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Chen R, Jiao Y, Zhu JS, Wang XH, Zhao MT. Frequency-specific static and dynamic neural activity indices in children with different attention deficit hyperactivity disorder subtypes: a resting-state fMRI study. Front Hum Neurosci 2024; 18:1412572. [PMID: 39188407 PMCID: PMC11345791 DOI: 10.3389/fnhum.2024.1412572] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2024] [Accepted: 07/17/2024] [Indexed: 08/28/2024] Open
Abstract
Attention deficit hyperactivity disorder (ADHD) is one of the most common neurodevelopmental disorders in childhood. Numerous resting-state functional magnetic resonance imaging (rs-fMRI) studies in ADHD have been performed using traditional low-frequency bands (0.01-0.08 Hz). However, the neural activity patterns of frequency subbands in ADHD still require further investigation. The purpose of this study is to explore the frequency-dependent characteristics and neural activity patterns of ADHD subtypes. We selected the ADHD combined type (ADHD-C, N = 25), ADHD inattentive type (ADHD-I, N = 26) and typically developing (TD, N = 28) children from the ADHD-200 Consortium. Based on the slow-5 band (0.01-0.027 Hz) and slow-4 band (0.027-0.073 Hz), we generated static and dynamic fractional amplitude of low-frequency fluctuation (fALFF) and regional homogeneity (ReHo) maps for each participant. A flexible-factorial analysis of variance model was performed on static and temporal dynamic rs-fMRI measurements within two subbands. Results revealed that the orbital-frontal gyrus, precuneus, superior temporal gyrus and angular gyrus were found to have obvious frequency band and group interaction effects. The intrinsic neural activity differences among three groups were more prominent in the slow-5 frequency band compared to the slow-4 band. In addition, the indices of significant interaction regions showed correlations with the progression of the disease and the features in slow-5 showed an advantageous diagnostic performance compared with those in slow-4. The results suggested the intrinsic neural activities of ADHD subtypes were frequency-dependent. The frequency-specific analysis of static and dynamic brain activity may provide a deeper understanding of neurophysiological dysfunction patterns in ADHD subtypes and provide supplementary information for assessing ADHD subtypes.
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Affiliation(s)
- Ran Chen
- Nurturing Center of Jiangsu Province for State Laboratory of AI Imaging and Interventional Radiology, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, China
- Department of Radiology, Nanjing BenQ Medical Center, the Affiliated BenQ Hospital of Nanjing Medical University, Nanjing, China
| | - Yun Jiao
- Nurturing Center of Jiangsu Province for State Laboratory of AI Imaging and Interventional Radiology, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, China
- Network Information Center, Zhongda Hospital, Medical School of Southeast University, Nanjing, China
| | - Jun-Sa Zhu
- Nurturing Center of Jiangsu Province for State Laboratory of AI Imaging and Interventional Radiology, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, China
| | - Xun-Heng Wang
- Institute of Biomedical Engineering and Instrumentation, Hangzhou Dianzi University, Hangzhou, China
| | - Mei-Ting Zhao
- Nurturing Center of Jiangsu Province for State Laboratory of AI Imaging and Interventional Radiology, Department of Radiology, Zhongda Hospital, Medical School of Southeast University, Nanjing, China
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2
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Reduced parietal activation in participants with mild cognitive impairments during visual-spatial processing measured with functional near-infrared spectroscopy. J Psychiatr Res 2022; 146:31-42. [PMID: 34953303 DOI: 10.1016/j.jpsychires.2021.12.021] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/01/2021] [Revised: 08/02/2021] [Accepted: 12/10/2021] [Indexed: 01/08/2023]
Abstract
Functional Near Infrared Spectroscopy (fNIRS) may be a suitable, simple, and cost-effective brain imaging technique for detecting divergent neuronal patterns at an early stage of neurodegeneration. In course of Mild Cognitive Impairment (MCI) or Alzheimer's disease (AD), a deficit in visual-spatial processing, located in the parietal cortex, is a reliable risk factor. Earlier, we established the application of the clock-hand-angle-discrimination task (ADT) during fNIRS to identify neuronal correlates of the visual-spatial processing in a healthy elderly sample. In this analysis, we aimed to measure and find out differences in the hemodynamic response in MCI participants compared to matched healthy controls. As expected, MCI participants showed more errors over all conditions of pointer length and a higher reaction time in the long and middle pointer length condition. Moreover, results revealed a significant reduction of cortical activation in MCI patients. There was a generally increased activity in both the right as compared to the left hemisphere and the superior parietal brain region as compared to the inferior parietal brain region in both groups. In summary, fNIRS can be implemented in the measurement of visual-spatial processing in MCI patients and healthy elderly based on ADT. MCI participants had difficulties to cope with the ADT. Since neuronal hypoactivity occurs with concomitant behavioral deficits, an additional analysis was performed on a subgroup of MCI patients who performed as well as the control group in behavior. This subgroup analysis also showed a hypoactivation of the parietal cortex, without evidence of a compensatory activation. Therefore, we assume that MCI patients are characterized by a deficit in the parietal cortex. Overall, these findings confirm our hypothesis that hemodynamic deficits in visual-spatial processing, localized in the parietal cortex, are reliable and early diagnostic markers for cognitive decline in risk groups for the development of AD.
