Semantics, syntax or neither? A case for resolution in the interpretation of N500 and P600 responses to harmonic incongruities

Musical Expertise Reshapes Cross-Domain Semantic Integration: ERP Evidence from Language and Music Processing

Background/Objectives: Both language and music are capable of encoding and communicating semantic concepts, suggesting a potential overlap in neurocognitive mechanisms. Moreover, music training not only enhances domain-specific musical processing but also facilitates cross-domain language processing. However, existing research has predominantly focused on Indo-European languages, with limited evidence from paratactic languages such as Mandarin Chinese. In addition, the impact of variations in musical expertise on these shared processing mechanisms remains unclear, leaving a critical gap in our understanding of the shared neural bases for semantic processing in language and music. This event-related potential (ERP) study investigated whether Chinese sentences and musical chord sequences share semantic processing mechanisms and how musical expertise modulates these mechanisms. Methods: This study recruited 46 college students (22 musicians and 24 non-musicians). Participants read Chinese sentences presented word-by-word visually, while chord sequences were delivered auditorily, with each word temporally aligned to one chord. Sentences included semantically acceptable or unacceptable classifier-noun pairs and chord sequences ended with in-key or out-of-key chords. Participants were instructed to focus on reading sentences while ignoring the concurrent music. ERP signals were recorded, and time-locked to final words to capture neural dynamics during semantic integration. Results: The behavioral results showed that musicians were influenced by musical regularity when reading (acceptable: F(1, 44) = 25.70, p < 0.001, ηp2 = 0.38; unacceptable: F(1, 44) = 11.45, p = 0.002, ηp2 = 0.21), but such effect was absent in non-musicians (ps > 0.05). ERP results showed that musical semantic processing had a substantial impact on both P200 (F(1, 44) = 9.95, p = 0.003, ηp2 = 0.18), N400 (musicians: F(1, 44) = 15.80, p < 0.001, ηp2 = 0.26; non-musicians: F(1, 44) = 4.34, p = 0.043, ηp2 = 0.09), and P600 (musicians: F(1, 44) = 5.55, p = 0.023, ηp2 = 0.11; non-musicians: F(1, 44) = 8.68, p = 0.005, ηp2 = 0.17) components. Furthermore, musical expertise exerted modulatory effects during later stages, as evidenced by divergent N400 and P600 latency patterns between musicians and non-musicians. Specifically, ERP amplitudes exhibited opposing trends: musicians showed an enhanced N400 and diminished P600, while non-musicians displayed a weaker N400 and stronger P600. Conclusions: Our findings provide novel evidence that Mandarin Chinese and chord sequences engage partially overlapping neural mechanisms for semantic processing both in the early (P200) and the late (N400 and P600) stages. Crucially, this study is the first to demonstrate that musical expertise may gradually reorganize these shared mechanisms, enabling two initially independent but functionally analogous semantic mechanisms into a domain-general processing system. These insights deepen our understanding of the neurocognitive mechanisms underlying linguistic and musical semantic processing and highlight how expertise shapes the neural architecture of cross-domain mechanisms.

Linguistic and Musical Syntax Processing in Autistic and Non-Autistic Individuals: An Event-Related Potential (ERP) Study

Syntactic processing in both language and music involves combining elements-such as words or chords-into coherent structures. The Shared Syntactic Integration Resource Hypothesis (SSIRH) was introduced based on observations of similar neural responses to syntactic violations across both domains. This hypothesis suggests that difficulties in syntactic processing in one domain may result in similar challenges in the other. The current study tested the SSIRH in autism, a neurodevelopmental condition often associated with language difficulties but relatively preserved musical abilities. Thirty-one autistic and 31 non-autistic participants judged the acceptability of syntactically congruent and incongruent sentences and musical sequences while their neural responses were recorded using electroencephalography. Autistic participants exhibited a reduced and delayed P600 effect-a marker of syntactic integration-across both domains, despite achieving similar behavioral accuracy to the non-autistic group. These findings suggest parallel difficulties in syntactic processing in autism for both language and music, providing support for the SSIRH. This is the first study to directly examine real-time syntactic integration in both domains in autistic individuals, offering novel insights into cross-domain syntactic processing in autism and contributing to a deeper understanding of language and music processing more broadly.

