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Listeners often operate in complex acoustic environments, consisting of many concurrent sounds. Accurately encoding and maintaining such auditory objects in short‐term memory is crucial for communication and scene analysis. Yet, the neural underpinnings of successful auditory short‐term memory (ASTM) performance are currently not well understood. To elucidate this issue, we presented a novel, challenging auditory delayed match‐to‐sample task while recording MEG. Human participants listened to 'scenes' comprising three concurrent tone pip streams. The task was to indicate, after a delay, whether a probe stream was present in the just‐heard scene. We present three key findings: First, behavioural performance revealed faster responses in correct versus incorrect trials as well as in 'probe present' versus 'probe absent' trials, consistent with ASTM search. Second, successful compared with unsuccessful ASTM performance was associated with a significant enhancement of event‐related fields and oscillatory activity in the theta, alpha and beta frequency ranges. This extends previous findings of an overall increase of persistent activity during short‐term memory performance. Third, using distributed source modelling, we found these effects to be confined mostly to sensory areas during encoding, presumably related to ASTM contents per se. Parietal and frontal sources then became relevant during the maintenance stage, indicating that effective STM operation also relies on ongoing inhibitory processes suppressing task‐irrelevant information. In summary, our results deliver a detailed account of the neural patterns that differentiate successful from unsuccessful ASTM performance in the context of a complex, multi‐object auditory scene. [ABSTRACT FROM AUTHOR]

Temporal regularities are ubiquitous in our environment. The theory of entrainment posits that the brain can utilize these regularities by synchronizing neural activity with external events, thereby, aligning moments of high neural excitability with expected upcoming stimuli and facilitating perception. Despite numerous accounts reporting entrainment of behavioural and electrophysiological measures, evidence regarding this phenomenon remains mixed, with several recent studies having failed to provide confirmatory evidence. Notably, it is currently unclear whether and for how long the effects of entrainment can persist beyond their initiating stimulus, and whether they remain restricted to the stimulated sensory modality or can cross over to other modalities. Here, we set out to answer these questions by presenting participants with either visual or auditory rhythmic sensory stimulation, followed by a visual or auditory target at six possible time points, either in-phase or out-of-phase relative to the initial stimulus train. Unexpectedly, but in line with several recent studies, we observed no evidence for cyclic fluctuations in performance, despite our design being highly similar to those used in previous demonstrations of sensory entrainment. However, our data revealed a temporally less specific attentional effect, via cross-modally facilitated performance following auditory compared with visual rhythmic stimulation. In addition to a potentially higher salience of auditory rhythms, this could indicate an effect on oscillatory 3-Hz amplitude, resulting in facilitated cognitive control and attention. In summary, our study further challenges the generality of periodic behavioural modulation associated with sensory entrainment, while demonstrating a modality-independent attention effect following auditory rhythmic stimulation. [ABSTRACT FROM AUTHOR]

Recently, numerous studies have revealed 4–12 Hz fluctuations of behavioral performance in a multitude of tasks. The majority has utilized stimuli near detection threshold and observed related fluctuations in hit‐rates, attributing these to perceptual or attentional processes. As neural oscillations in the 8–20 Hz range also feature prominently in cortical motor areas, they might cause fluctuations in the ability to induce responses, independent of attentional capabilities. Additionally, different effectors (e.g., the left versus right hand) might be cyclically prioritized in an alternating fashion, similar to the attentional sampling of distinct locations, objects, or memory templates. Here, we investigated these questions via a behavioral dense‐sampling approach. Twenty‐six participants performed a simple visual discrimination task using highly salient stimuli. We varied the interval between each motor response and the subsequent target from 330 to 1040 ms, and analyzed performance as a function of this interval. Our data show significant fluctuations of both RTs and sensitivity between 12.5 and 25 Hz, but no evidence for an alternating prioritization of left‐ versus right‐hand responses. While our results suggest an impact of motor‐related signals on performance oscillations, they might additionally be influenced by perceptual processes earlier in the processing hierarchy. In summary, we demonstrate that behavioral oscillations generalize to situations involving highly salient stimuli, closer to everyday life. Moreover, our work adds to the literature by showing fluctuations at a high speed, which might be a consequence of both low task difficulty and the involvement of sensorimotor rhythms. Numerous studies have revealed 4‐12 Hz fluctuations in performance, using stimuli close to detection threshold. Here we report oscillations in response times and sensitivity at 12‐25 Hz, employing a simple task and highly salient stimuli. We conclude that the phenomenon can be generalized to situations closer to everyday life, while the higher frequency likely reflects both reduced task difficulty and the involvement of sensorimotor neural oscillations. [ABSTRACT FROM AUTHOR]

