Left Superior Temporal Gyrus Research Articles

Fronto-temporal transcranial direct current stimulation (tDCS) for auditory verbal hallucination in schizophrenia

Objective Up to 25% of patients with schizophrenia present with auditory verbal hallucinations (AVH) that are refractory to drug treatment. In such cases, evidence suggests that fronto-temporal transcranial direct current stimulation (tDCS) could alleviate AVH but these results were mixed and controversial. Here, we aimed to investigate the clinical effect of tDCS on AVH and its physical effects by measuring injected electric field distribution in the brain of patients. We hypothesized the superiority of active tDCS over sham to decrease AVH and that patients who will respond to tDCS would display greater electric field distribution in the brain areas involved in AVH than non-responders. Method Sixty patients with schizophrenia and daily refractory AVH were randomly allocated to receive either active (2 mA, 20 min) or sham tDCS applied twice daily (5 days). The anode was placed over the left dorsolateral prefrontal cortex and the cathode over the left temporo-parietal cortex. AVH severity was assessed with the Hallucination Change Scale (HCS). A modelling of the injected electrical field based on the MRI of each patient was compared between responders (HCS ≤ 5) and non-responders. Results Active tDCS can significantly decrease AVH [F(1,54) = 4.52; P = 0.03] as compared to sham. The effect was significant immediately after the tDCS, remain significant 1 month after the tDCS but did not reach significance 3 months later. At baseline, patients of the active group who will respond to tDCS displayed higher electric field strength in the left superior temporal gyrus (STG) than non-responders. Conclusion Fronto-temporal tDCS may alleviate treatment-resistant AVH. High distribution of the electric field within the left STG was observed in responders.

An audiovisual integration deficit underlies reading failure in nontransparent writing systems: An fMRI study of Chinese children with dyslexia

Establishing the associations between speech sounds and visual scripts is an essential step for reading acquisition. Audiovisual integration deficits have been proposed to be a cause of developmental dyslexia, and this has been evidenced by behavioral and neural findings from alphabetic languages with relatively transparent orthographies. Here, using functional magnetic resonance imaging (fMRI) in a lexical decision task, this study examined the neural correlates of audiovisual integration deficits in Chinese children with dyslexia and age-matched controls. The results indicated that the children with dyslexia showed a reduced audiovisual congruency effect in the left angular gyrus, left superior temporal gyrus and left middle and superior frontal gyrus. Moreover, dyslexics showed reduced functional connectivity for the congruency effect between the left angular gyrus and both the left lingual gyrus and left cerebellum. The regional activation and functional connectivity abnormalities might underlie the ill-developed correspondence between orthographic and phonological information in Chinese dyslexia. This study, for the first time, illustrates the neural mechanisms of the audiovisual integration deficit in dyslexia in a nontransparent logographic writing system, extending our understanding of the neural basis of dyslexia.

Impact of AVM location on language cortex right-hemisphere reorganization: A voxel-based lesion-symptom mapping study

ObjectivesCerebral arteriovenous malformations (AVMs) are congenital malformations, and right-sided dominance of the language cortex is not a rare phenomenon for patients with AVM involving language area. We tried to use voxel-based lesion-symptom mapping (VLSM) method to depict the location of AVM nidus and to demonstrate the relationship between AVM location and the pattern of language cortex reorganization. Patients and methodsThe authors retrospectively reviewed clinical and imaging data of 70 adult patients with unruptured cerebral AVMs who underwent blood oxygen level–dependent (BOLD) functional magnetic resonance imaging (fMRI) of language task. All patients were right handed, and all lesions were located in the left cerebral hemisphere. Lateralization indexes (LI) of the BOLD signals were calculated for Broca and Wernicke areas separately and were used to reflect the degree of right-sided dominance of the two language areas. VLSM method was applied to study the relationship between AVM location and LI of language task activations. ResultsStatistical analysis revealed that the change of LI of Broca area was significantly associated with lesions located in the inferior frontal gyrus, pre- and post-central gyrus, supramarginal gyrus and middle frontal gyrus. The change of LI of Wernicke area was significantly associated with lesions located in the left superior, middle, inferior and transverse temporal gyrus. ConclusionThese findings provide new evidence that the language cortex reorganization patterns in AVM patients have anatomic specificity.

