251
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Ralph MAL, Jefferies E, Patterson K, Rogers TT. The neural and computational bases of semantic cognition. Nat Rev Neurosci 2016; 18:42-55. [PMID: 27881854 DOI: 10.1038/nrn.2016.150] [Citation(s) in RCA: 867] [Impact Index Per Article: 108.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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252
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Sarubbo S, De Benedictis A, Merler S, Mandonnet E, Barbareschi M, Dallabona M, Chioffi F, Duffau H. Structural and functional integration between dorsal and ventral language streams as revealed by blunt dissection and direct electrical stimulation. Hum Brain Mapp 2016; 37:3858-3872. [PMID: 27258125 PMCID: PMC6867442 DOI: 10.1002/hbm.23281] [Citation(s) in RCA: 54] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2016] [Revised: 05/07/2016] [Accepted: 05/24/2016] [Indexed: 01/24/2023] Open
Abstract
The most accepted framework of language processing includes a dorsal phonological and a ventral semantic pathway, connecting a wide network of distributed cortical hubs. However, the cortico-subcortical connectivity and the reciprocal anatomical relationships of this dual-stream system are not completely clarified. We performed an original blunt microdissection of 10 hemispheres with the exposition of locoregional short fibers and six long-range fascicles involved in language elaboration. Special attention was addressed to the analysis of termination sites and anatomical relationships between long- and short-range fascicles. We correlated these anatomical findings with a topographical analysis of 93 functional responses located at the terminal sites of the language bundles, collected by direct electrical stimulation in 108 right-handers. The locations of phonological and semantic paraphasias, verbal apraxia, speech arrest, pure anomia, and alexia were statistically analyzed, and the respective barycenters were computed in the MNI space. We found that terminations of main language bundles and functional responses have a wider distribution in respect to the classical definition of language territories. Our analysis showed that dorsal and ventral streams have a similar anatomical layer organization. These pathways are parallel and relatively segregated over their subcortical course while their terminal fibers are strictly overlapped at the cortical level. Finally, the anatomical features of the U-fibers suggested a role of locoregional integration between the phonological, semantic, and executive subnetworks of language, in particular within the inferoventral frontal lobe and the temporoparietal junction, which revealed to be the main criss-cross regions between the dorsal and ventral pathways. Hum Brain Mapp 37:3858-3872, 2016. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
- Silvio Sarubbo
- Division of Neurosurgery, Department of Neurosciences, "S. Chiara" Hospital, Trento APSS - 9 Largo Medaglie D'Oro, Trento, 38122, Italy.
- Structural and Functional Connectivity Lab, Division of Neurosurgery, "S. Chiara" Hospital, Trento APSS - 9 Largo Medaglie D'Oro, Trento, 38122, Italy.
| | - Alessandro De Benedictis
- Department of Neuroscience and Neurorehabilitation, Neurosurgery Unit, Bambino Gesù Children's Hospital - IRCCS, 4 Piazza Sant'Onofrio, Roma, 00165, Italy
| | - Stefano Merler
- Bruno Kessler Foundation (FBK), 18 via Sommarive, Trento, 38123, Italy
| | - Emmanuel Mandonnet
- Department of Neurosurgery, Lariboisiere Hospital, 2 Rue Ambroise Pare, Paris, 75010, France
| | - Mattia Barbareschi
- Department of Histopathology, "S. Chiara" Hospital, Trento APSS - 9 Largo Medaglie D'Oro, Trento, 38122, Italy
| | - Monica Dallabona
- Division of Neurosurgery, Department of Neurosciences, "S. Chiara" Hospital, Trento APSS - 9 Largo Medaglie D'Oro, Trento, 38122, Italy
| | - Franco Chioffi
- Division of Neurosurgery, Department of Neurosciences, "S. Chiara" Hospital, Trento APSS - 9 Largo Medaglie D'Oro, Trento, 38122, Italy
- Structural and Functional Connectivity Lab, Division of Neurosurgery, "S. Chiara" Hospital, Trento APSS - 9 Largo Medaglie D'Oro, Trento, 38122, Italy
| | - Hugues Duffau
- Department of Neurosurgery, Hôpital Gui De Chauliac, Montpellier University Medical Center, 80 Av Augustin Fliche, Montpellier, 34295, France
- Institute for Neuroscience of Montpellier, INSERM U1051, Team "Plasticity of Central Nervous System, Stem Cells and Glial Tumors," Saint Eloi Hospital, Montpellier, France
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253
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Spatial and non-spatial aspects of visual attention: Interactive cognitive mechanisms and neural underpinnings. Neuropsychologia 2016; 92:9-19. [DOI: 10.1016/j.neuropsychologia.2016.05.021] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 04/07/2016] [Accepted: 05/19/2016] [Indexed: 11/16/2022]
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254
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Toward a functional neuroanatomy of semantic aphasia: A history and ten new cases. Cortex 2016; 97:164-182. [PMID: 28277283 DOI: 10.1016/j.cortex.2016.09.012] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2015] [Revised: 04/17/2016] [Accepted: 09/18/2016] [Indexed: 11/21/2022]
Abstract
Almost 70 years ago, Alexander Luria incorporated semantic aphasia among his aphasia classifications by demonstrating that deficits in linking the logical relationships of words in a sentence could co-occur with non-linguistic disorders of calculation, spatial gnosis and praxis deficits. In line with his comprehensive approach to the assessment of language and other cognitive functions, he argued that deficits in understanding semantically reversible sentences and prepositional phrases, for example, were in line with a single neuropsychological factor of impaired spatial analysis and synthesis, since understanding such grammatical relationships would also draw on their spatial relationships. Critically, Luria demonstrated the neural underpinnings of this syndrome with the critical implication of the cortex of the left temporal-parietal-occipital (TPO) junction. In this study, we report neuropsychological and lesion profiles of 10 new cases of semantic aphasia. Modern neuroimaging techniques provide support for the relevance of the left TPO area for semantic aphasia, but also extend Luria's neuroanatomical model by taking into account white matter pathways. Our findings suggest that tracts with parietal connectivity - the arcuate fasciculus (long and posterior segments), the inferior fronto-occipital fasciculus, the inferior longitudinal fasciculus, the superior longitudinal fasciculus II and III, and the corpus callosum - are implicated in the linguistic and non-linguistic deficits of patients with semantic aphasia.
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255
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McCarthy RA, Warrington EK. Past, present, and prospects: Reflections 40 years on from the selective impairment of semantic memory (Warrington, 1975). Q J Exp Psychol (Hove) 2016; 69:1941-68. [DOI: 10.1080/17470218.2014.980280] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We summarize the main findings and conclusions of Warrington's (1975) paper, The Selective Impairment of Semantic memory, a neuropsychological paper that described three cases with degenerative neurological conditions [Warrington, E. K. (1975). The selective impairment of semantic memory. The Quarterly Journal of Experimental Psychology, 27, 635–657]. We consider the developments that have followed from its publication and give a selective overview of the field in 2014. The initial impact of the paper was on neuropsychological investigations of semantic loss followed some 14 years later by the identification of Semantic Dementia (the condition shown by the original cases) as a distinctive form of degenerative disease with unique clinical and pathological characteristics. We discuss the distinction between disorders of semantic storage and refractory semantic access, the evidence for category- and modality-specific impairments of semantics, and the light that has been shed on the structure and organization of semantic memory. Finally we consider the relationship between semantic memory and the skills of reading and writing, phonological processing, and autobiographical memory.
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Affiliation(s)
- Rosaleen A. McCarthy
- Department of Neuropsychology, Wessex Neurosciences Centre, Southampton University Hospital NHS Trust, Southampton, UK
- Department of Psychology, University of Southampton, Southampton, UK
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256
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Binney RJ, Hoffman P, Lambon Ralph MA. Mapping the Multiple Graded Contributions of the Anterior Temporal Lobe Representational Hub to Abstract and Social Concepts: Evidence from Distortion-corrected fMRI. Cereb Cortex 2016; 26:4227-4241. [PMID: 27600844 PMCID: PMC5066834 DOI: 10.1093/cercor/bhw260] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 07/03/2016] [Accepted: 07/30/2016] [Indexed: 11/13/2022] Open
Abstract
A growing body of recent convergent evidence indicates that the anterior temporal lobe (ATL) has connectivity-derived graded differences in semantic function: the ventrolateral region appears to be the transmodal, omni-category center-point of the hub whilst secondary contributions come from the peripheries of the hub in a manner that reflects their differential connectivity to different input/output modalities. One of the key challenges for this neurocognitive theory is how different types of concept, especially those with less reliance upon external sensory experience (such as abstract and social concepts), are coded across the graded ATL hub. We were able to answer this key question by using distortion-corrected fMRI to detect functional activations across the entire ATL region and thus to map the neural basis of social and psycholinguistically-matched abstract concepts. Both types of concept engaged a core left-hemisphere semantic network, including the ventrolateral ATL, prefrontal regions and posterior MTG. Additionally, we replicated previous findings of weaker differential activation of the superior and polar ATL for the processing of social stimuli, in addition to the stronger, omni-category activation observed in the vATL. These results are compatible with the view of the ATL as a graded transmodal substrate for the representation of coherent concepts.
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Affiliation(s)
- Richard J. Binney
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, ManchesterM13 9PL, UK
- Eleanor M. Saffran Center for Cognitive Neuroscience, Department of Communication Sciences and Disorders, Temple University, Philadelphia, PA19122, USA
| | - Paul Hoffman
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, ManchesterM13 9PL, UK
- Center for Cognitive Ageing and Cognitive Epidemiology, Department of Psychology, University of Edinburgh, EH8 9JZ, UK
| | - Matthew A. Lambon Ralph
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, ManchesterM13 9PL, UK
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257
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Miozzo M, Williams AC, McKhann GM, Hamberger MJ. Topographical gradients of semantics and phonology revealed by temporal lobe stimulation. Hum Brain Mapp 2016; 38:688-703. [PMID: 27654942 DOI: 10.1002/hbm.23409] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2015] [Revised: 09/12/2016] [Accepted: 09/13/2016] [Indexed: 01/18/2023] Open
Abstract
Word retrieval is a fundamental component of oral communication, and it is well established that this function is supported by left temporal cortex. Nevertheless, the specific temporal areas mediating word retrieval and the particular linguistic processes these regions support have not been well delineated. Toward this end, we analyzed over 1000 naming errors induced by left temporal cortical stimulation in epilepsy surgery patients. Errors were primarily semantic (lemon → "pear"), phonological (horn → "corn"), non-responses, and delayed responses (correct responses after a delay), and each error type appeared predominantly in a specific region: semantic errors in mid-middle temporal gyrus (TG), phonological errors and delayed responses in middle and posterior superior TG, and non-responses in anterior inferior TG. To the extent that semantic errors, phonological errors and delayed responses reflect disruptions in different processes, our results imply topographical specialization of semantic and phonological processing. Specifically, results revealed an inferior-to-superior gradient, with more superior regions associated with phonological processing. Further, errors were increasingly semantically related to targets toward posterior temporal cortex. We speculate that detailed semantic input is needed to support phonological retrieval, and thus, the specificity of semantic input increases progressively toward posterior temporal regions implicated in phonological processing. Hum Brain Mapp 38:688-703, 2017. © 2016 Wiley Periodicals, Inc.
