fMRI Evidence for Dual Routes to the Mental Lexicon in Visual Word Recognition

Event-related fMRI was used to investigate lexical decisions to words of high and low frequency of occurrence and to pseudowords. The results obtained strongly support dual-route models of visual word processing. By contrasting words with pseudowords, bilateral occipito-temporal brain areas and posterior left middle temporal gyrus (MTG) were identified as contributing to the successful mapping of orthographic percepts onto visual word form representations. Low-frequency words and pseudowords elicited greater activations than high-frequency words in the superior pars opercularis [Brodmann's area (BA) 44] of the left inferior frontal gyrus (IFG), in the anterior insula, and in the thalamus and caudate nucleus. As processing of these stimuli during lexical search is known to rely on phonological information, it is concluded that these brain regions are involved in grapheme-to-phoneme conversion. Activation in the pars triangularis (BA 45) of the left IFG was observed only for low-frequency words. It is proposed that this region is involved in processes of lexical selection.

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Altered Spontaneous Neural Activity and Functional Connectivity in Parkinson’s Disease With Subthalamic Microlesion

Frontiers in Neuroscience ◽

10.3389/fnins.2021.699010 ◽

2021 ◽

Vol 15 ◽

Author(s):

Bei Luo ◽

Yue Lu ◽

Chang Qiu ◽

Wenwen Dong ◽

Chen Xue ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Functional Connectivity ◽

Brain Activity ◽

Inferior Frontal Gyrus ◽

Low Frequency ◽

Brain Regions ◽

Angular Gyrus ◽

Middle Temporal Gyrus ◽

Precentral Gyrus

BackgroundTransient improvement in motor symptoms are immediately observed in patients with Parkinson’s disease (PD) after an electrode has been implanted into the subthalamic nucleus (STN) for deep brain stimulation (DBS). This phenomenon is known as the microlesion effect (MLE). However, the underlying mechanisms of MLE is poorly understood.PurposeWe utilized resting state functional MRI (rs-fMRI) to evaluate changes in spontaneous brain activity and networks in PD patients during the microlesion period after DBS.MethodOverall, 37 PD patients and 13 gender- and age-matched healthy controls (HCs) were recruited for this study. Rs-MRI information was collected from PD patients three days before DBS and one day after DBS, whereas the HCs group was scanned once. We utilized the amplitude of low-frequency fluctuation (ALFF) method in order to analyze differences in spontaneous whole-brain activity among all subjects. Furthermore, functional connectivity (FC) was applied to investigate connections between other brain regions and brain areas with significantly different ALFF before and after surgery in PD patients.ResultRelative to the PD-Pre-DBS group, the PD-Post-DBS group had higher ALFF in the right putamen, right inferior frontal gyrus, right precentral gyrus and lower ALFF in right angular gyrus, right precuneus, right posterior cingulate gyrus (PCC), left insula, left middle temporal gyrus (MTG), bilateral middle frontal gyrus and bilateral superior frontal gyrus (dorsolateral). Functional connectivity analysis revealed that these brain regions with significantly different ALFF scores demonstrated abnormal FC, largely in the temporal, prefrontal cortices and default mode network (DMN).ConclusionThe subthalamic microlesion caused by DBS in PD was found to not only improve the activity of the basal ganglia-thalamocortical circuit, but also reduce the activity of the DMN and executive control network (ECN) related brain regions. Results from this study provide new insights into the mechanism of MLE.

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Indirect White Matter Pathways Are Associated With Treated Naming Improvement in Aphasia

Neurorehabilitation and Neural Repair ◽

10.1177/1545968321999052 ◽

2021 ◽

pp. 154596832199905

Author(s):

Janina Wilmskoetter ◽

Julius Fridriksson ◽

Alexandra Basilakos ◽

Lorelei Phillip Johnson ◽

Barbara Marebwa ◽

...