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Chai Y, Liu TT, Marrett S, Li L, Khojandi A, Handwerker DA, Alink A, Muckli L, Bandettini PA. Topographical and laminar distribution of audiovisual processing within human planum temporale. Prog Neurobiol 2021; 205:102121. [PMID: 34273456 DOI: 10.1016/j.pneurobio.2021.102121] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 05/20/2021] [Accepted: 07/13/2021] [Indexed: 10/20/2022]
Abstract
The brain is capable of integrating signals from multiple sensory modalities. Such multisensory integration can occur in areas that are commonly considered unisensory, such as planum temporale (PT) representing the auditory association cortex. However, the roles of different afferents (feedforward vs. feedback) to PT in multisensory processing are not well understood. Our study aims to understand that by examining laminar activity patterns in different topographical subfields of human PT under unimodal and multisensory stimuli. To this end, we adopted an advanced mesoscopic (sub-millimeter) fMRI methodology at 7 T by acquiring BOLD (blood-oxygen-level-dependent contrast, which has higher sensitivity) and VAPER (integrated blood volume and perfusion contrast, which has superior laminar specificity) signal concurrently, and performed all analyses in native fMRI space benefiting from an identical acquisition between functional and anatomical images. We found a division of function between visual and auditory processing in PT and distinct feedback mechanisms in different subareas. Specifically, anterior PT was activated more by auditory inputs and received feedback modulation in superficial layers. This feedback depended on task performance and likely arose from top-down influences from higher-order multimodal areas. In contrast, posterior PT was preferentially activated by visual inputs and received visual feedback in both superficial and deep layers, which is likely projected directly from the early visual cortex. Together, these findings provide novel insights into the mechanism of multisensory interaction in human PT at the mesoscopic spatial scale.
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Affiliation(s)
- Yuhui Chai
- Section on Functional Imaging Methods, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA.
| | - Tina T Liu
- Section on Neurocircuitry, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Sean Marrett
- Functional MRI Core, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Linqing Li
- Functional MRI Core, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Arman Khojandi
- Section on Functional Imaging Methods, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Daniel A Handwerker
- Section on Functional Imaging Methods, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
| | - Arjen Alink
- University Medical Centre Hamburg-Eppendorf, Department of Systems Neuroscience, Hamburg, Germany
| | - Lars Muckli
- Institute of Neuroscience and Psychology, University of Glasgow, Glasgow, UK
| | - Peter A Bandettini
- Section on Functional Imaging Methods, Laboratory of Brain and Cognition, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA; Functional MRI Core, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA
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4
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Haberstumpf S, Seidel A, Lauer M, Polak T, Deckert J, Herrmann MJ. Neuronal correlates of the visual-spatial processing measured with functional near-infrared spectroscopy in healthy elderly individuals. Neuropsychologia 2020; 148:107650. [PMID: 33045230 DOI: 10.1016/j.neuropsychologia.2020.107650] [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: 06/04/2020] [Revised: 09/29/2020] [Accepted: 10/02/2020] [Indexed: 12/25/2022]
Abstract
Alzheimer's disease (AD) and Mild Cognitive Impairment (MCI) are a globally rising issue. It is necessary to detect such diseases early to find strategies for prevention. Typically, patients with MCI or AD show deviant neuronal patterns, which could be detected early through brain imaging techniques enabling assumptions about pre-existing diseases. Functional Near-Infrared Spectroscopy (fNIRS) is an appropriate imaging method because of its easy and economical nature with hardly any drawbacks. An early measurable risk factor indicating neurodegenerative processes could be a deficit in visual-spatial processing, which is localized in the parietal cortex. In this study, we aimed to measure the hemodynamic response of the visual-spatial processing in the healthy elderly participants of our long-term Vogel Study with fNIRS during the clock-hand-angle-discrimination task (ADT) to deepen our understanding of healthy brain mechanisms. Our results revealed for our healthy sample a significantly increased neuronal brain activity with increasing task difficulties, namely from the long to the middle to the short clock hand during ADT and significantly higher activation in the right hemisphere compared to the left hemisphere as well as in the superior parietal cortex compared to the inferior parietal cortex. Additionally, our behavioral data demonstrated longer reaction times and more errors with an increasing task requirement. We, therefore, assume that visual-spatial processing can successfully be operationalized with fNIRS for healthy elderly people based on ADT. Further fNIRS analyses are planned to investigate pathological neuronal correlates of visual-spatial function in MCI or AD study participants.
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Affiliation(s)
- Sophia Haberstumpf
- Center for Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, Margarete-Höppel-Platz 1, D - 97080, Würzburg, Germany
| | - Alexandra Seidel
- Center for Mental Health, Department of Child and Adolescent Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, Margarete-Höppel-Platz 1, D - 97080, Würzburg, Germany
| | - Martin Lauer
- Center for Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, Margarete-Höppel-Platz 1, D - 97080, Würzburg, Germany
| | - Thomas Polak
- Center for Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, Margarete-Höppel-Platz 1, D - 97080, Würzburg, Germany
| | - Jürgen Deckert
- Center for Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, Margarete-Höppel-Platz 1, D - 97080, Würzburg, Germany
| | - Martin J Herrmann
- Center for Mental Health, Department of Psychiatry, Psychosomatics and Psychotherapy, University Hospital Würzburg, Margarete-Höppel-Platz 1, D - 97080, Würzburg, Germany.
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Bartley JE, Boeving ER, Riedel MC, Bottenhorn KL, Salo T, Eickhoff SB, Brewe E, Sutherland MT, Laird AR. Meta-analytic evidence for a core problem solving network across multiple representational domains. Neurosci Biobehav Rev 2018; 92:318-337. [PMID: 29944961 PMCID: PMC6425494 DOI: 10.1016/j.neubiorev.2018.06.009] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2017] [Revised: 06/11/2018] [Accepted: 06/11/2018] [Indexed: 12/21/2022]
Abstract
Problem solving is a complex skill engaging multi-stepped reasoning processes to find unknown solutions. The breadth of real-world contexts requiring problem solving is mirrored by a similarly broad, yet unfocused neuroimaging literature, and the domain-general or context-specific brain networks associated with problem solving are not well understood. To more fully characterize those brain networks, we performed activation likelihood estimation meta-analysis on 280 neuroimaging problem solving experiments reporting 3166 foci from 1919 individuals across 131 papers. The general map of problem solving revealed broad fronto-cingulo-parietal convergence, regions similarly identified when considering separate mathematical, verbal, and visuospatial problem solving domain-specific analyses. Conjunction analysis revealed a common network supporting problem solving across diverse contexts, and difference maps distinguished functionally-selective sub-networks specific to task type. Our results suggest cooperation between representationally specialized sub-network and whole-brain systems provide a neural basis for problem solving, with the core network contributing general purpose resources to perform cognitive operations and manage problem demand. Further characterization of cross-network dynamics could inform neuroeducational studies on problem solving skill development.
