Distinct brain dynamics and networks for processing short and long auditory time intervals.

Psychophysical studies suggest that time intervals above and below 1.2 s are processed differently in the human brain. However, the neural underpinnings of this dissociation remain unclear. Here, we investigate whether distinct or common brain networks and dynamics support the passive perception of short (below 1.2 s) and long (above 1.2 s) empty time intervals. Twenty participants underwent an EEG recording during an auditory oddball paradigm with .8- and 1.6-s standard time intervals and deviant intervals either shorter (early) or longer (delayed) than the standard interval. We computed the auditory ERPs for each condition at the sensor and source levels. We then performed whole brain cluster-based permutation statistics for the CNV, N1 and P2, components, testing deviants against standards. A CNV was found only for above 1.2 s intervals (delayed deviants), with generators in temporo-parietal, SMA, and motor regions. Deviance detection of above 1.2 s intervals occurred during the N1 period over fronto-central sensors for delayed deviants only, with generators in parietal and motor regions. Deviance detection of below 1.2 s intervals occurred during the P2 period over fronto-central sensors for delayed deviants only, with generators in primary auditory cortex, SMA, IFG, cingulate and parietal cortex. We then identified deviance related changes in directed connectivity using bivariate Granger causality to highlight the networks dynamics associated with interval processing above and below 1.2. These results suggest that distinct brain dynamics and networks support the perception of time intervals above and below 1.2 s.

Temporal perception in closed-skill sports: An experimental study on expert swimmers and runners.

The cognitive benefits of closed-skill sports practice have so far been scantily investigated. Here, we thus focused on the potential impact of swimming and running - two sports that highly rely on a precise control of timing - on time processing. To investigate the impact of these closed-skill sports on time perception and estimation, three groups of participants (for a total of eighty-four young adults) took part in the present study: expert swimmers, expert runners, and non-athletes. The ability to process temporal information in the milliseconds and seconds range was assessed through a time reproduction and a finger-tapping tasks, while a motor imagery paradigm was adopted to assess temporal estimation of sport performance in a wider interval range. We also employed the Vividness of Movement Imagery Questionnaire to assess the individual's ability of motor imagery. Results showed that closed-skill sports, specifically time-related disciplines, enhance motor imagery and time perception abilities. Swimmers were more accurate and consistent in perceiving time when compared to runners, probably thanks to the sensory muffled environment that leads these athletes to be more focused on the perception of their internal rhythm.

Subjective time perception in musical imagery: An fMRI study on musicians.

The cognitive preparation of an operation without overt motor execution is referred to as imagery (of any kind). Over the last two decades of progress in brain timing studies, the timing of imagery has received little focus. This study compared the time perception of ten professional violinists' actual and imagery performances to see if such an analysis could offer a different model of timing in musicians' imagery skills. When comparing the timing profiles of the musicians between the two situations (actual and imagery), we found a significant correlation in overestimation of time in the imagery. In our fMRI analysis, we found high activation in the left cerebellum. This finding seems consistent with dedicated models of timing such as the cerebellar timing hypothesis, which assigns a "specialized clock" for tasks. In addition, the present findings might provide empirical data concerning imagery, creativity, and time. Maintaining imagery over time is one of the foundations of creativity, and understanding the underlying temporal neuronal mechanism might help us to apprehend the machinery of creativity per se.

Motion-Binding Property Contributes to Accurate Temporal-Order Perception in Audiovisual Synchrony.

Temporal perception in multisensory processing is important for an accurate and efficient understanding of the physical world. In general, it is executed in a dynamic environment in our daily lives. In particular, the motion-binding property is important for correctly identifying moving objects in the external environment. However, how this property affects multisensory temporal perception remains unclear. We investigate whether the motion-binding property influences audiovisual temporal integration. The study subjects performed four types of temporal-order judgment (TOJ) task experiments using three types of perception. In Experiment 1, the subjects conducted audiovisual TOJ tasks in the motion-binding condition, between two flashes, and in the simultaneous condition, in which the two flashes are perceived as simultaneous stimuli without motion. In Experiment 2, subjects conducted audiovisual TOJ tasks in the motion-binding condition and the short and long successive interval condition, in which the two stimuli are perceived as successive with no motion. The results revealed that the point of subjective simultaneity (PSS) and the just-noticeable difference (JND) in the motion-binding condition differed significantly from those in the simultaneous and short and long successive interval conditions. Specifically, the PSS in the motion-binding condition was shifted toward a sound-lead stimulus in which the PSS became closer to zero (i.e., physical simultaneity) and the JND became narrower compared to other conditions. This suggests that the motion-binding property contributes to accurate temporal integration in multisensory processing by precisely encoding the temporal order of the physical stimuli.

