The role of inferior frontal gyrus and inferior parietal lobule in semantic processing of Chinese characters

IntroductionFirst Rank Symptoms (FRS) - a group of intriguing experiences characterized by striking breach of ‘self versus non-self’ boundaries - have had a critical influence on the diagnosis of schizophrenia. Inferior Parietal Lobule is implicated in the pathogenesis of FRS in Schizophrenia. However, the role of Planum Parietale (PP) in the genesis of FRS is yet to be examined.Aims & objectivesThis first time study (to the best of our knowledge), aims to examine antipsychotic-naïve schizophrenia patients for the effect of FRS status on volume of PP.MethodIn this study we examined the volume of PP in antipsychotic-naïve schizophrenia patients (n = 32; M:F = 16:16) in comparison with age, sex, and handedness matched (as a group) healthy comparison subjects (n = 34; M:F = 16:18) using valid method with good inter-rater reliability.ResultsFemale Schizophrenia patients showed significant volume reduction in right PP in comparison with female healthy controls (F = 7.2; p = 0.01). However, male patients did not. There was a significant effect of schneiderian FRS in female patients in that those who had FRS had significantly smaller volume of right PP than healthy controls (F = 3.8; p = 0.03); where those female patients who were FRS negative did not differ. Left PP volume did not differ between patients and controls.ConclusionsCurrent study supports previous studies which have implicated the role of parietal lobe in pathogenesis of FRS. Specific role of PP in FRS generation and possible implication of sex differences needs further systematic studies.

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Barking up the right tree: Univariate and multivariate fMRI analyses of homonym comprehension

10.1101/857268 ◽

2019 ◽

Author(s):

Paul Hoffman ◽

Andres Tamm

Keyword(s):

Semantic Processing ◽

Control Function ◽

Semantic Representation ◽

Inferior Frontal Gyrus ◽

Temporal Cortex ◽

Unrelated Word ◽

Test Case ◽

Neuroimaging Data ◽

The Right

AbstractHomonyms are a critical test case for investigating how the brain resolves ambiguity in language and, more generally, how context influences semantic processing. Previous neuroimaging studies have associated processing of homonyms with greater engagement of regions involved in executive control of semantic processing. However, the precise role of these areas and the involvement of semantic representational regions in homonym comprehension remain elusive. We addressed this by combining univariate and multivariate fMRI analyses of homonym processing. We tested whether multi-voxel activation patterns could discriminate between presentations of the same homonym in different contexts (e.g., bark following tree vs. bark following dog). The ventral anterior temporal lobe, implicated in semantic representation but not previously in homonym comprehension, showed this meaning-specific coding, despite not showing increased mean activation for homonyms. Within inferior frontal gyrus (IFG), a key site for semantic control, there was a dissociation between pars orbitalis, which also showed meaning-specific coding, and pars triangularis, which discriminated more generally between semantically related and unrelated word pairs. IFG effects were goal-dependent, only occurring when the task required semantic decisions, in line with a top-down control function. Finally, posterior middle temporal cortex showed a hybrid pattern of responses, supporting the idea that it acts as an interface between semantic representations and the control system. The study provides new evidence for context-dependent coding in the semantic system and clarifies the role of control regions in processing ambiguity. It also highlights the importance of combining univariate and multivariate neuroimaging data to fully elucidate the role of a brain region in semantic cognition.

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Activation in the right inferior parietal lobule reflects the representation of musical structure beyond simple pitch discrimination

10.31234/osf.io/pezdm ◽

2020 ◽

Author(s):

Isabelle Royal ◽

Dominique T Vuvan ◽

Benjamin Rich Zendel ◽

Nicolas Robitaille ◽

Marc Schönwiesner ◽

...

Keyword(s):

Inferior Frontal Gyrus ◽

Superior Temporal Gyrus ◽

Pitch Discrimination ◽

Musical Structure ◽

Inferior Parietal Lobule ◽

Functional Magnetic Resonance ◽

Pitch Structure ◽

Parietal Lobule ◽

The Right ◽

Tonal Pitch

Pitch discrimination tasks typically engage the superior temporal gyrus and the right inferior frontal gyrus. It is currently unclear whether these regions are equally involved in the processing of incongruous notes in melodies, which requires the representation of musical structure (tonality) in addition to pitch discrimination. To this aim, 14 participants completed two tasks while undergoing functional magnetic resonance imaging, one in which they had to identify a pitch change in a series of non-melodic repeating tones and a second in which they had to identify an incongruous note in a tonal melody. In both tasks, the deviants activated the right superior temporal gyrus. A contrast between deviants in the melodic task and deviants in the non-melodic task (melodic > non-melodic) revealed additional activity in the right inferior parietal lobule. Activation in the inferior parietal lobule likely represents processes related to the maintenance of tonal pitch structure in working memory during pitch discrimination.