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Affiliation(s)
- Jessica E Bartley
- Department of Physics, Florida International University, Miami, FL, USA
| | - Emily R Boeving
- Department of Psychology, Florida International University, Miami, FL, USA
| | - Michael C Riedel
- Department of Physics, Florida International University, Miami, FL, USA
| | | | - Taylor Salo
- Department of Psychology, Florida International University, Miami, FL, USA
| | - Simon B Eickhoff
- Institute for Systems Neuroscience, Medical Faculty, Heinrich Heine University Dusseldorf, Düsseldorf, Germany; Institute of Neuroscience and Medicine, Brain & Behavior (INM-7), Research Center Jülich, Jülich, Germany
| | - Eric Brewe
- Department of Teaching and Learning, Florida International University, Miami, FL, USA; Department of Physics, Drexel University, Philadelphia, PA, USA; Department of Education, Drexel University, Philadelphia, PA, USA
| | | | - Angela R Laird
- Department of Physics, Florida International University, Miami, FL, USA.
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Vergallito A, Romero Lauro LJ, Bonandrini R, Zapparoli L, Danelli L, Berlingeri M. What is difficult for you can be easy for me. Effects of increasing individual task demand on prefrontal lateralization: A tDCS study. Neuropsychologia 2018; 109:283-294. [DOI: 10.1016/j.neuropsychologia.2017.12.038] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2017] [Revised: 11/22/2017] [Accepted: 12/23/2017] [Indexed: 10/18/2022]
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7
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Polak T, Herrmann MJ, Müller LD, Zeller JBM, Katzorke A, Fischer M, Spielmann F, Weinmann E, Hommers L, Lauer M, Fallgatter AJ, Deckert J. Near-infrared spectroscopy (NIRS) and vagus somatosensory evoked potentials (VSEP) in the early diagnosis of Alzheimer’s disease: rationale, design, methods, and first baseline data of the Vogel study. J Neural Transm (Vienna) 2017; 124:1473-1488. [DOI: 10.1007/s00702-017-1781-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2017] [Accepted: 08/23/2017] [Indexed: 01/06/2023]
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8
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Oveisgharan S, Hachinski V. Simple Neuropsychological Tests May Identify Participants in Whom Aspirin Use Is Associated With Lower Dementia Incidence: The Canadian Study of Health and Aging. Am J Alzheimers Dis Other Demen 2016; 31:545-550. [PMID: 26705378 PMCID: PMC10852575 DOI: 10.1177/1533317515619480] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/03/2024]
Abstract
BACKGROUND We hypothesized that neuropsychological tests could help in identifying preclinical stages of vascular cognitive impairment, when aspirin use might be associated with lower dementia incidence. METHODS We used data of Canadian Study of Health and Aging (CSHA) which was a longitudinal study of Canadians older than 65 years and was done in 3 waves, 1991 to 1992 (CSHA-1), 1996 to 1997 (CSHA-2), and 2001 to 2002. RESULTS CSHA-1 participants with vascular dementia performed worse in copying pentagons and writing subtests of modified Mini-Mental State Examination test than participants with probable Alzheimer's disease. Salicylates use was associated with lower incident dementia among normal cognition CSHA-1 participants who had low scores in copying pentagons and writing subtests after controlling for age, sex, education, and vascular risk factors (odds ratio = 0.25, 95% confidence interval: 0.073-0.86, P = .028). CONCLUSIONS Two simple neuropsychological tests might help in identifying preclinical stages of vascular cognitive impairment, and salicylates use was associated with lower dementia incidence.
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Affiliation(s)
- Shahram Oveisgharan
- RUSH Alzheimer's Disease Center, Rush University Medical Center, Chicago, IL, USA Neurology Department, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran
| | - Vladimir Hachinski
- Department of Clinical Neurological Sciences, University Hospital, University of Western Ontario, London, Ontario, Canada
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9
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Differential recruitment of brain networks during visuospatial and color processing: Evidence from ERP microstates. Neuroscience 2015; 305:128-38. [PMID: 26241335 DOI: 10.1016/j.neuroscience.2015.07.078] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Revised: 07/02/2015] [Accepted: 07/28/2015] [Indexed: 11/21/2022]
Abstract
Recent functional magnetic resonance imaging (fMRI) studies consistently revealed contributions of fronto-parietal and related networks to the execution of a visuospatial judgment task, the so-called "Clock Task". However, due to the low temporal resolution of fMRI, the exact cortical dynamics and timing of processing during task performance could not be resolved until now. In order to clarify the detailed cortical activity and temporal dynamics, 14 healthy subjects performed an established version of the "Clock Task", which comprises a visuospatial task (angle discrimination) and a control task (color discrimination) with the same stimulus material, in an electroencephalography (EEG) experiment. Based on the time-resolved analysis of network activations (microstate analysis), differences in timing between the angle compared to the color discrimination task were found after sensory processing in a time window starting around 200 ms. Significant differences between the two tasks were observed in an analysis window from 192 ms to 776 ms. We divided this window in two parts: an early phase - from 192 ms to ∼440 ms, and a late phase - from ∼440 ms to 776 ms. For both tasks, the order of network activations and the types of networks were the same, but, in each phase, activations for the two conditions were dominated by differing network states with divergent temporal dynamics. Our results provide an important basis for the assessment of deviations in processing dynamics during visuospatial tasks in clinical populations.
