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Funding Information: This work received funding from the Academy of Finland (Grant #297848, “Modulation of brain activity patterns during selective attention to speech”, 2016–2021) and the Emil Aaltonen Foundation. The funders had no role in study design, collection, analysis, or interpretation of data, or in the writing of the article. Publisher Copyright: © 2021 The Author(s) Selective listening to speech depends on widespread networks of the brain, but how the involvement of different neural systems in speech processing is affected by factors such as the task performed by a listener and speech intelligibility remains poorly understood. We used functional magnetic resonance imaging to systematically examine the effects that performing different tasks has on neural activations during selective attention to continuous audiovisual speech in the presence of task-irrelevant speech. Participants viewed audiovisual dialogues and attended either to the semantic or the phonological content of speech, or ignored speech altogether and performed a visual control task. The tasks were factorially combined with good and poor auditory and visual speech qualities. Selective attention to speech engaged superior temporal regions and the left inferior frontal gyrus regardless of the task. Frontoparietal regions implicated in selective auditory attention to simple sounds (e.g., tones, syllables) were not engaged by the semantic task, suggesting that this network may not be not as crucial when attending to continuous speech. The medial orbitofrontal cortex, implicated in social cognition, was most activated by the semantic task. Activity levels during the phonological task in the left prefrontal, premotor, and secondary somatosensory regions had a distinct temporal profile as well as the highest overall activity, possibly relating to the role of the dorsal speech processing stream in sub-lexical processing. Our results demonstrate that the task type influences neural activations during selective attention to speech, and emphasize the importance of ecologically valid experimental designs.

Morphemes are defined as the smallest meaningful units of a language. They can, among other things, be used to form new words (i.e., derivation, e.g., -ness in darkness) or convey grammatical information (i.e., inflection, e.g., plural -s in houses). Learning the meaning of morphemes and recognizing morphemic boundaries is thus an essential part of language learning, however, neural mechanisms underlying the acquisition of morphemes remain largely unexplored. Here, we investigated the online build-up of memory traces for novel bound morphemes (suffixes) in the left perisylvian language network. Half of the novel suffixes were trained semantically through a picture-word association task and half were untrained, i.e., not provided with a semantic referent. Following the semantic training with twenty repetitions per suffix, we used magnetoencephalography (MEG) to record cortical responses to the novel semantically trained, novel untrained, and real suffixes combined with real and pseudoword stems in a 20-minute-long repetitive exposure task. The participants were exposed to spoken stimuli passively, i.e., without any stimulus-related task, while their attention was diverted away from the auditory input. To assess the online learning, we compared the brain’s neuromagnetic responses to the different suffixes in the beginning and the end of this passive exposure. Our results showed that semantically trained suffixes demonstrated a consistent activation pattern throughout the learning task, suggesting that repetitive exposure did not further facilitate learning after the formation of initial episodic memories during the semantic training. By contrast, neural source activation to untrained suffixes combined with real stems increased over the course of the passive exposure, reflecting a build-up of suffix-related memory traces. Online learning related changes were present in all regions of interest in the left hemisphere (inferior frontal gyrus, anterior temporal lobe, posterior superior temporal gyrus, posterior middle temporal gyrus. The distinction in the neural source activity patterns between the trained and untrained novel suffix types indicates that semantic information can give a head start to the suffix learning process. Furthermore, in the context of a real word stem, neural source activation elicited by both novel suffix types in the late phase of the passive exposure reached the early phase activation elicited by real suffixes. Our results suggest immediate learning effects to novel suffixes gained through a brief semantic learning as well as more incremental suffix learning effects obtained through purely perceptual exposure.