Exposure to linguistic labels during childhood modulates the neural architecture of race categorical perception

Perceptually categorizing a face to its racial belonging may have important consequences on interacting with people. However, race categorical perception (CP) has been scarcely investigated nor its developmental pathway. In this study, we tested the neurolinguistics rewiring hypothesis, stating that language acquisition modulates the brain processing of social perceptual categories. Accordingly, we investigated the electrophysiological correlates of race CP in a group of adults and children between 3 and 5 years of age. For both groups we found a greater modulation of the N400 connected with the processing of between category boundaries (i.e., faces belonging to different race groups) than within-category boundaries (i.e., different faces belonging to the same race group). This effect was the same in both adults and children, as shown by the comparable between-group amplitude of the differential wave (DW) elicited by the between-category faces. Remarkably, this effect was positively correlated with racial-labels acquisition, but not with age, in children. Finally, brain source analysis revealed the activation of a more modularized cortical network in adults than in children, with unique activation of the left superior temporal gyrus (STG) and the inferior frontal gyrus (IFG), which are areas connected to language processing. These are the first results accounting for an effect of language in rewiring brain connectedness when processing racial categories.

Abnormal Auditory Mismatch Fields in Children and Adolescents With 16p11.2 Deletion and 16p11.2 Duplication

BackgroundIndividuals with either deletion or duplication of the BP4–BP5 segment of chromosome 16p11.2 have varied behavioral phenotypes that may include autistic features, mild to moderate intellectual disability, and/or language impairment. However, the neurophysiological correlates of auditory language discrimination processing in individuals with 16p11.2 deletion and 16p11.2 duplication have not been investigated. MethodsMagnetoencephalography was used to measure magnetic mismatch fields (MMFs) arising from the left and right superior temporal gyrus during an auditory oddball paradigm with vowel stimuli (/a/ and /u/) in children and adolescents with 16p11.2 deletion or 16p11.2 duplication and in typically developing peers. One hundred twenty-eight participants ranging from 7 to 17 years of age were included in the final analysis (typically developing: n = 61, 12.08 ± 2.50 years of age; 16p11.2 deletion: n = 45, 11.28 ± 2.51 years of age; and 16p11.2 duplication: n = 22, 10.73 ± 2.49 years of age). ResultsDelayed MMF latencies were found in both 16p11.2 deletion and 16p11.2 duplication groups compared with typically developing subjects. In addition, these delayed MMF latencies were associated with language and cognitive ability, with prolonged latency predicting greater impairment. ConclusionsOur findings suggest that auditory MMF response delays are associated with clinical severity of language and cognitive impairment in individuals with either 16p11.2 deletion or 16p11.2 duplication, indicating a correlate of their shared/overlapping behavioral phenotype (and not a correlate of gene dosage).

Tai Chi Chuan vs General Aerobic Exercise in Brain Plasticity: A Multimodal MRI Study

This study contrasted the impact of Tai Chi Chuan and general aerobic exercise on brain plasticity in terms of an increased grey matter volume and functional connectivity during structural magnetic resonance imaging (sMRI) and resting-state functional magnetic resonance imaging (rs-fMRI), explored the advantages of Tai Chi Chuan in improving brain structure and function. Thirty-six college students were grouped into Tai Chi Chuan (Bafa Wubu of Tai Chi), general aerobic exercise (brisk walking) and control groups. Individuals were assessed with a sMRI and rs-fMRI scan before and after an 8-week training period. The VBM toolbox was used to conduct grey matter volume analyses. The CONN toolbox was used to conduct several seed-to-voxel functional connectivity analyses. We can conclude that compared with general aerobic exercise, eight weeks of Tai Chi Chuan exercise has a stronger effect on brain plasticity, which is embodied in the increase of grey matter volume in left middle occipital gyrus, left superior temporal gyrus and right middle temporal gyrus and the enhancement of functional connectivity between the left middle frontal gyrus and left superior parietal lobule. These findings demonstrate the potential and advantages of Tai Chi Chuan exercises in eliciting brain plasticity.