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Affiliation(s)
| | - Alicia C Williams
- Department of Neurology, Columbia University Medical Center, New York
| | - Guy M McKhann
- Department of Neurology, Columbia University Medical Center, New York
| | - Marla J Hamberger
- Department of Neurology, Columbia University Medical Center, New York
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258
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Mollo G, Karapanagiotidis T, Bernhardt BC, Murphy CE, Smallwood J, Jefferies E. An individual differences analysis of the neurocognitive architecture of the semantic system at rest. Brain Cogn 2016; 109:112-123. [PMID: 27662589 PMCID: PMC5090046 DOI: 10.1016/j.bandc.2016.07.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2016] [Revised: 07/07/2016] [Accepted: 07/08/2016] [Indexed: 02/08/2023]
Abstract
Efficient semantic cognition depends on accessing and selecting conceptual knowledge relevant to the current task or context. This study explored the neurocognitive architecture that supports this function by examining how individual variation in functional brain organisation predicts comprehension and semantic generation. Participants underwent resting state functional magnetic resonance imaging (fMRI) and, on separate days, performed written synonym judgement, and letter and category fluency tasks. We found that better synonym judgement for high frequency items was linked to greater functional coupling between posterior fusiform and anterior superior temporal cortex (aSTG), which might index orthographic-to-semantic access. However, stronger coupling between aSTG and ventromedial prefrontal cortex was associated with poor performance on the same trials, potentially reflecting greater difficulty in focussing retrieval on relevant features for high frequency items that appear in a greater range of contexts. Fluency performance was instead linked to variations in the functional coupling of the inferior frontal gyrus (IFG); anterior IFG was more coupled to regions of primary visual cortex for individuals who were good at category fluency, while poor letter fluency was predicted by stronger coupling between posterior IFG and retrosplenial cortex. These results show that individual differences in functional connectivity at rest predict semantic performance and are consistent with a component process account of semantic cognition in which representational information is shaped by control processes to fit the current requirements, in both comprehension and fluency tasks.
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Affiliation(s)
- Giovanna Mollo
- Department of Psychology and York Neuroimaging Centre, University of York, Heslington, York, United Kingdom.
| | - Theodoros Karapanagiotidis
- Department of Psychology and York Neuroimaging Centre, University of York, Heslington, York, United Kingdom
| | - Boris C Bernhardt
- McConnell Brain Imaging Centre, Montreal Neurological Institute, McGill University, Montreal, QC, Canada
| | - Charlotte E Murphy
- Department of Psychology and York Neuroimaging Centre, University of York, Heslington, York, United Kingdom
| | - Jonathan Smallwood
- Department of Psychology and York Neuroimaging Centre, University of York, Heslington, York, United Kingdom
| | - Elizabeth Jefferies
- Department of Psychology and York Neuroimaging Centre, University of York, Heslington, York, United Kingdom
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259
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Hallam GP, Whitney C, Hymers M, Gouws AD, Jefferies E. Charting the effects of TMS with fMRI: Modulation of cortical recruitment within the distributed network supporting semantic control. Neuropsychologia 2016; 93:40-52. [PMID: 27650816 PMCID: PMC5155664 DOI: 10.1016/j.neuropsychologia.2016.09.012] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Revised: 09/15/2016] [Accepted: 09/16/2016] [Indexed: 11/15/2022]
Abstract
Semantic memory comprises our knowledge of the meanings of words and objects but only some of this knowledge is relevant at any given time. Thus, semantic control processes are needed to focus retrieval on relevant information. Research on the neural basis of semantic control has strongly implicated left inferior frontal gyrus (LIFG) but recent work suggests that a wider network supports semantic control, including left posterior middle temporal gyrus (pMTG), right inferior frontal gyrus (RIFG) and pre-supplementary motor area (pre-SMA). In the current study, we used repetitive transcranial magnetic stimulation (1 Hz offline TMS) over LIFG, immediately followed by fMRI, to examine modulation of the semantic network. We compared the effect of stimulation on judgements about strongly-associated words (dog-bone) and weaker associations (dog-beach), since previous studies have found that dominant links can be recovered largely automatically with little engagement of LIFG, while more distant connections require greater control. Even though behavioural performance was maintained in response to TMS, LIFG stimulation increased the effect of semantic control demands in pMTG and pre-SMA, relative to stimulation of a control site (occipital pole). These changes were accompanied by reduced recruitment of both the stimulated region (LIFG) and its right hemisphere homologue (RIFG), particularly for strong associations with low control requirements. Thus repetitive TMS to LIFG modulated the contribution of distributed regions to semantic judgements in two distinct ways. Offline rTMS was used to modulate the semantic control system. fMRI revealed post-stimulation changes in other areas of the semantic control system. Semantic retrieval requires the flexible activation of representations shaped by control processes.
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Affiliation(s)
- Glyn P Hallam
- Department of Psychology and York Neuroimaging Centre, University of York, YO10 5DD York, UK.
| | - Carin Whitney
- Department of Psychology and York Neuroimaging Centre, University of York, YO10 5DD York, UK
| | - Mark Hymers
- Department of Psychology and York Neuroimaging Centre, University of York, YO10 5DD York, UK
| | - Andre D Gouws
- Department of Psychology and York Neuroimaging Centre, University of York, YO10 5DD York, UK
| | - Elizabeth Jefferies
- Department of Psychology and York Neuroimaging Centre, University of York, YO10 5DD York, UK
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260
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Hoffman P. The meaning of 'life' and other abstract words: Insights from neuropsychology. J Neuropsychol 2016; 10:317-43. [PMID: 25708527 PMCID: PMC5026063 DOI: 10.1111/jnp.12065] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2014] [Revised: 01/09/2015] [Indexed: 01/15/2023]
Abstract
There are a number of long-standing theories on how the cognitive processing of abstract words, like 'life', differs from that of concrete words, like 'knife'. This review considers current perspectives on this debate, focusing particularly on insights obtained from patients with language disorders and integrating these with evidence from functional neuroimaging studies. The evidence supports three distinct and mutually compatible hypotheses. (1) Concrete and abstract words differ in their representational substrates, with concrete words depending particularly on sensory experiences and abstract words on linguistic, emotional, and magnitude-based information. Differential dependence on visual versus verbal experience is supported by the evidence for graded specialization in the anterior temporal lobes for concrete versus abstract words. In addition, concrete words have richer representations, in line with better processing of these words in most aphasic patients and, in particular, patients with semantic dementia. (2) Abstract words place greater demands on executive regulation processes because they have variable meanings that change with context. This theory explains abstract word impairments in patients with semantic-executive deficits and is supported by neuroimaging studies showing greater response to abstract words in inferior prefrontal cortex. (3) The relationships between concrete words are governed primarily by conceptual similarity, while those of abstract words depend on association to a greater degree. This theory, based primarily on interference and priming effects in aphasic patients, is the most recent to emerge and the least well understood. I present analyses indicating that patterns of lexical co-occurrence may be important in understanding these effects.
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Affiliation(s)
- Paul Hoffman
- Neuroscience and Aphasia Research Unit (NARU)University of ManchesterUK
- Centre for Cognitive Ageing and Cognitive Epidemiology (CCACE)Department of PsychologyUniversity of EdinburghUK
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261
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Bzdok D, Hartwigsen G, Reid A, Laird AR, Fox PT, Eickhoff SB. Left inferior parietal lobe engagement in social cognition and language. Neurosci Biobehav Rev 2016; 68:319-334. [PMID: 27241201 PMCID: PMC5441272 DOI: 10.1016/j.neubiorev.2016.02.024] [Citation(s) in RCA: 119] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Revised: 02/24/2016] [Accepted: 02/25/2016] [Indexed: 10/21/2022]
Abstract
Social cognition and language are two core features of the human species. Despite distributed recruitment of brain regions in each mental capacity, the left parietal lobe (LPL) represents a zone of topographical convergence. The present study quantitatively summarizes hundreds of neuroimaging studies on social cognition and language. Using connectivity-based parcellation on a meta-analytically defined volume of interest (VOI), regional coactivation patterns within this VOI allowed identifying distinct subregions. Across parcellation solutions, two clusters emerged consistently in rostro-ventral and caudo-ventral aspects of the parietal VOI. Both clusters were functionally significantly associated with social-cognitive and language processing. In particular, the rostro-ventral cluster was associated with lower-level processing facets, while the caudo-ventral cluster was associated with higher-level processing facets in both mental capacities. Contrarily, in the (less stable) dorsal parietal VOI, all clusters reflected computation of general-purpose processes, such as working memory and matching tasks, that are frequently co-recruited by social or language processes. Our results hence favour a rostro-caudal distinction of lower- versus higher-level processes underlying social cognition and language in the left inferior parietal lobe.
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Affiliation(s)
- Danilo Bzdok
- Department of Psychiatry, Psychotherapy and Psychosomatics, RWTH Aachen University, Germany; JARA, Translational Brain Medicine, Aachen, Germany; Institute of Neuroscience and Medicine (INM-1), Research Center Jülich, Jülich, Germany; Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University, Düsseldorf, Germany; Parietal team, INRIA, Neurospin, bat 145, CEA Saclay, 91191 Gif-sur-Yvette, France.
| | - Gesa Hartwigsen
- Department of Neuropsychology, Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Leipzig, Germany
| | - Andrew Reid
- Institute of Neuroscience and Medicine (INM-1), Research Center Jülich, Jülich, Germany
| | - Angela R Laird
- Department of Physics, Florida International University, USA
| | - Peter T Fox
- Research Imaging Institute, University of Texas Health Science Center, San Antonio, TX, USA
| | - Simon B Eickhoff
- Institute of Neuroscience and Medicine (INM-1), Research Center Jülich, Jülich, Germany; Institute of Clinical Neuroscience and Medical Psychology, Heinrich Heine University, Düsseldorf, Germany
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262
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Herbet G, Moritz-Gasser S, Duffau H. Direct evidence for the contributive role of the right inferior fronto-occipital fasciculus in non-verbal semantic cognition. Brain Struct Funct 2016; 222:1597-1610. [PMID: 27568379 DOI: 10.1007/s00429-016-1294-x] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 08/17/2016] [Indexed: 11/29/2022]
Abstract
The neural foundations underlying semantic processing have been extensively investigated, highlighting a pivotal role of the ventral stream. However, although studies concerning the involvement of the left ventral route in verbal semantics are proficient, the potential implication of the right ventral pathway in non-verbal semantics has been to date unexplored. To gain insights on this matter, we used an intraoperative direct electrostimulation to map the structures mediating the non-verbal semantic system in the right hemisphere. Thirteen patients presenting with a right low-grade glioma located within or close to the ventral stream were included. During the 'awake' procedure, patients performed both a visual non-verbal semantic task and a verbal (control) task. At the cortical level, in the right hemisphere, we found non-verbal semantic-related sites (n = 7 in 6 patients) in structures commonly associated with verbal semantic processes in the left hemisphere, including the superior temporal gyrus, the pars triangularis, and the dorsolateral prefrontal cortex. At the subcortical level, we found non-verbal semantic-related sites in all but one patient (n = 15 sites in 12 patients). Importantly, all these responsive stimulation points were located on the spatial course of the right inferior fronto-occipital fasciculus (IFOF). These findings provide direct support for a critical role of the right IFOF in non-verbal semantic processing. Based upon these original data, and in connection with previous findings showing the involvement of the left IFOF in non-verbal semantic processing, we hypothesize the existence of a bilateral network underpinning the non-verbal semantic system, with a homotopic connectional architecture.
