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In recent years, EEG-based emotion recognition technology has made progress, but there are still problems of low model efficiency and loss of emotional information, and there is still room for improvement in recognition accuracy. To fully utilize EEG's emotional information and improve recognition accuracy while reducing computational costs, this paper proposes a Convolutional-Recurrent Hybrid Network with a dual-stream adaptive approach and an attention mechanism (CSA-SA-CRTNN). Firstly, the model utilizes a CSAM module to assign corresponding weights to EEG channels. Then, an adaptive dual-stream convolutional-recurrent network (SA-CRNN and MHSA-CRNN) is applied to extract local spatial-temporal features. After that, the extracted local features are concatenated and fed into a temporal convolutional network with a multi-head self-attention mechanism (MHSA-TCN) to capture global information. Finally, the extracted EEG information is used for emotion classification. We conducted binary and ternary classification experiments on the DEAP dataset, achieving 99.26% and 99.15% accuracy for arousal and valence in binary classification and 97.69% and 98.05% in ternary classification, and on the SEED dataset, we achieved an accuracy of 98.63%, surpassing relevant algorithms. Additionally, the model's efficiency is significantly higher than other models, achieving better accuracy with lower resource consumption.

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The involvement of the right hemisphere, mainly the activation of the right cerebral regions, in recovery from post-stroke aphasia has been widely recognized. In contrast, the role of the right white matter pathways in the recovery from post-stroke aphasia is rarely understood. In this study, we aimed to provide a primary overview of the correlation between the structural integrity of the right hemispheric neural tracts based on the dual-stream model of language organization and recovery from post-stroke aphasia by systematically reviewing prior longitudinal interventional studies. By searching electronic databases for relevant studies according to a standard protocol, a total of 10 records (seven group studies and three case studies) including 79 participants were finally included. After comprehensively analyzing these studies and reviewing the literature, although no definite correlation was found between the right hemispheric neural tracts and recovery from post-stroke aphasia, our review provideds a new perspective for investigating the linguistic role of the right hemispheric neural tracts. This suggests that the involvement of the right hemispheric neural tracts in recovery from post-stroke aphasia may be mediated by multiple factors; thus, this topic should be comprehensively investigated in the future.

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Timbre is a central aspect of music that allows listeners to identify musical sounds and conveys musical emotion, but also allows for the recognition of actions and is an important structuring property of music. The former functions are known to be implemented in a ventral auditory stream in processing musical timbre. While the latter functions are commonly attributed to areas in a dorsal auditory processing stream in other musical domains, its involvement in musical timbre processing is so far unknown. To investigate if musical timbre processing involves both dorsal and ventral auditory pathways, we carried out an activation likelihood estimation (ALE) meta-analysis of 18 experiments from 17 published neuroimaging studies on musical timbre perception. We identified consistent activations in Brodmann areas (BA) 41, 42, and 22 in the bilateral transverse temporal gyri, the posterior superior temporal gyri and planum temporale, in BA 40 of the bilateral inferior parietal lobe, in BA 13 in the bilateral posterior Insula, and in BA 13 and 22 in the right anterior insula and superior temporal gyrus. The vast majority of the identified regions are associated with the dorsal and ventral auditory processing streams. We therefore propose to frame the processing of musical timbre in a dual-stream model. Moreover, the regions activated in processing timbre show similarities to the brain regions involved in processing several other fundamental aspects of music, indicating possible shared neural bases of musical timbre and other musical domains.

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Numerous studies have been devoted to neural mechanisms of a variety of linguistic tasks (e.g. speech comprehension and production). To date, however, whether and how the neural patterns underlying different linguistic tasks are similar or differ remains elusive. In this study, we compared the neural patterns underlying 3 linguistic tasks mainly concerning speech comprehension and production. To address this, multivariate regression approaches with lesion/disconnection symptom mapping were applied to data from 216 stroke patients with damage to the left hemisphere. The results showed that lesion/disconnection patterns could predict both poststroke scores of speech comprehension and production tasks; these patterns exhibited shared regions on the temporal pole of the left hemisphere as well as unique regions contributing to the prediction for each domain. Lower scores in speech comprehension tasks were associated with lesions/abnormalities in the superior temporal gyrus and middle temporal gyrus, while lower scores in speech production tasks were associated with lesions/abnormalities in the left inferior parietal lobe and frontal lobe. These results suggested an important role of the ventral and dorsal stream pathways in speech comprehension and production (i.e. supporting the dual stream model) and highlighted the applicability of the novel multivariate disconnectome-based symptom mapping in cognitive neuroscience research.