Aging-related differences in the cortical network subserving intelligible speech

Language communication is crucial throughout the lifespan. The current study investigated how aging affects the brain network subserving intelligible speech. Using functional magnetic resonance imaging, we compared brain responses to intelligible and unintelligible speech between older and young adults. Univariate and multivariate analyses revealed reduced brain activation and lower regional pattern distinctions in response to intelligible versus unintelligible speech in the left anterior superior temporal gyrus (aSTG) and the left inferior frontal gyrus (IFG) in the older compared with young adults. Notably, the functional connectivity between the left IFG and the left angular gyrus (AG) was increased and a significantly enhanced bidirectional effective connectivity between the left aSTG and the left AG was observed in the older adults for processing speech intelligibility. Our study revealed aging-related differences in the cortical activity for intelligible speech and suggested that increased frontal-temporal-parietal functional integration may help facilitate spoken language processing in older adults.

Radiation-induced changes in small world network in patients with nasopharyngeal carcinoma: a three-dimensional structure MRI imaging study

Objective To investigate the radiotherapy (RT)-induced changes in the brain structural network in patients with nasopharyngeal carcinoma (NPC). Methods Three-dimensional structural magnetic resonance data (3D-T1W) was adopted to investigate the structural network in 103 patients with NPC before and after receiving RT. The structural networks were then reconstructed using 3D-T1W. The radiation-induced changes in topology properties of small world network were analyzed by using graph theoretical analysis. Results Patients showed small world properties before and after RT. Compared with the pre-RT group, the global and local efficiency were lower, the shortest path length was longer and the clustering coefficient was less in the post-RT group. In addition, the hub regions in the post-RT group were significantly different from those in the pre-RT group, mainly located in the left rolandic operculum, right inferior frontal gyrus, right parahippocampal gyrus, right lingual gyrus, bilateral supramarginal gyrus, left superior temporal gyrus and temporal pole of the right middle temporal gyrus. Conclusion It is speculated that RT leads to high efficiency of network topology and information transmission, which provides a novel perspective for exploring the RT-induced brain changes, diagnosis of RT-induced injury and evaluation of RT efficacy. Key words: Nasopharyngeal neoplasm/radiotherapy; Voxel-based morphometry; Gray matter; Small world property

Enhanced left inferior frontal to left superior temporal effective connectivity for complex sentence comprehension: fMRI evidence from Chinese relative clause processing

Previous studies investigating the processing of complex sentences have demonstrated the involvement of the left inferior frontal gyrus (LIFG) and left superior temporal gyrus (LSTG), which might subserve ordering and storage of linguistic components, respectively, for sentence comprehension. However, how these brain regions are interconnected, especially during the processing of Chinese sentences, need to be further explored. In this study, the neural network supporting the comprehension of Chinese relative clause was identified. Both the LIFG and LSTG exhibited higher activation in processing subject-extracted relative clauses (SRCs) than object-extracted relative clauses (ORCs). Moreover, a Granger causality analysis revealed that the effective connectivity from the LIFG to LSTG was significant only when participants read Chinese SRCs, which were argued to be more difficult than ORCs. Contrary to the observations of an SRC advantage in most other languages, the present results provide clear neuroimaging evidence for an ORC advantage in Chinese.

Spectral slowing is associated with working memory performance in children born very preterm

Children born very preterm (VPT) often demonstrate selective difficulties in working memory (WM), which may underlie academic difficulties observed in this population. Despite this, few studies have investigated the functional networks underlying WM in young children born VPT, a period when cognitive deficits become apparent. Using magnetoencephalography, we examined the networks underlying the maintenance of visual information in 6-year-old VPT (n = 15) and full-term (FT; n = 20) children. Although task performance was similar, VPT children engaged different oscillatory mechanisms during WM maintenance. Within the FT group, we observed higher mean whole-brain connectivity in the alpha-band during the retention (i.e. maintenance) interval associated with correct compared to incorrect responses. VPT children showed reduced whole-brain alpha synchrony, and a different network organization with fewer connections. In the theta-band, VPT children demonstrated a slight increase in whole-brain connectivity during WM maintenance, and engaged similar network hubs as FT children in the alpha-band, including the left dorsolateral prefrontal cortex and superior temporal gyrus. These findings suggest that VPT children rely on the theta-band to support similar task performance. Altered oscillatory mechanisms may reflect a less mature pattern of functional recruitment underlying WM in VPT children, which may affect the processing in complex ecological situations.