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Affiliation(s)
- Guillaume Herbet
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, 80 Avenue Augustin Fliche, 34295, Montpellier, France. .,National Institute for Health and Medical Research (INSERM), U1051, Team "Plasticity of the Central Nervous System, Human Stem Cells and Glial Tumors", Institute for Neurosciences of Montpellier, Montpellier University Medical Center, 80 Av Augustin Fliche, 34091, Montpellier, France. .,University of Montpellier, 163 rue Auguste Broussonnet, 34090, Montpellier, France.
| | - Sylvie Moritz-Gasser
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, 80 Avenue Augustin Fliche, 34295, Montpellier, France.,National Institute for Health and Medical Research (INSERM), U1051, Team "Plasticity of the Central Nervous System, Human Stem Cells and Glial Tumors", Institute for Neurosciences of Montpellier, Montpellier University Medical Center, 80 Av Augustin Fliche, 34091, Montpellier, France.,University of Montpellier, 163 rue Auguste Broussonnet, 34090, Montpellier, France
| | - Hugues Duffau
- Department of Neurosurgery, Gui de Chauliac Hospital, Montpellier University Medical Center, 80 Avenue Augustin Fliche, 34295, Montpellier, France.,National Institute for Health and Medical Research (INSERM), U1051, Team "Plasticity of the Central Nervous System, Human Stem Cells and Glial Tumors", Institute for Neurosciences of Montpellier, Montpellier University Medical Center, 80 Av Augustin Fliche, 34091, Montpellier, France.,University of Montpellier, 163 rue Auguste Broussonnet, 34090, Montpellier, France
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263
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A Neuropsychological Perspective on Abstract Word Representation: From Theory to Treatment of Acquired Language Disorders. Curr Neurol Neurosci Rep 2016; 16:79. [PMID: 27443646 DOI: 10.1007/s11910-016-0683-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Natural languages are rife with words that describe feelings, introspective states, and social constructs (e.g., liberty, persuasion) that cannot be directly observed through the senses. Effective communication demands linguistic competence with such abstract words. In clinical neurological settings, abstract words are especially vulnerable to the effects of stroke and neurodegenerative conditions such as Alzheimer's disease. A parallel literature in cognitive neuroscience suggests that abstract and concrete words are at least partially neuroanatomically dissociable. Much remains to be learned about the nature of lexical-semantic deficits of abstract words and how best to promote their recovery. Here, we review contemporary theoretical approaches to abstract-concrete word representation with an aim toward contextualizing patient-based dissociations for abstract words. We then describe a burgeoning treatment approach for targeting abstract words and suggest a number of potential strategies for future interventions. We argue that a deeper understanding of is essential for informing language rehabilitation.
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264
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Ishibashi R, Pobric G, Saito S, Lambon Ralph MA. The neural network for tool-related cognition: An activation likelihood estimation meta-analysis of 70 neuroimaging contrasts. Cogn Neuropsychol 2016; 33:241-56. [PMID: 27362967 PMCID: PMC4989859 DOI: 10.1080/02643294.2016.1188798] [Citation(s) in RCA: 51] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
The ability to recognize and use a variety of tools is an intriguing human cognitive function. Multiple neuroimaging studies have investigated neural activations with various types of tool-related tasks. In the present paper, we reviewed tool-related neural activations reported in 70 contrasts from 56 neuroimaging studies and performed a series of activation likelihood estimation (ALE) meta-analyses to identify tool-related cortical circuits dedicated either to general tool knowledge or to task-specific processes. The results indicate the following: (a) Common, task-general processing regions for tools are located in the left inferior parietal lobule (IPL) and ventral premotor cortex; and (b) task-specific regions are located in superior parietal lobule (SPL) and dorsal premotor area for imagining/executing actions with tools and in bilateral occipito-temporal cortex for recognizing/naming tools. The roles of these regions in task-general and task-specific activities are discussed with reference to evidence from neuropsychology, experimental psychology and other neuroimaging studies.
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Affiliation(s)
- Ryo Ishibashi
- a Neuroscience and Aphasia Research Unit, School of Psychological Sciences , University of Manchester , Manchester , UK.,b Human Brain Research Center, School of Medicine , Kyoto University , Kyoto , Japan
| | - Gorana Pobric
- a Neuroscience and Aphasia Research Unit, School of Psychological Sciences , University of Manchester , Manchester , UK
| | - Satoru Saito
- a Neuroscience and Aphasia Research Unit, School of Psychological Sciences , University of Manchester , Manchester , UK.,c Department of Cognitive Psychology in Education , Kyoto University , Kyoto , Japan
| | - Matthew A Lambon Ralph
- a Neuroscience and Aphasia Research Unit, School of Psychological Sciences , University of Manchester , Manchester , UK
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265
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Shallice T. Cognitive neuropsychology and its vicissitudes: The fate of Caramazza's axioms. Cogn Neuropsychol 2016; 32:385-411. [DOI: 10.1080/02643294.2015.1131677] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
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266
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Preisig BC, Eggenberger N, Zito G, Vanbellingen T, Schumacher R, Hopfner S, Gutbrod K, Nyffeler T, Cazzoli D, Annoni JM, Bohlhalter S, Müri RM. Eye Gaze Behavior at Turn Transition: How Aphasic Patients Process Speakers' Turns during Video Observation. J Cogn Neurosci 2016; 28:1613-24. [PMID: 27243612 DOI: 10.1162/jocn_a_00983] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The human turn-taking system regulates the smooth and precise exchange of speaking turns during face-to-face interaction. Recent studies investigated the processing of ongoing turns during conversation by measuring the eye movements of noninvolved observers. The findings suggest that humans shift their gaze in anticipation to the next speaker before the start of the next turn. Moreover, there is evidence that the ability to timely detect turn transitions mainly relies on the lexico-syntactic content provided by the conversation. Consequently, patients with aphasia, who often experience deficits in both semantic and syntactic processing, might encounter difficulties to detect and timely shift their gaze at turn transitions. To test this assumption, we presented video vignettes of natural conversations to aphasic patients and healthy controls, while their eye movements were measured. The frequency and latency of event-related gaze shifts, with respect to the end of the current turn in the videos, were compared between the two groups. Our results suggest that, compared with healthy controls, aphasic patients have a reduced probability to shift their gaze at turn transitions but do not show significantly increased gaze shift latencies. In healthy controls, but not in aphasic patients, the probability to shift the gaze at turn transition was increased when the video content of the current turn had a higher lexico-syntactic complexity. Furthermore, the results from voxel-based lesion symptom mapping indicate that the association between lexico-syntactic complexity and gaze shift latency in aphasic patients is predicted by brain lesions located in the posterior branch of the left arcuate fasciculus. Higher lexico-syntactic processing demands seem to lead to a reduced gaze shift probability in aphasic patients. This finding may represent missed opportunities for patients to place their contributions during everyday conversation.
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Affiliation(s)
| | | | | | | | | | - Simone Hopfner
- University Hospital Inselspital Bern.,University of Bern
| | | | | | | | | | | | - René M Müri
- University Hospital Inselspital Bern.,University of Bern
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267
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Exploring the role of the posterior middle temporal gyrus in semantic cognition: Integration of anterior temporal lobe with executive processes. Neuroimage 2016; 137:165-177. [PMID: 27236083 PMCID: PMC4927261 DOI: 10.1016/j.neuroimage.2016.05.051] [Citation(s) in RCA: 234] [Impact Index Per Article: 29.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2016] [Revised: 04/26/2016] [Accepted: 05/21/2016] [Indexed: 11/22/2022] Open
Abstract
Making sense of the world around us depends upon selectively retrieving information relevant to our current goal or context. However, it is unclear whether selective semantic retrieval relies exclusively on general control mechanisms recruited in demanding non-semantic tasks, or instead on systems specialised for the control of meaning. One hypothesis is that the left posterior middle temporal gyrus (pMTG) is important in the controlled retrieval of semantic (not non-semantic) information; however this view remains controversial since a parallel literature links this site to event and relational semantics. In a functional neuroimaging study, we demonstrated that an area of pMTG implicated in semantic control by a recent meta-analysis was activated in a conjunction of (i) semantic association over size judgements and (ii) action over colour feature matching. Under these circumstances the same region showed functional coupling with the inferior frontal gyrus — another crucial site for semantic control. Structural and functional connectivity analyses demonstrated that this site is at the nexus of networks recruited in automatic semantic processing (the default mode network) and executively demanding tasks (the multiple-demand network). Moreover, in both task and task-free contexts, pMTG exhibited functional properties that were more similar to ventral parts of inferior frontal cortex, implicated in controlled semantic retrieval, than more dorsal inferior frontal sulcus, implicated in domain-general control. Finally, the pMTG region was functionally correlated at rest with other regions implicated in control-demanding semantic tasks, including inferior frontal gyrus and intraparietal sulcus. We suggest that pMTG may play a crucial role within a large-scale network that allows the integration of automatic retrieval in the default mode network with executively-demanding goal-oriented cognition, and that this could support our ability to understand actions and non-dominant semantic associations, allowing semantic retrieval to be ‘shaped’ to suit a task or context. Posterior middle temporal gyrus supports semantic control and event semantics. pMTG is at nexus of the default mode and multiple-demand networks. It links anterior temporal and prefrontal regions for representation and control. pMTG connects with inferior frontal gyrus during tasks and at rest. These sites form a semantic control network distinct from executive control.
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268
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Thompson HE, Henshall L, Jefferies E. The role of the right hemisphere in semantic control: A case-series comparison of right and left hemisphere stroke. Neuropsychologia 2016; 85:44-61. [PMID: 26945505 PMCID: PMC4863527 DOI: 10.1016/j.neuropsychologia.2016.02.030] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2015] [Revised: 02/28/2016] [Accepted: 02/29/2016] [Indexed: 11/30/2022]
Abstract
Semantic control processes guide conceptual retrieval so that we are able to focus on non-dominant associations and features when these are required for the task or context, yet the neural basis of semantic control is not fully understood. Neuroimaging studies have emphasised the role of left inferior frontal gyrus (IFG) in controlled retrieval, while neuropsychological investigations of semantic control deficits have almost exclusively focussed on patients with left-sided damage (e.g., patients with semantic aphasia, SA). Nevertheless, activation in fMRI during demanding semantic tasks typically extends to right IFG. To investigate the role of the right hemisphere (RH) in semantic control, we compared nine RH stroke patients with 21 left-hemisphere SA patients, 11 mild SA cases and 12 healthy, aged-matched controls on semantic and executive tasks, plus experimental tasks that manipulated semantic control in paradigms particularly sensitive to RH damage. RH patients had executive deficits to parallel SA patients but they performed well on standard semantic tests. Nevertheless, multimodal semantic control deficits were found in experimental tasks involving facial emotions and the 'summation' of meaning across multiple items. On these tasks, RH patients showed effects similar to those in SA cases - multimodal deficits that were sensitive to distractor strength and cues and miscues, plus increasingly poor performance in cyclical matching tasks which repeatedly probed the same set of concepts. Thus, despite striking differences in single-item comprehension, evidence presented here suggests semantic control is bilateral, and disruption of this component of semantic cognition can be seen following damage to either hemisphere.
