Abstract Although there is strong evidence for the positive effects of musical training on auditory perception, processing, and training‐induced neuroplasticity, there is still little knowledge on the auditory and neurophysiological short‐term plasticity through listening training. In a sample of 37 adolescents (20 musicians and 17 nonmusicians) that was compared to a control group matched for age, gender, and musical experience, we conducted a 2‐week active listening training (AULOS: Active IndividUalized Listening OptimizationS). Using magnetoencephalography and psychoacoustic tests, the short‐term plasticity of auditory evoked fields and auditory skills were examined in a pre‐post design, adapted to the individual neuro‐auditory profiles. We found bilateral, but more pronounced plastic changes in the right auditory cortex. Moreover, we observed synchronization of the auditory evoked P1, N1, and P2 responses and threefold larger amplitudes of the late P2 response, similar to the reported effects of musical long‐term training. Auditory skills and thresholds benefited largely from the AULOS training. Remarkably, after training, the mean thresholds improved by 12 dB for bone conduction and by 3–4 dB for air conduction. Thus, our findings indicate a strong positive influence of active listening training on neural auditory processing and perception in adolescence, when the auditory system is still developing.
Recent research has shown that the morphology of certain brain regions may indeed correlate with a number of cognitive skills such as musicality or language ability. The main aim of the present study was to explore the extent to which foreign language aptitude, in particular phonetic coding ability, is influenced by the morphology of Heschl's gyrus (HG; auditory cortex), working memory capacity, and musical ability. In this study, the auditory cortices of German-speaking individuals (N=30; 13m/17f; aged 20-40 y) with high and low scores in a number of language aptitude tests were compared. The subjects' language aptitude was measured by three different tests, namely a Hindi speech imitation task (phonetic coding ability), an English pronunciation assessment, and the Modern Language Aptitude Test (MLAT). Furthermore, working memory capacity and musical ability were assessed to reveal their relationship with foreign language aptitude. On the behavioural level, significant correlations were found between phonetic coding ability, English pronunciation skills, musical experience, and language aptitude as measured by the MLAT. Parts of all three tests measuring language aptitude correlated positively and significantly with each other, supporting their validity for measuring components of language aptitude. Remarkably, the number of instruments played by subjects showed significant correlations with all language aptitude measures and musicality, whereas, the number of foreign languages did not show any correlations. With regard to the neuroanatomy of auditory cortex, adults with very high scores in the Hindi testing and the musicality test (AMMA) demonstrated a clear predominance of complete posterior HG duplications in the right hemisphere. This may reignite the discussion of the importance of the right hemisphere for language processing, especially when linked or common resources are involved, such as the inter-dependency between phonetic and musical aptitude.
Language is a key human faculty for communication and interaction that provides invaluable insight into the human mind. Previous work has dissected different linguistic operations, but the large-scale brain networks involved in language processing are still not fully uncovered. Particularly, little is known about the subdomain-specific engagement of brain areas during semantic, syntactic, phonological, and prosodic processing and the role of subcortical and cerebellar areas. Here, we present the largest coordinate-based meta-analysis of language processing including 403 experiments. Overall, language processing primarily engaged bilateral fronto-temporal cortices, with the highest activation likelihood in the left posterior inferior frontal gyrus (IFG). Whereas we could not detect any syntax-specific regions, semantics specifically engaged left posterior temporal areas (left fusiform and occipitotemporal cortex) and the left frontal pole. Phonology showed highest subdomain-specificity in bilateral auditory and left postcentral regions, whereas prosody engaged specifically the right amygdala and the right IFG. Across all subdomains and modalities, we found strong bilateral subcortical and cerebellar contributions. Especially the right cerebellum was engaged during various processes, including speech production, visual, and phonological tasks. Collectively, our results emphasize consistent recruitment and high functional modularity for general language processing in bilateral domain-specific (temporo-frontal) and domain-general (medial frontal/anterior cingulate cortex) regions but also a high specialization of different subareas for different linguistic subdomains. Our findings refine current neurobiological models of language by adding novel insight into the general sensitivity of the language network and subdomain-specific functions of different brain areas and highlighting the role of subcortical and cerebellar regions for different language operations. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
Non-invasive brain stimulation (NIBS) has gained increasing popularity as a modulatory tool for drawing causal inferences and exploring task-specific network interactions. Yet, a comprehensive synthesis of reading-related NIBS studies is still missing. We fill this gap by synthesizing the results of 78 NIBS studies investigating the causal involvement of brain regions for reading processing, and then link these results to a neurobiological model of reading. The included studies provide evidence for a functional-anatomical double dissociation for phonology versus semantics during reading-related processes within left inferior frontal and parietal areas. Additionally, the posterior parietal cortex and the anterior temporal lobe are identified as critical regions for reading-related processes. Overall, the findings provide some evidence for a dual-stream neurobiological model of reading, in which a dorsal stream (left temporo-parietal and inferior frontal areas) processes unfamiliar words and pseudowords, and a ventral stream (left occipito-temporal and inferior frontal areas, with assistance from the angular gyrus and the anterior temporal lobe) processes known words. However, individual differences in reading abilities and strategies, as well as differences in stimulation parameters, may impact the neuromodulatory effects induced by NIBS. We emphasize the need to investigate task-specific network interactions in future studies by combining NIBS with neuroimaging.
In this chapter, we aim to provide a solid review of studies on the neurobiology of language aptitude and the role of two other important variables, namely musicality and working memory. We stress the importance of taking findings from the cognitive neurosciences into consideration and extend current models on language aptitude by taking neurocognitive perspectives into account. We highlight the importance of stable anatomical and functional markers for individual differences in language learning and aptitude and suggest more closely investigating the interdependency between musical abilities, musical training and language learning. While we argue that working memory is an essential prerequisite for language learning and is largely genetically driven, we propose to include musical abilities in a cognitive starter kit for language aptitude.
Semantic knowledge is central to human cognition. The angular gyrus (AG) is widely considered a key brain region for semantic cognition. However, the role of the AG in semantic processing is controversial. Key controversies concern response polarity (activation vs. deactivation) and its relation to task difficulty, lateralization (left vs. right AG), and functional-anatomical subdivision (PGa vs. PGp subregions). Here, we combined the fMRI data of five studies on semantic processing (n = 172) and analyzed the response profiles from the same anatomical regions-of-interest for left and right PGa and PGp. We found that the AG was consistently deactivated during non-semantic conditions, whereas response polarity during semantic conditions was inconsistent. However, the AG consistently showed relative response differences between semantic and non-semantic conditions, and between different semantic conditions. A combined analysis across all studies revealed that AG responses could be best explained by separable effects of task difficulty and semantic processing demand. Task difficulty effects were stronger in PGa than PGp, regardless of hemisphere. Semantic effects were stronger in left than right AG, regardless of subregion. These results suggest that the AG is engaged in both domain-general task-difficulty-related processes and domain-specific semantic processes. In semantic processing, we propose that left AG acts as a "multimodal convergence zone" that binds different semantic features associated with the same concept, enabling efficient access to task-relevant features.