Keyword(s):

White Matter ◽

Treatment Outcomes ◽

Inferior Frontal Gyrus ◽

Brain Regions ◽

Angular Gyrus ◽

Middle Temporal Gyrus ◽

Middle Temporal ◽

Pars Opercularis ◽

Left Hemisphere Stroke ◽

Linear Regressions

Background White matter disconnection of language-specific brain regions associates with worse aphasia recovery. Despite a loss of direct connections, many stroke survivors may maintain indirect connections between brain regions. Objective To determine (1) whether preserved direct connections between language-specific brain regions relate to better poststroke naming treatment outcomes compared to no direct connections and (2) whether for individuals with a loss of direct connections, preserved indirect connections are associated with better treatment outcomes compared to individuals with no connections. Methods We computed structural whole-brain connectomes from 69 individuals with chronic left-hemisphere stroke and aphasia who completed a 3-week-long language treatment that was supplemented by either anodal transcranial direct current stimulation (A-tDCS) or sham stimulation (S-tDCS). We determined differences in naming improvement between individuals with direct, indirect, and no connections using 1-way analyses of covariance and multivariable linear regressions. Results Independently of tDCS modality, direct or indirect connections between the inferior frontal gyrus pars opercularis and angular gyrus were both associated with a greater increase in correct naming compared to no connections ( P = .027 and P = .039, respectively). Participants with direct connections between the inferior frontal gyrus pars opercularis and middle temporal gyrus who received S-tDCS and participants with indirect connections who received A-tDCS significantly improved in naming accuracy. Conclusions Poststroke preservation of indirect white matter connections is associated with better treated naming improvement in aphasia even when direct connections are damaged. This mechanistic information can be used to stratify and predict treated naming recovery in individuals with aphasia.

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Brain Activation of College Students in China With Premenstrual Syndrome Localized by BOLD-fMRI

10.21203/rs.3.rs-568217/v1 ◽

2021 ◽

Author(s):

Dongmei Gao ◽

Mingzhou Gao ◽

Li An ◽

Yanhong Yu ◽

Jieqiong Wang ◽

...

Keyword(s):

College Students ◽

Premenstrual Syndrome ◽

Brain Area ◽

Inferior Frontal Gyrus ◽

Brain Regions ◽

Anterior Lobe ◽

Middle Temporal Gyrus ◽

Cerebellar Tonsil ◽

Bold Fmri ◽

Significant Difference

Abstract Background: Most studies on the mechanism behind premenstrual syndrome (PMS) have focused on fluctuating hormones, but little evidence exists regarding functional abnormalities in the affected brain regions of college students. Thus, the aim of this study is to localize PMS's abnormal brain regions by BOLD-fMRI in college students.Methods: Thirteen PMS patients and fifteen healthy control (HC) subjects underwent a BOLD-fMRI scan during the luteal phase induced by depressive emotion pictures. The BOLD-fMRI data were processed by SPM 8 software and rest software based on MATLAB platform. Each cluster volume threshold (cluster) was greater than 389 continuous voxels, and the brain area with single voxel threshold P < 0.05 (after correction) was defined as the area with a significant difference. The emotion report form and the instruction implementation checklist were used to evaluate the emotion induced by picture.Results: Compared to the HC, right inferior occipital gyrus, right middle occipital gyrus, right lingual gyrus, right fusiform gyrus, right inferior temporal gyrus, cerebelum_crus1_R，cerebelum_6_R, culmen, the cerebellum anterior lobe, tuber, cerebellar tonsil of PMS patients were enhanced activation. Sub-lobar，sub-gyral，extra-nuclear，right orbit part of superior frontal gyrus, right middle temporal gyrus, right Orbit part of inferior frontal gyrus, limbic lobe, right insula, bilateral anterior and adjacent cingulate gyrus, bilateral caudate, caudate head, bilateral putamen, left globus pallidus were decreased activation.Conclusion: Our findings may improve our understanding of the neural mechanisms involved in PMS.

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Dissociable brain correlates for depression, anxiety, dissociation, and somatization in depersonalization-derealization disorder

CNS Spectrums ◽

10.1017/s1092852913000588 ◽

2013 ◽

Vol 21 (1) ◽

pp. 35-42 ◽

Cited By ~ 13

Author(s):

Erwin Lemche ◽

Simon A. Surguladze ◽

Michael J. Brammer ◽

Mary L. Phillips ◽

Mauricio Sierra ◽

...