Neural substrates of top-down processing during perceptual duration-based timing and beat-based timing.

Temporal context is a crucial factor in timing. Previous studies have revealed that the timing of regular stimuli, such as isochronous beats or rhythmic sequences (termed beat-based timing), activated the basal ganglia, whereas the timing of single intervals or irregular stimuli (termed duration-based timing) activated the cerebellum. We conducted a functional magnetic resonance imaging (fMRI) experiment to determine whether top-down processing of perceptual duration-based and beat-based timings affected brain activation patterns. Our participants listened to auditory sequences containing both single intervals and isochronous beats and judged either the duration of the intervals or the tempo of the beats. Whole-brain analysis revealed that both duration judgments and tempo judgments activated similar areas, including the basal ganglia and cerebellum, with no significant difference in the activated regions between the two conditions. In addition, an analysis of the regions of interest revealed no significant differences between the activation levels measured for the two tasks in the basal ganglia as well as the cerebellum. These results suggested that a set of common brain areas were involved in top-down processing of both duration judgments and tempo judgments. Our findings indicate that perceptual duration-based timing and beat-based timing are driven by stimulus regularity irrespective of top-down processing.

Mechanism of the compression effect on visual duration perception caused by temporally sandwiching sounds.

When task-irrelevant nontarget sound temporally sandwiches brief target visual stimuli, its perceived duration is compressed (time compression). Since little is known about the mechanisms of time compression, this study examined its causal factors. Experiment 1 measured the effects of preceding, trailing, and sandwiching sounds on visual duration perception and examined whether adding the first two effects predicts the empirical effect of the third. The time compression occurred only when the target visual stimulus was 300 ms, but not for a target duration ≥500 ms. However, the predicted additive effect did not match the time compression. Experiment 2 examined the weighted integration of unisensory estimates (visual filled interval and auditory empty interval) by measuring the perceived duration of unimodal and multimodal stimuli. The predicted duration by weighted integration fitted the time compression occurring at the target duration of 300 ms. However, when the target was 500 ms or longer, no time compression occurred and the predicted durations were longer than the empirical durations. These results suggest that the visual system with weak temporal resolution integrated more accurate and reliable temporal information, rather than additive effect, resulting in time compression only when the target duration was too short. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Future time perspective and academic procrastination among nursing students: The mediating role of mindfulness.

AIM: To explore the relationship between university nursing students' academic procrastination, mindfulness, and future time perspective. DESIGN: A cross-sectional study. METHODS: A total of 343 university nursing students recruited from eight provinces in China have reported procrastination characteristics through fulfilling an online website link. The main instruments involved Mindfulness Attention Awareness Scale (MAAS), Zimbardo Time Perspective Scale, and Procrastination Assessment Scale (PASS). RESULTS: Participants who self-assessed higher frequency and degree of academic procrastination tended to possess lower future time consciousness, and lower mindfulness. Mindfulness served as a mediation effect between future time perspective and academic procrastination. The study indicates that weakening an individual's procrastination can be alleviated through future time awareness and mindfulness. Concentrating on influencing factors, strengthening nursing student's future time perspective, and practicing mindfulness training could assist educators to decrease students' procrastination intentions and behaviours.

Change in Time Perception Following the Place of Pre-Existence Technique.

