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Tol S, de Haan GA, Postuma EMJL, Jansen JL, Heutink J. Reading Difficulties in Individuals with Homonymous Visual Field Defects: A Systematic Review of Reported Interventions. Neuropsychol Rev 2024:10.1007/s11065-024-09636-4. [PMID: 38639880 DOI: 10.1007/s11065-024-09636-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2023] [Accepted: 02/20/2024] [Indexed: 04/20/2024]
Abstract
Reading difficulties are amongst the most commonly reported problems in individuals with homonymous visual field defects (HVFDs). To be able to provide guidance for healthcare professionals considering offering reading training, researchers in this field and interested individuals with HVFDs, this systematic review aims to (1) provide an overview of the contextual and intervention characteristics of all published HVFD interventions and (2) generate insights into the different reading outcome measures that these studies adopted. A search on PsycINFO, MEDLINE and Web of Science was conducted up to February 2, 2023. All intervention studies for HVFD in which reading was measured were included. Data was collected about the intervention type, session duration, number of sessions, the intensity, duration, circumstance of the interventions, country in which the intervention was studied and reading measures. Sixty records are included, describing 70 interventions in total of which 21 are specifically reading interventions. Overall, adjusted saccadic behaviour interventions occur most in the literature. A wide range within all intervention characteristics was observed. Forty-nine records reported task-performance reading measures, and 33 records reported self-reported reading measures. The majority of task-performance measures are based on self-developed paragraph reading tasks with a time-based outcome measure (e.g. words per minute). Future research could benefit from making use of validated reading tests, approaching the measurement of reading mixed-methods and providing participants the possibility to supply outcomes relevant to them.
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Affiliation(s)
- S Tol
- Clinical and Developmental Neuropsychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS, Groningen, The Netherlands.
| | - G A de Haan
- Clinical and Developmental Neuropsychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS, Groningen, The Netherlands
- Royal Dutch Visio, Centre of Expertise for Blind and Partially Sighted People, Amersfoortsestraatweg 180, 1272 RR, Huizen, The Netherlands
| | - E M J L Postuma
- Clinical and Developmental Neuropsychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS, Groningen, The Netherlands
| | - J L Jansen
- Clinical and Developmental Neuropsychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS, Groningen, The Netherlands
| | - J Heutink
- Clinical and Developmental Neuropsychology, University of Groningen, Grote Kruisstraat 2/1, 9712 TS, Groningen, The Netherlands
- Royal Dutch Visio, Centre of Expertise for Blind and Partially Sighted People, Amersfoortsestraatweg 180, 1272 RR, Huizen, The Netherlands
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2
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Abstract
This chapter is written for the qualified neurologist or related professional working with persons who have had a stroke or other sudden brain injury. It is critical that the presence of aphasia is detected, no matter how mild the presentation, and to support that assertion, this chapter highlights the plight of persons with latent aphasia. At the individual level, the impact of aphasia is devastating, with overwhelming evidence that aphasia negatively impacts psychosocial outcomes. At the global level, sensitive detection and accurate diagnosis of aphasia are critical for accurate characterization and quantification of the global burden of aphasia. The word "LANGUAGE" is leveraged as an acronym to create a useful and memorable checklist to guide navigation of aphasia screening and assessment: it begins with the definition of language (L), followed by the definition and diagnostic criteria for aphasia (A). Then language abilities and characteristics to be considered in assessment are presented: naming (N); grammar and syntax (G); unintelligible words, jargon, and paraphasias (U); auditory comprehension and repetition (A); graphemic abilities-reading and writing (G); and everyday communication and discourse (E). Recommendations for improving procedural adherence are provided, and a list of potential brief assessment measures are introduced.
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Affiliation(s)
- Jessica D Richardson
- Department of Speech and Hearing Sciences, University of New Mexico, Albuquerque, NM, United States.
| | - Sarah Grace Dalton
- Department of Speech Pathology and Audiology, Marquette University, Milwaukee, WI, United States
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3
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Kocagoncu E, Klimovich-Gray A, Hughes LE, Rowe JB. Evidence and implications of abnormal predictive coding in dementia. Brain 2021; 144:3311-3321. [PMID: 34240109 PMCID: PMC8677549 DOI: 10.1093/brain/awab254] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 03/15/2021] [Accepted: 06/17/2021] [Indexed: 11/14/2022] Open
Abstract
The diversity of cognitive deficits and neuropathological processes associated with dementias has encouraged divergence in pathophysiological explanations of disease. Here, we review an alternative framework that emphasizes convergent critical features of cognitive pathophysiology. Rather than the loss of ‘memory centres’ or ‘language centres’, or singular neurotransmitter systems, cognitive deficits are interpreted in terms of aberrant predictive coding in hierarchical neural networks. This builds on advances in normative accounts of brain function, specifically the Bayesian integration of beliefs and sensory evidence in which hierarchical predictions and prediction errors underlie memory, perception, speech and behaviour. We describe how analogous impairments in predictive coding in parallel neurocognitive systems can generate diverse clinical phenomena, including the characteristics of dementias. The review presents evidence from behavioural and neurophysiological studies of perception, language, memory and decision-making. The reformulation of cognitive deficits in terms of predictive coding has several advantages. It brings diverse clinical phenomena into a common framework; it aligns cognitive and movement disorders; and it makes specific predictions on cognitive physiology that support translational and experimental medicine studies. The insights into complex human cognitive disorders from the predictive coding framework may therefore also inform future therapeutic strategies.
