scholarly journals The Contribution of the Left Inferior Frontal Gyrus in Affective Processing of Social Groups

2018 ◽  
Author(s):  
Tiziano Suran ◽  
Raffaella I Rumiati ◽  
Luca Piretti
Keyword(s):  
Inferior Frontal Gyrus ◽  
Social Groups ◽  
Control Site ◽  
Affective Processing ◽  
Social Stimuli ◽  
Left Inferior Frontal Gyrus ◽  
Negative Valence ◽  
Semantic Priming Effect ◽  
Pars Opercularis ◽  
Stimulation Of

We investigated the contribution of the pars opercularis of the left inferior frontal gyrus (LIFGop) in representing knowledge about social groups. We asked healthy individuals to categorize words preceded by semantically congruent or incongruent primes while stimulating the LIFGop. Previous studies showing an involvement of the LIFGop both in processing social stimuli and negative valence words led us to predict that its stimulation would affect responses to negative social category words. Compared to the Vertex as control site, the stimulation of the LIFGop increased the speed of categorization of negative social groups, and disrupted the semantic priming effect for negative words overall. Within the framework of recent theories of semantic memory, we argue that the present results provide initial evidence of the representation of social groups being characterized by affective properties, whose processing is supported by the LIFGop.

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

2002 ◽  
Vol 14 (1) ◽  
pp. 11-23 ◽  
Author(s):  
Christian J. Fiebach ◽  
Angela D. Friederici ◽  
Karsten Müller ◽  
D. Yves von Cramon
Keyword(s):  
Word Processing ◽  
Inferior Frontal Gyrus ◽  
Low Frequency ◽  
Brain Regions ◽  
Visual Word ◽  
Middle Temporal Gyrus ◽  
Lexical Selection ◽  
Left Inferior Frontal Gyrus ◽  
Pars Opercularis ◽  
Left Middle Temporal Gyrus

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.

scholarly journals Dissociating semantic and phonological contributions of the left inferior frontal gyrus to language production

2019 ◽  
Author(s):  
Jana Klaus ◽  
Gesa Hartwigsen
Keyword(s):  
Phonological Processing ◽  
Language Production ◽  
Semantic Processing ◽  
Repetitive Transcranial Magnetic Stimulation ◽  
Inferior Frontal Gyrus ◽  
Control Site ◽  
Generation Task ◽  
Left Inferior Frontal Gyrus ◽  
Functional Relevance ◽  
Naming Latencies

While the involvement of the left inferior frontal gyrus (IFG) in language production is undisputed, the role of specific subregions at different representational levels remains unclear. Some studies suggest a division of anterior and posterior regions for semantic and phonological processing, respectively. Crucially, evidence thus far only comes from correlative neuroimaging studies, but the functional relevance of the involvement of these subregions during a given task remains elusive. We applied repetitive transcranial magnetic stimulation (rTMS) over anterior and posterior IFG (aIFG/pIFG), and vertex as a control site, while participants performed a category member and a rhyme generation task. We found a functional-anatomical double dissociation between tasks and subregions. Naming latencies were significantly delayed in the semantic task when rTMS was applied to aIFG (relative to pIFG and vertex). In contrast, we observed a facilitation of naming latencies in the phonological task when rTMS was applied to pIFG (relative to aIFG and vertex). The results provide first causal evidence for the notion that anterior portions of the IFG are selectively recruited for semantic processing while posterior regions are functionally specific for phonological processing during word production. These findings shed light on the functional parcellation of the left IFG in language production.

scholarly journals Functional Activation and Connectivity of the Left Inferior Frontal Gyrus during Lexical and Phonological Retrieval

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1655
Author(s):  
Miguel Ángel Rivas-Fernández ◽  
Benxamín Varela-López ◽  
Susana Cid-Fernández ◽  
Santiago Galdo-Álvarez
Keyword(s):  
Speech Production ◽  
Cognitive Processing ◽  
Inferior Frontal Gyrus ◽  
Naming Task ◽  
Phonological Information ◽  
Cortical Networks ◽  
Left Inferior Frontal Gyrus ◽  
Neural Information ◽  
Pars Opercularis ◽  
Phonological Retrieval

Being language a paradigm of structural and functional asymmetry in cognitive processing, the left Inferior Frontal Gyrus has been consistently related to speech production. In fact, it has been considered a key node in cortical networks responsible for different components of naming. However, isolating these components (e.g., lexical, syntactic, and phonological retrieval) in neuroimaging studies is difficult due to the use of different baselines and tasks. In the present study, functional activation and connectivity of the left inferior frontal gyrus was explored using functional magnetic resonance imaging. Participants performed a covert naming task (pressing a button based on a phonological characteristic). Two conditions were compared: drawings of objects and single letters (baseline condition). Differences in activation and functional connectivity were obtained for objects and letters in different areas of the left Inferior Frontal Gyrus. The pars triangularis was involved in the retrieval of lexical-phonological information, showing a pattern of connectivity with temporal areas in the search for the name of objects and with perisylvanian areas for letters. Selection of phonological information seems to involve the pars opercularis both to letters and objects but recruiting supramarginal and superior temporal areas to letters, probably related to orthographic-phonological conversion. The results support the notion of the left Inferior Frontal Gyrus as a buffer forwarding neural information across cortical networks responsible for different components of speech production.

scholarly journals Syntactic Complexity and Frequency in the Neurocognitive Language System

