Listening Task Research Articles

Cognitive Workload in an Auditory Digit Span Task When Memory Span Is in the Neighborhood of Seven Items

Abstract. Task performance of digit span has been widely used in the research on human short-term memory. The present study was conducted to show that the dynamic change of underlying mental effort can be further estimated by measuring the strength of theta oscillations at a forehead site on the scalp. Fourteen healthy adults ( Mage = 26.1 years) performed a passive listening (PL) task and an auditory digit span (DS) task, and electroencephalography (EEG) data were recorded simultaneously during the two tasks. Considering that the digit span paradigm has often been conducted in a non-laboratory location, the EEG data were collected with a wireless single-channel headset system. The headset system was validated in this study by replicating the EEG (an enhancement of frontal theta power) as well as event-related potential (N200 and P300) responses to the deviant tone stimuli in the PL task. The outcomes of the DS task showed that the memory span of the participants was at least eight items. Moreover, frontal theta power in response to a list of six to eight digits increased significantly. This pattern of results supports a hypothesis that additional mental effort is required for short-term retention of verbal items when the number of stimulus items exceeds the newly proposed limit of short-term memory capacity. Some strengths and limitations of the current EEG headset system are also discussed.

Mindfulness interventions improve momentary and trait measures of attentional control: Evidence from a randomized controlled trial.

Mindfulness interventions have been shown to improve several subcomponents of attention; however, the psychological mechanisms driving these improvements are unknown. Mindfulness interventions train individuals to monitor present moment experiences while adopting an attitude of acceptance toward these experiences. We conducted a theoretically driven randomized controlled trial to test the putative mechanisms of mindfulness training that drive improvements in attentional control. Participants were randomly assigned to 1 of 3 conditions: (a) monitor and accept (MA) training, a standard 8-week mindfulness-based stress reduction (MBSR) intervention that included cultivation of both monitoring and acceptance skills; (b) monitor only (MO) training, a well-matched modified 8-week MBSR-adapted intervention that focused on monitoring skills only; or (c) no treatment (NT) control. Momentary attentional control was measured via ecological momentary assessment for 3 days at baseline and postintervention. Trait attentional control was assessed at baseline and postintervention using traditional self-report. Participants also completed a dichotic listening task to assess sustained attention at baseline and postintervention. We found that MA and MO participants improved in momentary and trait attentional control (but not attention task performance) relative to NT participants. Analyses of indirect effects were consistent with the possibility that increased momentary attentional control partially accounts for MA/MO intervention-related increases in trait attentional control. This randomized controlled trial provides one of the first experimental tests of the mechanisms of mindfulness interventions that drive improvements in attention outcomes. These findings support the notion that present-focused monitoring skills training drives mindfulness intervention-related improvements in momentary attentional control, which in turn fosters greater trait attentional control. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Dichotic listening performance with cochlear-implant simulations of ear asymmetry is consistent with difficulty ignoring clearer speech.

There are an increasing number of bilateral and single-sided-deafness cochlear-implant (CI) users who hope to achieve improved spatial-hearing abilities through access to sound in both ears. It is, however, unclear how speech is processed when inputs are functionally asymmetrical, which may have an impact on spatial-hearing abilities. Therefore, functionally asymmetrical hearing was controlled and parametrically manipulated using a channel vocoder as a CI simulation. In Experiment 1, normal-hearing (NH) listeners performed a dichotic listening task (i.e., selective attention to one ear, ignoring the other) using asymmetrical signal degradation. Spectral resolution varied independently in each ear (4, 8, 16 channels, and unprocessed control). Performance decreased with decreasing resolution in the target ear and increasing resolution in the interferer ear. In Experiment 2, these results were replicated using a divided attention task (attend to both ears, report one after sentence completion) in both NH and bilateral CI listeners, although overall performance was lower than in Experiment 1. In Experiment 3, frequency-to-place mismatch simulated shallow CI insertion depths (0, 3, 6-mm shifts, and unprocessed control). Performance mostly decreased with increasing shift in the target ear and decreasing shift in the interferer ear; however, performance nonmonotonicities occurred. The worst performance occurred when the shift matched across ears, suggesting that pitch similarity increases difficulty. The results show that it is more difficult to attend an ear that is relatively degraded or distorted, which may set spatial-hearing limitations for CI users when trying to attend to a target in complex auditory scenes.