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Affiliation(s)
- Ece Kocagoncu
- Cambridge Centre for Frontotemporal Dementia, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK
| | | | - Laura E Hughes
- Cambridge Centre for Frontotemporal Dementia, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
| | - James B Rowe
- Cambridge Centre for Frontotemporal Dementia, Department of Clinical Neurosciences, University of Cambridge, Cambridge, UK.,Medical Research Council Cognition and Brain Sciences Unit, University of Cambridge, Cambridge, UK
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4
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Rehabilitation of visual disorders. HANDBOOK OF CLINICAL NEUROLOGY 2021; 178:361-386. [PMID: 33832686 DOI: 10.1016/b978-0-12-821377-3.00015-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
While there is a long history of rehabilitation for motor deficits following cerebral lesions, less is known about our ability to improve visual deficits. Vision therapy, prisms, occluders, and filters have been advocated for patients with mild traumatic brain injury, on the premise that some of their symptoms may reflect abnormal visual or ocular motor function, but the evidence for their efficacy is modest. For hemianopia, attempts to restore vision have had unimpressive results, though it appears possible to generate blindsight through training. Strategic approaches that train more efficient use of visual search in hemianopia have shown consistent benefit in visual function, while prism aids may help some patients. There are many varieties of alexia. Strategic adaptation of saccades can improve hemianopic alexia, but there has been less work and mixed results for pure alexia, neglect dyslexia, attentional dyslexia, and the central dyslexias. A number of approaches have been tried in prosopagnosia, with recent studies of small groups suggesting that face perception of prosopagnosic subjects can be enhanced through perceptual learning.
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Tak S, Lee S, Park CA, Cheong EN, Seok JW, Sohn JH, Cheong C. Altered Effective Connectivity within the Fronto-Limbic Circuitry in Response to Negative Emotional Task in Female Patients with Major Depressive Disorder. Brain Connect 2021; 11:264-277. [PMID: 33403894 DOI: 10.1089/brain.2020.0859] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Background: Major depressive disorder (MDD) is a mood disorder associated with disruptions in emotional control. Previous studies have investigated abnormal regional activity and connectivity within the fronto-limbic circuit. However, condition-specific connectivity changes and their association with the pathophysiology of MDD remain unexplored. This study investigated effective connectivity in the fronto-limbic circuit induced by negative emotional processing from patients with MDD. Methods: Thirty-four unmedicated female patients with MDD and 28 healthy participants underwent event-related functional magnetic resonance imaging at 7T while viewing emotionally negative and neutral images. Brain regions whose dynamics are driven by experimental conditions were identified by using statistical parametric mapping. Effective connectivity among regions of interest was then estimated by using dynamic causal modeling. Results: Patients with MDD had lower activation of the orbitofrontal cortex (OFC) and higher activation of the parahippocampal gyrus (PHG) than healthy controls (HC). In association with these regional changes, we found that patients with MDD did not have significant modulatory connections from the primary visual cortex (V1) to OFC, whereas those connections of HC were significantly positively modulated during negative emotional processing. Regarding the PHG activity, patients with MDD had greater modulatory connection from the V1, but reduced negative modulatory connection from the OFC, compared with healthy participants. Conclusions: These results imply that disrupted effective connectivity among regions of the OFC, PHG, and V1 may be closely associated with the impaired regulation of negative emotional processing in the female patients with MDD.
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Affiliation(s)
- Sungho Tak
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Cheongju, Republic of Korea.,Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, Republic of Korea
| | - Seonjin Lee
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute, Cheongju, Republic of Korea.,Graduate School of Analytical Science and Technology, Chungnam National University, Daejeon, Republic of Korea
| | - Chan-A Park
- Bio-Chemical Analysis Team, Korea Basic Science Institute, Cheongju, Republic of Korea
| | - E-Nae Cheong
- Bio-Chemical Analysis Team, Korea Basic Science Institute, Cheongju, Republic of Korea
| | - Ji-Woo Seok
- Bio-Chemical Analysis Team, Korea Basic Science Institute, Cheongju, Republic of Korea
| | - Jin-Hun Sohn
- Department of Psychology, Chungnam National University, Daejeon, Republic of Korea
| | - Chaejoon Cheong
- Bio-Chemical Analysis Team, Korea Basic Science Institute, Cheongju, Republic of Korea
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Abstract
Alexia refers to a reading disorder caused by some form of acquired brain pathology, most commonly a stroke or tumor, in a previously literate subject. In neuropsychology, a distinction is made between central alexia (commonly seen in aphasia) and peripheral alexia (a perceptual or attentional deficit). The prototypical peripheral alexia is alexia without agraphia (pure alexia), where patients can write but are impaired in reading words and letters. Pure alexia is associated with damage to the left ventral occipitotemporal cortex (vOT) or its connections. Hemianopic alexia is associated with less extensive occipital damage and is caused by a visual field defect, which creates problems reading longer words and passages of text. Reading impairment can also arise due to attentional deficits, most commonly following right hemisphere or bilateral lesions. Studying patients with alexia, along with functional imaging studies of normal readers, has improved our understanding of the neurobiological processes involved in reading. A key question is whether an area in the left ventral occipitotemporal cortex is specialized for or selectively involved in word processing, or whether reading relies on tuning of more general purpose perceptual areas. Reading deficits may also be observed in dementia and traumatic brain injury, but often with less consistent deficit patterns than in patients with focal lesions.