Representations held in working memory are crucial in guiding human attention in a goal-directed fashion. Currently, it is debated whether only a single representation or several of these representations can be active and bias behavior at any given moment. In the present study, 25 university students performed a behavioral dense-sampling experiment to produce an estimate of the temporal-activation patterns of two simultaneously held visual templates. We report two key novel results. First, performance related to both representations was not continuous but fluctuated rhythmically at 6 Hz. This corresponds to neural oscillations in the theta band, the functional importance of which in working memory is well established. Second, our findings suggest that two concurrently held representations may be prioritized in alternation, not simultaneously. Our data extend recent research on rhythmic sampling of external information by demonstrating an analogous mechanism in the cyclic activation of internal working memory representations. [ABSTRACT FROM AUTHOR]

In everyday life, we constantly need to remember the temporal sequence of visual events over short periods of time, for example, when making sense of others' actions or watching a movie. While there is increasing knowledge available on neural mechanisms underlying visual working memory (VWM) regarding the identity and spatial location of objects, less is known about how the brain encodes and retains information on temporal sequences. Here, we investigate whether the contralateral-delay activity (CDA), a well-studied electroencephalographic (EEG) component associated with VWM of object identity, also reflects the encoding and retention of temporal order. In two independent experiments, we presented participants with a sequence of four or six images, followed by a 1 s retention period. Participants judged temporal order by indicating whether a subsequently presented probe image was originally displayed during the first or the second half of the sequence. As a main novel result, we report the emergence of a contralateral negativity already following the presentation of the first item of the sequence, which increases over the course of a trial with every presented item, up to a limit of four items. We further observed no differences in the CDA during the temporal-order task compared to one obtained during a task concerning the spatial location of the presented items. Since the characteristics of the CDA appear to be highly similar between different encoded feature dimensions and increases as additional items are being encoded, we suggest this component might be a general characteristic of various types of VWM. • Contralateral delay activity is an EEG wave linked to visual-spatial working memory. • We show that this component can also be observed during temporal order working memory. • Further, its amplitude increases over time along with the number of retained items. • We suggest it is a general marker of visual working memory, independent of spatial attention. [ABSTRACT FROM AUTHOR]

We investigated the origin of attention capture in the contingent-capture protocol during a search for two colors. When searching for the target color, cues similar to the target capture attention but cues dissimilar to the target do not capture attention. The results are typically explained by top-down contingent capture, a form of proactive control where participants set up attentional control settings (ACSs) for the target and cues matching the ACSs capture attention. However, based on recent research, we hypothesized that the situation could be more complicated during search for several features. Here, reactive control in the form of (cue) color-elicited selection of one of several separate pre-activated ACSs, one for each single searched-for feature, could contribute to performance. With the help of mixing and switch costs, we demonstrated that participants searched for two colors by separate pre-activated ACSs, and a closer inspection of the capture effects of the cues confirmed that reactive control contributed to ACS selection. [ABSTRACT FROM AUTHOR]