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Affiliation(s)
- Hannah E Thompson
- Department of Psychology and York Neuroimaging Centre, University of York, UK.
| | - Lauren Henshall
- Department of Psychology and York Neuroimaging Centre, University of York, UK
| | - Elizabeth Jefferies
- Department of Psychology and York Neuroimaging Centre, University of York, UK
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269
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Role of features and categories in the organization of object knowledge: Evidence from adaptation fMRI. Cortex 2016; 78:174-194. [DOI: 10.1016/j.cortex.2016.01.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 12/11/2015] [Accepted: 01/05/2016] [Indexed: 11/29/2022]
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270
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van Dam WO, Desai RH. The Semantics of Syntax: The Grounding of Transitive and Intransitive Constructions. J Cogn Neurosci 2016; 28:693-709. [DOI: 10.1162/jocn_a_00926] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
Abstract
Embodied theories of language maintain that brain areas associated with perception and action are also involved in the processing and representation of word meaning. A number of studies have shown that sentences with action verbs elicit activation within sensory–motor brain regions, arguing that sentence-induced mental simulations provide a means for grounding their lexical-semantic meaning. Constructionist theories argue, however, that form–meaning correspondence is present not only at the lexical level but also at the level of constructions. We investigated whether sentence-induced motor resonance is present for syntactic constructions. We measured the BOLD signal while participants read sentences with (di)transitive (caused motion) or intransitive constructions that contained either action or abstract verbs. The results showed a distinct neuronal signature for caused motion and intransitive syntactic frames. Caused motion frames activated regions associated with reaching and grasping actions, including the left anterior intraparietal sulcus and the parietal reach region. Intransitive frames activated lateral temporal regions commonly associated with abstract word processing. The left pars orbitalis showed an interaction between the syntactic frame and verb class. These findings show that sensory–motor activation elicited by sentences entails both motor resonance evoked by single words as well as at the level of syntactic constructions.
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271
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Halai AD, Woollams AM, Lambon Ralph MA. Using principal component analysis to capture individual differences within a unified neuropsychological model of chronic post-stroke aphasia: Revealing the unique neural correlates of speech fluency, phonology and semantics. Cortex 2016; 86:275-289. [PMID: 27216359 PMCID: PMC5264368 DOI: 10.1016/j.cortex.2016.04.016] [Citation(s) in RCA: 104] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Revised: 04/15/2016] [Accepted: 04/18/2016] [Indexed: 12/16/2022]
Abstract
Individual differences in the performance profiles of neuropsychologically-impaired patients are pervasive yet there is still no resolution on the best way to model and account for the variation in their behavioural impairments and the associated neural correlates. To date, researchers have generally taken one of three different approaches: a single-case study methodology in which each case is considered separately; a case-series design in which all individual patients from a small coherent group are examined and directly compared; or, group studies, in which a sample of cases are investigated as one group with the assumption that they are drawn from a homogenous category and that performance differences are of no interest. In recent research, we have developed a complementary alternative through the use of principal component analysis (PCA) of individual data from large patient cohorts. This data-driven approach not only generates a single unified model for the group as a whole (expressed in terms of the emergent principal components) but is also able to capture the individual differences between patients (in terms of their relative positions along the principal behavioural axes). We demonstrate the use of this approach by considering speech fluency, phonology and semantics in aphasia diagnosis and classification, as well as their unique neural correlates. PCA of the behavioural data from 31 patients with chronic post-stroke aphasia resulted in four statistically-independent behavioural components reflecting phonological, semantic, executive-cognitive and fluency abilities. Even after accounting for lesion volume, entering the four behavioural components simultaneously into a voxel-based correlational methodology (VBCM) analysis revealed that speech fluency (speech quanta) was uniquely correlated with left motor cortex and underlying white matter (including the anterior section of the arcuate fasciculus and the frontal aslant tract), phonological skills with regions in the superior temporal gyrus and pars opercularis, and semantics with the anterior temporal stem.
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Affiliation(s)
- Ajay D Halai
- Neuroscience and Aphasia Research Unit, University of Manchester, UK.
| | - Anna M Woollams
- Neuroscience and Aphasia Research Unit, University of Manchester, UK
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272
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Holderbaum CS, Mansur LL, de Salles JF. Heterogeneity in semantic priming effect with a lexical decision task in patients after left hemisphere stroke. Dement Neuropsychol 2016; 10:91-97. [PMID: 29213439 PMCID: PMC5642399 DOI: 10.1590/s1980-5764-2016dn1002004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2015] [Accepted: 01/16/2016] [Indexed: 11/22/2022] Open
Abstract
Investigations on the semantic priming effect (SPE) in patients after left hemisphere (LH) lesions have shown disparities that may be explained by the variability in performance found among patients. The aim of the present study was to verify the existence of subgroups of patients after LH stroke by searching for dissociations between performance on the lexical decision task based on the semantic priming paradigm and performance on direct memory, semantic association and language tasks. All 17 patients with LH lesions after stroke (ten non-fluent aphasics and seven non aphasics) were analyzed individually. Results indicated the presence of three groups of patients according to SPE: one exhibiting SPE at both stimulus onset asynchronies (SOAs), one with SPE only at long SOA, and another, larger group with no SPE.
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Affiliation(s)
- Candice Steffen Holderbaum
- PhD in Psychology (UFRGS) - Post-Graduation Program in Psychology, Federal University of Rio Grande do Sul (UFRGS)
| | - Letícia Lessa Mansur
- PhD in Linguistics (University of São Paulo) - Associate Professor of the University of São Paulo
| | - Jerusa Fumagalli de Salles
- PhD in Psychology (UFRGS) - Associate Professor on the Post-Graduation Program in Psychology, Federal University of Rio Grande do Sul (UFRGS)
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273
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Meier EL, Kapse KJ, Kiran S. The Relationship between Frontotemporal Effective Connectivity during Picture Naming, Behavior, and Preserved Cortical Tissue in Chronic Aphasia. Front Hum Neurosci 2016; 10:109. [PMID: 27014039 PMCID: PMC4792868 DOI: 10.3389/fnhum.2016.00109] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 02/29/2016] [Indexed: 11/17/2022] Open
Abstract
While several studies of task-based effective connectivity of normal language processing exist, little is known about the functional reorganization of language networks in patients with stroke-induced chronic aphasia. During oral picture naming, activation in neurologically intact individuals is found in "classic" language regions involved with retrieval of lexical concepts [e.g., left middle temporal gyrus (LMTG)], word form encoding [e.g., left posterior superior temporal gyrus, (LpSTG)], and controlled retrieval of semantic and phonological information [e.g., left inferior frontal gyrus (LIFG)] as well as domain-general regions within the multiple demands network [e.g., left middle frontal gyrus (LMFG)]. After stroke, lesions to specific parts of the left hemisphere language network force reorganization of this system. While individuals with aphasia have been found to recruit similar regions for language tasks as healthy controls, the relationship between the dynamic functioning of the language network and individual differences in underlying neural structure and behavioral performance is still unknown. Therefore, in the present study, we used dynamic causal modeling (DCM) to investigate differences between individuals with aphasia and healthy controls in terms of task-induced regional interactions between three regions (i.e., LIFG, LMFG, and LMTG) vital for picture naming. The DCM model space was organized according to exogenous input to these regions and partitioned into separate families. At the model level, random effects family wise Bayesian Model Selection revealed that models with driving input to LIFG best fit the control data whereas models with driving input to LMFG best fit the patient data. At the parameter level, a significant between-group difference in the connection strength from LMTG to LIFG was seen. Within the patient group, several significant relationships between network connectivity parameters, spared cortical tissue, and behavior were observed. Overall, this study provides some preliminary findings regarding how neural networks for language reorganize for individuals with aphasia and how brain connectivity relates to underlying structural integrity and task performance.
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Affiliation(s)
- Erin L. Meier
- Department of Speech Language and Hearing Sciences, Aphasia Research Laboratory, Sargent College, Boston University, BostonMA, USA
| | | | - Swathi Kiran
- Department of Speech Language and Hearing Sciences, Aphasia Research Laboratory, Sargent College, Boston University, BostonMA, USA
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274
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Chen Y, Shimotake A, Matsumoto R, Kunieda T, Kikuchi T, Miyamoto S, Fukuyama H, Takahashi R, Ikeda A, Lambon Ralph MA. The 'when' and 'where' of semantic coding in the anterior temporal lobe: Temporal representational similarity analysis of electrocorticogram data. Cortex 2016; 79:1-13. [PMID: 27085891 PMCID: PMC4884671 DOI: 10.1016/j.cortex.2016.02.015] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2015] [Revised: 12/18/2015] [Accepted: 03/01/2016] [Indexed: 10/28/2022]
Abstract
Electrocorticograms (ECoG) provide a unique opportunity to monitor neural activity directly at the cortical surface. Ten patients with subdural electrodes covering ventral and lateral anterior temporal regions (ATL) performed a picture naming task. Temporal representational similarity analysis (RSA) was used, for the first time, to compare spatio-temporal neural patterns from the ATL surface with pre-defined theoretical models. The results indicate that the neural activity in the ventral subregion of the ATL codes semantic representations from 250 msec after picture onset. The observed activation similarity was not related to the visual similarity of the pictures or the phonological similarity of their names. In keeping with convergent evidence for the importance of the ATL in semantic processing, these results provide the first direct evidence of semantic coding from the surface of the ventral ATL and its time-course.
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Affiliation(s)
- Y Chen
- Neuroscience and Aphasia Research Unit, School of Psychological Sciences, University of Manchester, Manchester, UK
| | - A Shimotake
- Department of Neurology, Graduate School of Medicine, Kyoto University, Japan
| | - R Matsumoto
- Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto University, Japan.
| | - T Kunieda
- Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Japan
| | - T Kikuchi
- Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Japan
| | - S Miyamoto
- Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Japan
| | - H Fukuyama
- Human Brain Research Center, Graduate School of Medicine, Kyoto University, Japan
| | - R Takahashi
- Department of Neurology, Graduate School of Medicine, Kyoto University, Japan
| | - A Ikeda
- Department of Epilepsy, Movement Disorders and Physiology, Graduate School of Medicine, Kyoto University, Japan
| | - M A Lambon Ralph
- Neuroscience and Aphasia Research Unit, School of Psychological Sciences, University of Manchester, Manchester, UK.