Recent studies utilizing electrophysiological speech envelope reconstruction have sparked renewed interest in the cocktail party effect by showing that auditory neurons entrain to selectively attended speech. Yet, the neural networks of attention to speech in naturalistic audiovisual settings with multiple sound sources remain poorly understood. We collected functional brain imaging data while participants viewed audiovisual video clips of lifelike dialogues with concurrent distracting speech in the background. Dialogues were presented in a full-factorial design, comprising task (listen to the dialogues vs. ignore them), audiovisual quality and semantic predictability. We used univariate analyses in combination with multivariate pattern analysis (MVPA) to study modulations of brain activity related to attentive processing of audiovisual speech. We found attentive speech processing to cause distinct spatiotemporal modulation profiles in distributed cortical areas including sensory and frontal-control networks. Semantic coherence modulated attention-related activation patterns in the earliest stages of auditory cortical processing, suggesting that the auditory cortex is involved in high-level speech processing. Our results corroborate views that emphasize the dynamic nature of attention, with task-specificity and context as cornerstones of the underlying neuro-cognitive mechanisms.

Formation of neural mechanisms for morphosyntactic processing in young children is still poorly understood. Here, we addressed neural processing and rapid online acquisition of familiar and unfamiliar combinations of morphemes. Three different types of morphologically complex words - derived, inflected, and novel (pseudostem + real suffix) - were presented in a passive listening setting to 16 typically developing 3-4-year old children (as part of a longitudinal Helsinki SLI follow-up study). The mismatch negativity (MMN) component of event-related potentials (ERP), an established index of long-term linguistic memory traces in the brain, was analysed separately for the initial and final periods of the exposure to these items. We found MMN response enhancement for the inflected words towards the end of the recording session, whereas no response change was observed for the derived or novel complex forms. This enhancement indicates rapid build-up of a new memory trace for the combination of real morphemes, suggesting a capacity for online formation of whole-form lexicalized representations as one of the morphological mechanisms in the developing brain. Furthermore, this enhancement increased with age, suggesting the development of automatic morphological processing circuits in the age range of 3-4 years.

International audience; Dual language experience has typically been shown to improve various executive control functions. We investigated with event-related brain potentials (ERPs) recorded from early (natively) bilingual speakers and control participants whether it also affects auditory selective attention. We delivered to our participants two tone streams, one to the left and one to the right ear. Both streams consisted of standard tones and two types of infrequent deviant tones which had either an enhanced duration or intensity. The participants were instructed to attend either to the right or left stream and to detect longer-duration deviants in the attended stream. The results showed that the early bilinguals did not outperform the controls in target detection accuracy or speed. However, the late portion of the attention-related ERP modulation (the negative difference, Nd) was larger over the left hemisphere in the early bilinguals than in the controls, suggesting that the maintenance of selective attention or further processing of selectively attended sounds is enhanced in the bilinguals. Moreover, the late reorienting negativity (RON) in response to intensity-deviant tones was larger in the bilinguals, suggesting more efficient disengagement of attention from distracting auditory events. Hence, our results demonstrate that brain responses associated with certain aspects of auditory attention are enhanced in the bilingual adults, indicating that early dual language exposure modulates the neuronal responsiveness of auditory modality.

We investigated neural distinctions between inflectional and derivational morphology and their interaction with lexical frequency using the mismatch negativity (MMN), an established neurophysiological index of experience-dependent linguistic memory traces and automatic syntactic processing. We presented our electroencephalography (EEG) study participants with derived and inflected words of variable lexical frequencies against their monomorphemic base forms in a passive oddball paradigm, along with acoustically matched pseudowords. Sensor space and distributed source modelling results showed that at 100-150 msec after the suffix onset, derived words elicited larger responses than inflected words. Furthermore, real derived words showed advantage over pseudo-derivations and frequent derivations elicited larger activation than less frequent ones. This pattern of results is fully in line with previous research that explained lexical MMN enhancement by an activation of strongly connected word-specific long-term memory circuits, and thus suggests stronger lexicalisation for frequently used complex words. At the same time, a strikingly different pattern was found for inflectional forms: higher response amplitude for pseudo-inflections than for real inflected words, with no clear frequency effects. This is fully in line with previous MMN results on combinatorial processing of (morpho)syntactic stimuli: higher response to ungrammatical morpheme strings than grammatical ones, which does not depend on the string's surface frequency. This pattern suggests that, for inflectional forms, combinatorial processing route dominates over whole-form storage and access. In sum, our results suggest that derivations are more likely to form unitary representations than inflections which are likely to be processed combinatorially, and imply at least partially distinct brain mechanisms for the processing and representation of these two types of morphology. These dynamic mechanisms, underpinned by perisylvian networks, are activated rapidly, at 100-150 msec after the information arrives at the input, and in a largely automatic fashion, possibly providing neural basis for the first-pass morphological processing of spoken words.