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Affiliation(s)
- Randi Starrfelt
- Department of Psychology, University of Copenhagen, Copenhagen, Denmark.
| | - Zoe Woodhead
- Department of Experimental Psychology, University of Oxford, Oxford, United Kingdom
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Liu X, Vermeylen L, Wisniewski D, Brysbaert M. The contribution of phonological information to visual word recognition: Evidence from Chinese phonetic radicals. Cortex 2020; 133:48-64. [PMID: 33099075 DOI: 10.1016/j.cortex.2020.09.010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2020] [Revised: 07/09/2020] [Accepted: 09/17/2020] [Indexed: 11/28/2022]
Abstract
Lateralization is a critical characteristic of language production and also plays a role in visual word recognition. However, the neural mechanisms underlying the interactions between visual input and spoken word representations are still unclear. We investigated the contribution of sub-lexical phonological information in visual word processing by exploiting the fact that Chinese characters can contain phonetic radicals in either the left or right half of the character. FMRI data were collected while 39 Chinese participants read words in search of target color words. On the basis of whole-brain analysis and three laterality analyses of regions of interest, we argue that visual information from centrally presented Chinese characters is split in the fovea and projected to the contralateral visual cortex, from which phonological information can be extracted rapidly if the character contains a phonetic radical. Extra activation, suggestive of more effortful processing, is observed when the phonetic radical is situated in the left half of the character and therefore initially sent to the visual cortex in the right hemisphere that is less specialized for language processing. Our results are in line with the proposal that phonological information helps written word processing by means of top-down feedback.
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Affiliation(s)
- Xiaodong Liu
- Department of Experimental Psychology, Ghent University, Belgium.
| | - Luc Vermeylen
- Department of Experimental Psychology, Ghent University, Belgium
| | - David Wisniewski
- Department of Experimental Psychology, Ghent University, Belgium
| | - Marc Brysbaert
- Department of Experimental Psychology, Ghent University, Belgium
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8
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Dricu M, Frühholz S. A neurocognitive model of perceptual decision-making on emotional signals. Hum Brain Mapp 2020; 41:1532-1556. [PMID: 31868310 PMCID: PMC7267943 DOI: 10.1002/hbm.24893] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2019] [Revised: 11/18/2019] [Accepted: 11/29/2019] [Indexed: 01/09/2023] Open
Abstract
Humans make various kinds of decisions about which emotions they perceive from others. Although it might seem like a split-second phenomenon, deliberating over which emotions we perceive unfolds across several stages of decisional processing. Neurocognitive models of general perception postulate that our brain first extracts sensory information about the world then integrates these data into a percept and lastly interprets it. The aim of the present study was to build an evidence-based neurocognitive model of perceptual decision-making on others' emotions. We conducted a series of meta-analyses of neuroimaging data spanning 30 years on the explicit evaluations of others' emotional expressions. We find that emotion perception is rather an umbrella term for various perception paradigms, each with distinct neural structures that underline task-related cognitive demands. Furthermore, the left amygdala was responsive across all classes of decisional paradigms, regardless of task-related demands. Based on these observations, we propose a neurocognitive model that outlines the information flow in the brain needed for a successful evaluation of and decisions on other individuals' emotions. HIGHLIGHTS: Emotion classification involves heterogeneous perception and decision-making tasks Decision-making processes on emotions rarely covered by existing emotions theories We propose an evidence-based neuro-cognitive model of decision-making on emotions Bilateral brain processes for nonverbal decisions, left brain processes for verbal decisions Left amygdala involved in any kind of decision on emotions.
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Affiliation(s)
- Mihai Dricu
- Department of PsychologyUniversity of BernBernSwitzerland
| | - Sascha Frühholz
- Cognitive and Affective Neuroscience Unit, Department of PsychologyUniversity of ZurichZurichSwitzerland
- Neuroscience Center Zurich (ZNZ)University of Zurich and ETH ZurichZurichSwitzerland
- Center for Integrative Human Physiology (ZIHP)University of ZurichZurichSwitzerland
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9
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Characterising neural plasticity at the single patient level using connectivity fingerprints. NEUROIMAGE-CLINICAL 2019; 24:101952. [PMID: 31357148 PMCID: PMC6664196 DOI: 10.1016/j.nicl.2019.101952] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 07/11/2019] [Accepted: 07/19/2019] [Indexed: 02/07/2023]
Abstract
The occurrence of wide-scale neuroplasticity in the injured human brain raises hopes for biomarkers to guide personalised treatment. At the individual level, functional reorganisation has proven challenging to quantify using current techniques that are optimised for population-based analyses. In this cross-sectional study, we acquired functional MRI scans in 44 patients (22 men, 22 women, mean age: 39.4 ± 14 years) with a language-dominant hemisphere brain tumour prior to surgery and 23 healthy volunteers (11 men, 12 women, mean age: 36.3 ± 10.9 years) during performance of a verbal fluency task. We applied a recently developed approach to characterise the normal range of functional connectivity patterns during task performance in healthy controls. Next, we statistically quantified differences from the normal in individual patients and evaluated factors driving these differences. We show that the functional connectivity of brain regions involved in language fluency identifies “fingerprints” of brain plasticity in individual patients, not detected using standard task-evoked analyses. In contrast to healthy controls, patients with a tumour in their language dominant hemisphere showed highly variable fingerprints that uniquely distinguished individuals. Atypical fingerprints were influenced by tumour grade and tumour location relative to the typical fluency-activated network. Our findings show how alterations in brain networks can be visualised and statistically quantified from connectivity fingerprints in individual brains. We propose that connectivity fingerprints offer a statistical metric of individually-specific network organisation through which behaviourally-relevant adaptations could be formally quantified and monitored across individuals, treatments and time. Personalised treatment awaits individualised measures of brain adaptation. Connectivity patterns from FMRI offer unique “fingerprints” of brain networks. Individual brain tumours disrupt the language fluency network in unique ways. By fingerprint matching, networks can be tested and visualised in single patients.