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Congenital cleft lip and palate is one of the common deformities in the craniomaxillofacial region. The current study aimed to explore the perceptual pattern of cleft-related speech produced by Mandarin-speaking patients with repaired cleft palate using the task-based functional magnetic resonance imaging (task-fMRI) technique. Three blocks of speech stimuli, including hypernasal speech, the glottal stop, and typical speech, were played to 30 typical adult listeners with no history of cleft palate speech exploration. Using a randomized block design paradigm, the participants were instructed to assess the intelligibility of the stimuli. Simultaneously, fMRI data were collected. Brain activation was compared among the three types of speech stimuli. Results revealed that greater blood-oxygen-level-dependent (BOLD) responses to the cleft-related glottal stop than to typical speech were localized in the right fusiform gyrus and the left inferior occipital gyrus. The regions responding to the contrast between the glottal stop and cleft-related hypernasal speech were located in the right fusiform gyrus. More significant BOLD responses to hypernasal speech than to the glottal stop were localized in the left orbital part of the inferior frontal gyrus and middle temporal gyrus. More significant BOLD responses to typical speech than to the glottal stop were localized in the left inferior temporal gyrus, left superior temporal gyrus, left medial superior frontal gyrus, and right angular gyrus. Furthermore, there was no significant difference between hypernasal speech and typical speech. In conclusion, the typical listener would initiate different neural processes to perceive cleft-related speech. Our findings lay a foundation for exploring the perceptual pattern of patients with repaired cleft palate.

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Human brain function is an increasingly complex framework that has important implications in clinical medicine. In this review, the anatomy of the most commonly assessed brain functions in clinical neuroradiology, including motor, language, and vision, is discussed. The anatomy and function of the primary and secondary sensorimotor areas are discussed with clinical case examples. Next, the dual stream of language processing is reviewed, as well as its implications in clinical medicine and surgical planning. Last, the authors discuss the striate and extrastriate visual cortex and review the dual stream model of visual processing.

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The arcuate fasciculus has been considered a major dorsal fronto-temporal white matter pathway linking frontal language production regions with auditory perception in the superior temporal gyrus, the so-called Wernicke's area. In line with this tradition, both historical and contemporary models of language function have assigned primacy to superior temporal projections of the arcuate fasciculus. However, classical anatomical descriptions and emerging behavioural data are at odds with this assumption. On one hand, fronto-temporal projections to Wernicke's area may not be unique to the arcuate fasciculus. On the other hand, dorsal stream language deficits have been reported also for damage to middle, inferior and basal temporal gyri that may be linked to arcuate disconnection. These findings point to a reappraisal of arcuate projections in the temporal lobe. Here, we review anatomical and functional evidence regarding the temporal cortical terminations of the left arcuate fasciculus by incorporating dissection and tractography findings with stimulation data using cortico-cortical evoked potentials and direct electrical stimulation mapping in awake patients. First, we discuss the fibres of the arcuate fasciculus projecting to the superior temporal gyrus and the functional rostro-caudal gradient in this region where both phonological encoding and auditory-motor transformation may be performed. Caudal regions within the temporoparietal junction may be involved in articulation and associated with temporoparietal projections of the third branch of the superior longitudinal fasciculus, while more rostral regions may support encoding of acoustic phonetic features, supported by arcuate fibres. We then move to examine clinical data showing that multimodal phonological encoding is facilitated by projections of the arcuate fasciculus to superior, but also middle, inferior and basal temporal regions. Hence, we discuss how projections of the arcuate fasciculus may contribute to acoustic (middle-posterior superior and middle temporal gyri), visual (posterior inferior temporal/fusiform gyri comprising the visual word form area) and lexical (anterior-middle inferior temporal/fusiform gyri in the basal temporal language area) information in the temporal lobe to be processed, encoded and translated into a dorsal phonological route to the frontal lobe. Finally, we point out surgical implications for this model in terms of the prediction and avoidance of neurological deficit.

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The Wernicke-Lichtheim-Geschwind model of the neurology of language has served the field well despite its limited scope. More recent work has updated the basic architecture of the classical model and expanded its scope. This chapter briefly reviews the Wernicke-Lichtheim-Geschwind model and points out its shortcomings, then describes and motivates the dual stream model and how it solves several empirical shortcomings of the classical model. The chapter also (i) underscores how the dual stream model relates to the organization of nonlinguistic cortical networks, integrating language systems with the broader functional-anatomical landscape, (ii) describes recent work that further specifies the computational architecture and neural correlates of the dorsal speech production system, and (iii) summarizes recent extensions of the architectural framework to include syntax.