Accelerated Clustered Sparse Acquisition to Improve Functional MRI for Mapping Language Functions.

Functional magnetic resonance imaging (fMRI) is a useful method for noninvasive presurgical functional mapping. However, the scanner environment is inherently unsuitable for the examination of auditory and language functions, due to the loud acoustic noise produced by the scanner. Interleaved acquisition methods alleviate this problem by providing a silent period for stimulus presentation and/or response control (sparse sampling) but at the expense of a diminished amount of data collected. There are possible improvements to these sparse acquisition methods that increase the amount of data by acquiring several images per event (clustered sampling). We tested accelerated clustered fMRI acquisition in comparison with conventional sparse sampling in a pilot study. The clustered and sparse acquisition techniques (7.4 minutes scanning time per protocol) were directly compared in 15 healthy subjects (8 men; mean age: 24 ± 3 years) using both a motor (tongue movement) and a language (overt picture-naming) task. Functional imaging data were analyzed using Statistical Parametric Mapping software (SPM12 Wellcome Department of Imaging Neuroscience, London, UK). For both tasks, activation levels were compared and Euclidean distances (EDs) between cluster centers (i.e., local activation maxima and centers of gravity) were calculated. Overlaps and laterality indices were computed for the picture-naming task. In addition, the feasibility of the clustered acquisition protocol in a clinical setting was assessed in one pilot patient. For both tasks, activation levels were higher using the clustered acquisition protocol, reflected by bigger cluster sizes (p < 0.05). Mean ED between cluster centers ranged between 9.9 ± 5.4 mm (left superior temporal gyrus; centers of gravity) and 16.6 ± 13.2 mm (left inferior frontal gyrus; local activation maxima) for the picture-naming task. Overlaps between sparse and clustered acquisition reached 88% (Simpson overlap coefficient). A similar activation pattern for both acquisition methods was also confirmed in the clinical case. Despite some drawbacks inherent to the acquisition technique, the clustered sparse sampling protocol showed increased sensitivity for activation in language-related cortical regions with short scanning times. Such scanning techniques may be particularly advantageous for investigating patients with contraindications for long scans (e.g., reduced attention span).

Intra-Regional Glu-GABA vs Inter-Regional Glu-Glu Imbalance: A 1H-MRS Study of the Neurochemistry of Auditory Verbal Hallucinations in Schizophrenia.

Glutamate (Glu), gamma amino-butyric acid (GABA), and excitatory/inhibitory (E/I) imbalance have inconsistently been implicated in the etiology of schizophrenia. Elevated Glu levels in language regions have been suggested to mediate auditory verbal hallucinations (AVH), the same regions previously associated with neuronal hyperactivity during AVHs. It is, however, not known whether alterations in Glu levels are accompanied by corresponding GABA alterations, nor is it known if Glu levels are affected in brain regions with known neuronal hypo-activity. Using magnetic resonance spectroscopy (MRS), we measured Glx (Glu+glutamine) and GABA+ levels in the anterior cingulate cortex (ACC), left and right superior temporal gyrus (STG), and left inferior frontal gyrus (IFG), in a sample of 77 schizophrenia patients and 77 healthy controls. Two MRS-protocols were used. Results showed a marginally significant positive correlation in the left STG between Glx and AVHs, whereas a significant negative correlation was found in the ACC. In addition, high-hallucinating patients as a group showed decreased ACC and increased left STG Glx levels compared to low-hallucinating patients, with the healthy controls in between the 2 hallucinating groups. No significant differences were found for GABA+ levels. It is discussed that reduced ACC Glx levels reflect an inability of AVH patients to cognitively inhibit their “voices” through neuronal hypo-activity, which in turn originates from increased left STG Glu levels and neuronal hyperactivity. A revised E/I-imbalance model is proposed where Glu-Glu imbalance between brain regions is emphasized rather than Glu-GABA imbalance within regions, for the understanding of the underlying neurochemistry of AVHs.