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10
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The role of the posterior parietal cortex in stereopsis and hand-eye coordination during motor task behaviours. Cogn Process 2014; 16:177-90. [PMID: 25394882 DOI: 10.1007/s10339-014-0641-1] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2014] [Accepted: 10/28/2014] [Indexed: 10/24/2022]
Abstract
The field of 'Neuroergonomics' has the potential to improve safety in high-risk operative environments through a better appreciation of the way in which the brain responds during human-tool interactions. This is especially relevant to minimally invasive surgery (MIS). Amongst the many challenges imposed on the surgeon by traditional MIS (laparoscopy), arguably the greatest is the loss of depth perception. Robotic MIS platforms, on the other hand, provide the surgeon with a magnified three-dimensional view of the environment, and as a result may offload a degree of the cognitive burden. The posterior parietal cortex (PPC) plays an integral role in human depth perception. Therefore, it can be hypothesized that differences in PPC activation between monoscopic and stereoscopic vision may be observed. In order to investigate this hypothesis, the current study explores disparities in PPC responses between monoscopic and stereoscopic visual perception to better de-couple the burden imposed by laparoscopy and robotic surgery on the operator's brain. Fourteen participants conducted tasks of depth perception and hand-eye coordination under both monoscopic and stereoscopic visual feedback. Cortical haemodynamic responses were monitored throughout using optical functional neuroimaging. Overall, recruitment of the bilateral superior parietal lobule was observed during both depth perception and hand-eye coordination tasks. This occurred contrary to our hypothesis, regardless of the mode of visual feedback. Operator technical performance was significantly different in two- and three-dimensional visual displays. These differences in technical performance do not appear to be explained by significant differences in parietal lobe processing.
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11
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McLeod KR, Langevin LM, Goodyear BG, Dewey D. Functional connectivity of neural motor networks is disrupted in children with developmental coordination disorder and attention-deficit/hyperactivity disorder. NEUROIMAGE-CLINICAL 2014; 4:566-75. [PMID: 24818082 PMCID: PMC3984446 DOI: 10.1016/j.nicl.2014.03.010] [Citation(s) in RCA: 116] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2013] [Revised: 03/19/2014] [Accepted: 03/24/2014] [Indexed: 11/16/2022]
Abstract
Developmental coordination disorder (DCD) and attention deficit/hyperactivity disorder (ADHD) are prevalent childhood disorders that frequently co-occur. Evidence from neuroimaging research suggests that children with these disorders exhibit disruptions in motor circuitry, which could account for the high rate of co-occurrence. The primary objective of this study was to investigate the functional connections of the motor network in children with DCD and/or ADHD compared to typically developing controls, with the aim of identifying common neurophysiological substrates. Resting-state fMRI was performed on seven children with DCD, 21 with ADHD, 18 with DCD + ADHD and 23 controls. Resting-state connectivity of the primary motor cortex was compared between each group and controls, using age as a co-factor. Relative to controls, children with DCD and/or ADHD exhibited similar reductions in functional connectivity between the primary motor cortex and the bilateral inferior frontal gyri, right supramarginal gyrus, angular gyri, insular cortices, amygdala, putamen, and pallidum. In addition, children with DCD and/or ADHD exhibited different age-related patterns of connectivity, compared to controls. These findings suggest that children with DCD and/or ADHD exhibit disruptions in motor circuitry, which may contribute to problems with motor functioning and attention. Our results support the existence of common neurophysiological substrates underlying both motor and attention problems.
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Key Words
- ADHD, attention deficit/hyperactivity disorder
- Attention-deficit/hyperactivity disorder
- DCD, developmental coordination disorder
- DSM-IV, Diagnostic and Statistical Manual of Mental Disorders (4th edition)
- DTI, diffusion tensor imaging
- Developmental coordination disorder
- FC, functional connectivity
- Functional connectivity
- GLM general, linear model
- ICA, independent component analysis
- M1, primary motor cortex
- PFC, prefrontal cortex
- Resting state fMRI, Motor networks
- fMRI, functional magnetic resonance imaging
- rs-fMRI, resting-state fMRI
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Affiliation(s)
- Kevin R McLeod
- Medical Science, University of Calgary, Calgary, Alberta, Canada ; Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, Alberta, Canada
| | - Lisa Marie Langevin
- Department of Paediatrics, University of Calgary, Calgary, Alberta, Canada ; Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, Alberta, Canada ; Behavioural Research Unit, Alberta Children's Hospital, Calgary, Alberta, Canada
| | - Bradley G Goodyear
- Department of Radiology, University of Calgary, Calgary, Alberta, Canada ; Department of Psychiatry, University of Calgary, Calgary, Alberta, Canada ; Department of Clinical Neurosciences, University of Calgary, Calgary, Alberta, Canada ; Seaman Family MR Research Centre, University of Calgary, Calgary, Alberta, Canada ; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Deborah Dewey
- Department of Paediatrics, University of Calgary, Calgary, Alberta, Canada ; Alberta Children's Hospital Research Institute for Child and Maternal Health, University of Calgary, Calgary, Alberta, Canada ; Behavioural Research Unit, Alberta Children's Hospital, Calgary, Alberta, Canada ; Department of Community Health Sciences, University of Calgary, Calgary, Alberta, Canada ; Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
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Shetreet E, Chierchia G, Gaab N. When some is not every: dissociating scalar implicature generation and mismatch. Hum Brain Mapp 2013; 35:1503-14. [PMID: 23568365 DOI: 10.1002/hbm.22269] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2012] [Revised: 01/07/2013] [Accepted: 01/08/2013] [Indexed: 11/09/2022] Open
Abstract
Making inferences beyond the literal meaning of sentences occurs with certain scalar expressions via scalar implicatures. For example, adults usually interpret some as some but not all. On the basis of behavioral research, it has been suggested that processing implicatures is cognitively costly. However, many studies have used cases where sentences with some did not match the context in which they were presented. Our study aimed to examine whether the processing cost is linked to implicature generation, to the mismatch between the implicature and the context, or to both processes. To do so, we explored the neural patterns of implicature generation and implicature mismatch using fMRI. Thirteen participants performed a sentence-picture matching task (where pictures determined the context) with mismatched implicatures, successful implicatures or no implicature conditions. Several brain regions were identified when comparing cases of implicature mismatch and cases without implicatures. One of these regions, left-IFG, was jointly activated for mismatched and successful implicatures, as observed in a conjunction analysis. By contrast, left-MFG and medial-frontal-gyrus, were identified when comparing cases of implicature mismatch with cases of successful implicatures. Thus, the left IFG can be interpreted as being linked to implicature generation, whereas the other two areas seem to participate in the processing of the mismatch between the implicature and its context. Our results indicate that scalar implicatures induce processing cost in different ways. This should be considered in future research.