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10
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Woodhead ZVJ, Kerry SJ, Aguilar OM, Ong YH, Hogan JS, Pappa K, Leff AP, Crinion JT. Randomized trial of iReadMore word reading training and brain stimulation in central alexia. Brain 2019; 141:2127-2141. [PMID: 29912350 PMCID: PMC6118228 DOI: 10.1093/brain/awy138] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2017] [Accepted: 04/03/2018] [Indexed: 11/16/2022] Open
Abstract
Central alexia is an acquired reading disorder co-occurring with a generalized language deficit (aphasia). We tested the impact of a novel training app, ‘iReadMore’, and anodal transcranial direct current stimulation of the left inferior frontal gyrus, on word reading ability in central alexia. The trial was registered at www.clinicaltrials.gov (NCT02062619). Twenty-one chronic stroke patients with central alexia participated. A baseline-controlled, repeated-measures, crossover design was used. Participants completed two 4-week blocks of iReadMore training, one with anodal stimulation and one with sham stimulation (order counterbalanced between participants). Each block comprised 34 h of iReadMore training and 11 stimulation sessions. Outcome measures were assessed before, between and after the two blocks. The primary outcome measures were reading ability for trained and untrained words. Secondary outcome measures included semantic word matching, sentence reading, text reading and a self-report measure. iReadMore training resulted in an 8.7% improvement in reading accuracy for trained words (95% confidence interval 6.0 to 11.4; Cohen’s d = 1.38) but did not generalize to untrained words. Reaction times also improved. Reading accuracy gains were still significant (but reduced) 3 months after training cessation. Anodal transcranial direct current stimulation (compared to sham), delivered concurrently with iReadMore, resulted in a 2.6% (95% confidence interval −0.1 to 5.3; d = 0.41) facilitation for reading accuracy, both for trained and untrained words. iReadMore also improved performance on the semantic word-matching test. There was a non-significant trend towards improved self-reported reading ability. However, no significant changes were seen at the sentence or text reading level. In summary, iReadMore training in post-stroke central alexia improved reading ability for trained words, with good maintenance of the therapy effect. Anodal stimulation resulted in a small facilitation (d = 0.41) of learning and also generalized to untrained items.
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Affiliation(s)
- Zoe V J Woodhead
- Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, UK.,Department of Experimental Psychology, University of Oxford, UK
| | - Sheila J Kerry
- Institute of Cognitive Neuroscience, University College London, UK
| | - Oscar M Aguilar
- Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, UK.,Wellcome Trust Centre for Neuroimaging, University College London, UK.,Facultad de Psicología, Pontificia Universidad Javeriana, Colombia
| | - Yean-Hoon Ong
- Wellcome Trust Centre for Neuroimaging, University College London, UK
| | - John S Hogan
- Experimental Psychology, University College London, UK
| | - Katerina Pappa
- Institute of Cognitive Neuroscience, University College London, UK
| | - Alex P Leff
- Department of Brain Repair and Rehabilitation, Institute of Neurology, University College London, UK.,Institute of Cognitive Neuroscience, University College London, UK.,Wellcome Trust Centre for Neuroimaging, University College London, UK
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11
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How Does iReadMore Therapy Change the Reading Network of Patients with Central Alexia? J Neurosci 2019; 39:5719-5727. [PMID: 31085605 DOI: 10.1523/jneurosci.1426-18.2019] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2018] [Revised: 03/07/2019] [Accepted: 03/16/2019] [Indexed: 11/21/2022] Open
Abstract
Central alexia (CA) is an acquired reading disorder co-occurring with a generalized language deficit (aphasia). The roles of perilesional and ipsilesional tissue in recovery from poststroke aphasia are unclear. We investigated the impact of reading training (using iReadMore, a therapy app) on the connections within and between the right and left hemisphere of the reading network of patients with CA. In patients with pure alexia, iReadMore increased feedback from left inferior frontal gyrus (IFG) region to the left occipital (OCC) region. We aimed to identify whether iReadMore therapy was effective through a similar mechanism in patients with CA. Participants with chronic poststroke CA (n = 23) completed 35 h of iReadMore training over 4 weeks. Reading accuracy for trained and untrained words was assessed before and after therapy. The neural response to reading trained and untrained words in the left and right OCC, ventral occipitotemporal, and IFG regions was examined using event-related magnetoencephalography. The training-related modulation in effective connectivity between regions was modeled at the group level with dynamic causal modeling. iReadMore training improved participants' reading accuracy by an average of 8.4% (range, -2.77 to 31.66) while accuracy for untrained words was stable. Training increased regional sensitivity in bilateral frontal and occipital regions, and strengthened feedforward connections within the left hemisphere. Our data suggest that iReadMore training in these patients modulates lower-order visual representations, as opposed to higher-order, more abstract representations, to improve word-reading accuracy.SIGNIFICANCE STATEMENT This is the first study to conduct a network-level analysis of therapy effects in participants with poststroke central alexia. When patients trained with iReadMore (a multimodal, behavioral, mass practice, computer-based therapy), reading accuracy improved by an average 8.4% on trained items. A network analysis of the magnetoencephalography data associated with this improvement revealed an increase in regional sensitivity in bilateral frontal and occipital regions and strengthening of feedforward connections within the left hemisphere. This indicates that in patients with CA iReadMore engages lower-order, intact resources within the left hemisphere (posterior to their lesion locations) to improve word reading. This provides a foundation for future research to investigate reading network modulation in different CA subtypes, or for sentence-level therapy.
