Open Neuroimaging Journal最新文献

{"title":"High-Frequency Time-Resolved Scanning Acoustic Microscopy for Biomedical Applications","authors":"P. Anastasiadis, P. Zinin","doi":"10.2174/1874440001812010069","DOIUrl":"https://doi.org/10.2174/1874440001812010069","url":null,"abstract":"High-frequency focused ultrasound has emerged as a powerful modality for both biomedical imaging and elastography. It is gaining more attention due to its capability to outperform many other imaging modalities at a submicron resolution. Besides imaging, high-frequency ultrasound or acoustic biomicroscopy has been used in a wide range of applications to assess the elastic and mechanical properties at the tissue and single cell level. The interest in acoustic microscopy stems from the awareness of the relationship between biomechanical and the underlying biochemical processes in cells and the vast impact these interactions have on the onset and progression of disease. Furthermore, ultrasound biomicroscopy is characterized by its non-invasive and non-destructive approach. This, in turn, allows for spatiotemporal studies of dynamic processes without the employment of histochemistry that can compromise the integrity of the samples. Numerous techniques have been developed in the field of acoustic microscopy. This review paper discusses high-frequency ultrasound theory and applications for both imaging and elastography.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2018-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47906645","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Manganese-enhanced MRI Offers Correlation with Severity of Spinal Cord Injury in Experimental Models","authors":"N. Martirosyan, G. Turner, J. Kaufman, Arpan A. Patel, E. Belykh, M. Kalani, N. Theodore, M. Preul","doi":"10.2174/1874440001610010139","DOIUrl":"https://doi.org/10.2174/1874440001610010139","url":null,"abstract":"Background: Spinal cord injuries (SCI) are clinically challenging, because neural regeneration after cord damage is unknown. In SCI animal models, regeneration is evaluated histologically, requiring animal sacrifice. Noninvasive techniques are needed to detect longitudinal SCI changes. Objective: To compare manganese-enhanced magnetic resonance imaging (MRI [MEMRI]) in hemisection and transection of SCI rat models with diffusion tensor imaging (DTI) and histology. Methods: Rats underwent T9 spinal cord transection (n=6), hemisection (n=6), or laminectomy without SCI (controls, n=6). One-half of each group received lateral ventricle MnCl2 injections 24 hours later. Conventional DTI or T1-weighted MRI was performed 84 hours post-surgery. MEMRI signal intensity ratio above and below the SCI level was calculated. Fractional anisotropy (FA) measurements were taken 1 cm rostral to the SCI. The percentage of FA change was calculated 10 mm rostral to the SCI epicenter, between FA at the dorsal column lesion normalized to a lateral area without FA change. Myelin load (percentage difference) among groups was analyzed by histology. Results: In transection and hemisection groups, mean MEMRI ratios were 0.62 and 0.87, respectively, versus 0.99 in controls (P<0.001 and P<0.001, respectively); mean FA decreases were 67.5% and 40.1%, respectively, compared with a 6.1% increase in controls (P=0.002 and P=0.019, respectively). Mean myelin load decreased by 38.8% (transection) and 51.8% (hemisection) compared to controls (99.1%) (P<0.001 and P<0.001, respectively). Pearson’s correlation coefficients were -0.94 for MEMRI ratio and FA changes and 0.87 for MEMRI and myelin load. Conclusion: MEMERI results correlated to SCI severity measured by FA and myelin load. MEMRI is a useful noninvasive tool to assess neuronal damage after SCI.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"139 - 147"},"PeriodicalIF":0.0,"publicationDate":"2016-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68073915","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Putamen Activation Represents an Intrinsic Positive Prediction Error Signal for Visual Search in Repeated Configurations","authors":"S. Sommer, S. Pollmann","doi":"10.2174/1874440001610010126","DOIUrl":"https://doi.org/10.2174/1874440001610010126","url":null,"abstract":"We investigated fMRI responses to visual search targets appearing at locations that were predicted by the search context. Based on previous work in visual category learning we expected an intrinsic reward prediction error signal in the putamen whenever the target appeared at a location that was predicted with some degree of uncertainty. Comparing target appearance at locations predicted with 50% probability to either locations predicted with 100% probability or unpredicted locations, increased activation was observed in left posterior putamen and adjacent left posterior insula. Thus, our hypothesis of an intrinsic prediction error-like signal was confirmed. This extends the observation of intrinsic prediction error-like signals, driven by intrinsic rather than extrinsic reward, to memory-driven visual search.