Time perception is closely related to spatial and bodily perception, yet little is known about how this interrelationship is impacted by meditation and biological sex. To examine this, we studied the effects of a stepwise application of three meditation techniques, from focused attention, to open monitoring to non-dual meditation, encompassed in the Place of Pre-Existence technique (PPEt) on the subjective perception of time, space and body using a pre-post research design. A total of 280 participants (mean age = 47.09 years; SD = 10.13; 127:153 males to females) completed the Subjective Time, Self, Space inventory before and after PPEt. Following PPEt, participants perceived time passing as slowing down, while time intensity, relaxation, 'awareness of space' and 'awareness of body' increased, suggesting heightened mindfulness to these constructs following the training. Awareness of space revealed to be modulated by biological sex and meditation expertise, with males showing a decrease of spatial awareness as a function of meditation expertise while females showed an opposite pattern. The speed and intensity of the experience of time both correlated with body and space awareness. In line with previous studies demonstrating a connection between relaxation and perception of time, a significant correlation was found between relaxation and the subjective experience of the intensity of time. The current results are discussed in the context of the embodied experience of time, and the Sphere Model of Consciousness.

An RCT study showing few weeks of music lessons enhance audio-visual temporal processing.

Music involves different senses and is emotional in nature, and musicians show enhanced detection of audio-visual temporal discrepancies and emotion recognition compared to non-musicians. However, whether musical training produces these enhanced abilities or if they are innate within musicians remains unclear. Thirty-one adult participants were randomly assigned to a music training, music listening, or control group who all completed a one-hour session per week for 11 weeks. The music training group received piano training, the music listening group listened to the same music, and the control group did their homework. Measures of audio-visual temporal discrepancy, facial expression recognition, autistic traits, depression, anxiety, stress and mood were completed and compared from the beginning to end of training. ANOVA results revealed that only the music training group showed a significant improvement in detection of audio-visual temporal discrepancies compared to the other groups for both stimuli (flash-beep and face-voice). However, music training did not improve emotion recognition from facial expressions compared to the control group, while it did reduce the levels of depression, stress and anxiety compared to baseline. This RCT study provides the first evidence of a causal effect of music training on improved audio-visual perception that goes beyond the music domain.

Sensory Target Detection at Local and Global Timescales Reveals a Hierarchy of Supramodal Dynamics in the Human Cortex.

To ensure survival in a dynamic environment, the human neocortex monitors input streams from different sensory organs for important sensory events. Which principles govern whether different senses share common or modality-specific brain networks for sensory target detection? We examined whether complex targets evoke sustained supramodal activity while simple targets rely on modality-specific networks with short-lived supramodal contributions. In a series of hierarchical multisensory target detection studies (n = 77, of either sex) using EEG, we applied a temporal cross-decoding approach to dissociate supramodal and modality-specific cortical dynamics elicited by rule-based global and feature-based local sensory deviations within and between the visual, somatosensory, and auditory modality. Our data show that each sense implements a cortical hierarchy orchestrating supramodal target detection responses, which operate at local and global timescales in successive processing stages. Across different sensory modalities, simple feature-based sensory deviations presented in temporal vicinity to a monotonous input stream triggered a mismatch negativity-like local signal which decayed quickly and early, whereas complex rule-based targets tracked across time evoked a P3b-like global neural response which generalized across a late time window. Converging results from temporal cross-modality decoding analyses across different datasets, we reveal that global neural responses are sustained in a supramodal higher-order network, whereas local neural responses canonically thought to rely on modality-specific regions evolve into short-lived supramodal activity. Together, our findings demonstrate that cortical organization largely follows a gradient in which short-lived modality-specific as well as supramodal processes dominate local responses, whereas higher-order processes encode temporally extended abstract supramodal information fed forward from modality-specific cortices.SIGNIFICANCE STATEMENT Each sense supports a cortical hierarchy of processes tracking deviant sensory events at multiple timescales. Conflicting evidence produced a lively debate around which of these processes are supramodal. Here, we manipulated the temporal complexity of auditory, tactile, and visual targets to determine whether cortical local and global ERP responses to sensory targets share cortical dynamics between the senses. Using temporal cross-decoding, we found that temporally complex targets elicit a supramodal sustained response. Conversely, local responses to temporally confined targets typically considered modality-specific rely on early short-lived supramodal activation. Our finding provides evidence for a supramodal gradient supporting sensory target detection in the cortex, with implications for multiple fields in which these responses are studied (e.g., predictive coding, consciousness, and attention).