Auditory associative word learning in adults: The effects of musical experience and stimulus ordering

Evidence for sequential associative word learning in the auditory domain has been identified in infants, while adults have shown difficulties. To better understand which factors may facilitate adult auditory associative word learning, we assessed the role of auditory expertise as a learner-related property and stimulus order as a stimulus-related manipulation in the association of auditory objects and novel labels. We tested in the first experiment auditorily-trained musicians versus athletes (high-level control group) and in the second experiment stimulus ordering, contrasting object-label versus label-object presentation. Learning was evaluated from Event-Related Potentials (ERPs) during training and subsequent testing phases using a cluster-based permutation approach, as well as accuracy-judgement responses during test. Results revealed for musicians a late positive component in the ERP during testing, but neither an N400 (400-800 ms) nor behavioral effects were found at test, while athletes did not show any effect of learning. Moreover, the object-label-ordering group only exhibited emerging association effects during training, while the label-object-ordering group showed a trend-level late ERP effect (800-1200 ms) during test as well as above chance accuracy-judgement scores. Thus, our results suggest the learner-related property of auditory expertise and stimulus-related manipulation of stimulus ordering modulate auditory associative word learning in adults.

Evidence for LoTH: Slim pickings

In this commentary, I contend that a representative sample of the arguments in the target article miss the mark. In particular, the interface problem provides no warrant for positing similarities between representational formats, and the evidence from neurocognitive, animal, and behavioral studies is inconclusive at best. Finally, I raise doubts about whether the authors' central hypothesis is falsifiable.

The effects of contextual certainty on tension induction and resolution

It is known that tension is a core principle of the generation of music emotion and meaning, and supposed to be induced by prediction in process of music listening. Using EEG and behavioral rating, the current research investigated how contextual certainty affects musical tension induction and resolution. The major results were that in the tension induction process, incongruent conditions elicited larger EN and P600 in ERP responses compared with congruent conditions, and the amplitude of P600, tension ratings were mediated by contextual certainty. In the tension resolution process, contextual certainty further affected the duration of P600 and tension ratings. For the certain conditions, tension ratings were higher, tension curves fluctuated faster, and a larger P600 was evoked in the incongruent condition compared with the congruent condition. For the uncertain conditions, there was no congruency effect on behavioral ratings and tension curves, but a larger P600 was elicited in the congruent condition. These results show that contextual certainty affects tension induction and resolution. Our findings provide a more comprehensive view on how musical prediction affects musical tension.

Musical and linguistic syntactic processing in agrammatic aphasia: An ERP study

Language and music rely on complex sequences organized according to syntactic principles that are implicitly understood by enculturated listeners. Across both domains, syntactic processing involves predicting and integrating incoming elements into higher-order structures. According to the Shared Syntactic Integration Resource Hypothesis (SSIRH; Patel, 2003), musical and linguistic syntactic processing rely on shared resources for integrating incoming elements (e.g., chords, words) into unfolding sequences. One prediction of the SSIRH is that people with agrammatic aphasia (whose deficits are due to syntactic integration problems) should present with deficits in processing musical syntax. We report the first neural study to test this prediction: event-related potentials (ERPs) were measured in response to musical and linguistic syntactic violations in a group of people with agrammatic aphasia (n=7) compared to a group of healthy controls (n=14) using an acceptability judgement task. The groups were matched with respect to age, education, and extent of musical training. Violations were based on morpho-syntactic relations in sentences and harmonic relations in chord sequences. Both groups presented with a significant P600 response to syntactic violations across both domains. The aphasic participants presented with a reduced-amplitude posterior P600 compared to the healthy adults in response to linguistic, but not musical, violations. Participants with aphasia did however present with larger frontal positivities in response to violations in both domains. Intriguingly, extent of musical training was associated with larger posterior P600 responses to syntactic violations of language and music in both groups. Overall, these findings are not consistent with the predictions of the SSIRH, and instead suggest that linguistic, but not musical, syntactic processing may be selectively impaired in stroke-induced agrammatic aphasia. However, the findings also suggest a relationship between musical training and linguistic syntactic processing, which may have clinical implications for people with aphasia, and motivates more research on the relationship between these two domains.

Neural Dynamics of Target Detection via Wireless EEG in Embodied Cognition

Embodied cognitive attention detection is important for many real-world applications, such as monitoring attention in daily driving and studying. Exploring how the brain and behavior are influenced by visual sensory inputs becomes a major challenge in the real world. The neural activity of embodied mind cognitive states can be understood through simple symbol experimental design. However, searching for a particular target in the real world is more complicated than during a simple symbol experiment in the laboratory setting. Hence, the development of realistic situations for investigating the neural dynamics of subjects during real-world environments is critical. This study designed a novel military-inspired target detection task for investigating the neural activities of performing embodied cognition tasks in the real-world setting. We adopted independent component analysis (ICA) and electroencephalogram (EEG) dipole source localization methods to study the participant's event-related potentials (ERPs), event-related spectral perturbation (ERSP), and power spectral density (PSD) during the target detection task using a wireless EEG system, which is more convenient for real-life use. Behavioral results showed that the response time in the congruent condition (582 ms) was shorter than those in the incongruent (666 ms) and nontarget (863 ms) conditions. Regarding the EEG observation, we observed N200-P300 wave activation in the middle occipital lobe and P300-N500 wave activation in the right frontal lobe and left motor cortex, which are associated with attention ERPs. Furthermore, delta (1-4 Hz) and theta (4-7 Hz) band powers in the right frontal lobe, as well as alpha (8-12 Hz) and beta (13-30 Hz) band powers in the left motor cortex were suppressed, whereas the theta (4-7 Hz) band powers in the middle occipital lobe were increased considerably in the attention task. Experimental results showed that the embodied body function influences human mental states and psychological performance under cognition attention tasks. These neural markers will be also feasible to implement in the real-time brain computer interface. Novel findings in this study can be helpful for humans to further understand the interaction between the brain and behavior in multiple target detection conditions in real life.