Introduction: Slow-wave sleep (SWS) slow waves and sleep spindle activity have been shown to be crucial for memory consolidation. Recently, memory consolidation has been causally facilitated in human participants via auditory stimuli phase-locked to SWS slow waves. Aims: Here, we aimed to develop a new acoustic stimulus protocol to facilitate learning and to validate it using different memory tasks. Most importantly, the stimulation setup was automated to be applicable for ambulatory home use. Methods: Fifteen healthy participants slept 3 nights in the laboratory. Learning was tested with 4 memory tasks (word pairs, serial finger tapping, picture recognition, and face-name association). Additional questionnaires addressed subjective sleep quality and overnight changes in mood. During the stimulus night, auditory stimuli were adjusted and targeted by an unsupervised algorithm to be phase-locked to the negative peak of slow waves in SWS. During the control night no sounds were presented. Results: Results showed that the sound stimulation increased both slow wave (p = .002) and sleep spindle activity (p < .001). When overnight improvement of memory performance was compared between stimulus and control nights, we found a significant effect in word pair task but not in other memory tasks. The stimulation did not affect sleep structure or subjective sleep quality. Conclusions: We showed that the memory effect of the SWS-targeted individually triggered single-sound stimulation is specific to verbal associative memory. Moreover, the ambulatory and automated sound stimulus setup was promising and allows for a broad range of potential follow-up studies in the future.

How is morphological and morphosyntactic information processed during sentence reading? Are the neural mechanisms underlying word- and phrase-level combinatorial processing overlapping or distinct? Here, electroencephalography (EEG) and magnetoencephalography (MEG) responses were recorded simultaneously during silent reading of Finnish sentences. The experimental conditions included 1) well-formed grammatical sentences (correct condition), 2) sentences containing morphosyntactic violations (adjective–noun number agreement violations), 3) morphological violations (incorrect stem allomorph and inflectional suffix combination), and 4) combined violations, containing both morphosyntactic and morphological violations. Signal space and source modeling results showed that morphosyntactic violations elicited a left anterior negativity effect, generated particularly in the left inferior frontal area. Morphological violations elicited a widespread negativity, resembling the N400. The neural sources of this negativity were localized most prominently to the right temporal cortical networks. Furthermore, all violations elicited P600 effects with similar widespread bilateral fronto-temporal neural generators that did not differ between morphosyntactic and morphological conditions. Our findings suggest at least partially distinct subnetworks in the fronto-temporal cortices for morphological and morphosyntactic parsing during the earlier stages of processes (∼400 ms post stimulus onset) and shared neural generators for the later processing stages.

Objective The aim was to study how the measurement error affects the repeatability of mismatch negativity (MMN) measurements. Methods Event-related potentials (ERPs) to changes in sound frequency, location, intensity, duration, and composition were recorded five times during 1–3 weeks from 13 healthy adults using a multi-feature MMN paradigm. The accumulation of MMN was modeled empirically with respect to measurement error, and repeatability was estimated at 0.6–3.5-μV error levels. The analysis was made for the results in the single deviant conditions and their pattern (auditory discrimination profile). Results At the single-subject level, the measurement error significantly affected the repeatability until it went below 9–17% of MMN peak amplitude. At the group level, the threshold was higher. Peak amplitude was generally the most repeatable parameter. Latency was superior when the error was moderate or small ( Conclusions The measurement error affects the repeatability of MMN. In single-subject studies, it should not be neglected if it exceeds 10% of the MMN amplitude. The application of the auditory discrimination profile is recommended for future applications. Significance The study provided quantitative results to support the discussion on improving the repeatability of the MMN measurements. They are expected to apply conditionally to other ERP measurements, too.