Temporal auditory processing in people exposed to musical instrument practice. / Processamento auditivo temporal em indivíduos expostos à prática musical instrumental.

PURPOSE: To investigate the influence of musical instrument practice on temporal auditory abilities and on the results of cortical potentials related to auditory events (P300) in a group of young musicians compared to individuals without experience in musical practice. METHODS: This is a prospective cross-sectional observational study. In total, 34 individuals between 18 and 30 years old, of both sexes, took part and were divided in two groups: Group I (GI), composed of musicians (n=16), and Group II (GII), composed of non-musicians (n=18). All participants underwent behavioral evaluation of temporal auditory processing, composed of Duration Pattern Sequence Test (DPS), Pitch Pattern Sequence Test (PPS), Random Gap Detection Test (RGDT) and electrophysiological evaluation - Long Latency Auditory Evoked Potential - P300. GI also answered a specific questionnaire to characterize musical practice. RESULTS: We observed statistically significant differences with superior performance of GI compared with GII in all behavioral tests (p<0.001*). The groups' performance was similar regarding the latency and amplitude parameters analyzed from LLAEP-300 data (p>0.05). CONCLUSION: The findings show a positive influence of musical practice toward the improvement of auditory abilities of temporal ordering and resolution. All participants presented adequate cortical functioning of the central auditory nervous system, without significant differences between musicians and non-musicians when considering P300 amplitude and latency.

OBJETIVO: Investigar a influência da prática musical instrumental nas habilidades auditivas temporais e nos resultados de potenciais corticais relacionados a eventos auditivos (P300) em um grupo de jovens músicos em comparação com indivíduos sem experiência prática musical. MÉTODO: Trata-se de um estudo prospectivo, observacional, analítico e transversal. Participaram 34 indivíduos entre 18 a 30 anos, de ambos os sexos, divididos em dois grupos: Grupo I (GI), composto por indivíduos músicos (n=16) e Grupo II (GII), composto por indivíduos não músicos (n=18). Todos os participantes realizaram avaliação comportamental do processamento auditivo temporal, composta pelos testes de Padrão de Duração (TPD), Padrão de Frequência (TPF), Random Gap Detection (RGDT) e avaliação eletrofisiológica - Potencial Evocado Auditivo de Longa Latência (PEALL) - P300. O GI respondeu também a um questionário específico para caracterização da prática musical. RESULTADOS: Foram observadas diferenças estatisticamente significantes com desempenho superior do GI em relação ao GII em todos os testes comportamentais aplicados (p<0,001*). Não foram encontradas diferenças significantes entre os grupos com relação aos parâmetros de latência e amplitude analisados a partir da obtenção do PEALL-300 (p>0,05). CONCLUSÃO: Os achados demonstraram influência positiva da prática musical em relação ao aprimoramento de habilidades auditivas de ordenação e resolução temporal. Todos os participantes apresentaram adequado funcionamento cortical do sistema nervoso auditivo central, sem diferenças significantes entre músicos e não músicos nos parâmetros de amplitude e latência do P300.

Training the brain to time: the effect of neurofeedback of SMR-Beta1 rhythm on time perception in healthy adults.