Keyword(s):

Inferior Frontal Gyrus ◽

Superior Temporal Gyrus ◽

Brain Regions ◽

Self Report ◽

Parahippocampal Gyrus ◽

Left Inferior Frontal Gyrus ◽

Symptoms Of Depression ◽

Caudate Head ◽

Brain Correlates ◽

The Right

ObjectiveThe cerebral mechanisms of traits associated with depersonalization-derealization disorder (DPRD) remain poorly understood.MethodHappy and sad emotion expressions were presented to DPRD and non-referred control (NC) subjects in an implicit event-related functional magnetic resonance imaging (fMRI) design, and correlated with self report scales reflecting typical co-morbidities of DPRD: depression, dissociation, anxiety, somatization.ResultsSignificant differences between the slopes of the two groups were observed for somatization in the right temporal operculum (happy) and ventral striatum, bilaterally (sad). Discriminative regions for symptoms of depression were the right pulvinar (happy) and left amygdala (sad). For dissociation, discriminative regions were the left mesial inferior temporal gyrus (happy) and left supramarginal gyrus (sad). For state anxiety, discriminative regions were the left inferior frontal gyrus (happy) and parahippocampal gyrus (sad). For trait anxiety, discriminative regions were the right caudate head (happy) and left superior temporal gyrus (sad).DiscussionThe ascertained brain regions are in line with previous findings for the respective traits. The findings suggest separate brain systems for each trait.ConclusionOur results do not justify any bias for a certain nosological category in DPRD.

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Neural Correlates for the Suppression of Habitual Behavior: A Functional MRI Study

Journal of Cognitive Neuroscience ◽

10.1162/0898929041502643 ◽

2004 ◽

Vol 16 (6) ◽

pp. 944-954 ◽

Cited By ~ 30

Author(s):

Miwa Matsubara ◽

Shuhei Yamaguchi ◽

Jiang Xu ◽

Shotai Kobayashi

Keyword(s):

Left Hemisphere ◽

Anterior Part ◽

Inferior Frontal Gyrus ◽

Critical Role ◽

Brain Regions ◽

Error Rates ◽

Left Inferior Frontal Gyrus ◽

Scanning Procedure ◽

Manual Responses ◽

Habitual Behavior

It has been suggested that inhibitory executive control of behavior is directed by the frontal lobes. We used functional magnetic resonance imaging to explore the brain regions that are involved in the inhibition of habitual manual responses. Fifteen right-handed subjects performed the rock–scissors– paper game against computer-simulated pictures of hands during the scanning procedure. The subjects were required to win, lose, or draw against the presented picture in a separate block. We considered that the situation in which subjects intentionally lost the game required the suppression of habitual behavior, because it is natural behavior for people to attempt to win the game. Compared with the WIN and DRAW conditions, the left premotor and sensorimotor areas were activated for both hand sessions with a positive correlation with error rates. Importantly, the LOSE condition in the case of the right hand yielded brain activation exclusively in the anterior part of the left inferior frontal gyrus, the activity which showed a negative correlation with error rates. Overall brain activations were predominant in the left hemisphere, irrespective of the hand used for the response. The results suggest that the anterior part of the left inferior frontal gyrus plays a critical role in the inhibition of habitual manual behavior, and that the left hemisphere is dominant for the selection of well-learned manual behavior.

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Discrimination of Schizophrenia Auditory Hallucinators by Machine Learning of Resting-State Functional MRI

International Journal of Neural Systems ◽

10.1142/s0129065715500070 ◽

2015 ◽

Vol 25 (03) ◽

pp. 1550007 ◽

Cited By ~ 38

Author(s):

Darya Chyzhyk ◽

Manuel Graña ◽

Döst Öngür ◽

Ann K. Shinn

Keyword(s):