Research into neurobiological mechanisms of morphosyntactic processing of language has suggested specialised systems for decomposition and storage, which are used flexibly during the processing of complex polymorphemic words (such as those formed through affixation, e.g., boy + s = noun + plural marker or boy + ish = noun plus attenuator). However, neural underpinnings of acquisition of novel morphology are still unknown. We implicitly trained our participants with new derivational affixes through a word-picture association task and investigated the neural processes underlying formation of neural memory traces for new affixes. The participants' brain activity was recorded using magnetoencephalography (MEG), as they passively listened to the newly trained and untrained suffixes combined with real word and pseudoword stems. The MEG recording was repeated after a night's sleep using the same stimuli, to test the effects of overnight consolidation. The newly trained suffixes combined with real stems elicited stronger source activity in the left inferior frontal gyrus (LIFG) at ∼50 msec after the suffix onset than untrained suffixes, suggesting memory trace formation for the newly learned suffixes already on the same day. The following day, the suffix learning effect spread to the left superior temporal gyrus (STG) where it was again manifest as a response enhancement, particularly at ∼200-300 msec after the suffix onset, which might reflect an additional effect of overnight consolidation. Overall, the results demonstrate the rapid and dynamic processes of both immediate build-up and longer-term consolidation of neocortical memory traces for novel morphology, taking place after a short period of exposure to novel morphology and involving fronto-temporal perisylvian language circuitry.

The present study investigates age-related changes in duration discrimination in millisecond time domain. We tested young (N = 20, mean age = 24.5, SD = 2.97) and elderly (N = 20, mean age = 65.2, SD = 2.94) subjects using the mismatch negativity (MMN) paradigm. White-noise bursts of two different durations (50 and 10 ms) were presented in two oddball blocks. In one block (Increment Condition), the repetitive sequence of 10 ms standards was interspersed by occasional 50 ms deviants. In the Decrement Condition, the roles of the two stimuli were reversed. We analyzed the P1-N1 complex, MMN and P3a and found the effect of age for all these components. Moreover, the impact of stimulus presentation condition (increment/decrement) was observed for MMN and P3a. Our results confirmed the previous evidence for deteriorated duration discrimination in elderly people. Additionally, we found that this effect may be influenced by procedural factors.

Informal music activities such as singing may lead to augmented auditory perception and attention. In order to study the accuracy and development of music-related sound change detection in children with cochlear implants (CIs) and normal hearing (NH) aged 4-13 years, we recorded their auditory event-related potentials twice (at T1 and T2, 14-17 months apart). We compared their MMN (preattentive discrimination) and P3a (attention towards salient sounds) to changes in piano tone pitch, timbre, duration, and gaps. Of particular interest was to determine whether singing can facilitate auditory perception and attention of CI children. It was found that, compared to the NH group, the CI group had smaller and later timbre P3a and later pitch P3a, implying degraded discrimination and attention shift. Duration MMN became larger from T1 to T2 only in the NH group. Duration MMN became larger from T1 to T2 only in the NH group. The development of response patterns for duration and gap changes were not similar in the CI and NH groups. Importantly, CI singers had enhanced or rapidly developing P3a or P3a-like responses over all change types. In contrast, CI non-singers had rapidly enlarging pitch MMN without enlargement of P3a, and their timbre P3a became smaller and later over time. These novel results show interplay between MMN, P3a, brain development, cochlear implantation and singing. They imply an augmented development of neural networks for attention and more accurate neural discrimination associated with singing. In future studies, differential development of P3a between CI and NH children should be taken into account in comparisons of these groups. Moreover, further studies are needed to assess whether singing enhances auditory perception and attention of children with CIs.