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275
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Automatic and Controlled Semantic Retrieval: TMS Reveals Distinct Contributions of Posterior Middle Temporal Gyrus and Angular Gyrus. J Neurosci 2016; 35:15230-9. [PMID: 26586812 DOI: 10.1523/jneurosci.4705-14.2015] [Citation(s) in RCA: 136] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Semantic retrieval involves both (1) automatic spreading activation between highly related concepts and (2) executive control processes that tailor this activation to suit the current context or goals. Two structures in left temporoparietal cortex, angular gyrus (AG) and posterior middle temporal gyrus (pMTG), are thought to be crucial to semantic retrieval and are often recruited together during semantic tasks; however, they show strikingly different patterns of functional connectivity at rest (coupling with the "default mode network" and "frontoparietal control system," respectively). Here, transcranial magnetic stimulation (TMS) was used to establish a causal yet dissociable role for these sites in semantic cognition in human volunteers. TMS to AG disrupted thematic judgments particularly when the link between probe and target was strong (e.g., a picture of an Alsatian with a bone), and impaired the identification of objects at a specific but not a superordinate level (for the verbal label "Alsatian" not "animal"). In contrast, TMS to pMTG disrupted thematic judgments for weak but not strong associations (e.g., a picture of an Alsatian with razor wire), and impaired identity matching for both superordinate and specific-level labels. Thus, stimulation to AG interfered with the automatic retrieval of specific concepts from the semantic store while stimulation of pMTG impaired semantic cognition when there was a requirement to flexibly shape conceptual activation in line with the task requirements. These results demonstrate that AG and pMTG make a dissociable contribution to automatic and controlled aspects of semantic retrieval. SIGNIFICANCE STATEMENT We demonstrate a novel functional dissociation between the angular gyrus (AG) and posterior middle temporal gyrus (pMTG) in conceptual processing. These sites are often coactivated during neuroimaging studies using semantic tasks, but their individual contributions are unclear. Using transcranial magnetic stimulation and tasks designed to assess different aspects of semantics (item identity and thematic matching), we tested two alternative theoretical accounts. Neither site showed the pattern expected for a "thematic hub" (i.e., a site storing associations between concepts) since stimulation disrupted both tasks. Instead, the data indicated that pMTG contributes to the controlled retrieval of conceptual knowledge, while AG is critical for the efficient automatic retrieval of specific semantic information.
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276
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Schwartz MF, Middleton EL, Brecher A, Gagliardi M, Garvey K. Does naming accuracy improve through self-monitoring of errors? Neuropsychologia 2016; 84:272-81. [PMID: 26863091 DOI: 10.1016/j.neuropsychologia.2016.01.027] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Revised: 11/24/2015] [Accepted: 01/21/2016] [Indexed: 10/22/2022]
Abstract
This study examined spontaneous self-monitoring of picture naming in people with aphasia. Of primary interest was whether spontaneous detection or repair of an error constitutes an error signal or other feedback that tunes the production system to the desired outcome. In other words, do acts of monitoring cause adaptive change in the language system? A second possibility, not incompatible with the first, is that monitoring is indicative of an item's representational strength, and strength is a causal factor in language change. Twelve PWA performed a 615-item naming test twice, in separate sessions, without extrinsic feedback. At each timepoint, we scored the first complete response for accuracy and error type and the remainder of the trial for verbalizations consistent with detection (e.g., "no, not that") and successful repair (i.e., correction). Data analysis centered on: (a) how often an item that was misnamed at one timepoint changed to correct at the other timepoint, as a function of monitoring; and (b) how monitoring impacted change scores in the Forward (Time 1 to Time 2) compared to Backward (Time 2 to Time 1) direction. The Strength hypothesis predicts significant effects of monitoring in both directions. The Learning hypothesis predicts greater effects in the Forward direction. These predictions were evaluated for three types of errors--Semantic errors, Phonological errors, and Fragments--using mixed-effects regression modeling with crossed random effects. Support for the Strength hypothesis was found for all three error types. Support for the Learning hypothesis was found for Semantic errors. All effects were due to error repair, not error detection. We discuss the theoretical and clinical implications of these novel findings.
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Affiliation(s)
| | | | - Adelyn Brecher
- Moss Rehabilitation Research Institute, Elkins Park, PA, USA
| | | | - Kelly Garvey
- Moss Rehabilitation Research Institute, Elkins Park, PA, USA
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277
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Comprehension of Co-Speech Gestures in Aphasic Patients: An Eye Movement Study. PLoS One 2016; 11:e0146583. [PMID: 26735917 PMCID: PMC4703302 DOI: 10.1371/journal.pone.0146583] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2015] [Accepted: 12/18/2015] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Co-speech gestures are omnipresent and a crucial element of human interaction by facilitating language comprehension. However, it is unclear whether gestures also support language comprehension in aphasic patients. Using visual exploration behavior analysis, the present study aimed to investigate the influence of congruence between speech and co-speech gestures on comprehension in terms of accuracy in a decision task. METHOD Twenty aphasic patients and 30 healthy controls watched videos in which speech was either combined with meaningless (baseline condition), congruent, or incongruent gestures. Comprehension was assessed with a decision task, while remote eye-tracking allowed analysis of visual exploration. RESULTS In aphasic patients, the incongruent condition resulted in a significant decrease of accuracy, while the congruent condition led to a significant increase in accuracy compared to baseline accuracy. In the control group, the incongruent condition resulted in a decrease in accuracy, while the congruent condition did not significantly increase the accuracy. Visual exploration analysis showed that patients fixated significantly less on the face and tended to fixate more on the gesturing hands compared to controls. CONCLUSION Co-speech gestures play an important role for aphasic patients as they modulate comprehension. Incongruent gestures evoke significant interference and deteriorate patients' comprehension. In contrast, congruent gestures enhance comprehension in aphasic patients, which might be valuable for clinical and therapeutic purposes.
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278
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Seckin M, Mesulam MM, Rademaker AW, Voss JL, Weintraub S, Rogalski EJ, Hurley RS. Eye movements as probes of lexico-semantic processing in a patient with primary progressive aphasia. Neurocase 2016; 22:65-75. [PMID: 25982291 PMCID: PMC4651860 DOI: 10.1080/13554794.2015.1045523] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Eye movement trajectories during a verbally cued object search task were used as probes of lexico-semantic associations in an anomic patient with primary progressive aphasia. Visual search was normal on trials where the target object could be named but became lengthy and inefficient on trials where the object failed to be named. The abnormality was most profound if the noun denoting the object could not be recognized. Even trials where the name of the target object was recognized but not retrieved triggered abnormal eye movements, demonstrating that retrieval failures can have underlying associative components despite intact comprehension of the corresponding noun.
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Affiliation(s)
- Mustafa Seckin
- a Cognitive Neurology and Alzheimer's Disease Center , Northwestern University , Chicago , IL , USA
| | - M-Marsel Mesulam
- a Cognitive Neurology and Alzheimer's Disease Center , Northwestern University , Chicago , IL , USA
| | - Alfred W Rademaker
- a Cognitive Neurology and Alzheimer's Disease Center , Northwestern University , Chicago , IL , USA.,b Department of Preventive Medicine , Northwestern University , Chicago , IL , USA
| | - Joel L Voss
- c Department of Medical Social Sciences , Northwestern University , Chicago , IL , USA
| | - Sandra Weintraub
- a Cognitive Neurology and Alzheimer's Disease Center , Northwestern University , Chicago , IL , USA
| | - Emily J Rogalski
- a Cognitive Neurology and Alzheimer's Disease Center , Northwestern University , Chicago , IL , USA
| | - Robert S Hurley
- a Cognitive Neurology and Alzheimer's Disease Center , Northwestern University , Chicago , IL , USA
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279
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Thompson HE, Robson H, Lambon Ralph MA, Jefferies E. Varieties of semantic 'access' deficit in Wernicke's aphasia and semantic aphasia. Brain 2015; 138:3776-92. [PMID: 26454668 PMCID: PMC4655340 DOI: 10.1093/brain/awv281] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Revised: 07/23/2015] [Accepted: 07/29/2015] [Indexed: 12/15/2022] Open
Abstract
Comprehension deficits are common in stroke aphasia, including in cases with (i) semantic aphasia, characterized by poor executive control of semantic processing across verbal and non-verbal modalities; and (ii) Wernicke's aphasia, associated with poor auditory-verbal comprehension and repetition, plus fluent speech with jargon. However, the varieties of these comprehension problems, and their underlying causes, are not well understood. Both patient groups exhibit some type of semantic 'access' deficit, as opposed to the 'storage' deficits observed in semantic dementia. Nevertheless, existing descriptions suggest that these patients might have different varieties of 'access' impairment-related to difficulty resolving competition (in semantic aphasia) versus initial activation of concepts from sensory inputs (in Wernicke's aphasia). We used a case series design to compare patients with Wernicke's aphasia and those with semantic aphasia on Warrington's paradigmatic assessment of semantic 'access' deficits. In these verbal and non-verbal matching tasks, a small set of semantically-related items are repeatedly presented over several cycles so that the target on one trial becomes a distractor on another (building up interference and eliciting semantic 'blocking' effects). Patients with Wernicke's aphasia and semantic aphasia were distinguished according to lesion location in the temporal cortex, but in each group, some individuals had additional prefrontal damage. Both of these aspects of lesion variability-one that mapped onto classical 'syndromes' and one that did not-predicted aspects of the semantic 'access' deficit. Both semantic aphasia and Wernicke's aphasia cases showed multimodal semantic impairment, although as expected, the Wernicke's aphasia group showed greater deficits on auditory-verbal than picture judgements. Distribution of damage in the temporal lobe was crucial for predicting the initially 'beneficial' effects of stimulus repetition: cases with Wernicke's aphasia showed initial improvement with repetition of words and pictures, while in semantic aphasia, semantic access was initially good but declined in the face of competition from previous targets. Prefrontal damage predicted the 'harmful' effects of repetition: the ability to reselect both word and picture targets in the face of mounting competition was linked to left prefrontal damage in both groups. Therefore, patients with semantic aphasia and Wernicke's aphasia have partially distinct impairment of semantic 'access' but, across these syndromes, prefrontal lesions produce declining comprehension with repetition in both verbal and non-verbal tasks.
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Affiliation(s)
- Hannah E Thompson
- 1 Department of Psychology and York Neuroimaging Centre, University of York, UK
| | - Holly Robson
- 2 School of Psychology and Clinical Language Sciences, University of Reading, UK
| | - Matthew A Lambon Ralph
- 3 Neuroscience and Aphasia Research Unit, School of Psychological Sciences, University of Manchester, UK
| | - Elizabeth Jefferies
- 1 Department of Psychology and York Neuroimaging Centre, University of York, UK
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Cahana-Amitay D, Spiro A, Sayers JT, Oveis AC, Higby E, Ojo EA, Duncan S, Goral M, Hyun J, Albert ML, Obler LK. How older adults use cognition in sentence-final word recognition. AGING NEUROPSYCHOLOGY AND COGNITION 2015; 23:418-44. [PMID: 26569553 DOI: 10.1080/13825585.2015.1111291] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
This study examined the effects of executive control and working memory on older adults' sentence-final word recognition. The question we addressed was the importance of executive functions to this process and how it is modulated by the predictability of the speech material. To this end, we tested 173 neurologically intact adult native English speakers aged 55-84 years. Participants were given a sentence-final word recognition test in which sentential context was manipulated and sentences were presented in different levels of babble, and multiple tests of executive functioning assessing inhibition, shifting, and efficient access to long-term memory, as well as working memory. Using a generalized linear mixed model, we found that better inhibition was associated with higher accuracy in word recognition, while increased age and greater hearing loss were associated with poorer performance. Findings are discussed in the framework of semantic control and are interpreted as supporting a theoretical view of executive control which emphasizes functional diversity among executive components.
