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Handbook of Clinical Neurology 2018There are few reports of patients with parietal lobe epilepsy. One of the largest series, from the Montreal Neurological Institute (MNI), reported that patients with... (Review)
Review
There are few reports of patients with parietal lobe epilepsy. One of the largest series, from the Montreal Neurological Institute (MNI), reported that patients with epileptogenic areas in the parietal cortex behind the postcentral gyrus comprised 6% of patients with refractory focal epilepsy treated surgically at the MNI between 1929 and 1988. Since then several other institutions have reported their experience with the evaluation and treatment of patients with parietal lobe epilepsy. This chapter reviews the functional anatomy of the parietal lobe, electroclinical manifestations and surgical outcome of parietal lobe epilepsy, and recent advances in the evaluation of patients with refractory focal epilepsy.
Topics: Epilepsies, Partial; Humans; Parietal Lobe
PubMed: 29519472
DOI: 10.1016/B978-0-444-63622-5.00021-8 -
Handbook of Clinical Neurology 2018Although the parietal lobe was considered by many of the earliest investigators of disordered language to be a major component of the neural systems instantiating... (Review)
Review
Although the parietal lobe was considered by many of the earliest investigators of disordered language to be a major component of the neural systems instantiating language, most views of the anatomic substrate of language emphasize the role of temporal and frontal lobes in language processing. We review evidence from lesion studies as well as functional neuroimaging, demonstrating that the left parietal lobe is also crucial for several aspects of language. First, we argue that the parietal lobe plays a major role in semantic processing, particularly for "thematic" relationships in which information from multiple sensory and motor domains is integrated. Additionally, we review a number of accounts that emphasize the role of the left parietal lobe in phonologic processing. Although the accounts differ somewhat with respect to the nature of the linguistic computations subserved by the parietal lobe, they share the view that the parietal lobe is essential for the processes by which sound-based representations are transcoded into a format that can drive action systems. We suggest that investigations of the linguistic capacities of the parietal lobe constrained by the understanding of the parietal lobe in action and multimodal sensory integration may serve to enhance not only our understanding of language, but also the relationship between language and more basic brain functions.
Topics: Humans; Language; Parietal Lobe
PubMed: 29519469
DOI: 10.1016/B978-0-444-63622-5.00018-8 -
Journal of Clinical Neurophysiology :... Oct 2012Patients with parietal lobe epilepsy (PLE) exhibit an electroclinical epilepsy syndrome that is rarely seen even at large epilepsy centers. Clinically, most patients... (Review)
Review
Patients with parietal lobe epilepsy (PLE) exhibit an electroclinical epilepsy syndrome that is rarely seen even at large epilepsy centers. Clinically, most patients with PLE exhibit a somatosensory aura that may include painful dysesthesias, though vertigo, aphasia, disturbances of one's body image also occur, when ictal propagation occurs from the parietal lobe to the supplementary motor area, hypermotor manifestations are noted. When temporolimbic propagation occurs, complex visual or auditory hallucinations and automatisms may appear. Scalp electroencephalogram (EEG) is often nonlocalizing. Ictal EEG is rarely localizing in PLE, and invasive EEG is often required for definitive localization and functional mapping. Recent advances in clinical neurophysiology during the evaluation of patients with refractory partial epilepsy include Ictal magnetic source imaging (MSI). Combined EEG and functional magnetic resonance imaging (EEG-fMRI) may be useful for patients with PLE to refine the localization in patients undergoing a presurgical evaluation. High-frequency oscillations (HFOs) are more concentrated inside the seizure onset zone (SOZ), indicating that they may be used as interictal scalp EEG biomarker for the SOZ. When medical therapy fails, resective epilepsy surgery can result in seizure freedom or significant reduction especially when a lesion is present.
Topics: Anticonvulsants; Brain Mapping; Brain Waves; Electroencephalography; Epilepsy; Humans; Magnetic Resonance Imaging; Neurosurgical Procedures; Parietal Lobe; Periodicity; Treatment Outcome
PubMed: 23027096
DOI: 10.1097/WNP.0b013e31826c9ebc -
Handbook of Clinical Neurology 2018The ability to craft and use tools is a crucial skill of human beings, distinguishing humans from all other species. Humans show a unique capacity to create novel,... (Review)
Review
The ability to craft and use tools is a crucial skill of human beings, distinguishing humans from all other species. Humans show a unique capacity to create novel, technologically advanced devices and represent physical causality using tools. In the present chapter we review the effect of tool use in changing body-space multisensory integration and body representation and the fundamental contribution of the parietal lobe to the neural underpinnings of tool use. In the final section we briefly introduce the effect of parietal brain damage on tool use. At the beginning of 20th century, a crucial role for the left parietal lobe for a proper control of gestures, including the pantomimed and actual use of tools, was already clear. Actual available evidence supports a critical role of the parietal lobe for both the lower-level multisensory integration of somatosensory and visual input necessary for the interactions between body, tools, and external objects, and for the representation of the mechanical and conceptual dynamics of tool use. Parietal regions, rather than merely representing the prototypical use of a tool, would be critical to understand the general mechanical interactions of the tool with the environment. The increase of knowledge about such brain mechanisms is of utmost relevance in the present times, characterized by the development of more and more sophisticated technological tools, such as functional prostheses, robotic interfaces, and virtual-reality devices.
