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Integrative Synchronization Mechanisms and Models in the Cognitive Neurosciences
Published in Harald Maurer, Cognitive Science, 2021
Recently, the canonical, neuronal, (synchronization) mechanisms of the complex cognitive function of language processing have been increasingly investigated by the German neuropsychologist, Angela D. Friederici and Wolf Singer323: "At the neuronal level, complex cognitive processes appear to be implemented by the integration of a large number of local processes into multidimensional coherent global states or, in other words, by the hierarchical nesting of operations realized at different scales in densely interconnected subnetworks of variable size. These principles appear to hold for all cognitive subsystems (...). Highly stereotyped, automatic processes such as syntactic computation are achieved in devoted subnetworks, as shown by the findings of strictly local processing of the most basic syntactic computations," i.e. the basic operation of "Merge"324 in the dorsal pathway connecting the left Brodmann area (BA) 44 (the pars opercularis Brocas area) and the posterior superior temporal gyrus (pSTG) that constitute the sentence-processing system. This is the neural substrate for the processing of syntactically complex sentences.
Preparing the Patient for the fMRI Study and Optimization of Paradigm Selection and Delivery
Published in Andrei I. Holodny, Functional Neuroimaging, 2019
The frontal speech areas mostly comprise the inferior frontal gyrus (pars triangularis and pars opercularis) of the left hemisphere (Fig. 1A). Broadly, the frontal speech area is involved in speech production. Lesions to this area produce a halting, expressive, or nonfluent aphasia (also termed “Broca’s aphasia”). Most commonly, patients with expressive aphasias perform well on measures of speech comprehension but display agrammatic or telegraphic speech (simplified, staccato-like sentences).
Functional Specialization of the Brain (General Theoretical Framework)
Published in Ivanka V. Asenova, Brain Lateralization and Developmental Disorders, 2018
In healthy subjects, a number of structural asymmetries in terms of cortical matter volume, surface area size, cortical thickness or white matter properties have been found (for a review, see [194]). It has been established that in most people the planum temporale in the LH (that roughly corresponds to Wernicke’s area) is typically larger compared to the RH [65, 75, 85, 111, 112, 121, 162, 191]. Similar left-right anatomical asymmetries have been found for Heschl’s gyrus [65, 85, 111, 121], planum parietale [162], Broca’s area [65, 112], pars triangulais [75], pars opercularis (but not in pars triangulais) [4] and hippocampal formation [85].
Reemergence of the language network during recovery from severe traumatic brain injury: A pilot functional MRI study
Published in Brain Injury, 2021
Brian J. Coffey, Zachary D. Threlkeld, Andrea S. Foulkes, Yelena G. Bodien, Brian L. Edlow
Current theories of speech processing involve dual cortical streams: a ventral stream (including STG and IFG) that is preferentially involved in decoding the meaning of spoken language and a dorsal stream (including pars opercularis, premotor areas, and posterior regions in the supramarginal gyrus) underlying articulation of spoken output. Based on this conceptualization, our fMRI paradigm, which involves passive listening to JFK’s inaugural address, should primarily target the ventral stream. However, our findings in healthy subjects and patients with severe TBI suggest additional language processing by the dorsal stream, which may be implicated in articulation of speech (42,43). Dorsal stream processing may also suggest familiarity with the presented speech stimulus, although our subjects were likely only familiar with the famous “ask not what your country can do for you – ask what you can do for your country” quote rather than the entire inaugural address. Alternatively, studies supporting the dual stream model of language processing may not generalize to our sample because they: 1) rely largely on data from non-human primates, healthy humans, or patients with stroke (11), 2) utilize non-standardized fMRI paradigms, or 3) apply structural lesion mapping to infer function (10). Finally, if TBI disrupts the dual stream processing of language, it is possible that longitudinal reorganization of the language network reduces the functional dissociation between the ventral and dorsal streams.
A review of magnetoencephalography use in pediatric epilepsy: an update on best practice
Published in Expert Review of Neurotherapeutics, 2021
Hiroshi Otsubo, Hiroshi Ogawa, Elizabeth Pang, Simeon M Wong, George M Ibrahim, Elysa Widjaja
Language is a complex function that requires the integration of distributed brain regions. However, damage to the traditional language hubs in Wernicke’s and Broca’s areas will result in deficits in receptive and productive language functions, respectively. For this reason, it is still important to lateralize or localize these two critical hubs. Receptive language areas, involved in the comprehension of spoken or written words, are located in the dominant hemisphere, at the posterior part of the superior temporal gyrus, extending to include the supramarginal and angular gyri (Brodmann Areas 22/30/40). In MEG, receptive language areas are activated by listening to single words or reading a written word. Expressive language areas, involved in the production of spoken or written language, are located on the dominant inferior frontal gyrus and encompassing pars opercularis and pars triangularis (Brodmann area 44/45).
Effectiveness of action observation therapy on upper extremity function in children with cerebral palsy: systematic review and meta-analysis
Published in Physical Therapy Reviews, 2021
Mai Elsayed Abbass, Nahla M. Ibrahim
The neural circuits underlying imitation learning were first discovered in the premotor cortex of monkeys. These neural circuits form a mirror neuron system activated during the action and when the animal observes the same action performed by another animal [24]. A series of studies showed that the mirror neuron system also exists in humans and is highly developed [25–31]. The mirror neuron system in humans is involved in understanding the actions of others and the intentions behind them. It is the underlying mechanism of observational learning [32]. The brain areas involved in action observation in humans are the inferior frontal gyrus, the rostral part of the inferior parietal lobule, the lower part of the precentral gyrus, and the temporal, parietal, occipital visual areas [33]. The frontal and parietal mirror neuron regions are organized somatotopically. Activation of the premotor cortex reflects proximal arm and neck movements. Activation of the pars opercularis of the inferior frontal gyrus reflects the observation of distal hand and mouth actions [33]. Mirror neurons in the parietal and frontal lobes are anatomically connected and integrated to form the frontoparietal motor neuron system with physiological properties relevant to sensorimotor integration [34]. Children with cerebral palsy may have perceptual disorders that might result in problems in the sensorimotor integration affecting motor learning [34].