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12
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Visual and kinesthetic modes affect motor imagery classification in untrained subjects. Sci Rep 2019; 9:9838. [PMID: 31285468 PMCID: PMC6614413 DOI: 10.1038/s41598-019-46310-9] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 06/21/2019] [Indexed: 11/20/2022] Open
Abstract
The understanding of neurophysiological mechanisms responsible for motor imagery (MI) is essential for the development of brain-computer interfaces (BCI) and bioprosthetics. Our magnetoencephalographic (MEG) experiments with voluntary participants confirm the existence of two types of motor imagery, kinesthetic imagery (KI) and visual imagery (VI), distinguished by activation and inhibition of different brain areas in motor-related α- and β-frequency regions. Although the brain activity corresponding to MI is usually observed in specially trained subjects or athletes, we show that it is also possible to identify particular features of MI in untrained subjects. Similar to real movement, KI implies muscular sensation when performing an imaginary moving action that leads to event-related desynchronization (ERD) of motor-associated brain rhythms. By contrast, VI refers to visualization of the corresponding action that results in event-related synchronization (ERS) of α- and β-wave activity. A notable difference between KI and VI groups occurs in the frontal brain area. In particular, the analysis of evoked responses shows that in all KI subjects the activity in the frontal cortex is suppressed during MI, while in the VI subjects the frontal cortex is always active. The accuracy in classification of left-arm and right-arm MI using artificial intelligence is similar for KI and VI. Since untrained subjects usually demonstrate the VI imagery mode, the possibility to increase the accuracy for VI is in demand for BCIs. The application of artificial neural networks allows us to classify MI in raising right and left arms with average accuracy of 70% for both KI and VI using appropriate filtration of input signals. The same average accuracy is achieved by optimizing MEG channels and reducing their number to only 13.
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13
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Aguilar OM, Kerry SJ, Ong YH, Callaghan MF, Crinion J, Woodhead ZVJ, Price CJ, Leff AP, Hope TMH. Lesion-site-dependent responses to therapy after aphasic stroke. J Neurol Neurosurg Psychiatry 2018; 89:1352-1354. [PMID: 29666209 PMCID: PMC6288693 DOI: 10.1136/jnnp-2017-317446] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Revised: 02/15/2018] [Accepted: 02/26/2018] [Indexed: 11/03/2022]
Affiliation(s)
- Oscar M Aguilar
- Department of Brain Repair and Rehabilitation, University College London, London, UK.,Wellcome Centre for Human Neuroimaging, University College London, London, UK.,Facultad de Psicologia, Pontificia Universidad Javeriana, Bogota, Colombia
| | - Sheila J Kerry
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Yean-Hoon Ong
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
| | - Martina F Callaghan
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
| | - Jennifer Crinion
- Institute of Cognitive Neuroscience, University College London, London, UK
| | - Zoe Victoria Joan Woodhead
- Department of Brain Repair and Rehabilitation, University College London, London, UK.,Wellcome Centre for Human Neuroimaging, University College London, London, UK.,Department of Experimental Psychology, University of Oxford, Oxford, UK
| | - Cathy J Price
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
| | - Alexander P Leff
- Department of Brain Repair and Rehabilitation, University College London, London, UK.,Wellcome Centre for Human Neuroimaging, University College London, London, UK.,Institute of Cognitive Neuroscience, University College London, London, UK
| | - Thomas M H Hope
- Wellcome Centre for Human Neuroimaging, University College London, London, UK
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14
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Gu H, Hou F, Liu L, Luo X, Nkomola PD, Xie X, Li X, Song R. Genetic variants in the CNTNAP2 gene are associated with gender differences among dyslexic children in China. EBioMedicine 2018; 34:165-170. [PMID: 30017804 PMCID: PMC6116347 DOI: 10.1016/j.ebiom.2018.07.007] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Revised: 07/06/2018] [Accepted: 07/06/2018] [Indexed: 01/03/2023] Open
Abstract
Background It is well known that males have a higher prevalence of developmental dyslexia (DD) than females. Although the mechanism underlying this gender difference remains unknown, the contactin-associated protein-like 2 (CNTNAP2) gene, which shows sex-specific patterns in some neurodevelopmental disorders, has attracted extensive attention. This study aimed to explore whether CNTNAP2 shows a sex-specific association with DD in a Chinese population. Methods Using genomic DNA samples of 726 students [372 cases (282 male, 90 female), 354 controls (267 male, 87 female)], we genotyped five SNPs of CNTNAP2. Gender-stratified logistic regression models were used to determine the relationships between the CNTNAP2 variants and DD. Findings After adjustment for the false discovery rate (FDR), two SNPs (rs3779031, rs987456) of CNTNAP2 were associated with DD risk in females but not in males. Female participants carrying the rs3779031 G allele had a lower risk of DD than those with the A genotype [GG vs AA: OR (95%CI) = 0.281 (0.097–0.814)]. The rs987456 CC genotype was associated with a decreased risk of DD in females [CC vs AA+CA: OR (95%CI) = 0.222 (0.078–0.628)]. Furthermore, the interaction between CNTNAP2 (rs987456) and environmental factors (scheduled reading time) played a protective role in females [OR (95%CI) = 0.431 (0.188–0.987)]. Interpretation We performed a genetic association study on CNTNAP2 variants and DD. The sex specificity of CNTNAP2 in DD, along with the gene-environment interaction may help us to understand gender differences in DD.
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Affiliation(s)
- Huaiting Gu
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Fang Hou
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Lingfei Liu
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Xiu Luo
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Pauline Denis Nkomola
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Xinyan Xie
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Xin Li
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China
| | - Ranran Song
- Department of Maternal and Child Health, MOE (Ministry of Education) Key Laboratory of Environment and Health, School of Public Health, Tongji Medical College, Huazhong University of Science and Technology, China.