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Transient disruption of the inferior parietal lobule impairs the ability to attribute intention to action

10.1101/2020.04.18.047787 ◽

2020 ◽

Author(s):

Jean-François Patri ◽

Andrea Cavallo ◽

Kiri Pullar ◽

Marco Soriano ◽

Martina Valente ◽

...

Keyword(s):

Discrimination Task ◽

Action Observation ◽

Inferior Frontal Gyrus ◽

Inferior Parietal Lobule ◽

Reach To Grasp ◽

Movement Kinematics ◽

Measured Activity ◽

Parietal Lobule ◽

Computational Analyses ◽

Theta Burst

AbstractAlthough it is well established that fronto-parietal regions are active during action observation, whether they play a causal role in the ability to infer others’ intentions from visual kinematics remains undetermined. In experiments reported here, we combined offline continuous theta-burst stimulation (cTBS) with computational modeling to reveal single-trial computations in the inferior parietal lobule (IPL) and inferior frontal gyrus (IFG). Participants received cTBS over the left anterior IPL and the left IFG pars orbitalis, in separate sessions, before completing an intention discrimination task (discriminate intention of observed reach-to-grasp acts) or a kinematic discrimination task (discriminate peak wrist height of the same acts) unrelated to intention. We targeted intentions-sensitive regions whose fMRI-measured activity accurately discriminated intention from the same action stimuli. We found that transient disruption of activity of the left IPL, but not the IFG, impaired the observer’s ability to judge intention from movement kinematics. Kinematic discrimination unrelated to intention, in contrast, was largely unaffected. Computational analyses revealed that IPL cTBS did not impair the ability to ‘see’ changes in movement kinematics, nor did it alter the weight given to informative versus non-informative kinematic features. Rather, it selectively impaired the ability to link variations in informative features to the correct intention. These results provide the first causal evidence that left anterior IPL maps kinematics to intentions.

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Morphological and laminar distribution of cholescystokinine - immunoreactive neurons in cortex of human inferior parietal lobule and their clinical significance

Medicinski pregled ◽

10.2298/mpns0810452p ◽

2008 ◽

Vol 61 (9-10) ◽

pp. 452-457 ◽

Cited By ~ 1

Author(s):

Laslo Puskas ◽

Saveta Draganic-Gajic ◽

Slobodan Malobabic ◽

Nela Puskas ◽

Dragan Krivokuca ◽

...

Keyword(s):

Morphological Analysis ◽

Parietal Lobe ◽

Angular Gyrus ◽

Inferior Parietal Lobule ◽

Human Cortex ◽

Psychic Disorders ◽

Laminar Distribution ◽

Parietal Lobule ◽

Human Brains

Introduction. Cholecystocinine is a neuropeptide whose function in the cortex has not yet been clarified, although its relation with some psychic disorders has been noticed. Previous studies have not provided detailed data about types, or arrangement of neurons that contain those neuropeptide in the cortex of human inferior parietal lobe. The aim of this study was to examine precisely the morphology and typography of neurons containing cholecytocinine in the human cortex of inferior parietal lobule. Material and methods. There were five human brains on which we did the immunocystochemical research of the shape and laminar distribution of cholecystocinine immunoreactive neurons on serial sections of supramarginal gyrus and angular gyrus. The morphological analysis of cholecystocinine-immunoreactive neurons was done on frozen sections using avidin-biotin technique, by antibody to cholecystocinine diluted in the proportion 1:6000 using diamine-benzedine. Results. Cholecystocinine immunorective neurons were found in the first three layers of the cortex of inferior parietal lobule, and their densest concentration was in the 2nd and 3rd layer. The following types of neurons were found: bipolar neurons, then its fusiform subtype, Cajal-Retzius neurons (in the 1st layer), reverse pyramidal (triangular) and unipolar neurons. The diameters of some types of neurons were from 15 to 35 ?m, and the diameters of dendritic arborization were from 85-207 ?m. A special emphasis is put on the finding of Cajal-Retzius neurons that are immunoreactive to cholecystocinine, which demands further research. Conclusion. Bearing in mind numerous clinical studies pointing out the role of cholecystokinine in the pathogenesis of schizophrenia, the presence of a great number of cholecystokinine immunoreactive neurons in the cortex of inferior parietal lobule suggests their role in the pathogenesis of schizophrenia.

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