Machine Learning ◽

Resting State ◽

Right Hemisphere ◽

Inferior Frontal Gyrus ◽

Low Frequency ◽

Brain Regions ◽

Classification Performance ◽

Applied Machine Learning ◽

Heschl’S Gyrus ◽

Heschl's Gyrus

Auditory hallucinations (AH) are a symptom that is most often associated with schizophrenia, but patients with other neuropsychiatric conditions, and even a small percentage of healthy individuals, may also experience AH. Elucidating the neural mechanisms underlying AH in schizophrenia may offer insight into the pathophysiology associated with AH more broadly across multiple neuropsychiatric disease conditions. In this paper, we address the problem of classifying schizophrenia patients with and without a history of AH, and healthy control (HC) subjects. To this end, we performed feature extraction from resting state functional magnetic resonance imaging (rsfMRI) data and applied machine learning classifiers, testing two kinds of neuroimaging features: (a) functional connectivity (FC) measures computed by lattice auto-associative memories (LAAM), and (b) local activity (LA) measures, including regional homogeneity (ReHo) and fractional amplitude of low frequency fluctuations (fALFF). We show that it is possible to perform classification within each pair of subject groups with high accuracy. Discrimination between patients with and without lifetime AH was highest, while discrimination between schizophrenia patients and HC participants was worst, suggesting that classification according to the symptom dimension of AH may be more valid than discrimination on the basis of traditional diagnostic categories. FC measures seeded in right Heschl's gyrus (RHG) consistently showed stronger discriminative power than those seeded in left Heschl's gyrus (LHG), a finding that appears to support AH models focusing on right hemisphere abnormalities. The cortical brain localizations derived from the features with strong classification performance are consistent with proposed AH models, and include left inferior frontal gyrus (IFG), parahippocampal gyri, the cingulate cortex, as well as several temporal and prefrontal cortical brain regions. Overall, the observed findings suggest that computational intelligence approaches can provide robust tools for uncovering subtleties in complex neuroimaging data, and have the potential to advance the search for more neuroscience-based criteria for classifying mental illness in psychiatry research.

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Investigation of changes in the activity and function of dry eye-associated brain regions using the amplitude of low frequency fluctuations(ALFF)method

Bioscience Reports ◽

10.1042/bsr20210941 ◽

2022 ◽

Author(s):

Tie Sun ◽

Hui-Ye Shu ◽

Jie-Li Wu ◽

Ting Su ◽

Yu-Ji Liu ◽

...

Keyword(s):

Dry Eye ◽

Brain Activity ◽

Pearson Correlation ◽

Inferior Frontal Gyrus ◽

Low Frequency ◽

Brain Regions ◽

Middle Frontal Gyrus ◽

Brain Areas ◽

Spontaneous Brain Activity ◽

Frequency Fluctuations

Objective: The local characteristics of spontaneous brain activity in patients with dry eye (DE) and its relationship with clinical characteristics were evaluated using the amplitude of low-frequency fluctuations (ALFF) method. Methods: A total of 27 patients with DE (10 males and 17 females) and 28 healthy controls (HCs) (10 males and 18 females) were recruited, matched according to sex, age, weight, and height, classified into the DE and HC groups, and examined using functional magnetic resonance imaging scans. Spontaneous brain activity changes were recorded using ALFF technology. Data were recorded and plotted on the receiver operating characteristic curve, reflecting changes in activity in different brain areas. Finally, Pearson correlation analysis was used to calculate the potential relationship between spontaneous brain activity abnormalities in multiple brain regions and clinical features in patients with DE. GraphPad Prism 8 (GraphPad Software, Inc.) was used to analyze the linear correlation between the Hospital Anxiety and Depression Scale and ALFF value. Results: Compared with HCs, the ALFF values of patients with DE were decreased in the right middle frontal gyrus/right inferior orbitofrontal cortex, left triangle inferior frontal gyrus, left middle frontal gyrus, and right superior frontal gyrus. In contrast, the ALFF value of patients with DE was increased in the left calcarine. Conclusion: There are significant fluctuations in the ALFF value of specific brain regions in patients with DE versus HCs. This corroborates previous evidence showing that the symptoms of ocular surface damage in patients with DE are related to dysfunction in specific brain areas.