Topics: Humans; Parietal Lobe; Tool Use Behavior
PubMed: 29519476
DOI: 10.1016/B978-0-444-63622-5.00025-5 -
Brain Structure & Function Jan 2023Traditional and new disciplines converge in suggesting that the parietal lobe underwent a considerable expansion during human evolution. Through the study of endocasts... (Review)
Review
Traditional and new disciplines converge in suggesting that the parietal lobe underwent a considerable expansion during human evolution. Through the study of endocasts and shape analysis, paleoneurology has shown an increased globularity of the braincase and bulging of the parietal region in modern humans, as compared to other human species, including Neandertals. Cortical complexity increased in both the superior and inferior parietal lobules. Emerging fields bridging archaeology and neuroscience supply further evidence of the involvement of the parietal cortex in human-specific behaviors related to visuospatial capacity, technological integration, self-awareness, numerosity, mathematical reasoning and language. Here, we complement these inferences on the parietal lobe evolution, with results from more classical neuroscience disciplines, such as behavioral neurophysiology, functional neuroimaging, and brain lesions; and apply these to define the neural substrates and the role of the parietal lobes in the emergence of functions at the core of material culture, such as tool-making, tool use and constructional abilities.
Topics: Humans; Anthropology, Cultural; Biological Evolution; Parietal Lobe; Skull
PubMed: 35451642
DOI: 10.1007/s00429-022-02487-w -
Advances in Neurology 2000When symptoms such as lateralized paresthesias or pain occur prominently and early in partial seizures, parietal lobe seizure origin should be suspected. Most patients... (Review)
Review
When symptoms such as lateralized paresthesias or pain occur prominently and early in partial seizures, parietal lobe seizure origin should be suspected. Most patients with parietal lobe seizures, however, have no symptoms or signs suggesting the parietal lobe. In the absence of detectable epileptogenic lesions, these patients without clinical seizure characteristics suggesting parietal lobe origin can present with misleading findings, resulting in erroneous localization, which can, in turn, lead to ineffective surgical intervention (23,25). Although ictal SPECT might provide vital evidence of parietal lobe seizure origin (25), as noted previously, this technology also can produce misleading data in some patients (52). Even when parietal lobe seizure origin is suspected, in the absence of a structural lesion, documenting this with invasive monitoring can be difficult. The parietal lobes, like the frontal lobes, are large, diffuse structures, and the potential for sampling error is high (19). Spread patterns are unpredictable and can result in false localization (23). Even with extensive and repetitive invasive studies, localization can prove elusive (53). No well-documented series of patients with non-lesional parietal lobe epilepsy in the modern literature who have been cured by surgery have been reported as a result of a combination of the rarity of the condition, the lack of correct recognition, as well as the difficulty of localization. Patients with medically intractable parietal lobe seizures, however, can experience excellent surgical results (23,24). Postoperative parietal lobe symptoms and signs, even when extreme, are usually not enduring (patient 3). One of our patients, however, did develop a chronic pain syndrome (48).
Topics: Epilepsy; Humans; Parietal Lobe
PubMed: 11091867
DOI: No ID Found -
Handbook of Clinical Neurology 2018The vestibular cortex differs in various ways from other sensory cortices. It consists of a network of several distinct and separate temporoparietal areas. Its core... (Review)
Review
The vestibular cortex differs in various ways from other sensory cortices. It consists of a network of several distinct and separate temporoparietal areas. Its core region, the parietoinsular vestibular cortex (PIVC), is located in the posterior insula and retroinsular region and includes the parietal operculum. The entire network is multisensory (in particular, vestibular, visual, and somatosensory). The peripheral and central vestibular systems are bilaterally organized; there are various pontomesencephalic brainstem crossings and at least two transcallosal connections of both hemispheres, between the PIVC and the motion-sensitive visual cortex areas, which also mediate vestibular input. Structural and functional vestibular dominance characterizes the right hemisphere in right-handers and the left hemisphere in left-handers. This explains why right-hemispheric lesions in right-handers more often generally cause hemispatial neglect and the pusher syndrome, both of which involve vestibular function. Vestibular input also contributes to cognition and may determine individual lateralization of brain functions such as handedness. Bilateral organization is a major key to understanding cortical functions and disorders, for example, the visual-vestibular interaction that occurs in spatial orientation. Although the vestibular cortex is represented in both hemispheres, there is only one global percept of body position and motion. The chiefly vestibular aspects of the multiple functions and disorders of the parietal lobe dealt with in this chapter cannot be strictly separated from various multisensory vestibular functions within the entire brain.