The timing ability plays an important role in everyday activities and is influenced by several factors such as the attention and arousal levels of the individuals. The effects of these factors on time perception have been interpreted through psychological models of time, including Attentional Gate Model (AGM). On the other hand, research has indicated that neurofeedback (NFB) training improves attention and increases arousal levels in the clinical and healthy population. Regarding the link between attentional processing and arousal levels and NFB and their relation to time perception, this study is a pilot demonstration of the influence of SMR-Beta1 (12-18 Hz) NFB training on time production and reproduction performance in healthy adults. To this end, 12 (9 female and 3 males; M = 26.3, SD = 3.8) and 12 participants (7 female and 5 males; M = 26.9, SD = 3.1) were randomly assigned into the experimental (with SMR-Beta1 NFB) and control groups (without any NFB training), respectively. The experimental group underwent intensive 10 sessions (3 days a week) of the 12-18 Hz up-training. Time production and reproduction performance were assessed pre and post NFB training for all participants. Three-way mixed ANOVA was carried out on T-corrected scores of reproduction and production tasks. Correlation analysis was also performed between SMR-Beta1 and time perception. While NFB training significantly influenced time production (P < 0.01), no such effect was observed for the time reproduction task. The results of the study are finally discussed within the frameworks of AGM, dual-process and cognitive aspects of time perception. Overall, our results contribute to disentangling the underlying mechanisms of temporal performance in healthy individuals.

When long appears short: Effects of auditory distraction on event-related potential correlates of time perception.

Attentional models of time perception assume that the perceived duration of a stimulus depends on the extent to which attentional resources are allocated to its temporal information. Here, we studied the effects of auditory distraction on time perception, using a combined attentional-distraction duration-discrimination paradigm. Participants were confronted with a random sequence of long and short tone stimuli, most of which having a uniform (standard) pitch and only a few a different (deviant) pitch. As observed in previous studies, pitch-deviant tones impaired the discrimination of tone duration and triggered a sequence of event-related potentials (ERPs) reflecting a cycle of deviance detection, involuntary attentional distraction and reorientation (MMN, P3a, RON). Contrasting ERPs of short and long tone durations revealed that long tones elicited a more pronounced fronto-central contingent negative variation (CNV) in the time interval after the expected offset of the short tone as well as a more prominent centro-parietal late positive complex (LPC). Relative to standard-pitch tones, deviant-pitch tones especially impaired the correct discrimination of long tones, which was associated with a reduction of the CNV and LPC. These results are interpreted within the theoretical framework of resource-based models of time perception, in which involuntary distraction due to a deviant event led to a withdrawal of attentional resources from the processing of time information.

How Do You Feel the Rhythm: Dynamic Motor-Auditory Interactions Are Involved in the Imagination of Hierarchical Timing.

Predicting and organizing patterns of events is important for humans to survive in a dynamically changing world. The motor system has been proposed to be actively, and necessarily, engaged in not only the production but the perception of rhythm by organizing hierarchical timing that influences auditory responses. It is not yet well understood how the motor system interacts with the auditory system to perceive and maintain hierarchical structure in time. This study investigated the dynamic interaction between auditory and motor functional sources during the perception and imagination of musical meters. We pursued this using a novel method combining high-density EEG, EMG, and motion capture with independent component analysis to separate motor and auditory activity during meter imagery while robustly controlling against covert movement. We demonstrated that endogenous brain activity in both auditory and motor functional sources reflects the imagination of binary and ternary meters in the absence of corresponding acoustic cues or overt movement at the meter rate. We found clear evidence for hypothesized motor-to-auditory information flow at the beat rate in all conditions, suggesting a role for top-down influence of the motor system on auditory processing of beat-based rhythms, and reflecting an auditory-motor system with tight reciprocal informational coupling. These findings align with and further extend a set of motor hypotheses from beat perception to hierarchical meter imagination, adding supporting evidence to active engagement of the motor system in auditory processing, which may more broadly speak to the neural mechanisms of temporal processing in other human cognitive functions.SIGNIFICANCE STATEMENT Humans live in a world full of hierarchically structured temporal information, the accurate perception of which is essential for understanding speech and music. Music provides a window into the brain mechanisms of time perception, enabling us to examine how the brain groups musical beats into, for example a march or waltz. Using a novel paradigm combining measurement of electrical brain activity with data-driven analysis, this study directly investigates motor-auditory connectivity during meter imagination. Findings highlight the importance of the motor system in the active imagination of meter. This study sheds new light on a fundamental form of perception by demonstrating how auditory-motor interaction may support hierarchical timing processing, which may have clinical implications for speech and motor rehabilitation.

Towards understanding how we pay attention in naturalistic visual search settings.