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"126 - 138"},"PeriodicalIF":0.0,"publicationDate":"2016-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68073906","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Neuroimaging Genetics Edited by Bigos et al. Oxford University Press","authors":"K. Mathiak, M. Klasen","doi":"10.2174/1874440001610010125","DOIUrl":"https://doi.org/10.2174/1874440001610010125","url":null,"abstract":"Over the last two decades, the association of genetic variation and brain function has received considerable attention. It is well established that most psychiatric and neurological diseases have a substantial genetic contribution. Therefore, investigating the influences of genotypes on brain structure and function should lead to a better understanding of the neurobiology of physiological brain functions and neuropsychiatric disorders. Neuroimaging Genetics - Principles and Practices is a comprehensive volume which exhaustively covers this field of imaging genetics. The table of contributors is a who-is-who of top-ranking researchers in the field, and the scientific quality of the single chapters is extraordinary. The book offers an impressive range of thematic fields, spanning from basic neuroscience to clinical implications. Most of the topics are covered with stunning detail, including basically all relevant studies on the respective issue. This makes the volume an important reference book for experienced researchers of the neuroimaging genetics community. Beginners, however, may miss a broader introduction to basic concepts concerning the molecular biology as well as the imaging techniques. Methodological overviews in future editions may render the book more accessible to less specialized readers. In a similar vein, more figures may help to illustrate the content of the text better and help to get a faster insight into the topics.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"125 - 125"},"PeriodicalIF":0.0,"publicationDate":"2016-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68074437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the Neurocircuitry Underpinning Predictability of Threat in Soldiers with PTSD Compared to Deployment Exposed Controls.","authors":"Michael N Dretsch, Kimberly H Wood, Thomas A Daniel, Jeffrey S Katz, Gopikrishna Deshpande, Adam M Goodman, Muriah D Wheelock, Kayli B Wood, Thomas S Denney, Stephanie Traynham, David C Knight","doi":"10.2174/1874440001610010111","DOIUrl":"10.2174/1874440001610010111","url":null,"abstract":"<p><strong>Background: </strong>Prior work examining emotional dysregulation observed in posttraumatic stress disorder (PTSD) has primarily been limited to fear-learning processes specific to anticipation, habituation, and extinction of threat. In contrast, the response to threat itself has not been systematically evaluated.</p><p><strong>Objective: </strong>To explore potential disruption in fear conditioning neurocircuitry in service members with PTSD, specifically in response to predictable <i>versus</i> unpredictable threats.</p><p><strong>Method: </strong>In the current study, active-duty U.S. Army soldiers with (PTSD group; <i>n</i> = 38) and without PTSD (deployment-exposed controls; DEC; <i>n</i> = 40), participated in a fear-conditioning study in which threat predictability was manipulated by presenting an aversive unconditioned stimulus (UCS) that was either preceded by a conditioned stimulus (<i>i.e.</i>, predictable) or UCS alone (<i>i.e.</i>, unpredictable). Threat expectation, skin conductance response (SCR), and functional magnetic resonance imaging (fMRI) signal to predictable and unpredictable threats (<i>i.e.</i>, UCS) were assessed.</p><p><strong>Results: </strong>Both groups showed greater threat expectancy and diminished threat-elicited SCRs to predictable compared to unpredictable threat. Significant group differences were observed within the amygdala, hippocampus, insula, and superior and middle temporal gyri. Contrary to our predictions, the PTSD group showed a diminished threat-related response within each of these brain regions during predictable compared to unpredictable threat, whereas the DEC group showed increased activation.