Text Authenticity in Listening Assessment: Can Item Writers Be Trained to Produce Authentic-sounding Texts?

ABSTRACT A long-standing debate in the testing of listening concerns the authenticity of the listening input. On the one hand, listening texts produced by item writers often lack spoken language characteristics. On the other hand, real-life recordings are often too context-specific to stand alone, or not suitable for item generation. In this study, we explored the effectiveness of an existing item-writing training course to produce authentic-sounding listening texts within the constraints of test specifications. Twenty-five trainees took an online item-writing course including training on creating authentic-sounding listening texts. Prior to and after the course, they developed a listening task. The resulting listening texts were judged on authenticity by three professional item reviewers and analysed linguistically by the researchers. Additionally, we interviewed the trainees following each item writing event and analysed their online discussions from during the course. Statistical comparison of the pre-and post-course authenticity scores revealed a positive effect of the training on item-writers’ ability to produce authentic-sounding listening texts, while the linguistic analysis demonstrated that the texts produced after the training contained more instances of spoken language. The interviews and discussions revealed that item writers’ awareness of spoken language features and their text production techniques influenced their ability to develop authentic-sounding texts.

Previously reward-associated sounds interfere with goal-directed auditory processing.

Previously reward-associated stimuli have consistently been shown to involuntarily capture attention in the visual domain. Although previously reward-associated but currently task-irrelevant sounds have also been shown to interfere with visual processing, it remains unclear whether such stimuli can interfere with the processing of task-relevant auditory information. To address this question, we modified a dichotic listening task to measure interference from task-irrelevant but previously reward-associated sounds. In a training phase, participants were simultaneously presented with a spoken letter and number in different auditory streams and learned to associate the correct identification of each of three letters with high, low, and no monetary reward, respectively. In a subsequent test phase, participants were again presented with the same auditory stimuli but were instead instructed to report the number while ignoring spoken letters. In both the training and test phases, response time measures demonstrated that attention was biased in favour of the auditory stimulus associated with high value. Our findings demonstrate that attention can be biased towards learned reward cues in the auditory domain, interfering with goal-directed auditory processing.

A preregistered replication and extension of the cocktail party phenomenon: One's name captures attention, unexpected words do not.

In the cocktail party phenomenon, participants cannot attend to more than 1 stream of information, but sometimes detect their own name being presented in the irrelevant message during a selective listening task. Here we present a preregistered replication of the phenomenon, in which we also tested whether semantically unexpected words have a similar effect and whether individual differences in working memory capacity as measured by the operation and running-span tasks are related to the ability to detect one's own name or unexpected words in the irrelevant message. Twenty-nine percent of the participants reported noticing their own name, and those who did made more errors on relevant, to-be-shadowed words presented around the time of the name. Low-span participants were more likely than high-span participants to notice their names and to commit shadowing errors concurrently to the presentation of the name or shortly after. In contrast, semantically unexpected words were rarely detected, nor were they associated with shadowing errors in the relevant message. Our results demonstrate once again that highly relevant stimuli such as one's own name are capable of attracting and capturing attention for a short period of time. Our results also demonstrate that unexpected words within sentences do not belong to this category of stimuli. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Cognitive Processing of Miscommunication in Interactive Listening: An Evaluation of Listener Indecision and Cognitive Effort.