Hazard and risk perception has been studied extensively among car drivers, and their link to crash involvement is established. Bicyclists, in particular, are vulnerable road users. Better understanding of their risk and hazard perception could help to improve their traffic safety. In this study, we investigated the risk perception of bicyclists in a city environment. Two groups of bicyclists were compared: 19 frequent and 19 infrequent bicyclists. Participants were shown video clips taken with a camera attached to the handlebar of a bicycle, and they were asked to continuously indicate with a slider how much caution the situation needed. The frequent cyclists had more frequent rises in the caution estimate, which suggest that they anticipated or detected more hazards than infrequent cyclists. This is in line with the classical hazard perception results, which link the car driving experience to faster and more accurate hazard perception. The overall level or caution was not directly related to the rise event rate or bicycling frequency. Those cyclists who reported typically cycling faster than others showed elevated overall level of caution on sidewalks compared with others, but there was no difference on bike paths. Hazard and risk perception has been studied extensively among car drivers, and their link to crash involvement is established. Bicyclists, in particular, are vulnerable road users. Better understanding of their risk and hazard perception could help to improve their traffic safety. In this study, we investigated the risk perception of bicyclists in a city environment. Two groups of bicyclists were compared: 19 frequent and 19 infrequent bicyclists. Participants were shown video clips taken with a camera attached to the handlebar of a bicycle, and they were asked to continuously indicate with a slider how much caution the situation needed. The frequent cyclists had more frequent rises in the caution estimate, which suggest that they anticipated or detected more hazards than infrequent cyclists. This is in line with the classical hazard perception results, which link the car driving experience to faster and more accurate hazard perception. The overall level or caution was not directly related to the rise event rate or bicycling frequency. Those cyclists who reported typically cycling faster than others showed elevated overall level of caution on sidewalks compared with others, but there was no difference on bike paths. (C) 2015 Elsevier Ltd. All rights reserved.

The spatiotemporal dynamics of the neural processing of spoken morphologically complex words are still an open issue. In the current study, we investigated the time course and neural sources of spoken inflected and derived words using simultaneously recorded electroencephalography (EEG) and magnetoencephalography (MEG) responses. Ten participants (native speakers) listened to inflected, derived, and monomorphemic Finnish words and judged their acceptability. EEG and MEG responses were time-locked to both the stimulus onset and the critical point (suffix onset for complex words, uniqueness point for monomorphemic words). The ERP results showed that inflected words elicited a larger left-lateralized negativity than derived and monomorphemic words approximately 200 ms after the critical point. Source modeling of MEG responses showed one bilateral source in the superior temporal area ∼100 ms after the critical point, with derived words eliciting stronger source amplitudes than inflected and monomorphemic words in the right hemisphere. Source modeling also showed two sources in the temporal cortex approximately 200 ms after the critical point. There, inflected words showed a more systematic pattern in source locations and elicited temporally distinct source activity in comparison to the derived word condition. The current results provide electrophysiological evidence for at least partially distinct cortical processing of spoken inflected and derived words. In general, the results support models of morphological processing stating that during the recognition of inflected words, the constituent morphemes are accessed separately. With regard to derived words, stem and suffix morphemes might be at least initially activated along with the whole word representation.

Event-related potentials were recorded to examine the time course of the neural processing of spoken (i) existing derived words, (ii) morphologically legal, and (iii) illegal pseudowords in the Finnish language. The stimuli were matched by (complex) uniqueness/deviation points and event-related potentials were time-locked to stimulus onset and suffix onset. Illegal pseudowords elicited a larger negativity than existing words approximately 300 ms after suffix onset, suggesting a difficulty to semantically integrate morphemes. The magnitude of the negativity effect was similar for legal pseudowords and existing words, reflecting successful licensing and integration of morphemes for legal pseudowords. The results suggest parallel full-form and morpheme-based processing of spoken derived stimuli and emphasize the role of semantic interpretability in morphological parsing.