Memory response and neuroimaging correlates of a novel cognitive rehabilitation program for memory problems in epilepsy: A pilot study.

Memory deficits are very common in epilepsy, but no standard of care exists to effectively manage them. We assessed effectiveness of cognitive rehabilitation (CR) on memory and neural plasticity in people with epilepsy (PWE) reporting memory impairments. Nine PWE completed 6 weekly sessions adapted from 2 generic CR programs enriched with information regarding epilepsy. Participants completed neuropsychological, mood, and quality of life (QOLIE-31) measures prior and after completion of CR; 5/9 participants also completed pre- and post-CR fMRI while performing a verbal paired associates learning task. FMRI data were analyzed using group spatial independent components analysis methods; paired t-tests compared spatial activations for pre-/post-CR. Improvements were seen in immediate recall in Rey Auditory Verbal Learning Task, QOLIE-31, and read word recognition in paired associates task (all p's≤0.05). FMRI changes comparing pre-to-post CR were noted through increased activation in the left inferior frontal gyrus (IFG) and anterior cingulate and decreased activation in the left superior temporal gyrus; also noted were decreased activations in the default mode network (DMN), right cingulate, right middle temporal gyrus, right supramarginal gyrus, and increased DMN activation in the left cuneus. This study demonstrates feasibility of conducting CR program in PWE with fMRI as a mechanistic biomarker. Improvements in cognition and cortical plasticity await confirmation in larger samples.

Alterations of Regional Homogeneity in Parkinson's Disease Patients With Freezing of Gait: A Resting-State fMRI Study.

ObjectiveThe purposes of this study are to investigate the regional homogeneity (ReHo) of spontaneous brain activities in Parkinson’s disease (PD) patients with freeze of gait (FOG) and to investigate the neural correlation of movement function through resting-state functional magnetic resonance imaging (RS-fMRI).MethodsA total of 35 normal controls (NC), 33 PD patients with FOG (FOG+), and 35 PD patients without FOG (FOG−) were enrolled. ReHo was applied to evaluate the regional synchronization of spontaneous brain activities. Analysis of covariance (ANCOVA) was performed on ReHo maps of the three groups, followed by post hoc two-sample t-tests between every two groups. Moreover, the ReHo signals of FOG+ and FOG− were extracted across the whole brain and correlated with movement scores (FOGQ, FOG questionnaire; GFQ, gait and falls questionnaire).ResultsSignificant ReHo differences were observed in the left cerebrum. Compared to NC subjects, the ReHo of PD subjects was increased in the left angular gyrus (AG) and decreased in the left rolandic operculum/postcentral gyrus (Rol/PostC), left inferior opercular-frontal cortex, left middle occipital gyrus, and supramarginal gyrus (SMG). Compared to that of FOG−, the ReHo of FOG+ was increased in the left caudate and decreased in the left Rol/PostC. Within the significant regions, the ReHo of FOG+ was negatively correlated with FOGQ in the left SMG/PostC (r = −0.39, p < 0.05). Negative correlations were also observed between ReHo and GFQ/FOGQ (r = −0.36/−0.38, p < 0.05) in the left superior temporal gyrus (STG) of the whole brain analysis based on AAL templates.ConclusionThe ReHo analysis suggested that the regional signal synchronization of brain activities in FOG+ subjects was most active in the left caudate and most hypoactive in the left Rol/PostC. It also indicated that ReHo in the left caudate and left Rol/PostC was critical for discriminating the three groups. The correlation between ReHo and movement scores (GFQ/FOGQ) in the STG has the potential to differentiate FOG+ from FOG−. This study provided new insight into the understanding of PD with and without FOG.

Aging and the wandering brain: Age-related differences in the neural correlates of stimulus-independent thoughts.