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15
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Penny W, Iglesias-Fuster J, Quiroz YT, Lopera FJ, Bobes MA. Dynamic Causal Modeling of Preclinical Autosomal-Dominant Alzheimer's Disease. J Alzheimers Dis 2018; 65:697-711. [PMID: 29562504 PMCID: PMC6923812 DOI: 10.3233/jad-170405] [Citation(s) in RCA: 12] [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] [Accepted: 11/06/2017] [Indexed: 01/13/2023]
Abstract
Dynamic causal modeling (DCM) is a framework for making inferences about changes in brain connectivity using neuroimaging data. We fitted DCMs to high-density EEG data from subjects performing a semantic picture matching task. The subjects are carriers of the PSEN1 mutation, which leads to early onset Alzheimer's disease, but at the time of EEG acquisition in 1999, these subjects were cognitively unimpaired. We asked 1) what is the optimal model architecture for explaining the event-related potentials in this population, 2) which connections are different between this Presymptomatic Carrier (PreC) group and a Non-Carrier (NonC) group performing the same task, and 3) which network connections are predictive of subsequent Mini-Mental State Exam (MMSE) trajectories. We found 1) a model with hierarchical rather than lateral connections between hemispheres to be optimal, 2) that a pathway from right inferotemporal cortex (IT) to left medial temporal lobe (MTL) was preferentially activated by incongruent items for subjects in the PreC group but not the NonC group, and 3) that increased effective connectivity among left MTL, right IT, and right MTL was predictive of subsequent MMSE scores.
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Affiliation(s)
- Will Penny
- School of Psychology, University of East Anglia, Norwich, UK
- Wellcome Trust Centre for Neuroimaging, University College, London, UK
| | | | - Yakeel T. Quiroz
- Massachusetts General Hospital, Boston, MA, USA
- Group of Neurosciences, Medical School, Universidad de Antioquia, Medellin, Colombia
| | | | - Maria A. Bobes
- Department of Cognitive Neuroscience Cuban Neuroscience Center, Havana, Cuba
- Key Laboratory for Neuroinformation of Ministry of Education, Center for Information in Medicine, University of Electronic Science and Technology of China
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16
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Hanna KL, Rowe FJ. Clinical versus Evidence-based Rehabilitation Options for Post-stroke Visual Impairment. Neuroophthalmology 2017; 41:297-305. [PMID: 29344068 PMCID: PMC5764068 DOI: 10.1080/01658107.2017.1337159] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2017] [Revised: 05/22/2017] [Accepted: 05/29/2017] [Indexed: 10/19/2022] Open
Abstract
The aim of this study was to identify which treatments for post-stroke visual impairment have a supportive evidence base, and which are being used in practice without supportive evidence. A systematic review of the literature reporting on the available treatment options was compared against the visual treatments used in the Vision In Stroke (VIS) study. Treatments were identified for visual field, visual neglect, visual perception and ocular motility disorders. Visual scanning therapies for hemianopia and neglect have an established evidence base. However, a number, such as typoscopes and advice options, have limited detail of their effectiveness and require further research.
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Affiliation(s)
- K. L. Hanna
- Department of Health Services Research, University of Liverpool, Liverpool, United Kingdom
| | - F. J. Rowe
- Department of Health Services Research, University of Liverpool, Liverpool, United Kingdom
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17
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Abstract
A longstanding controversy concerns the functional organization of high-level vision, and the extent to which the recognition of different classes of visual stimuli engages a single system or multiple independent systems. We examine this in the context of congenital prosopagnosia (CP), a neurodevelopmental disorder in which individuals, without a history of brain damage, are impaired at face recognition. This paper reviews all CP cases from 1976 to 2016, and explores the evidence for the association or dissociation of face and object recognition. Of the 238 CP cases with data permitting a satisfactory evaluation, 80.3% evinced an association between impaired face and object recognition whereas 19.7% evinced a dissociation. We evaluate the strength of the evidence and correlate the face and object recognition behaviour. We consider the implications for theories of functional organization of the visual system, and offer suggestions for further adjudication of the relationship between face and object recognition.
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Affiliation(s)
- Jacob Geskin
- a Department of Psychology and Center for the Neural Basis of Cognition , Carnegie Mellon University , Pittsburgh , PA , USA
| | - Marlene Behrmann
- a Department of Psychology and Center for the Neural Basis of Cognition , Carnegie Mellon University , Pittsburgh , PA , USA
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18
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Spatiotemporal reorganization of the reading network in adult dyslexia. Cortex 2017; 92:204-221. [DOI: 10.1016/j.cortex.2017.04.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Revised: 01/05/2017] [Accepted: 04/12/2017] [Indexed: 12/31/2022]
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19
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Veldsman M, Loetscher T, Wood A, Brodtmann A. Reading on the right when there's nothing left? Probabilistic tractography reveals hemispheric asymmetry in pure alexia. Neurocase 2017; 23:201-209. [PMID: 28789579 DOI: 10.1080/13554794.2017.1364775] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
We present a patient with reading inexpertise and right hemianopia following left posterior cerebral artery (PCA) stroke. We examine the extent of disruption to reading performance and the extent of white matter tract damage relative to a patient with more limited PCA infarction and isolated right hemianopia. We show white matter disconnection of the temporal occipital fusiform cortex in our pure alexia patient. Connectivity-based laterality indices revealed right hemisphere laterality in the alexia patient; this was not associated with improved reading function. We speculate that the degree of premorbid laterality may be a critical factor affecting the extent of reading dysfunction in alexia.
