Temporal expectancies driven by self- and externally generated rhythms

The dynamic attending theory proposes that rhythms entrain periodic fluctuations of attention which modulate the gain of sensory input. However, temporal expectancies can also be driven by the mere passage of time (foreperiod effect). It is currently unknown how these two types of temporal expectancy relate to each other, i.e. whether they work in parallel and have distinguishable neural signatures. The current research addresses this issue. Participants either tapped a 1Hz rhythm (active task) or were passively presented with the same rhythm using tactile stimulators (passive task). Based on this rhythm an auditory target was then presented early, in synchrony, or late. Behavioural results were in line with the dynamic attending theory as RTs were faster for in- compared to out-of-synchrony targets. Electrophysiological results suggested self-generated and externally induced rhythms to entrain neural oscillations in the delta frequency band. Auditory ERPs showed evidence of two distinct temporal expectancy processes. Both tasks demonstrated a pattern which followed a linear foreperiod effect. In the active task, however, we also observed an ERP effect consistent with the dynamic attending theory. This study shows that temporal expectancies generated by a rhythm and expectancy generated by the mere passage of time can work in parallel and sheds light on how these mechanisms are implemented in the brain

Musical rhythm effects on visual attention are non-rhythmical: Evidence against metrical entrainment

The idea that external rhythms synchronize attention cross-modally has attracted much interest and scientific inquiry. Yet, whether associated attentional modulations are indeed rhythmical in that they spring from and map onto an underlying meter has not been clearly established. Here we tested this idea while addressing the shortcomings of previous work associated with confounding (i) metricality and regularity, (ii) rhythmic and temporal expectations or (iii) global and local temporal effects. We designed sound sequences that varied orthogonally (high/low) in metricality and regularity and presented them as task-irrelevant auditory background in four separate blocks. The participants' task was to detect rare visual targets occurring at a silent metrically aligned or misaligned temporal position. We found that target timing was irrelevant for reaction times and visual event-related potentials. High background regularity and to a lesser extent metricality facilitated target processing across metrically aligned and misaligned positions. Additionally, high regularity modulated auditory background frequencies in the EEG recorded over occipital cortex. We conclude that external rhythms, rather than synchronizing attention cross-modally, confer general, nontemporal benefits. Their predictability conserves processing resources that then benefit stimulus representations in other modalities

Music, Language, and Rhythmic Timing

Neural, perceptual, and cognitive oscillations synchronize with rhythmic events in both speech (Luo & Poeppel, 2007) and music (Snyder & Large, 2005). This synchronization decreases perceptual thresholds to temporally predictable events (Lawrance et al., 2014), improves task performance (Ellis & Jones, 2010), and enables speech intelligibility (Peelle & Davis, 2012). Despite implications of music-language transfer effects for improving language outcomes (Gordon et al., 2015), proposals that shared neural and cognitive resources underlie music and speech rhythm perception (e.g., Tierney & Kraus, 2014) are not yet substantiated. The present research aimed to explore this potential overlap by testing whether music-induced oscillations affect metric speech tempo perception, and vice versa. We presented in each of 432 trials a prime sequence (seven repetitions of either a metric speech utterance or analogous musical phrase) followed by a standard-comparison pair (either two identical speech utterances or two identical musical phrases). Twenty-two participants judged whether the comparison was slower than, faster than, or the same tempo as the standard. We manipulated whether the prime was slower than, faster than, or the same tempo as the standard. Tempo discrimination accuracy was higher when the standard tempo was the same as, compared to slower or faster than, the prime tempo. These findings support the shared-resources view more than the independent-resources view, and they have implications for music-language transfer effects showing improvements in verbal memory (Chan et al., 1998), speech-in-noise perception (Strait et al., 2012), and reading ability in children and adults (Tierney & Kraus, 2013)

Electrophysiological signatures of conscious perception: The influence of cognitive, cortical and pathological states on multisensory integration

At any given moment, information reaches us via our different sensory systems. In order to navigate this multitude of information, associated information needs to be integrated to a coherent percept. In recent years, the hypothesis that synchronous neural oscillations play a prominent role in unisensory and multisensory processing has received substantial support. Current findings further convey the idea that local oscillations and functional connectivity reflect bottom-up as well as top-down processes during multisensory integration and perception. In the current work, I review recent findings on the role of neural oscillations for conscious multisensory perception. Subsequently, I present an integrative network model for multisensory integration that describes the cortical correlates of conscious multisensory perception, the influence of fluctuations of oscillatory neural activity on subsequent perception, and the influence of cognitive processes on neural oscillations and perception. I propose that neural oscillations in distinct, coexisting frequencies reflect the various processing steps underlying multisensory perception.Jederzeit erreichen uns Informationen über unsere verschiedenen Sinnesorgane und Wahrnehmungssysteme. Um in dieser Menge an Informationen den Überblick zu behalten, müssen zusammengehörige Informationen zu einer kohärente Wahrnehmung zusammengefügt werden. In den letzten Jahren hat die Hypothese, dass synchrone neuronale Oszillationen eine wichtige Rolle bei der Verarbeitung von unisensorischen und multisensorischen Reizen spielen, viel Unterstützung erfahren. Neueste Befunde befördern weiterhin die Idee, dass lokale Oszillationen und funktionale Konnektivität aufsteigende und absteigende Prozesse bei multisensorischer Integration und Wahrnehmung widerspiegeln. In dieser Arbeit werde ich einen Überblick über die neuesten Befunde zur Rolle neuronaler Oszillationen bei bewusster, multisensorischer Wahrnehmung geben. Anschließend werde ich ein integratives Netzwerkmodell multisensorischer Wahrnehmung präsentieren, welches die kortikalen Korrelate bewusster, multisensorischer Wahrnehmung, den Einfluss von Schwankungen oszillatorischer neuronaler Aktivität auf darauffolgende Wahrnehmung, sowie den Einfluss kognitiver Prozesse auf neuronale Oszillationen und Wahrnehmung beschreibt. Ich schlage vor, dass neuronale Oszillationen in umschriebenen, gleichzeitig aktiven Frequenzbändern die verschiedenen Verarbeitungsschritte widerspiegeln, welche multisensorischer Wahrnehmung zugrunde liegen

Null effects of temporal prediction on recognition memory but evidence for differential neural activity at encoding. A registered report

Previous research has demonstrated that rhythmic presentation of stimuli during encoding boosts subsequent recognition and is associated with distinct neural activity compared with when stimuli are presented in an arrhythmic manner. However, it is unclear whether the effect is driven by automatic entrainment to rhythm or non-rhythmic temporal prediction. This registered report presents an Electroencephalographic (EEG) study aimed at establishing the cognitive and neural mechanisms of the effect of temporal prediction on recognition. In a blocked design, stimulus onset during encoding was systematically manipulated in four conditions prior to recognition testing: rhythmic fixed (RF), rhythmic variable (RV), arrhythmic fixed (AF), and arrhythmic variable (AV). By orthogonally varying rhythm and temporal position we were able to assess their independent contributions to recognition enhancement. Our behavioural results did not replicate previous findings that show a difference in recognition memory based on temporal predictability at encoding. However, event-related potential (ERP) component analysis did show an early (N1) interaction effect of temporal position and rhythm, and later (N2 and Dm) effects driven by temporal position only. Taken together, we observed effects of temporal prediction at encoding, but these differences did not translate to later effects of memory, suggesting that effects of temporal prediction on recognition are less robust than previously thought