In recent years, several studies have indicated that healthy older adults exhibit a reduction in task-unrelated thoughts compared to young adults. However, much less is known regarding age-related differences in time spent engaging in stimulus-independent thoughts or in their neural correlates in the absence of an ongoing task. In the current study, we collected functional magnetic resonance imaging (fMRI) data while 29 young (mean age = 22y) and 22 older (mean age = 70y) adults underwent experience sampling in the absence of an ongoing task (i.e., at "rest"). Although both age groups reported spending a similar amount of time engaged in stimulus-independent thoughts, older adults rated their thoughts as more present-oriented (rather than atemporal) and more novel. Moreover, controlling for these age-related differences in content, we found that experiencing stimulus-independent thoughts was associated with increased posterior cingulate and left angular gyrus activation across age groups compared to exhibiting an external focus of attention. When experiencing stimulus-independent thoughts, younger adults engaged medial and left lateral prefrontal cortex as well as left superior temporal gyrus to a greater degree than older adults. Taken together, our results suggest that, in the absence of an ongoing task, although young and older adults spend a similar amount of time engaging in stimulus-independent thoughts, the content and neural correlates of these thoughts differ with age.

Electrophysiological evidence of phonemotopic representations of vowels in the primary and secondary auditory cortex

How the brain encodes the speech acoustic signal into phonological representations is a fundamental question for the neurobiology of language. Determining whether this process is characterized by tonotopic maps in primary or secondary auditory areas, with bilateral or leftward activity, remains a long-standing challenge. Magnetoencephalographic studies failed to show hierarchical and asymmetric hints for speech processing. We employed high-density electroencephalography to map the Salento Italian vowel system onto cortical sources using the N1 auditory evoked component. We found evidence that the N1 is characterized by hierarchical and asymmetrical indexes in primary and secondary auditory areas structuring vowel representations. Importantly, the N1 was characterized by early and late phases. The early N1 peaked at 125–135 msec and was localized in the primary auditory cortex; the late N1 peaked at 145–155 msec and was localized in the left superior temporal gyrus. We showed that early in the primary auditory cortex, the cortical spatial arrangements—along the lateral-medial and anterior-posterior gradients—are broadly warped by phonemotopic patterns according to the distinctive feature principle. These phonemotopic patterns are carefully refined in the superior temporal gyrus along the inferior-superior and anterior-posterior gradients. The dynamical and hierarchical interface between primary and secondary auditory areas and the interaction effects between Height and Place features generate the categorical representation of the Salento Italian vowels.

Neuron loss and dysfunctionality in hippocampus explain aircraft noise induced working memory impairment: a resting-state fMRI study on military pilots.

Long-term aircraft noise exposure may cast a detrimental effect upon the working memory of military pilots, and the brain structural and functional bases of noise related cognitive impairment remains unclear. In this study, we enrolled 30 fighter jet pilots and 30 matched controls. The working memory performance of the subjects was measured with a neurobehavioral test battery including immediate verbal/visual memory and delayed verbal/visual memory tests. Structural MRI and resting-state functional magnetic resonance imaging (rs-fMRI) were utilized to quantify brain grey matter volumes (GMV), regional homogeneity (ReHo), amplitude of low-frequency fluctuation (ALFF) and fractional ALFF (fALFF) differences between the two groups. Furthermore, correlation analyses were performed to find the association between the neural imaging changes with individual neurobehavioral performance. The military pilots showed significantly lower accuracy in delayed verbal and visual memory tests in comparison to the controls, indicating a potential working memory deficit in this population. Structural MRI data and rs-fMRI data showed that the pilots displayed markedly decreased GMVs, ReHo and ALFF signals in the left hippocampus, suggesting neuron dysfunction of the hippocampus. Besides, ReHo and ALFF/fALFF analysis also revealed reduced ReHo in the left amygdala, left thalamus, left superior temporal gyrus and right superior/middle frontal gyrus, indicating disrupted local neural activity under chronic noise exposure. Furthermore, Spearman correlation analysis proved that the GMV and ReHo of left hippocampus were significantly associated with working memory accuracy. This study provided direct evidence of dysfunctional hippocampus serving as the structural and functional bases for neuropsychological impairment under aircraft noise exposure.