</p><p><strong>Conclusion: </strong>Although, the PTSD group showed greater threat-related diminution, hypersensitivity to unpredictable threat cannot be ruled out. Furthermore, pre-trauma, trait-like factors may have contributed to group differences in activation of the neurocircuitry underpinning fear conditioning.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"111-124"},"PeriodicalIF":0.0,"publicationDate":"2016-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5101630/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68074394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Attentional Networks in Adolescents with High-functioning Autism: An fMRI Investigation","authors":"E. Hames, R. Rajmohan, Dan Fang, Ron Anderson, M. Baker, D. Richman, M. O'Boyle","doi":"10.2174/1874440001610010102","DOIUrl":"https://doi.org/10.2174/1874440001610010102","url":null,"abstract":"Background: Attentional deficits in Autism spectrum disorder (ASD) are often noted, but their specific nature remains unclear. Objective: The present study used the child Attentional Network Task (Child ANT) in combination with functional magnetic resonance imaging (fMRI) to determine if the consistently cited deficits of orienting attention are truly due to dysfunctions of orienting-based networks. We hypothesized that these observations are, in fact, a reflection of executive dysfunctions. As such, we expected that although ASD adolescents would perform worse on the orienting portion of the Child ANT, the strongest differences in activation between them and the neurotypical (NT) control group would be in areas classically associated with executive functioning (e.g., the frontal gyri and anterior cingulate cortex). Method: The brain activity of six high-functioning adolescents with ASD and six NT adolescents was recorded while these individuals performed the three subcomponents of the Child ANT. Results: ASDs were shown to be more accurate than NTs for the alerting, less accurate for the orienting, and similar in accuracy for the executive portions of the Child ANT. fMRI data showed increased bilateral frontal gyri recruitment, areas conventionally associated with executive control, during the orienting task for the ASD group. Conclusion: We submit that the increased activations represent neurocorrelates of signal fixation attributable to the subset of executive control responsible for sustained maintenance signals, not the main components of orienting. Therefore, excessive fixation in ASD adolescents is likely due to dysfunctions of executive control and not the orienting subcomponent of the attention network.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"102 - 110"},"PeriodicalIF":0.0,"publicationDate":"2016-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2174/1874440001610010102","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68074381","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sex Differences in Gamma Band Functional Connectivity Between the Frontal Lobe and Cortical Areas During an Auditory Oddball Task, as Revealed by Imaginary Coherence Assessment","authors":"T. Fujimoto, E. Okumura, A. Kodabashi, K. Takeuchi, T. Otsubo, Katsumi Nakamura, K. Yatsushiro, M. Sekine, Shinichiro Kamiya, S. Shimooki, T. Tamura","doi":"10.2174/1874440001610010085","DOIUrl":"https://doi.org/10.2174/1874440001610010085","url":null,"abstract":"We studied sex-related differences in gamma oscillation during an auditory oddball task, using magnetoencephalography and electroencephalography assessment of imaginary coherence (IC). We obtained a statistical source map of event-related desynchronization (ERD) / event-related synchronization (ERS), and compared females and males regarding ERD / ERS. Based on the results, we chose respectively seed regions for IC determinations in low (30-50 Hz), mid (50-100 Hz) and high gamma (100-150 Hz) bands. In males, ERD was increased in the left posterior cingulate cortex (CGp) at 500 ms in the low gamma band, and in the right caudal anterior cingulate cortex (cACC) at 125 ms in the mid-gamma band. ERS was increased in the left rostral anterior cingulate cortex (rACC) at 375 ms in the high gamma band. We chose the CGp, cACC and rACC as seeds, and examined IC between the seed and certain target regions using the IC map. IC changes depended on the height of the gamma frequency and the time window in the gamma band. Although IC in the mid and high gamma bands did not show sex-specific differences, IC at 30-50 Hz in males was increased between the left rACC and the frontal, orbitofrontal, inferior temporal and fusiform target regions. Increased IC in males suggested that males may acomplish the task constructively, analysingly, emotionally, and by perfoming analysis, and that information processing was more complicated in the cortico-cortical circuit. On the other hand, females showed few differences in IC. Females planned the task with general attention and economical well-balanced processing, which was explained by the higher overall functional cortical connectivity. CGp, cACC and rACC were involved in sex differences in information processing and were likely related to differences in neuroanatomy, hormones and neurotransmitter systems.