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Affiliation(s)
- Dalia Cahana-Amitay
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA
| | - Avron Spiro
- b Department of Epidemiology , School of Public Health, Boston University , Boston , MA , USA.,c Department of Psychiatry , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA
| | - Jesse T Sayers
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA
| | - Abigail C Oveis
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA
| | - Eve Higby
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA.,e The Graduate Center, City University of New York , New York , NY , USA
| | - Emmanuel A Ojo
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA
| | - Susan Duncan
- e The Graduate Center, City University of New York , New York , NY , USA.,g Department of Cognitive Sciences and Neurology , University of California , Irvine , CA , USA
| | - Mira Goral
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA.,e The Graduate Center, City University of New York , New York , NY , USA.,f Lehman College, City University of New York , New York , NY , USA
| | - Jungmoon Hyun
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA.,e The Graduate Center, City University of New York , New York , NY , USA
| | - Martin L Albert
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA
| | - Loraine K Obler
- a Department of Neurology , Boston University School of Medicine , Boston , MA , USA.,d Veterans Affairs Boston Healthcare System , Boston , MA , USA.,e The Graduate Center, City University of New York , New York , NY , USA
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281
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Rice GE, Lambon Ralph MA, Hoffman P. The Roles of Left Versus Right Anterior Temporal Lobes in Conceptual Knowledge: An ALE Meta-analysis of 97 Functional Neuroimaging Studies. Cereb Cortex 2015; 25:4374-91. [PMID: 25771223 PMCID: PMC4816787 DOI: 10.1093/cercor/bhv024] [Citation(s) in RCA: 181] [Impact Index Per Article: 20.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
The roles of the right and left anterior temporal lobes (ATLs) in conceptual knowledge are a source of debate between 4 conflicting accounts. Possible ATL specializations include: (1) Processing of verbal versus non-verbal inputs; (2) the involvement of word retrieval; and (3) the social content of the stimuli. Conversely, the "hub-and-spoke" account holds that both ATLs form a bilateral functionally unified system. Using activation likelihood estimation (ALE) to compare the probability of left and right ATL activation, we analyzed 97 functional neuroimaging studies of conceptual knowledge, organized according to the predictions of the three specialized hypotheses. The primary result was that ATL activation was predominately bilateral and highly overlapping for all stimulus types. Secondary to this bilateral representation, there were subtle gradations both between and within the ATLs. Activations were more likely to be left lateralized when the input was a written word or when word retrieval was required. These data are best accommodated by a graded version of the hub-and-spoke account, whereby representation of conceptual knowledge is supported through bilateral yet graded connectivity between the ATLs and various modality-specific sensory, motor, and limbic cortices.
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Affiliation(s)
- Grace E Rice
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
| | - Matthew A Lambon Ralph
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
| | - Paul Hoffman
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
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282
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Lacombe J, Jolicoeur P, Grimault S, Pineault J, Joubert S. Neural changes associated with semantic processing in healthy aging despite intact behavioral performance. BRAIN AND LANGUAGE 2015; 149:118-127. [PMID: 26282079 DOI: 10.1016/j.bandl.2015.07.003] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Revised: 05/29/2015] [Accepted: 07/06/2015] [Indexed: 06/04/2023]
Abstract
Semantic memory recruits an extensive neural network including the left inferior prefrontal cortex (IPC) and the left temporoparietal region, which are involved in semantic control processes, as well as the anterior temporal lobe region (ATL) which is considered to be involved in processing semantic information at a central level. However, little is known about the underlying neuronal integrity of the semantic network in normal aging. Young and older healthy adults carried out a semantic judgment task while their cortical activity was recorded using magnetoencephalography (MEG). Despite equivalent behavioral performance, young adults activated the left IPC to a greater extent than older adults, while the latter group recruited the temporoparietal region bilaterally and the left ATL to a greater extent than younger adults. Results indicate that significant neuronal changes occur in normal aging, mainly in regions underlying semantic control processes, despite an apparent stability in performance at the behavioral level.
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Affiliation(s)
- Jacinthe Lacombe
- Département de psychologie, Université de Montréal, Pavillon Marie-Victorin, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; CERNEC, Université de Montréal, Pavillon Marie-Victorin, Département de psychologie, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; Centre de recherche de l'Institut universitaire de gériatrie de Montréal (CRIUGM), 4565 Chemin Queen-Mary, Montréal, Québec H3W 1W5, Canada.
| | - Pierre Jolicoeur
- Département de psychologie, Université de Montréal, Pavillon Marie-Victorin, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; CERNEC, Université de Montréal, Pavillon Marie-Victorin, Département de psychologie, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; Centre de recherche de l'Institut universitaire de gériatrie de Montréal (CRIUGM), 4565 Chemin Queen-Mary, Montréal, Québec H3W 1W5, Canada; International Laboratory for Brain, Music and Sound Research (BRAMS), Pavillon 1420 Mont-Royal, FAS - Département de psychologie, C.P. 6128, succ Centre-ville, Montréal, Québec H3C 3J7, Canada
| | - Stephan Grimault
- Département de psychologie, Université de Montréal, Pavillon Marie-Victorin, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; CERNEC, Université de Montréal, Pavillon Marie-Victorin, Département de psychologie, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; Centre national de la recherche scientifique (CNRS), 3 rue Michel-Ange 75794, Paris cedex 16, France
| | - Jessica Pineault
- Département de psychologie, Université de Montréal, Pavillon Marie-Victorin, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; CERNEC, Université de Montréal, Pavillon Marie-Victorin, Département de psychologie, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; Centre de recherche de l'Institut universitaire de gériatrie de Montréal (CRIUGM), 4565 Chemin Queen-Mary, Montréal, Québec H3W 1W5, Canada
| | - Sven Joubert
- Département de psychologie, Université de Montréal, Pavillon Marie-Victorin, C.P. 6128, succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada; Centre de recherche de l'Institut universitaire de gériatrie de Montréal (CRIUGM), 4565 Chemin Queen-Mary, Montréal, Québec H3W 1W5, Canada.
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283
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Shimotake A, Matsumoto R, Ueno T, Kunieda T, Saito S, Hoffman P, Kikuchi T, Fukuyama H, Miyamoto S, Takahashi R, Ikeda A, Lambon Ralph MA. Direct Exploration of the Role of the Ventral Anterior Temporal Lobe in Semantic Memory: Cortical Stimulation and Local Field Potential Evidence From Subdural Grid Electrodes. Cereb Cortex 2015; 25:3802-17. [PMID: 25491206 PMCID: PMC4585516 DOI: 10.1093/cercor/bhu262] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Semantic memory is a crucial higher cortical function that codes the meaning of objects and words, and when impaired after neurological damage, patients are left with significant disability. Investigations of semantic dementia have implicated the anterior temporal lobe (ATL) region, in general, as crucial for multimodal semantic memory. The potentially crucial role of the ventral ATL subregion has been emphasized by recent functional neuroimaging studies, but the necessity of this precise area has not been selectively tested. The implantation of subdural electrode grids over this subregion, for the presurgical assessment of patients with partial epilepsy or brain tumor, offers the dual yet rare opportunities to record cortical local field potentials while participants complete semantic tasks and to stimulate the functionally identified regions in the same participants to evaluate the necessity of these areas in semantic processing. Across 6 patients, and utilizing a variety of semantic assessments, we evaluated and confirmed that the anterior fusiform/inferior temporal gyrus is crucial in multimodal, receptive, and expressive, semantic processing.
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Affiliation(s)
| | - Riki Matsumoto
- Department of Epilepsy, Movement Disorders and Physiology
| | - Taiji Ueno
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
| | | | - Satoru Saito
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
- Department of Cognitive Psychology in Education, Graduate School of Education, Kyoto University, Kyoto, Japan
| | - Paul Hoffman
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
| | | | - Hidenao Fukuyama
- Human Brain Research Center, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | | | | | - Akio Ikeda
- Department of Epilepsy, Movement Disorders and Physiology
| | - Matthew A. Lambon Ralph
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, Manchester, UK
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284
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Chapados C, Petrides M. Ventrolateral and dorsomedial frontal cortex lesions impair mnemonic context retrieval. Proc Biol Sci 2015; 282:20142555. [PMID: 25567650 DOI: 10.1098/rspb.2014.2555] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The prefrontal cortex appears to contribute to the mnemonic retrieval of the context within which stimuli are experienced, but only under certain conditions that remain to be clarified. Patients with lesions to the frontal cortex, the temporal lobe and neurologically intact individuals were tested for context memory retrieval when verbal stimuli (words) had been experienced across multiple (unstable context condition) or unique (stable context condition) contexts; basic recognition memory of these words-in-contexts was also tested. Patients with lesions to the right ventrolateral prefrontal cortex (VLPFC) were impaired on context retrieval only when the words had been seen in multiple contexts, demonstrating that this prefrontal region is critical for active retrieval processing necessary to disambiguate memory items embedded across multiple contexts. Patients with lesions to the left dorsomedial prefrontal region were impaired on both context retrieval conditions, regardless of the stability of the stimulus-to-context associations. Conversely, prefrontal lesions sparing the ventrolateral and dorsomedial regions did not impair context retrieval. Only patients with temporal lobe excisions were impaired on basic recognition memory. The results demonstrate a basic contribution of the left dorsomedial frontal region to mnemonic context retrieval, with the VLPFC engaged, selectively, when contextual relations are unstable and require disambiguation.
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Affiliation(s)
- Catherine Chapados
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, 3801 University, Montreal, Quebec, Canada H3A 2B4 Department of Psychology, McGill University, 1205 Doctor Penfield Avenue, Montreal Quebec, Canada H3A 1B1
| | - Michael Petrides
- Cognitive Neuroscience Unit, Montreal Neurological Institute, McGill University, 3801 University, Montreal, Quebec, Canada H3A 2B4 Department of Psychology, McGill University, 1205 Doctor Penfield Avenue, Montreal Quebec, Canada H3A 1B1
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285
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Meier EL, Lo M, Kiran S. Understanding semantic and phonological processing deficits in adults with aphasia: Effects of category and typicality. APHASIOLOGY 2015; 30:719-749. [PMID: 27041784 PMCID: PMC4811611 DOI: 10.1080/02687038.2015.1081137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
BACKGROUND Semantic and phonological processing deficits are often present in aphasia. The degree of interdependence between the deficits has been widely studied with variable findings. Semantic variables such as category and typicality have been found to influence semantic processing in healthy individuals and persons with aphasia but their influence on phonological processing is unknown. AIMS This study examined the nature of semantic and phonological access in aphasia by comparing adults with aphasia to healthy control participants. Semantic and phonological tasks were used to assess the difference in processing requirements between and within each group as well as examine the effects of category and typicality on different stages of semantic and phonological processing. METHODS & PROCEDURES Thirty-two persons with aphasia and ten neurologically healthy adults were administered nine tasks: Category Superordinate, Category Coordinate, Semantic Feature, Rhyme Judgment (No-Name), Syllable Judgment (No-Name), Phoneme Verification (No-Name), Rhyme Judgment (Name-Provided), Syllable Judgment (Name-Provided), and Phoneme Verification (Name-Provided). Accuracy and reaction time data were collected for each of these tasks and between-group and within-group differences were analyzed via MANOVA/MANCOVA and hierarchical clustering analyses. OUTCOMES & RESULTS Persons with aphasia performed with significantly lower accuracy than controls on phonological tasks but performed comparably on semantic tasks. Participants with aphasia were significantly slower than controls on all semantic and phonological tasks. Clustering of the nine tasks by accuracy revealed different processing requirements in the participants with aphasia compared to the control group while clustering by reaction time revealed similar trends in both groups in that phonological (no-name) items required the most processing time. Significant effects of category and typicality were noted in the semantic tasks but not in any of the phonological tasks. CONCLUSIONS Individuals with aphasia demonstrated overall impaired phonological processing with relatively preserved semantic processing as compared to controls. Per accuracy and reaction time measures, distinct trends in processing load for semantic tasks versus phonological tasks were seen in the individuals with aphasia whereas only speed of processing and not accuracy was impacted by phonological processing load in the control group. The results align most closely with discrete serial processing models of lexical processing as category and typicality effects were robust in the semantic tasks but not in any of the phonological tasks. Alternative explanations for these results also are discussed.