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Affiliation(s)
- Einat Shetreet
- Laboratories of Cognitive Neuroscience, Division of Developmental Medicine, Department of Medicine, Children's Hospital Boston, Boston, Massachusetts; Department of Linguistics, Harvard University, Cambridge, Massachusetts
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Compromised visually guided motor control in individuals with Alzheimer's disease: can reliable distinctions be observed? J Clin Neurosci 2012; 19:655-60. [PMID: 22459181 DOI: 10.1016/j.jocn.2011.09.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2011] [Accepted: 09/27/2011] [Indexed: 11/21/2022]
Abstract
Identifying the multitude of deficits associated with dementia-related illnesses such as Alzheimer's disease (AD) presents a significant challenge for many health care facilities, particularly as current screening procedures may lack the sensitivity to highlight all the relative functional deficits within these populations. Although quick assessment screening tools, such as the Mini Mental State Exam (MMSE), have been the mainstay in screening patients worldwide, there are limitations to their ability in identifying visuomotor (VM) impairment. Thus, the primary objective of this research was to evaluate the presence and level of VM ability/deficits in healthy normal controls (NC) and populations with AD. The research also aimed to demonstrate that a VM measure can be utilized successfully in a busy health care setting. Results showed a clear distinction between the AD and NC groups on the VM measure. Large effect size differences were observed between groups, particularly as the VM task progressed through its varying conditions. In addition, this novel VM assessment measure demonstrated good presentation and speed and was appropriate for frontline staff in a primary healthcare setting to undertake further examination of an individual's overall visually guided ability/control.
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Hoppe C, Fliessbach K, Stausberg S, Stojanovic J, Trautner P, Elger CE, Weber B. A key role for experimental task performance: Effects of math talent, gender and performance on the neural correlates of mental rotation. Brain Cogn 2012; 78:14-27. [DOI: 10.1016/j.bandc.2011.10.008] [Citation(s) in RCA: 86] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2011] [Revised: 10/13/2011] [Accepted: 10/18/2011] [Indexed: 01/22/2023]
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15
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Chaves S, Vannini P, Jann K, Wurtz P, Federspiel A, Nyffeler T, Luethi M, Hubl D, Wiest R, Dierks T, Müri RM. The link between visual exploration and neuronal activity: A multi-modal study combining eye tracking, functional magnetic resonance imaging and transcranial magnetic stimulation. Neuroimage 2012; 59:3652-61. [DOI: 10.1016/j.neuroimage.2011.10.094] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2010] [Revised: 08/15/2011] [Accepted: 10/31/2011] [Indexed: 11/26/2022] Open
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Ebner K, Lidzba K, Hauser TK, Wilke M. Assessing language and visuospatial functions with one task: a "dual use" approach to performing fMRI in children. Neuroimage 2011; 58:923-9. [PMID: 21726649 DOI: 10.1016/j.neuroimage.2011.06.048] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2011] [Revised: 06/09/2011] [Accepted: 06/16/2011] [Indexed: 12/30/2022] Open
Abstract
In order to increase the rate of successful functional MR studies in children it is helpful to shorten the time spent in the scanner. To this effect, assessing two cognitive functions with one task seems to be a promising approach. The hypothesis of this study was that the control condition of an established language task (vowel identification task, VIT) requires visuospatial processing and that the control condition (VIT(CC)) therefore may also be applicable to localize visuospatial functions. As a reference task, a visual search task (VST, previously established for use in children) was employed. To test this hypothesis, 43 children (19 f, 24 m; 12.0±2.6, range 7.9 to 17.8 years) were recruited and scanned using both tasks. Second-level random effects group analyses showed activation of left inferior-frontal cortex in the active condition of the VIT, as in previous studies. Additionally, analysis of the VIT(CC) demonstrated activation in right-dominant superior parietal and high-frontal brain regions, classically associated with visuospatial functions; activation seen in the VST was similar with a substantial overlap. However, lateralization in the parietal lobe was significantly more bilateral in the VST than in the VIT(CC). This suggests that the VIT can not only be applied to assess language functions (using the active>control contrast), but also that the control>active condition is useful for assessing visuospatial functions. Future task design may benefit from such a "dual use" approach to performing fMRI not only, but also particularly in children.
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Affiliation(s)
- Kathina Ebner
- Pediatric Neurology & Developmental Medicine and Experimental Pediatric Neuroimaging, Children's Hospital University of Tübingen, Tübingen, Germany
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Gender-related differences in changes in the coherence of cortical biopotentials during image-based creative thought: relationship with action efficacy. ACTA ACUST UNITED AC 2010; 40:793-9. [PMID: 20635209 DOI: 10.1007/s11055-010-9328-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2008] [Accepted: 02/09/2009] [Indexed: 10/19/2022]
Abstract
The aim of the present work was to study the characteristics of cortical interactions during performance of an image-based creative task in men and women with high and low levels of creativity. Subjects were divided into groups on the basis of the median originality score. EEG recordings were made in baseline conditions and during performance of the task (the Torrance Tests of Creating Thinking, "Incomplete Figures"). EEG coherence was calculated in six frequency ranges, from theta1 to beta2. Total coherence was analyzed for each of 16 leads calculated separately for intrahemisphere and interhemisphere coherence links. Differences in changes in coherence evoked by performing the task between subjects with high and low levels of originality were seen at the theta2, alpha1, and alpha2 frequencies. These differences resulted from decreases in coherence at low levels of originality, accompanied by increases in coherence in the theta1 and alpha 2 ranges and, at high levels of originality, a less significant decrease in the alpha2 range. The alpha2 range also showed an interaction between the gender, creativity, laterality, and electrode position factors on analysis of task performance-linked intrahemisphere coherence of cortical biopotentials. The patterns of the spatial distributions of coherence across the hemispheres were found to be similar in men and women with opposite levels of creativity, while task-linked changes in coherence in the anterior areas of the left and posterior areas of the right hemisphere were larger in high-creativity men as compared with those with low creativity. The results are evaluated in relation to the possibility that men and women use different cognitive strategies to achieve identical results from creative activity.