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OBJECTIVE: This study investigates the clinical course of recovery of apraxia after left-hemisphere stroke and the underlying neuroanatomical correlates for persisting or recovering deficits in relation to the major processing streams in the network for motor cognition. METHODS: 90 patients were examined during the acute (4.74 ± 2.73 days) and chronic (14.3 ± 15.39 months) stage after left-hemisphere stroke for deficits in meaningless imitation, as well as production and conceptual errors in tool use pantomime. Lesion correlates for persisting or recovering deficits were analyzed with an extension of the non-parametric Brunner-Munzel rank-order test for multi-factorial designs (two-way repeated-measures ANOVA) using acute images. RESULTS: Meaningless imitation and tool use production deficits persisted into the chronic stage. Conceptual errors in tool use pantomime showed an almost complete recovery. Imitation errors persisted after occipitotemporal and superior temporal lesions in the dorso-dorsal stream. Chronic pantomime production errors were related to the supramarginal gyrus, the key structure of the ventro-dorsal stream. More anterior lesions in the ventro-dorsal stream (ventral premotor cortex) were additionally associated with poor recovery of production errors in pantomime. Conceptual errors in pantomime after temporal and supramarginal gyrus lesions persisted into the chronic stage. However, they resolved completely when related to angular gyrus or insular lesions. CONCLUSION: The diverging courses of recovery in different apraxia tasks can be related to different mechanisms. Critical lesions to key structures of the network or entrance areas of the processing streams lead to persisting deficits in the corresponding tasks. Contrary, lesions located outside the core network but inducing a temporary network dysfunction allow good recovery e.g., of conceptual errors in pantomime. The identification of lesion correlates for different long-term recovery patterns in apraxia might also allow early clinical prediction of the course of recovery.

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Performance in verbal fluency tasks are widely used as a marker of cognitive impairment in Parkinson disease. However, the anatomical substrate of its impairment remains undetermined. Based on the dual-stream language model, we hypothesized cortical input to the subcortical circuitry would be a crucial determinant of fluency. We performed a retrospective study using individual whole-brain structural connectomes derived from 135 individuals with PD and assessed the relationship between white matter integrity and verbal fluency tasks. Controlling for multiple factors, including dysarthria, we observed higher integrity of dorsal stream-caudate connectivity was associated with better letter fluency. This preliminary study indicates the possible dissociation between dorsal and ventral stream connectivity and letter fluency in PD. In addition, it suggests a non-motor role of the frontostriatal fibers in letter fluency.

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Syntax, the structure of sentences, enables humans to express an infinite range of meanings through finite means. The neurobiology of syntax has been intensely studied but with little consensus. Two main candidate regions have been identified: the posterior inferior frontal gyrus (pIFG) and the posterior middle temporal gyrus (pMTG). Integrating research in linguistics, psycholinguistics, and neuroscience, we propose a neuroanatomical framework for syntax that attributes distinct syntactic computations to these regions in a unified model. The key theoretical advances are adopting a modern lexicalized view of syntax in which the lexicon and syntactic rules are intertwined, and recognizing a computational asymmetry in the role of syntax during comprehension and production. Our model postulates a hierarchical lexical-syntactic function to the pMTG, which interconnects previously identified speech perception and conceptual-semantic systems in the temporal and inferior parietal lobes, crucial for both sentence production and comprehension. These relational hierarchies are transformed via the pIFG into morpho-syntactic sequences, primarily tied to production. We show how this architecture provides a better account of the full range of data and is consistent with recent proposals regarding the organization of phonological processes in the brain.

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Objective:To study the effect of right brain language network in post-stroke aphasia (PSA) patients with left hemisphere injury. Methods:From December, 2018 to June, 2019, twelve PSA patients with left hemisphere injury, and twelve matched healthy controls were recruited to accept rest-state functional magnetic resonance imaging (f-MRI) scan, and analyzed the characteristics of right brain function network with Dual Stream model. Results:There were two patients lost. Compared with the controls, for dorsolateral lingual pathway, the functional connections increased from superior marginal gyrus to middle frontal gyrus and inferior frontal gyrus of trigone in the patients, while those decreased from posterior central gyrus to inferior frontal gyrus of insula. For ventral lingual pathway, the functional connection increased from angular gyrus to orbital inferior frontal gyrus. For ventral and dorsolateral double-pathway, the functional connections increased from temporal lobe to lenticular pallidum and angular gyrus, from caudate nucleus to inferior frontal gyrus of insula, from lenticular putamen nucleus to middle frontal gyrus and trigonometry, while it decreased from superior marginal gyrus and temporal lobe to inferior frontal gyrus of insula. There was a negative correlation between the functional connection from inferior frontal gyrus to lenticular putamen and repeating (r = -0.720, P < 0.05), between the functional connection from inferior frontal gyrus to the caudate nucleus to speaking and repeating (r < -0.696, P < 0.05). In terms of network index, there were significant differences between the patients and the controls in both local and global indexes for language key brain area in right brain (|t| > 2.143, P < 0.05). Conclusion:The functional network has reorganized in right hemisphere of PSA patients. However, the increase of connection between language critical cortex and subcortical nuclei may play a role in improvement of language function.