A causal role of superior temporal gyrus in auditory-motor control of vocal production

Accumulating evidence has shown that the superior temporal gyrus (STG) plays an important role in auditory feedback control of vocal production. The precise role of this region in auditory-vocal integration, however, remains unclear. The present event-related potential study applied a transcranial magnetic stimulation (TMS) protocol, continuous theta-burst stimulation (c-TBS), to depress activity in the left STG as young adults produced sustained vowels while their voice was unexpectedly pitch-shifted downwards by 50 or 200 cents. The behavioral results showed significantly larger vocal compensations for pitch perturbations in the c-TBS condition as compared to the sham condition. At the cortical level, c-TBS over left STG led to significantly smaller cortical P2 responses than the sham condition. These findings provide the first causal evidence for linking the STG to auditory feedback control of vocal production. Enhanced vocal compensations for pitch perturbations as a result of disrupting the STG activity lend support to the idea that the STG may be critically involved in top-down inhibitory mechanisms of speech motor control, through which vocal motor behaviors can be appropriately regulated without being excessively influenced by auditory feedback.Accumulating evidence has shown that the superior temporal gyrus (STG) plays an important role in auditory feedback control of vocal production. The precise role of this region in auditory-vocal integration, however, remains unclear. The present event-related potential study applied a transcranial magnetic stimulation (TMS) protocol, continuous theta-burst stimulation (c-TBS), to depress activity in the left STG as young adults produced sustained vowels while their voice was unexpectedly pitch-shifted downwards by 50 or 200 cents. The behavioral results showed significantly larger vocal compensations for pitch perturbations in the c-TBS condition as compared to the sham condition. At the cortical level, c-TBS over left STG led to significantly smaller cortical P2 responses than the sham condition. These findings provide the first causal evidence for linking the STG to auditory feedback control of vocal production. Enhanced vocal compensations for pitch perturbations as a result of disrupting the STG activ...

Functional Connectivity of Language Regions of Stroke Patients with Expressive Aphasia During Real-Time Functional Magnetic Resonance Imaging Based Neurofeedback.

Stroke lesions in the language centers of the brain impair the language areas and their connectivity. This article describes the dynamics of functional connectivity (FC) of language areas (FCL) during real-time functional magnetic resonance imaging (RT-fMRI)-based neurofeedback training for poststroke patients with expressive aphasia. The hypothesis is that FCL increases during the upregulation of language areas during neurofeedback training and that the training improves FCL with an increasing number of sessions and restores it toward normalcy. Four test and four control patients with expressive aphasia were recruited for the study along with four healthy volunteers termed as the normal group. The test and normal groups were administered four neurofeedback training sessions in between two test sessions, whereas the control group underwent only the two test sessions. The training session requires the subject to exercise language activity covertly so that it upregulates the feedback signal obtained from the Broca's area (in left inferior frontal gyrus) and amplifies the feedback when it is correlated with the Wernicke's area (in left superior temporal gyrus) using RT-fMRI. FC was measured by Pearson's correlation coefficient. The results indicate that the FC of the test group was weaker in the left hemisphere than that of the normal group, and post-training the connections have strengthened (correlation coefficient increases) in the left hemisphere when compared with the control group. The connections of language areas strengthened in both hemispheres during neurofeedback-based upregulation, and multiple training sessions strengthened new pathways and restored left hemispheric connections toward normalcy.

Cross-Validation of Paranoid-Depressive Scale and Functional MRI: New Paradigm for Neuroscience Informed Clinical Psychopathology.

There is reported a study performed with a novel paradigm aiming at investigation of the translational validity of von Zerssen’s paranoid-depression scale and its fMRI correlates in terms of focus on exploration of the results on the contrast between the Paranoid Specific (DP) blocks and the Depression Specific (DS) blocks. Patients with schizophrenia demonstrated significant activations in a number of regions (right angular gyrus, left posterior cingulate and precuneus, right transverse temporal gyrus) during responses to paranoia versus depression items which differ topologically from those found in patients with major depression (left middle cingulate and right superior temporal gyrus). The direct comparison between the groups, however, did not yield any residual activations after correction.