Purpose The purpose of the current study was to evaluate the social and cognitive underpinnings of miscommunication during an interactive listening task. Method An eye and computer mouse-tracking visual-world paradigm was used to investigate how a listener's cognitive effort (local and global) and decision-making processes were affected by a speaker's use of ambiguity that led to a miscommunication. Results Experiments 1 and 2 found that an environmental cue that made a miscommunication more or less salient impacted listener language processing effort (eye-tracking). Experiment 2 also indicated that listeners may develop different processing heuristics dependent upon the speaker's use of ambiguity that led to a miscommunication, exerting a significant impact on cognition and decision making. We also found that perspective-taking effort and decision-making complexity metrics (computer mouse tracking) predict language processing effort, indicating that instances of miscommunication produced cognitive consequences of indecision, thinking, and cognitive pull. Conclusion Together, these results indicate that listeners behave both reciprocally and adaptively when miscommunications occur, but the way they respond is largely dependent upon the type of ambiguity and how often it is produced by the speaker.

Is Training with the N-Back Task More Effective Than with Other Tasks? N-Back vs. Dichotic Listening vs. Simple Listening

Cognitive training most commonly uses computerized tasks that stimulate simultaneous cognitive processing in two modalities, such as a dual n-back task with visual and auditive stimuli, or on two receptive channels, such as a listening task with dichotically presented stimuli. The present study was designed to compare a dual n-back task and a dichotic listening (DL) task with an active control condition (a simple listening task) and a no-training control condition for their impact on cognitive performance, daily life memory, and mindfulness. One hundred thirty healthy adults aged 18–55 years were randomly assigned to one of the four conditions. The training consisted of twenty 15-min sessions spread across 4 weeks. The results indicated some improvement on episodic memory tasks and a trend for enhanced performance in an untrained working memory (WM) span task following cognitive training relative to the no-training control group. However, the only differential training effects were found for the DL training in increasing choice reaction performance and a trend for self-reported mindfulness. Transfer to measures of fluid intelligence and memory in daily life did not emerge. Additionally, we found links between self-efficacy and n-back training performance and between emotion regulation and training motivation. Our results contribute to the field of WM training by demonstrating that our listening tasks are comparable in effect to a dual n-back task in slightly improving memory. The possibility of improving attentional control and mindfulness through dichotic listening training is promising and deserves further consideration.

Cortical processing of distracting speech in noisy auditory scenes depends on perceptual demand

Selective attention is essential for the processing of multi-speaker auditory scenes because they require the perceptual segregation of the relevant speech (“target”) from irrelevant speech (“distractors”). For simple sounds, it has been suggested that the processing of multiple distractor sounds depends on bottom-up factors affecting task performance. However, it remains unclear whether such dependency applies to naturalistic multi-speaker auditory scenes.In this study, we tested the hypothesis that increased perceptual demand (the processing requirement posed by the scene to separate the target speech) reduces the cortical processing of distractor speech thus decreasing their perceptual segregation. Human participants were presented with auditory scenes including three speakers and asked to selectively attend to one speaker while their EEG was acquired. The perceptual demand of this selective listening task was varied by introducing an auditory cue (interaural time differences, ITDs) for segregating the target from the distractor speakers, while acoustic differences between the distractors were matched in ITD and loudness. We obtained a quantitative measure of the cortical segregation of distractor speakers by assessing the difference in how accurately speech-envelope following EEG responses could be predicted by models of averaged distractor speech versus models of individual distractor speech. In agreement with our hypothesis, results show that interaural segregation cues led to improved behavioral word-recognition performance and stronger cortical segregation of the distractor speakers. The neural effect was strongest in the δ-band and at early delays (0 − 200 ms).Our results indicate that during low perceptual demand, the human cortex represents individual distractor speech signals as more segregated. This suggests that, in addition to purely acoustical properties, the cortical processing of distractor speakers depends on factors like perceptual demand.

Correlates of Auditory Decision-Making in Prefrontal, Auditory, and Basal Lateral Amygdala Cortical Areas.