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"85 - 101"},"PeriodicalIF":0.0,"publicationDate":"2016-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2174/1874440001610010085","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68074369","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Does Congenital Deafness Affect the Structural and Functional Architecture of Primary Visual Cortex?","authors":"C. R. Smittenaar, M. MacSweeney, M. Sereno, D. S. Schwarzkopf","doi":"10.2174/1874440001610010001","DOIUrl":"https://doi.org/10.2174/1874440001610010001","url":null,"abstract":"Deafness results in greater reliance on the remaining senses. It is unknown whether the cortical architecture of the intact senses is optimized to compensate for lost input. Here we performed widefield population receptive field (pRF) mapping of primary visual cortex (V1) with functional magnetic resonance imaging (fMRI) in hearing and congenitally deaf participants, all of whom had learnt sign language after the age of 10 years. We found larger pRFs encoding the peripheral visual field of deaf compared to hearing participants. This was likely driven by larger facilitatory center zones of the pRF profile concentrated in the near and far periphery in the deaf group. pRF density was comparable between groups, indicating pRFs overlapped more in the deaf group. This could suggest that a coarse coding strategy underlies enhanced peripheral visual skills in deaf people. Cortical thickness was also decreased in V1 in the deaf group. These findings suggest deafness causes structural and functional plasticity at the earliest stages of visual cortex.","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"10 1","pages":"1 - 19"},"PeriodicalIF":0.0,"publicationDate":"2016-02-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.2174/1874440001610010001","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68074234","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"CASE REPORT: MENINGIOMA WITH INTRA-TUMOURAL HAEMORRHAGE SECONDARY TO RUPTURED DISTAL ANTERIOR CEREBRAL ARTERY ANEURYSM","authors":"","doi":"10.2174/1874440001307010035","DOIUrl":"https://doi.org/10.2174/1874440001307010035","url":null,"abstract":"","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":"7 1","pages":"35 - 35"},"PeriodicalIF":0.0,"publicationDate":"2013-12-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68074219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Combining graph and machine learning methods to analyze differences in functional connectivity across sex.","authors":"R Casanova,&nbsp;C T Whitlow,&nbsp;B Wagner,&nbsp;M A Espeland,&nbsp;J A Maldjian","doi":"10.2174/1874440001206010001","DOIUrl":"https://doi.org/10.2174/1874440001206010001","url":null,"abstract":"<p><p>In this work we combine machine learning methods and graph theoretical analysis to investigate gender associated differences in resting state brain network connectivity. The set of all correlations computed from the fMRI resting state data is used as input features for classification. Two ensemble learning methods are used to perform the detection of the set of discriminative edges between groups (males vs. females) of brain networks: 1) Random Forest and 2) an ensemble method based on least angle shrinkage and selection operator (lasso) regressors. Permutation testing is used not only to assess significance of classification accuracy but also to evaluate significance of feature selection. Finally, these methods are applied to data downloaded from the Connectome Project website. Our results suggest that gender differences in brain function may be related to sexually dimorphic regional connectivity between specific critical nodes via gender-discriminative edges.</p>","PeriodicalId":37431,"journal":{"name":"Open Neuroimaging Journal","volume":" ","pages":"1-9"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ftp.ncbi.nlm.nih.gov/pub/pmc/oa_pdf/49/51/TONIJ-6-1.PMC3271304.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"39967794","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}