The inferior frontal gyrus (IFG) is a part of the prefrontal cortex involved in language processing and speech production. It has three subdivisions: opercular, triangular, and orbital parts, which are associated with different functions such as phonology, semantics, and inhibition. The inferior frontal gyrus is limited above by the inferior frontal sulcus and below by the external border of the hemisphere in the front, and by the Sylvian fissure behind. It makes up the lateral and inferior surface of the frontal lobe and is separated from the middle frontal gyrus above by the inferior frontal sulcus.
The inferior frontal gyrus is responsible for language and contains the motor speech area. In the comparison of unconscious processing and baseline, clusters formed in the left superior parietal gyrus, right insular gyrus, and right inferior frontal gyrus form clusters. The inferior frontal gyrus is the lowest positioned gyrus of the frontal gyri, of the frontal lobe, and is part of the prefrontal cortex. It constitutes a large part of the ventrolateral surface of the prefrontal cortex and is delimited dorsally by the horizontally directed gyrus frontalis inferior.
The left inferior frontal gyrus (LIFG) is a key node of the neural networks engaged in language processing in the human brain and has been associated with various cognitive functions, including attention, motor inhibition, and imagery. The orbital part of the inferior frontal gyrus, also known as the pars orbitalis, is the orbital part of the inferior frontal gyrus.
In summary, the inferior frontal gyrus is a crucial part of the prefrontal cortex, responsible for language processing and speech production. It is divided into three sub-parts: opercular, triangular, and orbital, each with its own functions and functions.
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Superior frontal gyrus, middle frontal gyrus, inferior frontal gyrus. Superior temporal gyrus, middle temporal gyrus, inferior temporal …
What is the inferior frontal gyrus in MRI?
The inferior frontal gyrus is a part of the frontal lobe, forming the lateral and inferior surface. It is separated from the middle frontal gyrus by the inferior frontal sulcus and contains the frontal operculum, which hides the anterosuperior part of the insular cortex. The inferior edge of the gyrus abuts the lateral sulcus, which divides it into three parts: the anterior ramus, which separates the pars orbitalis from the pars triangularis, and the ascending ramus, which separates the pars triangularis from the pars opercularis. The operculum is responsible for hiding the anterosuperior part of the insular cortex.
Is Broca’s area the inferior frontal gyrus?
The Broca area is a region of the left hemisphere of the human brain that is responsible for speech production. It is situated within the inferior frontal gyrus. The website employs the use of cookies, and by continuing to utilize the website, you are indicating your consent to their usage. Copyright © 2024 Elsevier B. V., its licensors, and contributors. All rights are reserved, including those pertaining to text and data mining, AI training, and analogous technologies.
What is the difference between the superior frontal gyrus and the inferior frontal gyrus?
The superior frontal gyrus is a region of the brain that is situated in the medial aspect of the frontal lobe, adjacent to the cingulate gyrus and the corpus callosum. The superior frontal gyrus is subdivided into three portions: opercular, triangular, and orbital. All rights are reserved for text and data mining, artificial intelligence training, and similar technologies.
What gyri is on the inferior surface?
The fusiform gyrus, which extends from the temporal lobe to the occipital lobe, is divided into anterior and posterior fusiform gyri. The fusiform gyrus is circumscribed by the temporal pole on the anterior surface and by the collateral sulcus on the medial surface. The lateral border is represented by the occipito-temporal sulcus, while the posterior border is the occipital pole.
What is the inferior surface of the frontal lobe?
The inferior surface of the frontal lobe is the smallest cortical surface of the lobe, located anterior to the Sylvian fissure stem and on the floor of the anterior cranial fossa. It is divided into two parts by two sulci, with the olfactory sulcus running anteroposteriorly. The orbital gyri are divided by the H-shaped orbital sulcus into four gyri, two above and below the transverse part of the “H” and two on either side.
What is the inferior parietal gyrus?
The inferior parietal lobule is responsible for perception of emotions, sensory information interpretation, language, mathematical operations, and body image, particularly the supramarginal gyrus and angular gyrus. Damage to the dominant hemisphere results in Gerstmann’s syndrome, while damage to the non-dominant hemisphere results in topographic memory loss, anosognosia, construction apraxia, dressing apraxia, contralateral hemispatial neglect, contralateral hemianopia, or lower quadrantanopia.
Functional imaging experiments suggest that the left anterior supramarginal gyrus (aSMG) of the human inferior parietal lobule exhibits an evolved specialization related to tool use. However, the uniqueness of the human aSMG is an open question due to its habitual use of tools by chimpanzees.
What is another name for the inferior frontal gyrus?
The inferior frontal gyrus, consisting of the opercular, triangular, and orbital parts, plays a crucial role in speech and language processing. The opercular part, known as Brodmann area 44 (BA44), is part of the articulatory network, which includes the premotor cortex and anterior insula. These areas have specific functions in speech comprehension and production, primarily controlling the motor aspect of speech production. The pars opercularis indirectly controls the motor aspect of speech production, coding motor programs, while the auditory cortex houses sensory targets.
Together, these areas function as a sensory-motor loop for syllable information coding. Neural circuitry connects different sites of stimulus to other response regions, including other subdivisions and other frontal gyri. The articulatory network acts mostly when the vocal tract moves to produce syllables.
What is another name for the inferior temporal gyrus?
The inferior temporal gyrus, also known as the Inferior Temporal Gyrus, is an anterior region of the temporal lobe located beneath the central temporal sulcus. Its primary function is visual stimuli processing, specifically object recognition, and has been suggested as the final location of the ventral cortical visual system. The IT cortex in humans processes visual stimuli in our field of vision, memory, and recall to identify objects. It is involved with the processing and perception created by visual stimuli amplified in the V1, V2, V3, and V4 regions of the occipital lobe.