Contextual prediction modulates musical tension: Evidence from behavioral and neural responses

Tension is a bridge between music structure and emotion. It is known that tension is affected by prediction in music listening as music unfolds. Combining behavioral and neural responses, the current research investigated how musical predictions influence tension in the process of prediction build-up based on musical context (anticipatory stage) and its integration with upcoming stimuli (integration stage). The results showed that, at the anticipatory stage, compared with high-prediction conditions, in low-prediction conditions tension curve changed faster and unstable, and a larger N5 in ERP response was elicited. Furthermore, at the integration stage, compared with congruent conditions, in incongruent conditions the behavioral rating of tension were higher regardless of the predictability of the final chord; a right negativity and P600 were elicited, and the amplitude of P600 was modulated by the predictability of the final chord. These results indicated that the effect of prediction on tension was modulated by contextual predictability. The findings provide a more comprehensive view on how musical prediction affects musical tension.

Music, Language, and The N400: ERP Interference Patterns Across Cognitive Domains

Studies of the relationship of language and music have suggested these two systems may share processing resources involved in the computation/maintenance of abstract hierarchical structure (syntax). One type of evidence comes from ERP interference studies involving concurrent language/music processing showing interaction effects when both processing streams are simultaneously perturbed by violations (e.g., syntactically incorrect words paired with incongruent completion of a chord progression). Here, we employ this interference methodology to target the mechanisms supporting long term memory (LTM) access/retrieval in language and music. We used melody stimuli from previous work showing out-of-key or unexpected notes may elicit a musical analogue of language N400 effects, but only for familiar melodies, and not for unfamiliar ones. Target notes in these melodies were time-locked to visually presented target words in sentence contexts manipulating lexical/conceptual semantic congruity. Our study succeeded in eliciting expected N400 responses from each cognitive domain independently. Among several new findings we argue to be of interest, these data demonstrate that: (i) language N400 effects are delayed in onset by concurrent music processing only when melodies are familiar, and (ii) double violations with familiar melodies (but not with unfamiliar ones) yield a sub-additive N400 response. In addition: (iii) early negativities (RAN effects), which previous work has connected to musical syntax, along with the music N400, were together delayed in onset for familiar melodies relative to the timing of these effects reported in the previous music-only study using these same stimuli, and (iv) double violation cases involving unfamiliar/novel melodies also delayed the RAN effect onset. These patterns constitute the first demonstration of N400 interference effects across these domains and together contribute previously undocumented types of interactions to the available pool of findings relevant to understanding whether language and music may rely on shared underlying mechanisms.

Low Arousal Positive Emotional Stimuli Attenuate Aberrant Working Memory Processing in Persons with Mild Cognitive Impairment

Emotional enhancement effects on memory have been reported to mitigate the pathophysiology of Alzheimer's disease (AD). However, relative to their manifestation in persons without pathologic aging, these effects may be reduced in magnitude or even deleterious, especially in tasks that more closely model ecologic memory performance. Based upon a synthesis of such reports, we hypothesized that in persons with AD low arousal positive stimuli would evoke relatively intact emotional enhancement effects, but that high arousal negative stimuli would evoke disordered emotional enhancement effects. To assess this, participants with and without mild cognitive impairment (MCI) presumed to be due to AD performed an emotionally-valenced short-term memory task while encephalography was recorded. Results indicated that for persons with MCI, high arousal negative stimuli led to working memory processing patterns previously associated with MCI presumed due to AD and dementia of the Alzheimer-type. In contrast, low arousal positive stimuli evoked a processing pattern similar to MCI participants' unaffected spouses. Our current findings suggest that low arousal positive stimuli attenuate working memory deficits of MCI due to AD.