Research on attentional control has largely focused on single senses and the importance of behavioural goals in controlling attention. However, everyday situations are multisensory and contain regularities, both likely influencing attention. We investigated how visual attentional capture is simultaneously impacted by top-down goals, the multisensory nature of stimuli, and the contextual factors of stimuli's semantic relationship and temporal predictability. Participants performed a multisensory version of the Folk et al. (1992) spatial cueing paradigm, searching for a target of a predefined colour (e.g. a red bar) within an array preceded by a distractor. We manipulated: 1) stimuli's goal-relevance via distractor's colour (matching vs. mismatching the target), 2) stimuli's multisensory nature (colour distractors appearing alone vs. with tones), 3) the relationship between the distractor sound and colour (arbitrary vs. semantically congruent) and 4) the temporal predictability of distractor onset. Reaction-time spatial cueing served as a behavioural measure of attentional selection. We also recorded 129-channel event-related potentials (ERPs), analysing the distractor-elicited N2pc component both canonically and using a multivariate electrical neuroimaging framework. Behaviourally, arbitrary target-matching distractors captured attention more strongly than semantically congruent ones, with no evidence for context modulating multisensory enhancements of capture. Notably, electrical neuroimaging of surface-level EEG analyses revealed context-based influences on attention to both visual and multisensory distractors, in how strongly they activated the brain and type of activated brain networks. For both processes, the context-driven brain response modulations occurred long before the N2pc time-window, with topographic (network-based) modulations at ∼30 ms, followed by strength-based modulations at ∼100 ms post-distractor onset. Our results reveal that both stimulus meaning and predictability modulate attentional selection, and they interact while doing so. Meaning, in addition to temporal predictability, is thus a second source of contextual information facilitating goal-directed behaviour. More broadly, in everyday situations, attention is controlled by an interplay between one's goals, stimuli's perceptual salience, meaning and predictability. Our study calls for a revision of attentional control theories to account for the role of contextual and multisensory control.

When Dogs Shrink the Typical Lengthening Effect Caused by Negative Emotions.

This paper examines how dogs can modulate the effects of emotion on time perception. To this end, participants performed a temporal bisection task with stimulus durations presented in the form of neutral or emotional facial expressions (angry, sad, and happy faces). In the first experiment, dog owners were compared with nondog owners, while in the second experiment, students were randomly assigned to one of the three waiting groups (waiting alone, with another person, or with a dog) before being confronted with the temporal bisection task. The results showed that dogs allowed the participants to regulate the intensity of negative emotional effects, while no statistical differences emerged for the happy facial expressions. In certain circumstances, dogs could even lead the subjects to generate underestimation of time when faced with negative facial expressions.

Stopwatch training improves cognitive functions in patients with Parkinson's disease.

Parkinson's disease (PD) impairs various cognitive functions, including time perception. Dysfunctional time perception in PD is poorly understood, and no study has investigated the rehabilitation of time perception in patients with PD. We aimed to induce the recovery of time perception in PD patients and investigated the potential relationship between recovery and cognitive functions/domains other than time perception. Sixty patients with PD (27 females) and 20 healthy controls (10 females) were recruited. The participants underwent a feedback training protocol for 4 weeks to improve the accuracy of subjective spatial distance or time duration using a ruler or stopwatch, respectively. They participated in three tests at weekly intervals, each comprising 10 types of cognitive tasks and assessments. After duration feedback training for 1 month, performance on the Go/No-go task, Stroop task, and impulsivity assessment improved in patients with PD, while no effect was observed after distance feedback training. Additionally, the effect of training on duration production correlated with extended reaction time and improved accuracy in the Go/No-go and Stroop tasks. These findings suggest that time perception is functionally linked to inhibitory systems. If the feedback training protocol can modulate and maintain time perception, it may improve various cognitive/psychiatric functions in patients with PD. It may also be useful in the treatment of diseases other than PD that cause dysfunctions in temporal processing.

The causal involvement of the right supramarginal gyrus in the subjective experience of time: A hf-tRNS study.