2017 ◽  
Vol 29 (9) ◽  
pp. 1605-1620 ◽  
Author(s):  
Yun-Hsuan Yang ◽  
William D. Marslen-Wilson ◽  
Mirjana Bozic
Keyword(s):  
Language Comprehension ◽  
Multivariate Analyses ◽  
Inferior Frontal Gyrus ◽  
Temporal Cortex ◽  
Frequency Effect ◽  
Syntactic Complexity ◽  
Left Inferior Frontal Gyrus ◽  
Fmri Study ◽  
Key Factor ◽  
Frequent Items

Prominent neurobiological models of language follow the widely accepted assumption that language comprehension requires two principal mechanisms: a lexicon storing the sound-to-meaning mapping of words, primarily involving bilateral temporal regions, and a combinatorial processor for syntactically structured items, such as phrases and sentences, localized in a left-lateralized network linking left inferior frontal gyrus (LIFG) and posterior temporal areas. However, recent research showing that the processing of simple phrasal sequences may engage only bilateral temporal areas, together with the claims of distributional approaches to grammar, raise the question of whether frequent phrases are stored alongside individual words in temporal areas. In this fMRI study, we varied the frequency of words and of short and long phrases in English. If frequent phrases are indeed stored, then only less frequent items should generate selective left frontotemporal activation, because memory traces for such items would be weaker or not available in temporal cortex. Complementary univariate and multivariate analyses revealed that, overall, simple words (verbs) and long phrases engaged LIFG and temporal areas, whereas short phrases engaged bilateral temporal areas, suggesting that syntactic complexity is a key factor for LIFG activation. Although we found a robust frequency effect for words in temporal areas, no frequency effects were found for the two phrasal conditions. These findings support the conclusion that long and short phrases are analyzed, respectively, in the left frontal network and in a bilateral temporal network but are not retrieved from memory in the same way as simple words during spoken language comprehension.

Syntactic Dependencies as Memorized Sequences in the Brain

2005 ◽  
Vol 50 (1-4) ◽  
pp. 241-266 ◽  
Author(s):  
Yosef Grodzinsky
Keyword(s):  
Working Memory ◽  
Inferior Frontal Gyrus ◽  
Functional Neuroanatomy ◽  
Left Inferior Frontal Gyrus ◽  
Broca’S Region ◽  
Syntactic Representation ◽  
Syntactic Approach ◽  
Syntactic Relations ◽  
Syntactic Dependencies ◽  
The Brain

AbstractThe prospects of a cognitive neuroscience of syntax are considered with respect to functional neuroanatomy of two seemingly independent systems: Working Memory and syntactic representation and processing. It is proposed that these two systems are more closely related than previously supposed. In particular, it is claimed that a sentence with anaphoric dependencies involves several Working Memories, each entrusted with a different linguistic function. Components of Working Memory reside in the Left Inferior Frontal Gyrus, which is associated with Broca’s region. When lesioned, this area manifests comprehension disruptions in the ability to analyze intra-sentential dependencies, suggesting that Working Memory spans over syntactic computations. The unification of considerations regarding Working Memory with a purely syntactic approach to Broca’s regions leads to the conclusion that mechanisms that compute transformations—and no other syntactic relations—reside in this area.

Foix-Chavany-Marie syndrome caused by a disconnection between the right pars opercularis of the inferior frontal gyrus and the supplementary motor area

2012 ◽  
Vol 117 (5) ◽  
pp. 844-850 ◽  
Author(s):  
Juan Martino ◽  
Enrique Marco de Lucas ◽  
Francisco Javier Ibáñez-Plágaro ◽  
José Manuel Valle-Folgueral ◽  
Alfonso Vázquez-Barquero
Keyword(s):  
Supplementary Motor Area ◽  
Diffusion Tensor ◽  
Anterior Part ◽  
Inferior Frontal Gyrus ◽  
Motor Area ◽  
Lower Limbs ◽  
Rare Type ◽  
Orofacial Movement ◽  
Pars Opercularis ◽  
The Right

Foix-Chavany-Marie syndrome (FCMS) is a rare type of suprabulbar palsy characterized by an automaticvoluntary dissociation of the orofacial musculature. Here, the authors report an original case of FCMS that occurred intraoperatively while resecting the pars opercularis of the inferior frontal gyrus. This 25-year-old right-handed man with an incidentally diagnosed right frontotemporoinsular tumor underwent surgery using an asleep-awake-asleep technique with direct cortical and subcortical electrical stimulation and a transopercular approach to the insula. While resecting the anterior part of the pars opercularis the patient suffered sudden anarthria and bilateral facial weakness. He was unable to speak or show his teeth on command, but he was able to voluntarily move his upper and lower limbs. This syndrome lasted for 8 days. Postoperative diffusion tensor imaging tractography revealed that connections of the pars opercularis of the right inferior frontal gyrus with the frontal aslant tract (FAT) and arcuate fasciculus (AF) were damaged. This case supplies evidence for localizing the structural substrate of FCMS. It was possible, for the first time in the literature, to accurately correlate the occurrence of FCMS to the resection of connections between the FAT and AF, and the right pars opercularis of the inferior frontal gyrus. The FAT has been recently described, but it may be an important connection to mediate supplementary motor area control of orofacial movement. The present case also contributes to our knowledge of complication avoidance in operculoinsular surgery. A transopercular approach to insuloopercular gliomas can generate FCMS, especially in cases of previous contralateral lesions. The prognosis is favorable, but the patient should be informed of this particular hazard, and the surgeon should anticipate the surgical strategy in case the syndrome occurs intraoperatively in an awake patient.

Sign in / Sign up

Export Citation Format

Share Document