Musical training shapes neural responses to melodic and prosodic expectation

Current research on music processing and syntax or semantics in language suggests that music and language share partially overlapping neural resources. Pitch also constitutes a common denominator, forming melody in music and prosody in language. Further, pitch perception is modulated by musical training. The present study investigated how music and language interact on pitch dimension and whether musical training plays a role in this interaction. For this purpose, we used melodies ending on an expected or unexpected note (melodic expectancy being estimated by a computational model) paired with prosodic utterances which were either expected (statements with falling pitch) or relatively unexpected (questions with rising pitch). Participants' (22 musicians, 20 nonmusicians) ERPs and behavioural responses in a statement/question discrimination task were recorded. Participants were faster for simultaneous expectancy violations in the melodic and linguistic stimuli. Further, musicians performed better than nonmusicians, which may be related to their increased pitch tracking ability. At the neural level, prosodic violations elicited a front-central positive ERP around 150 ms after the onset of the last word/note, while musicians presented reduced P600 in response to strong incongruities (questions on low-probability notes). Critically, musicians' P800 amplitudes were proportional to their level of musical training, suggesting that expertise might shape the pitch processing of language. The beneficial aspect of expertise could be attributed to its strengthening effect of general executive functions. These findings offer novel contributions to our understanding of shared higher-order mechanisms between music and language processing on pitch dimension, and further demonstrate a potential modulation by musical expertise.

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Melodic expectancy influences the processing of prosodic expectancy.

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Musical expertise modulates pitch processing in music and language.

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Musicians have a more refined response to pitch.

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Musicians' neural responses are proportional to their level of musical expertise.

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Possible association between the P200 neural component and behavioural facilitation.

Processing structure in language and music: a case for shared reliance on cognitive control

The relationship between structural processing in music and language has received increasing interest in the past several years, spurred by the influential Shared Syntactic Integration Resource Hypothesis (SSIRH; Patel, Nature Neuroscience, 6, 674-681, 2003). According to this resource-sharing framework, music and language rely on separable syntactic representations but recruit shared cognitive resources to integrate these representations into evolving structures. The SSIRH is supported by findings of interactions between structural manipulations in music and language. However, other recent evidence suggests that such interactions also can arise with nonstructural manipulations, and some recent neuroimaging studies report largely nonoverlapping neural regions involved in processing musical and linguistic structure. These conflicting results raise the question of exactly what shared (and distinct) resources underlie musical and linguistic structural processing. This paper suggests that one shared resource is prefrontal cortical mechanisms of cognitive control, which are recruited to detect and resolve conflict that occurs when expectations are violated and interpretations must be revised. By this account, musical processing involves not just the incremental processing and integration of musical elements as they occur, but also the incremental generation of musical predictions and expectations, which must sometimes be overridden and revised in light of evolving musical input.

Language influences music harmony perception: effects of shared syntactic integration resources beyond attention

Many studies have revealed shared music-language processing resources by finding an influence of music harmony manipulations on concurrent language processing. However, the nature of the shared resources has remained ambiguous. They have been argued to be syntax specific and thus due to shared syntactic integration resources. An alternative view regards them as related to general attention and, thus, not specific to syntax. The present experiments evaluated these accounts by investigating the influence of language on music. Participants were asked to provide closure judgements on harmonic sequences in order to assess the appropriateness of sequence endings. At the same time participants read syntactic garden-path sentences. Closure judgements revealed a change in harmonic processing as the result of reading a syntactically challenging word. We found no influence of an arithmetic control manipulation (experiment 1) or semantic garden-path sentences (experiment 2). Our results provide behavioural evidence for a specific influence of linguistic syntax processing on musical harmony judgements. A closer look reveals that the shared resources appear to be needed to hold a harmonic key online in some form of syntactic working memory or unification workspace related to the integration of chords and words. Overall, our results support the syntax specificity of shared music-language processing resources.

Electrophysiological evidence for a specific neural correlate of musical violation expectation in primary-school children

The majority of studies on music processing in children used simple musical stimuli. Here, primary schoolchildren judged the appropriateness of musical closure in expressive polyphone music, while high-density electroencephalography was recorded. Stimuli ended either regularly or contained refined in-key harmonic transgressions at closure. The children discriminated the transgressions well above chance. Regular and transgressed endings evoked opposite scalp voltage configurations peaking around 400ms after stimulus onset with bilateral frontal negativity for regular and centro-posterior negativity (CPN) for transgressed endings. A positive correlation could be established between strength of the CPN response and rater sensitivity (d-prime). We also investigated whether the capacity to discriminate the transgressions was supported by auditory domain specific or general cognitive mechanisms, and found that working memory capacity predicted transgression discrimination. Latency and distribution of the CPN are reminiscent of the N400, typically observed in response to semantic incongruities in language. Therefore our observation is intriguing, as the CPN occurred here within an intra-musical context, without any symbols referring to the external world. Moreover, the harmonic in-key transgressions that we implemented may be considered syntactical as they transgress structural rules. Such structural incongruities in music are typically followed by an early right anterior negativity (ERAN) and an N5, but not so here. Putative contributive sources of the CPN were localized in left pre-motor, mid-posterior cingulate and superior parietal regions of the brain that can be linked to integration processing. These results suggest that, at least in children, processing of syntax and meaning may coincide in complex intra-musical contexts.