Spatial selective listening and auditory choice underlie important processes including attending to a speaker at a cocktail party and knowing how (or whether) to respond. To examine task encoding and the relative timing of potential neural substrates underlying these behaviors, we developed a spatial selective detection paradigm for monkeys, and recorded activity in primary auditory cortex (AC), dorsolateral prefrontal cortex (dlPFC), and the basolateral amygdala (BLA). A comparison of neural responses among these three areas showed that, as expected, AC encoded the side of the cue and target characteristics before dlPFC and BLA. Interestingly, AC also encoded the choice of the monkey before dlPFC and around the time of BLA. Generally, BLA showed weak responses to all task features except the choice. Decoding analyses suggested that errors followed from a failure to encode the target stimulus in both AC and dlPFC, but again, these differences arose earlier in AC. The similarities between AC and dlPFC responses were abolished during passive sensory stimulation with identical trial conditions, suggesting that the robust sensory encoding in dlPFC is contextually gated. Thus, counter to a strictly PFC-driven decision process, in this spatial selective listening task AC neural activity represents the sensory and decision information before dlPFC. Unlike in the visual domain, in this auditory task, the BLA does not appear to be robustly involved in selective spatial processing.SIGNIFICANCE STATEMENT We examined neural correlates of an auditory spatial selective listening task by recording single-neuron activity in behaving monkeys from the amygdala, dorsolateral prefrontal cortex, and auditory cortex. We found that auditory cortex coded spatial cues and choice-related activity before dorsolateral prefrontal cortex or the amygdala. Auditory cortex also had robust delay period activity. Therefore, we found that auditory cortex could support the neural computations that underlie the behavioral processes in the task.

The effect of linguistic propositions on the collection of Arabic language norms and the development of critical thinking among middle-grade students.

The reality of teaching the Arabic language rules is not satisfactory, as the pedagogical methods used do not help students develop their mental skills, especially critical thinking skills. They are often traditional in terms of teaching students, who are passive, passive, often passive, active, and often active, their listening task, and the teacher's task of narrating facts and judgments. It is a blind simulation student, a dependency on others, and a weak spirit of creativity, innovation, and opinion. The opinions of educators and teachers almost agree on the reasons for students' weakness in learning the rules of Arabic, and that the reason lies in the way of teaching. The difficulty or the ease of the rules of Arabic does not lie in the same rules, but in the teaching method The study was aimed at learning the impact of language pros on Arabic language proficiency and development of critical thinking among middle-grade students. In order to achieve the two search goals, the two sub-researchers have developed the following two hypothmia: —there is no statistically significant difference at an indication level (0.05) between the average scores of experimental group students who study using language. Among the average scores of control group students who study the traditional method of the dimensional test. —there is no statistically significant difference at an indication level (0.05) between the average grade of the group's experimental students in the pre- and dimensional quiz in the critical thinking scale. The search sample (63) students reached. The final sum of the sample to which the test will be applied (30) became students for each of the two research groups, and rewarded the researcher between the two groups in a set of variables. The researcher has relied on two tools (the test of inquiry) and (the critical thinking test) and has extracted their cycometric properties. The researcher used statistical methods (T/K Box/Pearson Link) . The search resulted in the following results: – a statistically significant difference for the experimental group in the dimensional test. – there is a statistically significant difference in favor of a dimensional application of critical thinking testing. In the light of the findings of the researcher, it is possible to conclude the following: 1. The use of language (language) contributes to the raising of the level of first grade students in Arabic grammar, as the results of the research show that the experimental group is superior to the control group. Within the results of this research, which has shown a positive impact on the group's trial, the following recommendations can be made: 1. The adoption of an effective method of teaching Arabic grammar to middle grade students. Following this research, the researcher suggests the following: 1. Conduct a similar study of current study in variables other than achievement such as: (Development of trends and trends, development of innovative thinking, critical thinking, and trend toward science).

Dichotic listening performance and interhemispheric integration after stress exposure

Functional hemispheric asymmetries (FHAs) have been thought to be relatively stable over time. However, past research has shown that FHAs are more plastic than initially thought. Endocrinological processes have been demonstrated to alter FHAs. As the product of the stress-activated hypothalamus–pituitary–adrenal axis, cortisol influences information processing at every level from stimulus perception to decision making and action. To investigate the influence of acute stress on FHAs, 60 participants performed a Banich–Belger task, as well as a verbal and an emotional dichotic listening task in two sessions. One session included a stress induction via the Trier Social Stress Test, the other session included a control procedure. We calculated across-field advantages (AFAs) in the Banich–Belger task and lateralization quotients for reaction times and responses per side in both dichotic listening tasks. There were no significant differences between the stress and control session in the dichotic listening tasks. In contrast, there was evidence for an influence of cortisol and sympathetic activation indicated by salivary alpha amylase changes on AFAs in the Banich–Belger task. This indicates that acute stress and the related increase in cortisol do not influence dichotic listening performance. However, stress does seem to affect interhemispheric integration of information. Future research using EEG, fMRI and pharmacological interventions is needed to further characterize the relation of hemispheric asymmetries and acute stress.