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Affiliation(s)
- Erin L. Meier
- Aphasia Research Laboratory, Speech, Language & Hearing Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA, USA 02215, 617-353-2706
| | - Melody Lo
- South Shore Hospital, 55 Fogg Road, South Weymouth, MA, USA 02190
| | - Swathi Kiran
- Aphasia Research Laboratory, Speech, Language & Hearing Sciences, Boston University, 635 Commonwealth Avenue, Boston, MA, USA 02215, 617-358-5478
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286
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Rogers TT, Patterson K, Jefferies E, Ralph MAL. Disorders of representation and control in semantic cognition: Effects of familiarity, typicality, and specificity. Neuropsychologia 2015; 76:220-39. [PMID: 25934635 PMCID: PMC4582808 DOI: 10.1016/j.neuropsychologia.2015.04.015] [Citation(s) in RCA: 90] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Revised: 04/14/2015] [Accepted: 04/16/2015] [Indexed: 11/18/2022]
Abstract
We present a case-series comparison of patients with cross-modal semantic impairments consequent on either (a) bilateral anterior temporal lobe atrophy in semantic dementia (SD) or (b) left-hemisphere fronto-parietal and/or posterior temporal stroke in semantic aphasia (SA). Both groups were assessed on a new test battery designed to measure how performance is influenced by concept familiarity, typicality and specificity. In line with previous findings, performance in SD was strongly modulated by all of these factors, with better performance for more familiar items (regardless of typicality), for more typical items (regardless of familiarity) and for tasks that did not require very specific classification, consistent with the gradual degradation of conceptual knowledge in SD. The SA group showed significant impairments on all tasks but their sensitivity to familiarity, typicality and specificity was more variable and governed by task-specific effects of these factors on controlled semantic processing. The results are discussed with reference to theories about the complementary roles of representation and manipulation of semantic knowledge.
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Affiliation(s)
- Timothy T Rogers
- MRC Cognition & Brain Sciences Unit, Cambridge, UK; Department of Psychology, University of Wisconsin-Madison, USA.
| | - Karalyn Patterson
- MRC Cognition & Brain Sciences Unit, Cambridge, UK; Department of Clinical Neurosciences, University of Cambridge, UK
| | | | - Matthew A Lambon Ralph
- Neuroscience and Aphasia Research Unit, School of Psychological Sciences, University of Manchester, UK
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287
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Mirman D, Zhang Y, Wang Z, Coslett HB, Schwartz MF. The ins and outs of meaning: Behavioral and neuroanatomical dissociation of semantically-driven word retrieval and multimodal semantic recognition in aphasia. Neuropsychologia 2015; 76:208-19. [PMID: 25681739 PMCID: PMC4534364 DOI: 10.1016/j.neuropsychologia.2015.02.014] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 01/30/2015] [Accepted: 02/10/2015] [Indexed: 12/12/2022]
Abstract
Theories about the architecture of language processing differ with regard to whether verbal and nonverbal comprehension share a functional and neural substrate and how meaning extraction in comprehension relates to the ability to use meaning to drive verbal production. We (re-)evaluate data from 17 cognitive-linguistic performance measures of 99 participants with chronic aphasia using factor analysis to establish functional components and support vector regression-based lesion-symptom mapping to determine the neural correlates of deficits on these functional components. The results are highly consistent with our previous findings: production of semantic errors is behaviorally and neuroanatomically distinct from verbal and nonverbal comprehension. Semantic errors were most strongly associated with left ATL damage whereas deficits on tests of verbal and non-verbal semantic recognition were most strongly associated with damage to deep white matter underlying the frontal lobe at the confluence of multiple tracts, including the inferior fronto-occipital fasciculus, the uncinate fasciculus, and the anterior thalamic radiations. These results suggest that traditional views based on grey matter hub(s) for semantic processing are incomplete and that the role of white matter in semantic cognition has been underappreciated.
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Affiliation(s)
- Daniel Mirman
- Moss Rehabilitation Research Institute, 50 Township Line Rd., Elkins Park, PA 19027, USA; Department of Psychology, Drexel University, 3141 Chestnut St., Philadelphia, PA 19104, USA.
| | - Yongsheng Zhang
- University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA
| | - Ze Wang
- University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA
| | - H Branch Coslett
- University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104, USA
| | - Myrna F Schwartz
- Moss Rehabilitation Research Institute, 50 Township Line Rd., Elkins Park, PA 19027, USA.
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288
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Gotts SJ, Milleville SC, Martin A. Object identification leads to a conceptual broadening of object representations in lateral prefrontal cortex. Neuropsychologia 2015; 76:62-78. [PMID: 25445775 PMCID: PMC4424186 DOI: 10.1016/j.neuropsychologia.2014.10.041] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2014] [Revised: 10/16/2014] [Accepted: 10/28/2014] [Indexed: 11/28/2022]
Abstract
Recent experience identifying objects leads to later improvements in both speed and accuracy ("repetition priming"), along with simultaneous reductions of neural activity ("repetition suppression"). A popular interpretation of these joint behavioral and neural phenomena is that object representations become perceptually "sharper" with stimulus repetition, eliminating cells that are poorly stimulus-selective and responsive and reducing support for competing representations downstream. Here, we test this hypothesis in an fMRI-adaptation experiment using pictures of objects. Prior to fMRI, participants repeatedly named a set of object pictures. During fMRI, participants viewed adaptation sequences composed of rapidly repeated objects (3-6 repetitions over several seconds) that were either named previously or that were new for the fMRI session, followed by single "deviant" object pictures used to measure recovery from adaptation and that shared a relationship to the adapted picture (a different exemplar of the same object, a conceptual associate, or an unrelated picture). Effects of adaptation and recovery were found throughout visually responsive brain regions. Occipitotemporal cortical regions displayed repetition suppression to previously named relative to new adapters but failed to exhibit pronounced changes in neural tuning. In contrast, changes in the slope of the recovery curves were found in the left lateral prefrontal cortex: Greater residual adaptation was observed to exemplar stimuli and conceptual associates following previously named adapting stimuli, consistent with greater rather than reduced neural overlap among representations of conceptually related objects. Furthermore, this change in neural tuning was directly related to the proportion of conceptual errors made by participants in the naming sessions pre- and post-fMRI, establishing that the experience-dependent conceptual broadening of object representations seen in fMRI is also manifest in behavior. In a follow-up behavioral experiment, we further show that recent naming experience leads to greater semantic priming when using the previously named pictures as briefly presented primes. Taken together, our results fail to support perceptual sharpening as the primary mediator between repetition suppression and behavioral priming at durations typically used to study priming and instead highlight an experience-dependent broadening of conceptual representations. We suggest that alternative mechanisms, such as increases in neural synchronization, are more promising in explaining priming in the face of repetition suppression.
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Affiliation(s)
- Stephen J Gotts
- Section on Cognitive Neuropsychology, Laboratory of Brain, and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health, Bethesda, MD 20892, USA.
| | - Shawn C Milleville
- Section on Cognitive Neuropsychology, Laboratory of Brain, and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health, Bethesda, MD 20892, USA
| | - Alex Martin
- Section on Cognitive Neuropsychology, Laboratory of Brain, and Cognition, National Institute of Mental Health (NIMH), National Institutes of Health, Bethesda, MD 20892, USA
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289
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Binney RJ, Ralph MAL. Using a combination of fMRI and anterior temporal lobe rTMS to measure intrinsic and induced activation changes across the semantic cognition network. Neuropsychologia 2015; 76:170-81. [PMID: 25448851 PMCID: PMC4582802 DOI: 10.1016/j.neuropsychologia.2014.11.009] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 11/03/2014] [Accepted: 11/07/2014] [Indexed: 01/08/2023]
Abstract
By developing and applying a method which combines fMRI and rTMS to explore semantic cognition, we identified both intrinsic (related to automatic changes in task/stimulus-related processing) and induced (i.e., associated with the effect of TMS) activation changes in the core, functionally-coupled network elements. Low-frequency rTMS applied to the human anterior temporal lobe (ATL) induced: (a) a local suppression at the site of stimulation; (b) remote suppression in three other ipsilateral semantic regions; and (c) a compensatory up-regulation in the contralateral ATL. Further examination of activity over time revealed that the compensatory changes appear to be a modulation of intrinsic variations that occur within the unperturbed network. As well as providing insights into the dynamic collaboration between core regions, the ability to observe intrinsic and induced changes in vivo may provide an important opportunity to understand the key mechanisms that underpin recovery of function in neurological patient groups.
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Affiliation(s)
- Richard J Binney
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, UK; Eleanor M. Saffran Center for Cognitive Neuroscience, Temple University, Philadelphia, PA, USA
| | - Matthew A Lambon Ralph
- Neuroscience and Aphasia Research Unit (NARU), School of Psychological Sciences, University of Manchester, UK.
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290
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Patterson K, Kopelman MD, Woollams AM, Brownsett SL, Geranmayeh F, Wise RJ. Semantic memory: Which side are you on? Neuropsychologia 2015; 76:182-91. [DOI: 10.1016/j.neuropsychologia.2014.11.024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2014] [Revised: 11/10/2014] [Accepted: 11/20/2014] [Indexed: 01/08/2023]
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291
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Kintz S, Wright HH, Fergadiotis G. Semantic Knowledge Use in Discourse Produced by Individuals with Anomic Aphasia. APHASIOLOGY 2015; 30:1012-1025. [PMID: 27429506 PMCID: PMC4945119 DOI: 10.1080/02687038.2015.1081140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
BACKGROUND Researchers have demonstrated that people with aphasia (PWA) have preserved semantic knowledge (Dell et al., 1997; Jefferies & Lambon Ralph, 2006). However, Antonucci (2014) demonstrated that some PWA have impaired access to certain types of knowledge more than others. Yet, all these studies used single concepts. It has not been demonstrated whether PWA have difficulty accessing certain types of features within a discourse sample. AIMS The main goals of this study were to determine if semantic knowledge and two category types were used differently within discourse produced by participants with anomic aphasia and healthy controls. METHOD & PROCEDURES Participants with anomic aphasia (n=19) and healthy controls (n=19) told stories that were transcribed and coded for 10 types of semantic knowledge and two category types, living and nonliving things. OUTCOMES & RESULTS A Poisson regression model was conducted. The results indicated a significant difference between the groups for the semantic knowledge types, sound and internal state, but no difference was found for category types. Yet the distribution of semantic knowledge and category types produced within the discourse samples were similar between the groups. CONCLUSION PWA might have differential access to certain types of semantic knowledge within discourse production, but it does not rise to the level of categorical deficits. These findings extend single-concept research into the realm of discourse.