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The neural bases of program comprehension: a coordinate-based fMRI meta-analysis

10.1101/2021.04.15.439937 ◽

2021 ◽

Author(s):

Yoshiharu Ikutani ◽

Takeshi D. Itoh ◽

Takatomi Kubo

Keyword(s):

Brain Activity ◽

Meta Analysis ◽

Inferior Frontal Gyrus ◽

Posterior Part ◽

Program Comprehension ◽

Brain Regions ◽

Middle Temporal Gyrus ◽

Activation Patterns ◽

Neural Bases ◽

Kernel Density Analysis

AbstractThe understanding of brain activity during program comprehension have advanced thanks to noninvasive neuroimaging techniques, such as functional magnetic resonance imaging (fMRI). However, individual neuroimaging studies of program comprehension often provided inconsistent results and made it difficult to identify the neural bases. To identify the essential brain regions, this study performed a small meta-analysis on recent fMRI studies of program comprehension using multilevel kernel density analysis (MKDA). Our analysis identified a set of brain regions consistently activated in various program comprehension tasks. These regions consisted of three clusters, each of which centered at the left inferior frontal gyrus pars triangularis (IFG Tri), posterior part of middle temporal gyrus (pMTG), and right middle frontal gyrus (MFG). Additionally, subsequent analyses revealed relationships among the activation patterns in the previous studies and multiple cognitive functions. These findings suggest that program comprehension mainly recycles the language-related networks and partially employs other domain-general resources in the human brain.

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Predictive entrainment of natural speech through two fronto-motor top-down channels

10.1101/280032 ◽

2018 ◽

Cited By ~ 3

Author(s):

Hyojin Park ◽

Gregor Thut ◽

Joachim Gross

Keyword(s):

Inferior Frontal Gyrus ◽

Low Frequency ◽

Precentral Gyrus ◽

Top Down ◽

Low Frequencies ◽

Left Inferior Frontal Gyrus ◽

Delta Phase ◽

Beta Power ◽

Intelligible Speech ◽

Spatio Temporal

AbstractNatural communication between interlocutors is enabled by the ability to predict upcoming speech in a given context. Previously we showed that these predictions rely on a fronto-motor top-down control of low-frequency oscillations in auditory-temporal brain areas that track intelligible speech. However, a comprehensive spatio-temporal characterisation of this effect is still missing. Here, we applied transfer entropy to source-localised MEG data during continuous speech perception. First, at low frequencies (1-4 Hz, brain delta phase to speech delta phase), predictive effects start in left fronto-motor regions and progress to right temporal regions. Second, at higher frequencies (14-18 Hz, brain beta power to speech delta phase), predictive patterns show a transition from left inferior frontal gyrus via left precentral gyrus to left primary auditory areas. Our results suggest a progression of prediction processes from higher-order to early sensory areas in at least two different frequency channels.

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Parental education is associated with differential engagement of neural pathways during inhibitory control

Scientific Reports ◽

10.1038/s41598-021-04152-4 ◽

2022 ◽

Vol 12 (1) ◽

Author(s):

Christopher N. Cascio ◽

Nina Lauharatanahirun ◽

Gwendolyn M. Lawson ◽

Martha J. Farah ◽

Emily B. Falk

Keyword(s):

Socioeconomic Status ◽

Response Inhibition ◽

Parental Education ◽

Brain Activity ◽

Inferior Frontal Gyrus ◽

Brain Regions ◽

Middle Temporal Gyrus ◽

Neural Pathways ◽

Performance Differences ◽

Education Performance

AbstractResponse inhibition and socioeconomic status (SES) are critical predictors of many important outcomes, including educational attainment and health. The current study extends our understanding of SES and cognition by examining brain activity associated with response inhibition, during the key developmental period of adolescence. Adolescent males (N = 81), aged 16–17, completed a response inhibition task while undergoing fMRI brain imaging and reported on their parents’ education, one component of socioeconomic status. A region of interest analysis showed that parental education was associated with brain activation differences in the classic response inhibition network (right inferior frontal gyrus + subthalamic nucleus + globus pallidus) despite the absence of consistent parental education-performance effects. Further, although activity in our main regions of interest was not associated with performance differences, several regions that were associated with better inhibitory performance (ventromedial prefrontal cortex, middle frontal gyrus, middle temporal gyrus, amygdala/hippocampus) also differed in their levels of activation according to parental education. Taken together, these results suggest that individuals from households with higher versus lower parental education engage key brain regions involved in response inhibition to differing degrees, though these differences may not translate into performance differences.

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