventually consciousness. The methods utilized within Operational Architectonics framework allow analyzing with an incredible detail the operational behavior of local neuronal assemblies and their joint activity in the form of unified and metastable operational modules, which constitute the whole hierarchy of brain operations, operations of cognition and phenomenal consciousness.

In dynamic visual environments, objects can differ from their backgrounds in terms of their associated temporal structure—the time course of changes in some stimulus property defining object and background. In a series of experiments, we investigated whether different “messengers” of temporal structure group into coherent spatial forms. Observers viewed arrays of Gabor patches in which different temporal structures designated figure and ground regions; extracting the figure required grouping across synchronized orientation, spatial frequency, phase, and/or contrast changes. Observers were able to extract spatial form from temporal structure even when information had to be combined across different messengers. Further, mixing messengers of temporal structure proved cost-free: task performance when grouping across messengers approximated performance when all information resided within a single messenger. Thus, the visual system can abstract temporal structure regardless of the messenger of the dynamic event; a coherent spatial structure emerges from this abstracted temporal structure.

Contrasting with the distinct psychological sense of time in humans, physiological correlates underlying this impression are not readily observable. Classical motor structures such as the cerebellum and the basal ganglia are among the prime candidates for the neural implementation of dedicated temporal processing mechanisms, specialized in generating representations of the temporal structure of events. Consequently, circumscribed structural damage to these brain areas is expected to alter the use of temporal structure in motor and non-motor behavior. A crucial aspect of this general capacity is temporal extrapolation, i.e., the ability to use the temporal structure of past events to predict when a future event will happen and to adapt behavior accordingly. Such predictive adaptation to temporal structure provides the opportunity to optimize behavior on the basis of perceived regularity in temporal structure. Against this background, a series of experiments was conducted, taking advantage of the high spatial resolution of structural magnetic resonance imaging and the high temporal resolution of event-related potentials of the electroencephalogram. Patients with focal lesions of either the cerebellum or the basal ganglia and matched controls performed tasks, which require precise production and/or perception of temporal structure. Production of temporal structure was tested in the context of sensorimotor synchronization with auditory pacing sequences containing a tempo change. Measures of interest related to the general efficiency of the tapping performance, to error correction in response to the tempo change, as well as to the awareness of the change. Perception was tested in the context of auditory deviance processing as a function of temporal predictability, i.e., by means of “oddball sequences”, consisting of tones that were presented with regular or irregular temporal structure. Measures of interest related to qualitative differences in early and later stages of deviance processing, as indexed by event-related potentials (P50, P300). In comparison to controls, the performance of the patients diverges systematically on several of these measures, suggesting impaired use of temporal structure. Taken together, the results differentiate the specific contributions of the cerebellum and the basal ganglia to the processing of temporal structure, most likely within an integrative dedicated temporal processing network.