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The auditory dorsal stream has been implicated in sensorimotor integration and concatenation of sequential sound events, both being important for processing of speech and music. The auditory ventral stream, by contrast, is characterized as subserving sound identification and recognition. We studied the respective roles of the dorsal and ventral streams, including recruitment of basal ganglia and medial temporal lobe structures, in the processing of tone sequence elements. A sequence was presented incrementally across several runs during functional magnetic resonance imaging in humans, and we compared activation by sequence elements when heard for the first time ("novel") versus when the elements were repeating ("familiar"). Our results show a shift in tone-sequence-dependent activation from posterior-dorsal cortical areas and the basal ganglia during the processing of less familiar sequence elements towards anterior and ventral cortical areas and the medial temporal lobe after the encoding of highly familiar sequence elements into identifiable auditory objects.

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Auditory cognitive deficits after stroke may concern language and/or music processing, resulting in aphasia and/or amusia. The aim of the present study was to assess the potential deficits of auditory short-term memory for verbal and musical material after stroke and their underlying cerebral correlates with a Voxel-based Lesion Symptom Mapping approach (VLSM). Patients with an ischemic stroke in the right (N=10) or left (N=10) middle cerebral artery territory and matched control participants (N=14) were tested with a detailed neuropsychological assessment including global cognitive functions, music perception and language tasks. All participants then performed verbal and musical auditory short-term memory (STM) tasks that were implemented in the same way for both materials. Participants had to indicate whether series of four words or four tones presented in pairs, were the same or different. To detect domain-general STM deficits, they also had to perform a visual STM task. Behavioral results showed that patients had lower performance for the STM tasks in comparison with control participants, regardless of the material (words, tones, visual) and the lesion side. The individual patient data showed a double dissociation between some patients exhibiting verbal deficits without musical deficits or the reverse. Exploratory VLSM analyses suggested that dorsal pathways are involved in verbal (phonetic), musical (melodic), and visual STM, while the ventral auditory pathway is involved in musical STM.

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With the introduction of continuous flash suppression (CFS) as a method to render stimuli invisible and study unconscious visual processing, a novel hypothesis has gained popularity. It states that processes typically ascribed to the dorsal visual stream can escape CFS and remain functional, while ventral stream processes are suppressed when stimuli are invisible under CFS. This notion of a CFS-specific "dorsal processing bias" has been argued to be in line with core characteristics of the influential dual-stream hypothesis of visual processing which proposes a dissociation between dorsally mediated vision-for-action and ventrally mediated vision-for-perception. Here, we provide an overview of neuroimaging and behavioral studies that either examine this dorsal processing bias or base their conclusions on it. We show that both evidence for preserved ventral processing as well as lack of dorsal processing can be found in studies using CFS. To reconcile the diverging results, differences in the paradigms and their effects are worthy of future research. We conclude that given the current level of information a dorsal processing bias under CFS cannot be universally assumed.

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Recent behavioral and neuroimaging studies using continuous flash suppression (CFS) have suggested that action-related processing in the dorsal visual stream might be independent of perceptual awareness, in line with the "vision-for-perception" versus "vision-for-action" distinction of the influential dual-stream theory. It remains controversial if evidence suggesting exclusive dorsal stream processing of tool stimuli under CFS can be explained by their elongated shape alone or by action-relevant category representations in dorsal visual cortex. To approach this question, we investigated category- and shape-selective functional magnetic resonance imaging-blood-oxygen level-dependent responses in both visual streams using images of faces and tools. Multivariate pattern analysis showed enhanced decoding of elongated relative to non-elongated tools, both in the ventral and dorsal visual stream. The second aim of our study was to investigate whether the depth of interocular suppression might differentially affect processing in dorsal and ventral areas. However, parametric modulation of suppression depth by varying the CFS mask contrast did not yield any evidence for differential modulation of category-selective activity. Together, our data provide evidence for shape-selective processing under CFS in both dorsal and ventral stream areas and, therefore, do not support the notion that dorsal "vision-for-action" processing is exclusively preserved under interocular suppression.