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Affiliation(s)
- Michele Veldsman
- a Nuffield Department of Clinical Neuroscience , University of Oxford , Oxford , UK.,b Behavioural Neuroscience and Stroke Divisions , Florey Institute for Neuroscience and Mental Health , Melbourne , Australia
| | - Tobias Loetscher
- c School of Psychology, Social Work and Social Policy , University of South Australia , Adelaide , Australia
| | - Amanda Wood
- d School of Life and Health Sciences & Aston Brain Centre , Aston University , Birmingham , UK.,e Clinical Sciences , Murdoch Childrens Research Institute , Melbourne , Australia.,f Austin Health , University of Melbourne , Melbourne , Australia
| | - Amy Brodtmann
- b Behavioural Neuroscience and Stroke Divisions , Florey Institute for Neuroscience and Mental Health , Melbourne , Australia.,f Austin Health , University of Melbourne , Melbourne , Australia
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20
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Hanna KL, Hepworth LR, Rowe FJ. The treatment methods for post-stroke visual impairment: A systematic review. Brain Behav 2017; 7:e00682. [PMID: 28523224 PMCID: PMC5434187 DOI: 10.1002/brb3.682] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/03/2016] [Revised: 02/15/2017] [Accepted: 02/16/2017] [Indexed: 12/23/2022] Open
Abstract
AIM To provide a systematic overview of interventions for stroke related visual impairments. METHOD A systematic review of the literature was conducted including randomized controlled trials, controlled trials, cohort studies, observational studies, systematic reviews, and retrospective medical note reviews. All languages were included and translation obtained. This review covers adult participants (aged 18 years or over) diagnosed with a visual impairment as a direct cause of a stroke. Studies which included mixed populations were included if over 50% of the participants had a diagnosis of stroke and were discussed separately. We searched scholarly online resources and hand searched articles and registers of published, unpublished, and ongoing trials. Search terms included a variety of MESH terms and alternatives in relation to stroke and visual conditions. Article selection was performed by two authors independently. Data were extracted by one author and verified by a second. The quality of the evidence and risk of bias was assessed using appropriate tools dependant on the type of article. RESULTS Forty-nine articles (4142 subjects) were included in the review, including an overview of four Cochrane systematic reviews. Interventions appraised included those for visual field loss, ocular motility deficits, reduced central vision, and visual perceptual deficits. CONCLUSION Further high quality randomized controlled trials are required to determine the effectiveness of interventions for treating post-stroke visual impairments. For interventions which are used in practice but do not yet have an evidence base in the literature, it is imperative that these treatments be addressed and evaluated in future studies.
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Affiliation(s)
- Kerry Louise Hanna
- Department of Health Services ResearchUniversity of LiverpoolLiverpoolUK
| | | | - Fiona J. Rowe
- Department of Health Services ResearchUniversity of LiverpoolLiverpoolUK
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21
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Cohen L, Dehaene S, McCormick S, Durant S, Zanker JM. Brain mechanisms of recovery from pure alexia: A single case study with multiple longitudinal scans. Neuropsychologia 2016; 91:36-49. [PMID: 27422538 DOI: 10.1016/j.neuropsychologia.2016.07.009] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2016] [Revised: 07/05/2016] [Accepted: 07/09/2016] [Indexed: 12/01/2022]
Abstract
Pure alexia is an acquired reading disorder, typically due to a left occipito-temporal lesion affecting the Visual Word Form Area (VWFA). It is unclear whether the VWFA acts as a unique bottleneck for reading, or whether alternative routes are available for recovery. Here, we address this issue through the single-case longitudinal study of a neuroscientist who experienced pure alexia and participated in 17 behavioral, 9 anatomical, and 9 fMRI assessment sessions over a period of two years. The origin of the impairment was assigned to a small left fusiform lesion, accompanied by a loss of VWFA responsivity and by the degeneracy of the associated white matter pathways. fMRI experiments allowed us to image longitudinally the visual perception of words, as compared to other classes of stimuli, as well as the mechanisms of letter-by-letter reading. The progressive improvement of reading was not associated with the re-emergence of a new area selective to words, but with increasing responses in spared occipital cortex posterior to the lesion and in contralateral right occipital cortex. Those regions showed a non-specific increase of activations over time and an increase in functional correlation with distant language areas. Those results confirm the existence of an alternative occipital route for reading, bypassing the VWFA, but they also point to its key limitation: the patient remained a slow letter-by-letter reader, thus supporting the critical importance of the VWFA for the efficient parallel recognition of written words.
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Affiliation(s)
- Laurent Cohen
- Inserm, U 1127, F-75013 Paris, France; Sorbonne Universités, UPMC University, Paris 06, UMR S 1127, F-75013 Paris, France; AP-HP, Hôpital de la Pitié Salpêtrière, Department of Neurology, F-75013 Paris, France; CNRS, UMR 7225, F-75013 Paris, France; Institut du Cerveau et de la Moelle épinière, ICM, F-75013 Paris, France.