EEG Correlates of Learning From Speech Presented in Environmental Noise.

How the human brain retains relevant vocal information while suppressing irrelevant sounds is one of the ongoing challenges in cognitive neuroscience. Knowledge of the underlying mechanisms of this ability can be used to identify whether a person is distracted during listening to a target speech, especially in a learning context. This paper investigates the neural correlates of learning from the speech presented in a noisy environment using an ecologically valid learning context and electroencephalography (EEG). To this end, the following listening tasks were performed while 64-channel EEG signals were recorded: (1) attentive listening to the lectures in background sound, (2) attentive listening to the background sound presented alone, and (3) inattentive listening to the background sound. For the first task, 13 lectures of 5 min in length embedded in different types of realistic background noise were presented to participants who were asked to focus on the lectures. As background noise, multi-talker babble, continuous highway, and fluctuating traffic sounds were used. After the second task, a written exam was taken to quantify the amount of information that participants have acquired and retained from the lectures. In addition to various power spectrum-based EEG features in different frequency bands, the peak frequency and long-range temporal correlations (LRTC) of alpha-band activity were estimated. To reduce these dimensions, a principal component analysis (PCA) was applied to the different listening conditions resulting in the feature combinations that discriminate most between listening conditions and persons. Linear mixed-effect modeling was used to explain the origin of extracted principal components, showing their dependence on listening condition and type of background sound. Following this unsupervised step, a supervised analysis was performed to explain the link between the exam results and the EEG principal component scores using both linear fixed and mixed-effect modeling. Results suggest that the ability to learn from the speech presented in environmental noise can be predicted by the several components over the specific brain regions better than by knowing the background noise type. These components were linked to deterioration in attention, speech envelope following, decreased focusing during listening, cognitive prediction error, and specific inhibition mechanisms.

Single-cell activity in human STG during perception of phonemes is organized according to manner of articulation

One of the central tasks of the human auditory system is to extract sound features from incoming acoustic signals that are most critical for speech perception. Specifically, phonological features and phonemes are the building blocks for more complex linguistic entities, such as syllables, words and sentences. Previous ECoG and EEG studies showed that various regions in the superior temporal gyrus (STG) exhibit selective responses to specific phonological features. However, electrical activity recorded by ECoG or EEG grids reflects average responses of large neuronal populations and is therefore limited in providing insights into activity patterns of single neurons. Here, we recorded spiking activity from 45 units in the STG from six neurosurgical patients who performed a listening task with phoneme stimuli. Fourteen units showed significant responsiveness to the stimuli. Using a Naïve-Bayes model, we find that single-cell responses to phonemes are governed by manner-of-articulation features and are organized according to sonority with two main clusters for sonorants and obstruents. We further find that ‘neural similarity’ (i.e. the similarity of evoked spiking activity between pairs of phonemes) is comparable to the ‘perceptual similarity’ (i.e. to what extent two phonemes are judged as sounding similar) based on perceptual confusion, assessed behaviorally in healthy subjects. Thus, phonemes that were perceptually similar also had similar neural responses. Taken together, our findings indicate that manner-of-articulation is the dominant organization dimension of phoneme representations at the single-cell level, suggesting a remarkable consistency across levels of analyses, from the single neuron level to that of large neuronal populations and behavior.

Mental Effort When Playing, Listening, and Imagining Music in One Pianist's Eyes and Brain.