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Jann K, Koenig T, Dierks T, Boesch C, Federspiel A. Association of individual resting state EEG alpha frequency and cerebral blood flow. Neuroimage 2010; 51:365-72. [DOI: 10.1016/j.neuroimage.2010.02.024] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2009] [Revised: 02/03/2010] [Accepted: 02/10/2010] [Indexed: 10/19/2022] Open
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Altered parietal brain oxygenation in Alzheimer's disease as assessed with near-infrared spectroscopy. Am J Geriatr Psychiatry 2010; 18:433-41. [PMID: 20220582 DOI: 10.1097/jgp.0b013e3181c65821] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE Visuospatial deficits are among the first symptoms of Alzheimer disease (AD) and linked to lower activation in the superior parietal cortex as assessed with functional imaging. Near-infrared spectroscopy (NIRS) is an optical method to measure changes in the concentration of oxygenated hemoglobin and deoxygenated hemoglobin in the microvascular system of the cortex. Because of its advantages in measurement situation, NIRS has proven to be especially suited for investigating psychiatric patients. The aim of this study was to probe the activation of parietal regions in patients with AD, performing a visuospatial task by means of functional NIRS (fNIRS). METHODS Thirteen patients with suspected mild AD and 13 healthy subjects comparable in age and gender were investigated while working on a modified version of the Benton Line Orientation Task. RESULTS During the spatial task, healthy subjects showed explicit parietal activation, whereas patients displayed only activation during the control task. Interestingly, there was no difference in visuospatial performance between the two groups. CONCLUSION The results indicate that fNIRS is able to measure parietal activation deficits in patients with AD, which could be developed into an early detection method in the future.
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Perneczky R, Drzezga A, Boecker H, Ceballos-Baumann AO, Valet M, Feurer R, Förstl H, Kurz A, Häussermann P. Metabolic alterations associated with impaired clock drawing in Lewy body dementia. Psychiatry Res 2010; 181:85-9. [PMID: 20074912 DOI: 10.1016/j.pscychresns.2009.08.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/17/2007] [Revised: 08/03/2009] [Accepted: 08/03/2009] [Indexed: 11/29/2022]
Abstract
The clock drawing test (CDT) is a widely used dementia screening instrument that assesses executive and visuospatial abilities; studies in patients with Alzheimer's disease (AD) suggest frontoposterior networks to be involved in clock drawing. Clock drawing errors are also often observed in dementia with Lewy bodies (DLB), but the functional neuroanatomical substrate of impaired clock drawing has not been firmly established in this disorder. The present study was designed to provide initial evidence for brain metabolic alterations associated with CDT performance in DLB. Twenty-one patients with DLB were enrolled. CDT ratings were correlated with the regional cerebral metabolic rate of glucose (rCMRglc) measured by (18)F-fluoro-2-deoxy-glucose positron emission tomography ((18)F-FDG PET) in the statistical parametric mapping software package SPM5, controlling for overall cognitive impairment as measured by the Mini-Mental-State Examination (MMSE) score. There was a significant negative association between test scores and rCMRglc in a left-hemispheric posterofrontal network including the temporoparietal and dorsal pre-motor cortices and the precuneus. The present study provides evidence for a direct association between frontoparietal dysfunction and impaired CDT performance in DLB. These findings also suggest that the CDT is an appropriate screening instrument for this disorder and that metabolic dysfunction, and therefore disease severity, is mirrored by performance on the test.
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Affiliation(s)
- Robert Perneczky
- Department of Psychiatry and Psychotherapy, Technische Ismaninger Str. 22, 81675 München, Germany.
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21
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Sack AT. Parietal cortex and spatial cognition. Behav Brain Res 2009; 202:153-61. [PMID: 19463696 DOI: 10.1016/j.bbr.2009.03.012] [Citation(s) in RCA: 129] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2009] [Revised: 03/04/2009] [Accepted: 03/06/2009] [Indexed: 01/15/2023]
Affiliation(s)
- Alexander T Sack
- Department of Cognitive Neuroscience, Faculty of Psychology and Neuroscience, Maastricht University, P.O. Box 616, 6200 MD Maastricht, The Netherlands.
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Feldmann A, Trauninger A, Toth L, Kotek G, Kosztolanyi P, Illes E, Pfund Z, Komoly S, Nagy F, Illes Z. Atrophy and decreased activation of fronto-parietal attention areas contribute to higher visual dysfunction in posterior cortical atrophy. Psychiatry Res 2008; 164:178-84. [PMID: 18945600 DOI: 10.1016/j.pscychresns.2008.01.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2007] [Revised: 12/05/2007] [Accepted: 01/13/2008] [Indexed: 11/26/2022]
Abstract
Voxel-based morphometry and functional magnetic resonance imaging demonstrated severe atrophy and decreased activation of visual attention areas and occipital lobes in a patient with early posterior cortical atrophy compared with healthy controls and patients with early Alzheimer's disease. Our complex approach indicates that structures responsible for attention can be damaged early in posterior cortical atrophy and may contribute to the characteristic decline in higher visual functions.