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292
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Lee SH, Booth JR, Chou TL. Developmental changes in the neural influence of sublexical information on semantic processing. Neuropsychologia 2015; 73:25-34. [DOI: 10.1016/j.neuropsychologia.2015.05.001] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2014] [Revised: 03/24/2015] [Accepted: 05/01/2015] [Indexed: 10/23/2022]
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293
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Jackson RL, Lambon Ralph MA, Pobric G. The Timing of Anterior Temporal Lobe Involvement in Semantic Processing. J Cogn Neurosci 2015; 27:1388-96. [DOI: 10.1162/jocn_a_00788] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Abstract
Despite indications that regions within the anterior temporal lobe (ATL) might make a crucial contribution to pan-modal semantic representation, to date there have been no investigations of when during semantic processing the ATL plays a critical role. To test the timing of the ATL involvement in semantic processing, we studied the effect of double-pulse TMS on behavioral responses in semantic and difficulty-matched control tasks. Chronometric TMS was delivered over the left ATL (10 mm from the tip of the temporal pole along the middle temporal gyrus). During each trial, two pulses of TMS (40 msec apart) were delivered either at baseline (before stimulus presentation) or at one of the experimental time points 100, 250, 400, and 800 msec poststimulus onset. A significant disruption to performance was identified from 400 msec on the semantic task but not on the control assessment. Our results not only reinforce the key role of the left ATL in semantic representation but also indicate that its contribution is especially important around 400 msec poststimulus onset. Together, these facts suggest that the ATL may be one of the neural sources of the N400 ERP component.
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294
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Mesulam MM, Thompson CK, Weintraub S, Rogalski EJ. The Wernicke conundrum and the anatomy of language comprehension in primary progressive aphasia. Brain 2015; 138:2423-37. [PMID: 26112340 DOI: 10.1093/brain/awv154] [Citation(s) in RCA: 138] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 04/14/2015] [Indexed: 11/14/2022] Open
Abstract
Wernicke's aphasia is characterized by severe word and sentence comprehension impairments. The location of the underlying lesion site, known as Wernicke's area, remains controversial. Questions related to this controversy were addressed in 72 patients with primary progressive aphasia who collectively displayed a wide spectrum of cortical atrophy sites and language impairment patterns. Clinico-anatomical correlations were explored at the individual and group levels. These analyses showed that neuronal loss in temporoparietal areas, traditionally included within Wernicke's area, leave single word comprehension intact and cause inconsistent impairments of sentence comprehension. The most severe sentence comprehension impairments were associated with a heterogeneous set of cortical atrophy sites variably encompassing temporoparietal components of Wernicke's area, Broca's area, and dorsal premotor cortex. Severe comprehension impairments for single words, on the other hand, were invariably associated with peak atrophy sites in the left temporal pole and adjacent anterior temporal cortex, a pattern of atrophy that left sentence comprehension intact. These results show that the neural substrates of word and sentence comprehension are dissociable and that a circumscribed cortical area equally critical for word and sentence comprehension is unlikely to exist anywhere in the cerebral cortex. Reports of combined word and sentence comprehension impairments in Wernicke's aphasia come almost exclusively from patients with cerebrovascular accidents where brain damage extends into subcortical white matter. The syndrome of Wernicke's aphasia is thus likely to reflect damage not only to the cerebral cortex but also to underlying axonal pathways, leading to strategic cortico-cortical disconnections within the language network. The results of this investigation further reinforce the conclusion that the left anterior temporal lobe, a region ignored by classic aphasiology, needs to be inserted into the language network with a critical role in the multisynaptic hierarchy underlying word comprehension and object naming.
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Affiliation(s)
- M-Marsel Mesulam
- 1 Cognitive Neurology and Alzheimer's Disease Centre, Northwestern University, Chicago, Illinois 60611, USA 2 Department of Neurology, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA 3 Department of Psychology, Northwestern University, Chicago, Illinois 60611, USA
| | - Cynthia K Thompson
- 1 Cognitive Neurology and Alzheimer's Disease Centre, Northwestern University, Chicago, Illinois 60611, USA 4 Department of Communication Sciences and Disorders, Northwestern University, Chicago, Illinois 60611, USA
| | - Sandra Weintraub
- 1 Cognitive Neurology and Alzheimer's Disease Centre, Northwestern University, Chicago, Illinois 60611, USA 5 Department of Psychiatry and Behavioral Sciences, Feinberg School of Medicine, Northwestern University, Chicago, Illinois 60611, USA
| | - Emily J Rogalski
- 1 Cognitive Neurology and Alzheimer's Disease Centre, Northwestern University, Chicago, Illinois 60611, USA
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295
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Mitchell MT. Semantic processing of English sentences using statistical computation based on neurophysiological models. Front Physiol 2015; 6:135. [PMID: 26106331 PMCID: PMC4460779 DOI: 10.3389/fphys.2015.00135] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2014] [Accepted: 04/15/2015] [Indexed: 11/23/2022] Open
Abstract
Computer programs that can accurately interpret natural human language and carry out instructions would improve the lives of people with language processing deficits and greatly benefit society in general. von Neumann in theorized that the human brain utilizes its own unique statistical neuronal computation to decode language and that this produces specific patterns of neuronal activity. This paper extends von Neumann's theory to the processing of partial semantics of declarative sentences. I developed semantic neuronal network models that emulate key features of cortical language processing and accurately compute partial semantics of English sentences. The method of computation implements the MAYA Semantic Technique, a mathematical technique I previously developed to determine partial semantics of sentences within a natural language processing program. Here I further simplified the technique by grouping repeating patterns into fewer categories. Unlike other natural language programs, my approach computes three partial semantics. The results of this research show that the computation of partial semantics of a sentence uses both feedforward and feedback projection which suggest that the partial semantic presented in this research might be a conscious activity within the human brain.
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Affiliation(s)
- Marcia T Mitchell
- Computer and Information Sciences Department, Saint Peter's University Jersey, NJ, USA
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296
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Different Temporal Patterns of Specific and General Autobiographical Memories across the Lifespan in Alzheimer's Disease. Behav Neurol 2015; 2015:963460. [PMID: 26175549 PMCID: PMC4484842 DOI: 10.1155/2015/963460] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 01/08/2015] [Accepted: 01/09/2015] [Indexed: 12/03/2022] Open
Abstract
We compared specific (i.e., associated with a unique time and space) and general (i.e., extended or repeated events) autobiographical memories (AbM) in Alzheimer's disease (AD). The comparison aims at investigating the relationship between these two components of AbM across the lifespan and the volume of cerebral regions of interest within the temporal lobe. We hypothesized that the ability to elicit specific memories would correlate with hippocampal volume, whereas evoking general memories would be related to lateral temporal lobe.
AbM was assessed using the modified Crovitz test in 18 patients with early AD and 18 matched controls. The proportions of total memories—supposed to reflect the ability to produce general memories—and specific memories retrieved were compared between AD patients and controls. Correlations to MRI volumes of temporal cortex were tested. We found different temporal patterns for specific and general memories in AD patients, with (i) relatively spared general memories, according to a temporal gradient that preserved remote memories, predominantly associated with right lateral temporal cortex volume. (ii) Conversely, the retrieval of specific AbMs was impaired for all life periods and correlated with bilateral hippocampal volumes. Our results highlight a shift from an initially episodic to a semantic nature of AbMs during AD, where the abstracted form of
memories remains.
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297
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Callahan BL, Joubert S, Tremblay MP, Macoir J, Belleville S, Rousseau F, Bouchard RW, Verret L, Hudon C. Semantic memory impairment for biological and man-made objects in individuals with amnestic mild cognitive impairment or late-life depression. J Geriatr Psychiatry Neurol 2015; 28:108-16. [PMID: 25344480 DOI: 10.1177/0891988714554708] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/10/2014] [Accepted: 06/10/2014] [Indexed: 11/17/2022]
Abstract
OBJECTIVE Amnestic mild cognitive impairment (aMCI) and late-life depression (LLD) both increase the risk of developing Alzheimer disease (AD). Very little is known about the similarities and differences between these syndromes. The present study addresses this issue by examining the nature of semantic memory impairment (more precisely, object-based knowledge) in patients at risk of developing AD. METHODS Participants were 17 elderly patients with aMCI, 18 patients with aMCI plus depressive symptoms (aMCI/D+), 15 patients with LLD, and 29 healthy controls. All participants were aged 55 years or older and were administered a semantic battery designed to assess semantic knowledge for 16 biological and 16 man-made items. RESULTS Overall performance of aMCI/D+ participants was significantly worse than the 3 other groups, and performance for questions assessing knowledge for biological items was poorer than for questions relating to man-made items. CONCLUSION This study is the first to show that aMCI/D+ is associated with object-based semantic memory impairment. These results support the view that semantic deficits in aMCI are associated with concomitant depressive symptoms. However, depressive symptoms alone do not account exclusively for semantic impairment, since patients with LLD showed no semantic memory deficit.
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Affiliation(s)
- Brandy L Callahan
- École de psychologie, Université Laval, Quebec, Canada Centre de recherche de l'Institut universitaire en santé mentale de Québec, Quebec, Canada
| | - Sven Joubert
- Département de psychologie, Université de Montréal, Montreal, Canada Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montreal, Canada
| | - Marie-Pier Tremblay
- École de psychologie, Université Laval, Quebec, Canada Centre de recherche de l'Institut universitaire en santé mentale de Québec, Quebec, Canada
| | - Joël Macoir
- Centre de recherche de l'Institut universitaire en santé mentale de Québec, Quebec, Canada Département de réadaptation, Université Laval, Quebec, Canada
| | - Sylvie Belleville
- Département de psychologie, Université de Montréal, Montreal, Canada Centre de recherche de l'Institut universitaire de gériatrie de Montréal, Montreal, Canada
| | | | - Rémi W Bouchard
- Clinique interdisciplinaire de la mémoire du CHU de Québec, Quebec, Canada
| | - Louis Verret
- Clinique interdisciplinaire de la mémoire du CHU de Québec, Quebec, Canada
| | - Carol Hudon
- École de psychologie, Université Laval, Quebec, Canada Centre de recherche de l'Institut universitaire en santé mentale de Québec, Quebec, Canada
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298
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Harvey DY, Schnur TT. Distinct loci of lexical and semantic access deficits in aphasia: Evidence from voxel-based lesion-symptom mapping and diffusion tensor imaging. Cortex 2015; 67:37-58. [DOI: 10.1016/j.cortex.2015.03.004] [Citation(s) in RCA: 73] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2013] [Revised: 08/14/2014] [Accepted: 03/09/2015] [Indexed: 11/16/2022]
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299
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Neuroscience of Aphasia Recovery: the Concept of Neural Multifunctionality. Curr Neurol Neurosci Rep 2015; 15:41. [DOI: 10.1007/s11910-015-0568-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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300
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Language as grist to the mill of cognition. Cogn Process 2015; 16:219-43. [PMID: 25976728 DOI: 10.1007/s10339-015-0656-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2014] [Accepted: 04/23/2015] [Indexed: 10/23/2022]
Abstract
There is a growing consensus that natural language plays a significant role in our cognitive lives. However, this role of language is not adequately characterised. In this paper, I investigate the relationship between natural language and thinking and argue that thinking operates largely according to associationistic rules. Furthermore, I show that language is neither restricted to interfacing between a 'Language of Thought' and the conscious level, nor is it constitutively involved in thinking. Unlike available alternatives, the suggested view predicts and accommodates a large battery of empirical evidence. Furthermore, it avoids problems that associationistic views traditionally faced, e.g. problems of propositional thinking and compositionality of thought.
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