A compact (96 x 128 x 32 mm(3), 374 g), battery-powered, eight-channel electroencephalogram recording device with an integrated audio stimulation system and a wireless interface is presented. The recording device is capable of producing high-quality data, while the operating time is also reasonable for evoked potential studies. The effective measurement resolution is about 4 nV at 200 Hz sample rate, typical noise level is below 0.7 microV(rms) at 0.16-70 Hz, and the estimated operating time is 1.5 h. An embedded audio decoder circuit reads and plays wave sound files stored on a memory card. The activities are controlled by an 8 bit main control unit which allows accurate timing of the stimuli. The interstimulus interval jitter measured is less than 1 ms. Wireless communication is made through bluetooth and the data recorded are transmitted to an external personal computer (PC) interface in real time. The PC interface is implemented with LABVIEW and in addition to data acquisition it also allows online signal processing, data storage, and control of measurement activities such as contact impedance measurement, for example. The practical application of the device is demonstrated in mismatch negativity experiment with three test subjects.

Reliable measurements are mandatory in clinically relevant auditory event-related potential (AERP)-based tools and applications. The comparability of the results gets worse as a result of variations in the remaining measurement error. A potential method is studied that allows optimization of the length of the recording session according to the concurrent quality of the recorded data. In this way, the sufficiency of the trials can be better guaranteed, which enables control of the remaining measurement error. The suggested method is based on monitoring the signal-to-noise ratio (SNR) and remaining measurement error which are compared to predefined threshold values. The SNR test is well defined, but the criterion for the measurement error test still requires further empirical testing in practice. According to the results, the reproducibility of average AERPs in repeated experiments is improved in comparison to a case where the number of recorded trials is constant. The test-retest reliability is not significantly changed on average but the between-subject variation in the value is reduced by 33–35%. The optimization of the number of trials also prevents excessive recordings which might be of practical interest especially in the clinical context. The efficiency of the method may be further increased by implementing online tools that improve data consistency.

Learning a new language requires the acquisition of morphological units that enable the fluent use of words in different grammatical contexts. While accumulating research has elucidated the neural processing of native morphology, much less is known about how second-language (L2) learners acquire and process morphology in their L2. To address this question, we presented native speakers as well as beginning and advanced learners of Finnish with spoken (1) derived words, (2) inflected words, (3) novel derivations (novel combinations of existing stem + suffix), and (4) pseudo-suffixed words (existing stem + pseudo-suffix) in a passive listening EEG experiment. An early (60 msec after suffix deviation point) positive ERP response showed no difference between inflections and derivations, suggesting similar early parsing of these complex words. At 130 msec, derivations elicited a lexical ERP pattern of full-form memory-trace activation, present in the L2 beginners and advanced speakers to different degrees, implying a shift from lexical processing to more dual parsing and lexical activation of the complex forms with increasing proficiency. Pseudo-suffixed words produced a syntactic pattern in a later, 170 240 msec time-window, exhibiting enhanced ERPs compared to well-formed inflections, indicating second-pass syntactic parsing. Overall, the L2 learners demonstrated a gradual effect of proficiency towards L1-like responses. Advanced L2 learners seem to have developed memory traces for derivations and their neurolinguistic system is capable of early automatic parsing. This suggests that advanced learners have already developed sensitivity to morphological information, while such knowledge is weak in beginners. Discrepancies in ERP dynamics and topographies indicate partially differing recruitment of the language network in L1 and L2. In beginners, response differences between existing and novel morphology were scarce, implying that representations for complex forms are not yet well-established. The results suggest successful development of brain mechanisms for automatic processing of L2 morphology, capable of gradually attaining L1-like functionality with increasing proficiency. (C) 2019 The Authors. Published by Elsevier Ltd.