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Affiliation(s)
- Adam Feldmann
- Department of Neurology, University of Pecs, 2 Ret St, Pecs, 7623 Hungary
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Vannini P, Lehmann C, Dierks T, Jann K, Viitanen M, Wahlund LO, Almkvist O. Failure to modulate neural response to increased task demand in mild Alzheimer's disease: fMRI study of visuospatial processing. Neurobiol Dis 2008; 31:287-97. [DOI: 10.1016/j.nbd.2008.04.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Revised: 04/25/2008] [Accepted: 04/30/2008] [Indexed: 11/16/2022] Open
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Vannini P, Almkvist O, Dierks T, Lehmann C, Wahlund LO. Reduced neuronal efficacy in progressive mild cognitive impairment: a prospective fMRI study on visuospatial processing. Psychiatry Res 2007; 156:43-57. [PMID: 17719211 DOI: 10.1016/j.pscychresns.2007.02.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/03/2006] [Revised: 01/19/2007] [Accepted: 02/12/2007] [Indexed: 11/18/2022]
Abstract
Mild cognitive impairment (MCI) often refers to the preclinical stage of dementia, where the majority develop Alzheimer's disease (AD). Given that neurodegenerative burden and compensatory mechanisms might exist before accepted clinical symptoms of AD are noticeable, the current prospective study aimed to investigate the functioning of brain regions in the visuospatial networks responsible for preclinical symptoms in AD using event-related functional magnetic resonance imaging (fMRI). Eighteen MCI patients were evaluated and clinically followed for approximately 3 years. Five progressed to AD (PMCI) and eight remained stable (SMCI). Thirteen age-, gender- and education-matched controls also participated. An angle discrimination task with varying task demands was used. Brain activation patterns as well as task demand-dependent and -independent signal changes between the groups were investigated by using an extended general linear model including individual performance (reaction time [RT]) of each single trial. Similar behavioral (RT and accuracy) responses were observed between MCI patients and controls. A network of bilateral activations, e.g. dorsal pathway, which increased linearly with increasing task demand, was engaged in all subjects. Compared with SMCI patients and controls, PMCI patients showed a stronger relation between task demand and brain activity in left superior parietal lobules (SPL) as well as a general task demand-independent increased activation in left precuneus. Altered brain function can be detected at a group level in individuals that progress to AD before changes occur at the behavioral level. Increased parietal activation in PMCI could reflect a reduced neuronal efficacy due to accumulating AD pathology and might predict future clinical decline in patients with MCI.
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Affiliation(s)
- Patrizia Vannini
- Department of Neurobiology, Care Sciences and Society, Division of Clinical Geriatrics, Karolinska Institutet, Karolinska University Hospital, Huddinge, 141 86 Stockholm, Sweden.
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Stella F, Gobbi LTB, Gobbi S, Oliani MM, Tanaka K, Pieruccini-Faria F. Early impairment of cognitive functions in Parkinson's disease. ARQUIVOS DE NEURO-PSIQUIATRIA 2007; 65:406-10. [PMID: 17665005 DOI: 10.1590/s0004-282x2007000300008] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2006] [Accepted: 02/14/2007] [Indexed: 11/22/2022]
Abstract
BACKGROUND: Impairment in non-motor functions such as disturbances of some executive functions are also common events in Parkinson's disease patients. OBJECTIVE: To verify the performance of Parkinson's disease patients in activities requiring visuoconstructive and visuospatial skills. METHOD: Thirty elderly patients with mild or moderate stages of Parkinson's disease were studied. The assessment of the clinical condition was based on the unified Parkinson's disease rating scale (56.28; SD=33.48), Hoehn and Yahr (2.2; SD=0.83), Schwab and England (78.93%), clock drawing test (7.36; SD=2.51), and mini-mental state examination (26.48; SD=10.11). Pearson's correlation and stepwise multiple regression were used for statistical analyses. RESULTS: The patients presented deterioration in visuospatial and visuoconstructive skills. CONCLUSION: The clock drawing test proved to be a useful predictive tool for identifying early cognitive impairment in thesbe individuals.
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Affiliation(s)
- Florindo Stella
- Neuropsychiatry and Mental Health for Elderly, State University of Campinas, Campinas, SP, Brazil.
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Sack AT, Kohler A, Bestmann S, Linden DEJ, Dechent P, Goebel R, Baudewig J. Imaging the brain activity changes underlying impaired visuospatial judgments: simultaneous FMRI, TMS, and behavioral studies. ACTA ACUST UNITED AC 2007; 17:2841-52. [PMID: 17337745 DOI: 10.1093/cercor/bhm013] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Damage to parietal cortex impairs visuospatial judgments. However, it is currently unknown how this damage may affect or indeed be caused by functional changes in remote but interconnected brain regions. Here, we applied transcranial magnetic stimulation (TMS) to the parietal cortices during functional magnetic resonance imaging (fMRI) while participants were solving visuospatial tasks. This allowed us to observe both the behavioral and the neural effects of transient parietal activity disruption in the active healthy human brain. Our results show that right, but not left, parietal TMS impairs visuospatial judgment, induces neural activity changes in a specific right-hemispheric network of frontoparietal regions, and shows significant correlations between the induced behavioral impairment and neural activity changes in both the directly stimulated parietal and remote ipsilateral frontal brain regions. The revealed right-hemispheric neural network effect of parietal TMS represents the same brain areas that are functionally connected during the execution of visuospatial judgments. This corroborates the notion that visuospatial deficits following parietal damage are brought about by a perturbation of activity across a specific frontoparietal network, rather than the lesioned parietal site alone. Our experiments furthermore show how concurrent fMRI and magnetic brain stimulation during active task execution hold the potential to identify and visualize networks of brain areas that are functionally related to specific cognitive processes.
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Affiliation(s)
- Alexander T Sack
- Department of Cognitive Neuroscience, Faculty of Psychology, Maastricht University, 6200 MD Maastricht, The Netherlands.