The IT cortex’s neurological significance extends beyond its role in object recognition. It is also vital for simple processing of the visual field, difficulties with perceptual tasks and spatial awareness, and the location of unique single cells that may explain its relation to memory.
The temporal lobe is unique to primates, and in humans, the IT cortex is more complex than their relative primate counterparts. The human inferior temporal cortex consists of the inferior temporal gyrus, the middle temporal gyrus, and the fusiform gyrus. The inferior temporal gyrus is located along the bottom portion of the temporal lobe and is separated from the middle temporal gyrus by the inferior temporal sulcus. Non-human primates have an inferior temporal cortex that is not divided into unique regions like humans’ inferior temporal gyrus, fusiform gyrus, or middle temporal gyrus.
What is an inferior surface?
The diaphragmatic surface, formed by the ventricles, is oriented in a downward and slightly posterior direction and is in contact with the central tendon and a minor portion of the left muscular portion of the diaphragm.
What happens if the inferior frontal gyrus is damaged?
The right inferior frontal gyrus (rIFG) is a crucial control function in the human brain, with studies showing that lesions to this region increase stop-signal reaction time (SSRT), a latent variable that expresses the speed of inhibitory control. However, recent work has identified limitations of the SSRT method, including trigger failures, which are stop-signal trials in which inhibitory control was never initiated. These trials inflate SSRT but are typically indicative of attentional deficits.
This study used hierarchical Bayesian modeling to identify stop-signal trigger failures in human rIFG lesion patients, non-rIFG lesion patients, and healthy comparisons. Additionally, scalp-EEG was measured to detect β-bursts, a neurophysiological index of inhibitory control. rIFG lesion patients showed a more than fivefold increase in trigger failure trials and did not exhibit the typical increase of stop-related frontal β-bursts.
However, on trials where such β-bursts did occur, rIFG patients showed the typical subsequent upregulation of β over sensorimotor areas, indicating that their ability to implement inhibitory control, once triggered, remains intact.
Humans have remarkable cognitive control abilities, such as the ability to stop an already-initiated action when crossing a street. Inhibitory control is typically tested in the stop-signal task, where an initial go-signal is sometimes followed by a subsequent stop-signal, prompting the cancellation of that movement. The horse-race model, which describes the processes underlying behavior in the stop-signal task, allows for the calculation of stop-signal reaction time (SSRT).
A seminal study on the neural basis of inhibitory control, Aron et al., 2003, showed that lesions to the right inferior frontal gyrus (rIFG) are associated with an elongation of SSRT, prompting the proposal that “response inhibition can be localized to a discrete region of the PFC, namely, the rIFG”.
Why is the inferior frontal gyrus important?
The left inferior frontal gyrus (LIFG) is a crucial part of cognitive functions such as language, executive function, and social cognition. However, the functional organization of the LIFG remains unclear. The study aimed to explore its topographical organization using a bimodal data-driven approach. Functional connectivity gradients were extracted from resting-state fMRI time-series of 150 participants and patterns of co-activation derived meta-analytically from task data across various cognitive domains. The researchers used seed-based resting-state FC and meta-analytic co-activation modelling analyses to characterize the differences driving these gradients.
The results showed a graded functional organization of the LIFG, shifted along two main organizational axes. An anterior-posterior gradient was more tightly coupled with perceptually-driven networks, while a second dorsal-ventral axis was characterized by higher connectivity with domain-general control networks and the semantic network. This suggests that the LIFG is an interface between distinct large-scale functional networks, underpinning both task-free and task-constrained mental states.
The extent of overlap in the LIFG’s role in cognitive domains is remarkable, but the driving mechanism remains unknown. One possibility is that the LIFG subserves a singular function, manifesting as common activation across domains, or that detailed exploration of its organization could reveal subregions with multiple functional specialisations.
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… Superior Frontal Gyris (Gyrius Frontalis Superior) – Middle Forntal Gyris (Gyris Forntalis MEdius) – Inferior Frontal Gyrus (Gyrus …
Here’s an explanation of why it is called “pars opercularis”: \t1.\tAnatomical Location: The frontal lobe is one of the major divisions of the cerebral cortex and is responsible for various cognitive functions, including motor control, executive functions, and language processing. Within the frontal lobe, there are several distinct regions or gyri, which are raised folds of the cortex. \t2.\tOperculum: The term “opercularis” is derived from the Latin word “operculum,” which means “lid” or “cover.” In the context of the brain, an “operculum” refers to a covering or lid-like structure that partially conceals another structure. \t3.\tAppearance: The pars opercularis is named so because it covers or partially conceals a crucial part of the brain called the “insular cortex.” The insular cortex is located deep within the lateral sulcus (also known as the lateral fissure) and is not immediately visible on the surface of the brain. The pars opercularis forms a sort of “lid” or covering over the insular cortex. 😊
I really like this article, because it gives me an overview of the gyri of the brain that I have yet to master as a resident. I was wondering if you also noticed a disparity in the nomenclature of what you mentioned as the lateral occipital gyrus, with most text books referring to it as the “middle occipital gyrus”. This can be observed with a quick google search for both terms. Thank you!
Hey Dr’s/students: Just read a report from ‘81 when my husband was 7 & evaluated for hearing & learning difficulties. He does have some genetic hearing loss. Heschy’ls gyru mentioned in report. Something about it being blocked or maybe nvr formed? He doesn’t have issues w/ memory. I saw schizotypal mentioned on google w/ this Heschyl’s mentioned. His mother is severely schizophrenic. Any info you can add on connection?