Intersensory attention (IA) describes the process of directing attention to a specific modality. Temporal orienting (TO) characterizes directing attention to a specific moment in time. Previously, studies indicated that these two processes could have opposite effects on early evoked brain activity. The exact time-course and processing stages of both processes are still unknown. In this human electroencephalography study, we investigated the effects of IA and TO on visuo-tactile stimulus processing within one paradigm. IA was manipulated by presenting auditory cues to indicate whether participants should detect visual or tactile targets in visuo-tactile stimuli. TO was manipulated by presenting stimuli block-wise at fixed or variable inter-stimulus intervals. We observed that TO affects evoked activity to visuo-tactile stimuli prior to IA. Moreover, we found that TO reduces the amplitude of early evoked brain activity, whereas IA enhances it. Using beamformer source-localization, we observed that IA increases neural responses in sensory areas of the attended modality whereas TO reduces brain activity in widespread cortical areas. Based on these findings we derive an updated working model for the effects of temporal and intersensory attention on early evoked brain activity. [ABSTRACT FROM AUTHOR]

Stimulus-driven and top-down dependent capture of attention can be observed under very similar conditions, raising the question of the decisive factors for whether one or the other effect is seen. In the current study, we tested the role of temporal selectivity. Studies showing less evidence of stimulus-driven attention by salient color singletons often used sequences of displays, in which the first display contained an irrelevant color cue that could easily be ignored by timed allocation of attention, as the relevant target was consistently presented in a second display only. In contrast, studies showing more evidence of stimulus-driven attention used distractors presented simultaneously with the targets, making it more difficult to simply ignore additional salient distractors at the point in time where the target was presented. Here, we therefore tested stimulus-driven capture under two conditions: with temporal certainty that the first display could safely be ignored and without temporal certainty that the first display could be ignored. Results showed that this manipulation had no significant influence on stimulus-driven capture of attention by irrelevant but salient cues preceding the targets, although the same participants showed more distractor interference by a target-concomitant and salient color singleton. Thus, temporal selection was seemingly not the decisive factor for the amount of stimulus-driven capture of attention. [ABSTRACT FROM AUTHOR]

Knowledge about the sensory modality in which a forthcoming event might occur permits anticipatory intersensory attention. Information as to when exactly an event occurs enables temporal orienting. Intersensory and temporal attention mechanisms are often deployed simultaneously, but as yet it is unknown whether these processes operate interactively or in parallel. In this human electroencephalography study, we manipulated intersensory attention and temporal orienting in the same paradigm. A continuous stream of bisensory visuo-tactile inputs was presented, and a preceding auditory cue indicated to which modality participants should attend (visual or tactile). Temporal orienting was manipulated blockwise by presenting stimuli either at regular or irregular intervals. Using linear beamforming, we examined neural oscillations at virtual channels in sensory and motor cortices. Both attentional processes simultaneously modulated the power of anticipatory delta- and beta-band oscillations, as well as delta-band phase coherence. Modulations in sensory cortices reflected intersensory attention, indicative of modality-specific gating mechanisms. Modulations in motor and partly in somatosensory cortex reflected temporal orienting, indicative of a supramodal preparatory mechanism. We found no evidence for interactions between intersensory attention and temporal orienting, suggesting that these two mechanisms act in parallel and largely independent of each other in sensory and motor cortices. Hum Brain Mapp 36:3246-3259, 2015. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Several recent behavioral studies have observed 4–10 Hz rhythmic fluctuations in attention-related performance over time. So far, this rhythmic attentional sampling has predominantly been demonstrated with regards to external visual attention, directed toward one single feature dimension. Whether and how attention might sample from concurrent internal representations of different feature dimensions held in working memory (WM) is currently largely unknown. To elucidate this issue, we conducted a human behavioral dense-sampling experiment, in which participants had to hold representations of two distinct feature dimensions (color and orientation) in WM. By querying the contents of WM at 72 time-points after encoding, we estimated the activity time course of the individual feature representations. Our results demonstrate an oscillatory component at 9.4 Hz in the joint time courses of both representations, presumably reflecting a common early perceptual sampling process in the alpha-frequency range. Furthermore, we observed an oscillatory component at 3.5 Hz in the time course difference between the two representations. This likely corresponds to a later attentional sampling process and indicates that internal representations of distinct features are activated in alteration. In summary, we demonstrate the cyclic reactivation of internal WM representations of distinct feature dimensions, as well as the co-occurrence of behavioral fluctuations at distinct frequencies, presumably associated to internal perceptual- and attentional rhythms. In addition, our findings also challenge a model of strict parallel processing in visual search, thus, providing novel input to the ongoing debate on whether search for more than one target feature constitutes a parallel- or a sequential mechanism. • Visual working memory performance fluctuates at alpha and theta frequencies. • Alpha fluctuations suggest an early common perceptual sampling-mechanism. • Theta fluctuations suggest a later cyclic memory refreshment. • Memory for two features (orientation, color) is cyclically activated in alternation. • Our findings challenge a model of strict parallel processing in visual search. [ABSTRACT FROM AUTHOR]