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A central implication of the two-visual-systems hypothesis (TVSH) is that the dorsal visuomotor system (vision-for-action) can make use of invisible information, whereas the ventral system (vision-for-perception) cannot (Milner & Goodale, 1995). Therefore, actions such as grasping movements should be influenced by invisible information while conscious reports remain unaffected. To test this assumption, we used a dichoptic stimulation technique--continuous flash suppression (CFS)--which has the potency to render stimuli invisible for up to seconds (Tsuchiya & Koch, 2005). In two experiments using CFS, participants were asked to grasp for invisible bars of different sizes (Experiment 1) or orientations (Experiment 2), or to report both measures verbally. Target visibility was measured trial-by-trial using the perceptual awareness scale (PAS). We found no evidence for the use of invisible information by the visuomotor system despite extensive training (600 trials) and the availability of haptic feedback. Participants neither learned to scale their maximum grip aperture to the size of the invisible stimulus, nor to align their hand to its orientation. Careful control of stimulus visibility across training sessions, however, revealed a robust tendency towards decreasing perceptual thresholds under CFS. We discuss our results within the framework of the TVSH and with respect to alternative models which emphasize the close functional interaction between the dorsal and ventral visual systems.

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Primate studies have recently identified the dorsal stream as constituting multiple dissociable pathways associated with a range of specialized cognitive functions. To elucidate the nature and number of dorsal pathways in the human brain, the current study utilized in vivo probabilistic tractography to map the structural connectivity associated with subdivisions of the left supramarginal gyrus (SMG). The left SMG is a prominent region within the dorsal stream, which has recently been parcellated into five structurally-distinct regions which possess a dorsal-ventral (and rostral-caudal) organisation, postulated to reflect areas of functional specialisation. The connectivity patterns reveal a dissociation of the arcuate fasciculus into at least two segregated pathways connecting frontal-parietal-temporal regions. Specifically, the connectivity of the inferior SMG, implicated as an acoustic-motor speech interface, is carried by an inner/ventro-dorsal arc of fibres, whilst the pathways of the posterior superior SMG, implicated in object use and cognitive control, forms a parallel outer/dorso-dorsal crescent.

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Deficits in language and communication are among the core symptoms of autism, a common neurodevelopmental disorder with long-term impairment. Despite the striking nature of the autistic language impairment, knowledge about its corresponding alterations in the brain is still evolving. We hypothesized that the dual stream language network is altered in autism, and that this alteration could be revealed by changes in the relationships between microstructural integrity and functional activation. The study recruited 20 right-handed male youths with autism and 20 carefully matched individually, typically developing (TD) youths. Microstructural integrity of the left dorsal and left ventral pathways responsible for language processing and the functional activation of the connected brain regions were investigated by using diffusion spectrum imaging and functional magnetic resonance imaging of a semantic task, respectively. Youths with autism had significantly poorer language function, and lower functional activation in left dorsal and left ventral regions of the language network, compared with TD youths. The TD group showed a significant correlation of the functional activation of the left dorsal region with microstructural integrity of the left ventral pathway, whereas the autism group showed a significant correlation of the functional activation of the left ventral region with microstructural integrity of the left dorsal pathway, and moreover verbal comprehension index was correlated with microstructural integrity of the left ventral pathway. These altered structure-function relationships in autism suggest possible involvement of the dual pathways in supporting deficient semantic processing.

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Singing provides a unique opportunity to examine music performance-the musical instrument is contained wholly within the body, thus eliminating the need for creating artificial instruments or tasks in neuroimaging experiments. Here, more than two decades of voice and singing research will be reviewed to give an overview of the sensory-motor control of the singing voice, starting from the vocal tract and leading up to the brain regions involved in singing. Additionally, to demonstrate how sensory feedback is integrated with vocal motor control, recent functional magnetic resonance imaging (fMRI) research on somatosensory and auditory feedback processing during singing will be presented. The relationship between the brain and singing behavior will be explored also by examining: (1) neuroplasticity as a function of various lengths and types of training, (2) vocal amusia due to a compromised singing network, and (3) singing performance in individuals with congenital amusia. Finally, the auditory-motor control network for singing will be considered alongside dual-stream models of auditory processing in music and speech to refine both these theoretical models and the singing network itself.