Topics: Animals; Cerebral Cortex; Functional Laterality; Humans; Parietal Lobe
PubMed: 29519455
DOI: 10.1016/B978-0-444-63622-5.00006-1 -
Handbook of Clinical Neurology 2018This chapter summarizes current knowledge on the structural segregation of the parietal lobe based on cyto-, myelo-, and receptorarchitectonic studies, as well as the... (Review)
Review
This chapter summarizes current knowledge on the structural segregation of the parietal lobe based on cyto-, myelo-, and receptorarchitectonic studies, as well as the connectivity of this brain region with other cortical and subcortical structures. The anterior part of the human parietal cortex comprises the somatosensory areas 3a, 3b, 1, and 2, whereas the posterior part contains seven multimodal areas in both the superior and inferior parietal lobules. Available cytoarchitectonic maps of the human intraparietal sulcus do not provide a complete picture yet. Myelo- and receptorarchitectonic analyses largely confirm but also further differentiate the cytoarchitectonic maps. With the advent of diffusion imaging and functional connectivity studies, further insight into the structural and functional organization has been achieved. It shows that the posterior parietal cortex is a key node in anatomic networks connecting visual with (pre)frontal cortices, and temporal with parts of frontal cortices. Here, the superior longitudinal fascicle and its components play a major role, together with the arcuate and middle longitudinal fascicles. Major connections with subcortical structures, particularly the basal ganglia and thalamic nuclei, are discussed. Finally, the importance of precise maps of parietal areas for defining seed regions in structural and functional connectivity studies is emphasized.
Topics: Animals; Brain Mapping; Humans; Nerve Net; Neural Pathways; Parietal Lobe
PubMed: 29519479
DOI: 10.1016/B978-0-444-63622-5.00003-6 -
Handbook of Clinical Neurology 2018The mirror mechanism is a basic mechanism that transforms sensory representations of others' actions into motor representations of the same actions in the brain of the... (Review)
Review
The mirror mechanism is a basic mechanism that transforms sensory representations of others' actions into motor representations of the same actions in the brain of the observer. The mirror mechanism plays an important role in understanding actions of others. In the present chapter we discuss first the basic organization of the posterior parietal lobe in the monkey, stressing that it is best characterized as a motor scaffold, on the top of which sensory information is organized. We then describe the location of the mirror mechanism in the posterior parietal cortex of the monkey, and its functional role in areas PFG, and anterior, ventral, and lateral intraparietal areas. We will then present evidence that a similar functional organization is present in humans. We will conclude by discussing the role of the mirror mechanism in the recognition of action performed with tools.
Topics: Animals; Humans; Mental Processes; Parietal Lobe
PubMed: 29519480
DOI: 10.1016/B978-0-444-63622-5.00028-0 -
Trends in Cognitive Sciences Sep 2005Although the parietal lobe is not traditionally thought to support declarative memory, recent event-related fMRI studies of episodic retrieval have consistently revealed... (Review)
Review
Although the parietal lobe is not traditionally thought to support declarative memory, recent event-related fMRI studies of episodic retrieval have consistently revealed a range of memory-related influences on activation in lateral posterior parietal cortex (PPC) and precuneus extending into posterior cingulate and retrosplenial cortex. This article surveys the fMRI literature on PPC activation during remembering, a literature that complements earlier electroencephalography data. We consider these recent memory-related fMRI responses within the context of classical ideas about parietal function that emphasize space-based attention and motor intention. We conclude by proposing three hypotheses concerning how parietal cortex might contribute to memory.
Topics: Brain Mapping; Electroencephalography; Functional Laterality; Humans; Magnetic Resonance Imaging; Mental Recall; Parietal Lobe; Recognition, Psychology
PubMed: 16054861
DOI: 10.1016/j.tics.2005.07.001