Many electronic devices that we use in our daily lives provide inputs that need to be processed and integrated by our senses. For instance, ringing, vibrating, and flashing indicate incoming calls and messages in smartphones. Whether the presentation of multiple smartphone stimuli simultaneously provides an advantage over the processing of the same stimuli presented in isolation has not yet been investigated. In this behavioral study we examined multisensory processing between visual (V), tactile (T), and auditory (A) stimuli produced by a smartphone. Unisensory V, T, and A stimuli as well as VA, AT, VT, and trisensory VAT stimuli were presented in random order. Participants responded to any stimulus appearance by touching the smartphone screen using the stimulated hand (Experiment 1), or the non-stimulated hand (Experiment 2). We examined violations of the race model to test whether shorter response times to multisensory stimuli exceed probability summations of unisensory stimuli. Significant violations of the race model, indicative of multisensory processing, were found for VA stimuli in both experiments and for VT stimuli in Experiment 1. Across participants, the strength of this effect was not associated with prior learning experience and daily use of smartphones. This indicates that this integration effect, similar to what has been previously reported for the integration of semantically meaningless stimuli, could involve bottom-up driven multisensory processes. Our study demonstrates for the first time that multisensory processing of smartphone stimuli facilitates taking a call. Thus, research on multisensory integration should be taken into consideration when designing electronic devices such as smartphones. [ABSTRACT FROM AUTHOR]

In normal-hearing listeners, localization of auditory speech involves stimulus processing in the postero-dorsal pathway of the auditory system. In quiet environments, bilateral cochlear implant (CI) users show high speech recognition performance, but localization of auditory speech is poor, especially when discriminating stimuli from the same hemifield. Whether this difficulty relates to the inability of the auditory system to translate binaural electrical cues into neural signals, or to a functional reorganization of auditory cortical pathways following long periods of binaural deprivation is unknown. In this electroencephalography study, we examined the processing of auditory syllables in postlingually deaf adults with bilateral CIs and in normal-hearing adults. Participants were instructed to either recognize ('recognition' task) or localize ('localization' task) the syllables. The analysis focused on event-related potentials and oscillatory brain responses. N1 amplitudes in CI users were larger in the localization compared with recognition task, suggesting an enhanced stimulus processing effort in the localization task. Linear beamforming of oscillatory activity in CI users revealed stronger suppression of beta-band activity after 200 ms in the postero-dorsal auditory pathway for the localization compared with the recognition task. In normal-hearing adults, effects for longer latency event-related potentials were found, but no effects were observed for N1 amplitudes or beta-band responses. Our study suggests that difficulties in speech localization in bilateral CI users are not reflected in a functional reorganization of cortical auditory pathways. New signal processing strategies of cochlear devices preserving unambiguous binaural cues may improve auditory localization performance in bilateral CI users. Hum Brain Mapp 35:3107-3121, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