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Effects of single-trial averaging on spatial extent of brain activation detected by fMRI are subject and task dependent. Biomed Imaging Interv J 2006; 2:e27. [PMID: 21614241 PMCID: PMC3097634 DOI: 10.2349/biij.2.3.e27] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2006] [Revised: 04/12/2006] [Accepted: 04/20/2006] [Indexed: 11/17/2022] Open
Abstract
Aim The effects of single-trial averaging on the spatial extent of event-related fMRI activation may vary between subjects and tasks. The purpose of this study was to evaluate this variability using a visual task and a word generation task. Patients, materials, and methods Five Chinese right-handed male volunteers participated in the experiment. Experiments were conducted using a 1.5 T clinical MRI scanner with a T2*-weighted single-shot gradient-echo EPI sequence. Each task contained 150 trials that were separated into 5 runs. For each voxel, time courses averaged across different numbers of randomly selected trials, were obtained. They were applied for determining the voxels with significant activations, using a students’ t-test (p<0.001, uncorrected). Results Consistent with previous findings, the number of the activated voxels increased monotonically with the number of trials combined. The ascending rate and the maximum number of the activated voxels were different, however, between tasks and among subjects. Conclusions The effects of single-trial averaging were found to vary significantly between tasks and subjects. Therefore, we strongly advise to carefully consider such variability when using the spatial extent of activation as a measure in a group or a task comparison.
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Lehmann C, Vannini P, Wahlund LO, Almkvist O, Dierks T. Increased sensitivity in mapping task demand in visuospatial processing using reaction-time-dependent hemodynamic response predictors in rapid event-related fMRI. Neuroimage 2006; 31:505-12. [PMID: 16564707 DOI: 10.1016/j.neuroimage.2005.12.064] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2005] [Revised: 12/05/2005] [Accepted: 12/30/2005] [Indexed: 11/20/2022] Open
Abstract
Searching for the neural correlates of visuospatial processing using functional magnetic resonance imaging (fMRI) is usually done in an event-related framework of cognitive subtraction, applying a paradigm comprising visuospatial cognitive components and a corresponding control task. Besides methodological caveats of the cognitive subtraction approach, the standard general linear model with fixed hemodynamic response predictors bears the risk of being underspecified. It does not take into account the variability of the blood oxygen level-dependent signal response due to variable task demand and performance on the level of each single trial. This underspecification may result in reduced sensitivity regarding the identification of task-related brain regions. In a rapid event-related fMRI study, we used an extended general linear model including single-trial reaction-time-dependent hemodynamic response predictors for the analysis of an angle discrimination task. In addition to the already known regions in superior and inferior parietal lobule, mapping the reaction-time-dependent hemodynamic response predictor revealed a more specific network including task demand-dependent regions not being detectable using the cognitive subtraction method, such as bilateral caudate nucleus and insula, right inferior frontal gyrus and left precentral gyrus.
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Affiliation(s)
- Christoph Lehmann
- Department of Psychiatric Neurophysiology, University Hospital of Clinical Psychiatry, Waldau, CH-3000 Bern 60, Switzerland
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Prvulovic D, Van de Ven V, Sack AT, Maurer K, Linden DEJ. Functional activation imaging in aging and dementia. Psychiatry Res 2005; 140:97-113. [PMID: 16257186 DOI: 10.1016/j.pscychresns.2005.06.006] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/28/2004] [Revised: 01/06/2005] [Accepted: 06/25/2005] [Indexed: 11/24/2022]
Abstract
With life expectancy increasing continuously, the effects of neurodegeneration on brain function are a topic of ever increasing importance. Thus there is a need for tools and models that probe both the functional consequences of neurodegenerative processes and compensatory mechanisms that might occur. As neurodegenerative burden and compensatory mechanisms may change over time, these tools will ideally be applied multiple times over the lifespan. Specifically, in order to elucidate whether brain-activation patterns in Alzheimer's disease (AD) and in healthy aging follow general rules in the context of degeneration and compensation, it is necessary to compare functional brain-activation patterns during different states of neurodegeneration. This article integrates the findings of functional activation studies at different stages of neurodegeneration: in healthy aging, in subjects at high risk of developing dementia, in subjects with mild cognitive impairment (MCI), and in patients suffering from AD. We review existing theoretical models that aim to explain the underlying mechanisms of functional activation changes in aging and dementia, and we propose an integrative account, which allows for different neural response patterns depending on the amount of neuronal damage and the recruitment of compensatory pathways.
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Affiliation(s)
- David Prvulovic
- Laboratory for Neurophysiology and Neuroimaging, Department of Psychiatry, Johann Wolfgang Goethe-Universität, Heinrich-Hoffmann-Str. 10, 60528 Frankfurt, Germany.
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Moritz CH, Johnson SC, McMillan KM, Haughton VM, Meyerand ME. Functional MRI neuroanatomic correlates of the Hooper Visual Organization Test. J Int Neuropsychol Soc 2004; 10:939-47. [PMID: 15803557 DOI: 10.1017/s1355617704107042] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The Hooper Visual Organization Test (VOT), a commonly applied neuropsychological test of visual spatial ability, is used for assessing patients with suspected right hemisphere, or parietal lobe involvement. A controversy has developed over whether the inferences of this test metric can be assumed to involve global, lateralized, or regional functionality. In this study, the characteristic visual organization and object naming aspects of the VOT task presentation were adapted to a functional MR imaging (fMRI) paradigm to probe the neuroanatomic correlates of this neuropsychological test. Whole brain fMRI mapping results are reported on a cohort of normal subjects. Bilateral fMRI responses were found predominantly in the posterior brain, in regions of superior parietal lobules, ventral temporal-occipital cortex, and posterior visual association areas, and to a lesser extent, the frontal eye fields bilaterally, and left dorsolateral prefrontal cortex. The results indicate a general brain region or network in which VOT impairment, due to its visuospatial and object identification demands, is possible to be detected. Discussion is made of interpretive limitations when adapting neuropsychological tests to fMRI analysis.
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Affiliation(s)
- Chad H Moritz
- Department of Radiology, University of Wisconsin Medical School, Madison, USA.
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