Neural populations in the supramarginal gyrus (SMG) of the right hemisphere have been shown to be involved in processing the subjective experience of time, particularly because of their selectivity to specific temporal durations. To directly investigate this relationship, we applied high-frequency transcranial Random Noise Stimulation (hf-tRNS) on the right SMG during a duration judgment task: 24 participants were required to judge the duration of a test visual stimulus (350, 450, 550, 650 ms) as shorter or longer than the duration of a reference auditory stimulus (500 ms). In half of the trials this procedure was preceded by a visual adaptation paradigm, used as a tool to manipulate the subjective experience of time: for 12 participants the adaptor was shorter than the test (250 ms), and for 12 participants it was longer than the test (750 ms). All participants performed an online hf-tRNS session and a sham control session. For each participant and for each condition, the Point of Subjective Equality (PSE) was calculated and results revealed an expected negative aftereffect in the group exposed to a longer adaptor. Moreover, hf-tRNS modulated participants' performance with respect to sham, confirming the involvement of the right SMG in temporal experience. Importantly, only in the group exposed to the longer adaptor, PSE values were higher during stimulation than during sham, only after the adaptation procedure (no difference emerged in trials without adaptation). This pattern of results confirms recent neuroimaging findings, and adds a direct evidence of the causal role of this area in subjective time experience.

Multisensory Integration Is Modulated by Hypnotizability.

This study investigated multisensory integration in 29 medium-to-high (mid-highs) and 24 low-to-medium (mid-lows) hypnotizable individuals, classified according to the Stanford Hypnotic Susceptibility Scale, Form A. Participants completed a simultaneity judgment (SJ) task, where an auditory and a visual stimulus were presented in close proximity to their body in a range of 11 stimulus onset asynchronies. Results show that mid-highs were prone to judge audiovisual stimuli as simultaneous over a wider range of time intervals between sensory stimuli, as expressed by a broader temporal binding window, when the visual stimulus precedes the auditory one. No significant difference was observed for response times. Findings indicate a role of hypnotizability in multisensory integration likely due to the highs' cerebellar peculiarities and/or sensory modality preference.

Temporal Prediction Signals for Periodic Sensory Events in the Primate Central Thalamus.

Prediction of periodic event timing is an important function for everyday activities, while the exact neural mechanism remains unclear. Previous studies in nonhuman primates have demonstrated that neurons in the cerebellar dentate nucleus and those in the caudate nucleus exhibit periodic firing modulation when the animals attempt to detect a single omission of isochronous repetitive audiovisual stimuli. To understand how these subcortical signals are sent and processed through the thalamocortical pathways, we examined single-neuron activities in the central thalamus of two macaque monkeys (one female and one male). We found that three types of neurons responded to each stimulus in the sequence in the absence of movements. Reactive-type neurons showed sensory adaptation and gradually waned the transient response to each stimulus. Predictive-type neurons steadily increased the magnitude of the suppressive response, similar to neurons previously reported in the cerebellum. Switch-type neurons initially showed a transient response, but after several cycles, the direction of firing modulation reversed and the activity decreased for each repetitive stimulus. The time course of Switch-type activity was well explained by the weighted sum of activities of the other types of neurons. Furthermore, for only Switch-type neurons the activity just before stimulus omission significantly correlated with behavioral latency, indicating that this type of neuron may carry a more advanced signal in the system detecting stimulus omission. These results suggest that the central thalamus may transmit integrated signals to the cerebral cortex for temporal information processing, which are necessary to accurately predict rhythmic event timing.SIGNIFICANCE STATEMENT Several cortical and subcortical regions are involved in temporal information processing, and the thalamus will play a role in functionally linking them. The present study aimed to clarify how the paralaminar part of the thalamus transmits and modifies signals for temporal prediction of rhythmic events. Three types of thalamic neurons exhibited periodic activity when monkeys attempted to detect a single omission of isochronous repetitive stimuli. The activity of one type of neuron correlated with the behavioral latency and appeared to be generated by integrating the signals carried by the other types of neurons. Our results revealed the neuronal signals in the thalamus for temporal prediction of sensory events, providing a clue to elucidate information processing in the thalamocortical pathways.