When viewing the needle of a syringe approaching your skin, anticipation of a painful prick may lead to increased arousal. How this anticipation is reflected in neural oscillatory activity and how it relates to activity within the autonomic nervous system is thus far unknown. Recently, we found that viewing needle pricks compared with Q-tip touches increases the pupil dilation response ( PDR) and perceived unpleasantness of electrical stimuli. Here, we used high-density electroencephalography to investigate whether anticipatory oscillatory activity predicts the unpleasantness of electrical stimuli and PDR while viewing a needle approaching a hand that is perceived as one's own. We presented video clips of needle pricks and Q-tip touches, and delivered spatiotemporally aligned painful and nonpainful intracutaneous electrical stimuli. The perceived unpleasantness of electrical stimuli and the PDR were enhanced when participants viewed needle pricks compared with Q-tip touches. Source reconstruction using linear beamforming revealed reduced alpha-band activity in the posterior cingulate cortex ( PCC) and fusiform gyrus before the onset of electrical stimuli when participants viewed needle pricks compared with Q-tip touches. Moreover, alpha-band activity in the PCC predicted PDR on a single trial level. The anticipatory reduction of alpha-band activity in the PCC may reflect a neural mechanism that serves to protect the body from forthcoming harm by facilitating the preparation of adequate defense responses. [ABSTRACT FROM AUTHOR]

Abstract: In our environment, acute pain is often accompanied by input from other sensory modalities, like visual stimuli, which can facilitate pain processing. To date, it is not well understood how these inputs influence the perception and processing of pain. Previous studies on integrative processing between sensory modalities other than pain have shown that multisensory response gains are strongest when the constituent unimodal stimuli are minimally effective in evoking responses. This finding has been termed the principle of inverse effectiveness (IE). In this high-density electroencephalography study, we investigated the influence of Gabor patches of low and high contrast levels on the perception and processing of spatially and temporally aligned painful electrical stimuli of low and high intensities. Subjective pain ratings, event-related potentials (ERPs) and oscillatory responses served as dependent measures. In line with the principle of IE, stronger crossmodal biasing effects of visual input on subjective pain ratings were found for low compared to high intensity painful stimuli. This effect was paralleled by stronger bimodal interactions in right-central ERPs (150–200ms) for low compared to high intensity pain stimuli. Moreover, an enhanced suppression of medio-central beta-band activity (12–24Hz, 200–400ms) was found for low compared to high intensity pain stimuli. Our findings possibly reflect a facilitation of stimulus processing that serves to enhance response readiness of the sensorimotor system following painful stimulation. Taken together, our study demonstrates that multisensory processing between visual and painful stimuli follows the principle of IE and suggests a role for beta-band oscillations in the crossmodal modulation of pain. [Copyright &y& Elsevier]

Abstract: Multistable visual perception refers to phenomena, in which one invariant stimulus pattern is perceived in at least two different, mutually exclusive ways. In this EEG study we differentiate between perceptual- and motor-related processes during perceptual reversals. Delta- and alpha-band activity was analyzed while participants answered to a perceptual reversal either immediately or with a delay of approximately 1500ms, thereby separating reversal-related and motor-related activity. On the single sweep level a reversal-related positive delta response and reversal-related desynchronisation of alpha activity could be detected irrespective of the motor response. Both conditions elicited the strongest reversal-related modulations at posterior locations. Contrary, motor-related responses were found predominantly at central locations. These findings were supported by a control experiment, using a slightly modified stimulus that allowed unambiguous perceptual changes to be triggered exogenously. In conclusion, this study demonstrates that the brain response to perceptual reversals differs from motor-related processes elicited by the button press indicating the perceptual reversal. The results of this study, therefore, indicate that perceptual- and motor-related processes are achieved in multiple selectively distributed and parallel working oscillatory networks of the brain. [Copyright &y& Elsevier]