| | - Stanislas Dehaene
- Collège de France, Place Marcelin Berthelot, 75005 Paris, France; Cognitive Neuroimaging Unit, CEA DSV/I2BM, INSERM, Université Paris-Sud, Université Paris-Saclay, NeuroSpin Center, 91191 Gif/Yvette, France
| | - Samantha McCormick
- Department of Psychology, Royal Holloway, University of London, Egham TW20 0EX, UK; Department of Psychology, University of Roehampton, Whitelands College, Holybourne Avenue, London SW15 4JD, UK
| | - Szonya Durant
- Department of Psychology, Royal Holloway, University of London, Egham TW20 0EX, UK
| | - Johannes M Zanker
- Department of Psychology, Royal Holloway, University of London, Egham TW20 0EX, UK
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22
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Abstract
Understanding the process by which the cerebral hemispheres reach their mature functional organization remains challenging. We propose a theoretical account in which, in the domain of vision, faces and words come to be represented adjacent to retinotopic cortex by virtue of the need to discriminate among homogeneous exemplars. Orthographic representations are further constrained to be proximal to typically left-lateralized language-related information to minimize connectivity length between visual and language areas. As reading is acquired, orthography comes to rely more heavily (albeit not exclusively) on the left fusiform region to bridge vision and language. Consequently, due to competition from emerging word representations, face representations that were initially bilateral become lateralized to the right fusiform region (albeit, again, not exclusively). We review recent research that describes constraints that give rise to this graded hemispheric arrangement. We then summarize empirical evidence from a variety of studies (behavioral, evoked response potential, functional imaging) across different populations (children, adolescents, and adults; left handers and individuals with developmental dyslexia) that supports the claims that hemispheric lateralization is graded rather than binary and that this graded organization emerges dynamically over the course of development. Perturbations of this system either during development or in adulthood provide further insights into the principles governing hemispheric organization.
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Affiliation(s)
- Marlene Behrmann
- Department of Psychology and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania
| | - David C Plaut
- Department of Psychology and Center for the Neural Basis of Cognition, Carnegie Mellon University, Pittsburgh, Pennsylvania
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23
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Lacey EH, Jiang X, Friedman RB, Snider SF, Parra LC, Huang Y, Turkeltaub PE. Transcranial direct current stimulation for pure alexia: effects on brain and behavior. Brain Stimul 2015; 8:305-7. [PMID: 25511797 PMCID: PMC5808439 DOI: 10.1016/j.brs.2014.10.019] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 10/11/2014] [Indexed: 10/24/2022] Open
Affiliation(s)
- E H Lacey
- Department of Neurology, Georgetown University, 4000 Reservoir Road, NW Building D, 165, Washington, DC 20057, USA; MedStar National Rehabilitation Hospital, USA.
| | - X Jiang
- Department of Neuroscience, Georgetown University, USA
| | - R B Friedman
- Department of Neurology, Georgetown University, USA
| | - S F Snider
- Department of Neurology, Georgetown University, USA
| | - L C Parra
- Department of Biomedical Engineering, City College of New York, USA
| | - Y Huang
- Department of Biomedical Engineering, City College of New York, USA
| | - P E Turkeltaub
- Department of Neurology, Georgetown University, USA; MedStar National Rehabilitation Hospital, USA
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24
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Schurz M, Wimmer H, Richlan F, Ludersdorfer P, Klackl J, Kronbichler M. Resting-State and Task-Based Functional Brain Connectivity in Developmental Dyslexia. Cereb Cortex 2014; 25:3502-14. [PMID: 25169986 PMCID: PMC4585499 DOI: 10.1093/cercor/bhu184] [Citation(s) in RCA: 108] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Reading requires the interaction between multiple cognitive processes situated in distant brain areas. This makes the study of functional brain connectivity highly relevant for understanding developmental dyslexia. We used seed-voxel correlation mapping to analyse connectivity in a left-hemispheric network for task-based and resting-state fMRI data. Our main finding was reduced connectivity in dyslexic readers between left posterior temporal areas (fusiform, inferior temporal, middle temporal, superior temporal) and the left inferior frontal gyrus. Reduced connectivity in these networks was consistently present for 2 reading-related tasks and for the resting state, showing a permanent disruption which is also present in the absence of explicit task demands and potential group differences in performance. Furthermore, we found that connectivity between multiple reading-related areas and areas of the default mode network, in particular the precuneus, was stronger in dyslexic compared with nonimpaired readers.
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Affiliation(s)
| | | | | | | | - Johannes Klackl
- Centre for Cognitive Neuroscience Department of Psychology, University of Salzburg, 5020 Salzburg, Austria
| | - Martin Kronbichler
- Centre for Cognitive Neuroscience Neuroscience Institute, Christian Doppler Clinic, Paracelsus Medical University, Ignaz-Harrer-Str. 79, 5020 Salzburg, Austria
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25
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Richlan F. Functional neuroanatomy of developmental dyslexia: the role of orthographic depth. Front Hum Neurosci 2014; 8:347. [PMID: 24904383 PMCID: PMC4033006 DOI: 10.3389/fnhum.2014.00347] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2014] [Accepted: 05/08/2014] [Indexed: 01/21/2023] Open
Abstract
Orthographic depth (OD) (i.e., the complexity, consistency, or transparency of grapheme-phoneme correspondences in written alphabetic language) plays an important role in the acquisition of reading skills. Correspondingly, developmental dyslexia is characterized by different behavioral manifestations across languages varying in OD. This review focuses on the question of whether these different behavioral manifestations are associated with different functional neuroanatomical manifestations. It provides a review and critique of cross-linguistic brain imaging studies of developmental dyslexia. In addition, it includes an analysis of state-of-the-art functional neuroanatomical models of developmental dyslexia together with orthography-specific predictions derived from these models. These predictions should be tested in future brain imaging studies of typical and atypical reading in order to refine the current neurobiological understanding of developmental dyslexia, especially with respect to orthography-specific and universal aspects.
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Affiliation(s)
- Fabio Richlan
- Centre for Neurocognitive Research and Department of Psychology, University of SalzburgSalzburg, Austria
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26
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Barton JJS, Hanif HM, Eklinder Björnström L, Hills C. The word-length effect in reading: A review. Cogn Neuropsychol 2014; 31:378-412. [DOI: 10.1080/02643294.2014.895314] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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