We investigated “musical effort” with an internationally renowned, classical, pianist while playing, listening, and imagining music. We used pupillometry as an objective measure of mental effort and fMRI as an exploratory method of effort with the same musical pieces. We also compared a group of non-professional pianists and non-musicians by the use of pupillometry and a small group of non-musicians with fMRI. This combined approach of psychophysiology and neuroimaging revealed the cognitive work during different musical activities. We found that pupil diameters were largest when “playing” (regardless of whether there was sound produced or not) compared to conditions with no movement (i.e., “listening” and “imagery”). We found positive correlations between pupil diameters of the professional pianist during different conditions with the same piano piece (i.e., normal playing, silenced playing, listen, imagining), which might indicate similar degrees of load on cognitive resources as well as an intimate link between the motor imagery of sound-producing body motions and gestures. We also confirmed that musical imagery had a strong commonality with music listening in both pianists and musically naïve individuals. Neuroimaging provided evidence for a relationship between noradrenergic (NE) activity and mental workload or attentional intensity within the domain of music cognition. We found effort related activity in the superior part of the locus coeruleus (LC) and, similarly to the pupil, the listening and imagery engaged less the LC–NE network than the motor condition. The pianists attended more intensively to the most difficult piece than the non-musicians since they showed larger pupils for the most difficult piece. Non-musicians were the most engaged by the music listening task, suggesting that the amount of attention allocated for the same task may follow a hierarchy of expertise demanding less attentional effort in expert or performers than in novices. In the professional pianist, we found only weak evidence for a commonality between subjective effort (as rated measure-by-measure) and the objective effort gauged with pupil diameter during listening. We suggest that psychophysiological methods like pupillometry can index mental effort in a manner that is not available to subjective awareness or introspection.

Auditory distraction, capacity limitations, and target-distractor relationships under perceptual and cognitive loads

Auditory distraction occurs when unwanted sounds interfere with the perception or processing of target information. Cross-modal paradigms have identified target-distractor similarities, capacity limitations, and type of task load as factors that influence distractibility. Given the scarceness of data specific to the auditory domain, this study investigated contributions from these factors across four listening tasks varying in perceptual (PL) and cognitive load (CL). Thirty adults (M = 23.65 years) participated in all conditions and were divided into high- or low-working memory capacity (WMC) groups following a listening-span task. Targets were spoken-digits (1-through-9) and distractors were either “Standards” (80% of trials) or one of three “Deviants” (noise-bursts, consonants, spoken-digits; 20% of trials). Experiment 1, high-PL, and Experiment 4, high-CL, were the only two conditions yielding effects of WMC and distractors. Under high-PL, high-WMC group reaction times (RTs) were both longer overall (p = 0.026) and in the presence of spoken-digit distractors (p = 0.014). In contrast, under high-CL, low-WMC group RTs were longer overall (p < 0.01) and spoken-digit distractors affected both groups (p < 0.01). Experiments 2 and 3 shared low-PL and CL, resulting in no effects. Patterns suggest that load type for a given listening task drives how capacity limitations and target-distractor similarities impact auditory distractibility.

Altered neuronal habituation to hearing others\u2019 pain in adults with autistic traits

This study tested the hypothesis that autistic traits influence the neuronal habituation that underlies the processing of others’ pain. Based on their autism-spectrum quotient (AQ), two groups of participants were classified according to their autistic traits: High-AQ and Low-AQ groups. Their event-related potentials in response to trains of three identical audio recordings, exhibiting either painful or neutral feelings of others, were compared during three experimental tasks. (1) In a Pain Judgment Task, participants were instructed to focus on pain-related cues in the presented audio recordings. (2) In a Gender Judgment Task, participants were instructed to focus on non-pain-related cues in the presented audio recordings. (3) In a Passive Listening Task, participants were instructed to passively listen. In the High-AQ group, an altered empathic pattern of habituation, indexed by frontal-central P2 responses of the second repeated painful audio recordings, was found during the Passive Listening Task. Nevertheless, both High-AQ and Low-AQ groups exhibited similar patterns of habituation to hearing others’ voices, both neutral and painful, in the Pain Judgment and Gender Judgment Tasks. These results suggest altered empathic neuronal habituation in the passive processing of others’ vocal pain by individuals with autistic traits.