Human listeners exhibit marked sensitivity to familiar music, perhaps most readily revealed by popular "name that tune" games, in which listeners often succeed in recognizing a familiar song based on extremely brief presentation. In this work, we used electroencephalography (EEG) and pupillometry to reveal the temporal signatures of the brain processes that allow differentiation between a familiar, well liked, and unfamiliar piece of music. In contrast to previous work, which has quantified gradual changes in pupil diameter (the so-called "pupil dilation response"), here we focus on the occurrence of pupil dilation events. This approach is substantially more sensitive in the temporal domain and allowed us to tap early activity with the putative salience network. Participants (N = 10) passively listened to snippets (750 ms) of a familiar, personally relevant and, an acoustically matched, unfamiliar song, presented in random order. A group of control participants (N = 12), who were unfamiliar with all of the songs, was also tested. We reveal a rapid differentiation between snippets from familiar and unfamiliar songs: Pupil responses showed greater dilation rate to familiar music from 100–300 ms post-stimulus-onset, consistent with a faster activation of the autonomic salience network. Brain responses measured with EEG showed a later differentiation between familiar and unfamiliar music from 350 ms post onset. Remarkably, the cluster pattern identified in the EEG response is very similar to that commonly found in the classic old/new memory retrieval paradigms, suggesting that the recognition of brief, randomly presented, music snippets, draws on similar processes. [ABSTRACT FROM AUTHOR]

Engaging in yoga may mitigate stress and anxiety in individuals while potentially enhancing one's capacity to manage distractions. Our research aimed to explore the relation between these two outcomes: Can an eight-week yoga program foster distraction suppression, thereby reducing stress and discomfort? To answer this question, we used Hatha Yoga, the most commonly practiced form of yoga. We tested if the intervention improved participants' ability to suppress distractions and selectively decrease self-reported stress and stress reactivity. In Addition, we investigated whether such an intervention would increase participants' mindfulness. Our study included 98 healthy yoga novices between 18 and 40 years who were randomly assigned to either an experimental or a waitlist condition, with each participant completing pre- and post-intervention assessments, including questionnaires, as well as electrophysiological and behavioral measures. After eight weeks of yoga practice, significant reductions in self-reported stress and stress reactivity levels, as well as increased mindfulness, were observed among those participating in the intervention relative to those in the waitlist control group. There were, however, no significant changes in state or trait anxiety due to the intervention. Changes in stress measures could not be explained by changes in participants' ability to suppress distractors, which was not affected by the intervention. Overall, our findings suggest that regular participation in Hatha Yoga can improve mental health outcomes without impacting cognitive functioning directly related to distractor suppression. NCT05232422 [ABSTRACT FROM AUTHOR]

From auditory perception to general cognition, the ability to play a musical instrument has been associated with skills both related and unrelated to music. However, it is unclear if these effects are bound to the specific characteristics of musical instrument training, as little attention has been paid to other populations such as audio engineers and designers whose auditory expertise may match or surpass that of musicians in specific auditory tasks or more naturalistic acoustic scenarios. We explored this possibility by comparing students of audio engineering (n = 20) to matched conservatory-trained instrumentalists (n = 24) and to naive controls (n = 20) on measures of auditory discrimination, auditory scene analysis, and speech in noise perception. We found that audio engineers and performing musicians had generally lower psychophysical thresholds than controls, with pitch perception showing the largest effect size. Compared to controls, audio engineers could better memorise and recall auditory scenes composed of non-musical sounds, whereas instrumental musicians performed best in a sustained selective attention task with two competing streams of tones. Finally, in a diotic speech-in-babble task, musicians showed lower signal-to-noise-ratio thresholds than both controls and engineers; however, a follow-up online study did not replicate this musician advantage. We also observed differences in personality that might account for group-based self-selection biases. Overall, we showed that investigating a wider range of forms of auditory expertise can help us corroborate (or challenge) the specificity of the advantages previously associated with musical instrument training. [ABSTRACT FROM AUTHOR]