A multimodal study of the effects of tDCS on dorsolateral prefrontal and temporo-parietal areas during dichotic listening.

The underlying neural mechanisms of transcranial direct current stimulation (tDCS), especially beyond the primary motor cortex, remain unclear. Several studies examined tDCS effects on either functional activity, neurotransmitters or behavior but few investigated those aspects together to reveal how the brain responds to tDCS. The objective is to elucidate the underlying mechanisms of tDCS using a multimodal approach that extends from behavioral to neurotransmitter levels of explanation. Thirty-two healthy participants performed an auditory dichotic listening task at two visits, one session with sham and one session with real tDCS (2mA) while simultaneously undergoing functional magnetic resonance imaging (fMRI). The anode and cathode were placed over the left temporo-parietal cortex (TPC) and dorsolateral prefrontal cortex, respectively. Before and after simultaneous dichotic listening/fMRI/tDCS, combined glutamate and glutamine (Glx) and myo-inositol levels were assessed in the stimulated areas. While fMRI and dichotic listening showed expected functional activity and behavioral effects, neither method demonstrated differences between real and sham stimulation. Glx only showed a statistical trend towards higher levels after real tDCS in both stimulated brain areas. There were no significant correlations between behavior and Glx. Despite a reasonable sample size, electrical field strength, and replication of behavioral and functional activity results, tDCS had little to no effect on dichotic listening, Glx, and functional activity. The study emphasizes that findings about the underlying neural mechanisms of the primary motor cortex cannot simply be generalized to other brain areas. Particularly, the TPC might be less sensitive to tDCS. Moreover, the study demonstrates the general feasibility of multimodal approaches.

One Tap at a Time: Correlating Sensorimotor Synchronization with Brain Signatures of Temporal Processing.

The ability to integrate our perceptions across sensory modalities and across time, to execute and coordinate movements, and to adapt to a changing environment rests on temporal processing. Timing is essential for basic daily tasks, such as walking, social interaction, speech and language comprehension, and attention. Impaired temporal processing may contribute to various disorders, from attention-deficit hyperactivity disorder and schizophrenia to Parkinson’s disease and dementia. The foundational importance of timing ability has yet to be fully understood; and popular tasks used to investigate behavioral timing ability, such as sensorimotor synchronization (SMS), engage a variety of processes in addition to the neural processing of time. The present study utilizes SMS in conjunction with a separate passive listening task that manipulates temporal expectancy while recording electroencephalographic data. Participants display a larger N1-P2 evoked potential complex to unexpected beats relative to temporally predictable beats, a differential we call the timing response index (TRI). The TRI correlates with performance on the SMS task: better synchronizers show a larger brain response to unexpected beats. The TRI, derived from the perceptually driven N1-P2 complex, disentangles the perceptual and motor components inherent in SMS and thus may serve as a neural marker of a more general temporal processing.

Lateralization of Auditory Processing of Silbo Gomero

Left-hemispheric language dominance is a well-known characteristic of the human language system. However, it has been shown that leftward language lateralization decreases dramatically when people communicate using whistles. Whistled languages present a transformation of a spoken language into whistles, facilitating communication over great distances. In order to investigate the laterality of Silbo Gomero, a form of whistled Spanish, we used a vocal and a whistled dichotic listening task in a sample of 75 healthy Spanish speakers. Both individuals that were able to whistle and to understand Silbo Gomero and a non-whistling control group showed a clear right-ear advantage for vocal dichotic listening. For whistled dichotic listening, the control group did not show any hemispheric asymmetries. In contrast, the whistlers’ group showed a right-ear advantage for whistled stimuli. This right-ear advantage was, however, smaller compared to the right-ear advantage found for vocal dichotic listening. In line with a previous study on language lateralization of whistled Turkish, these findings suggest that whistled language processing is associated with a decrease in left and a relative increase in right hemispheric processing. This shows that bihemispheric processing of whistled language stimuli occurs independent of language.