- Email: [email protected]
22-Effect of spatial smoothing on graph analysis of fMRI data
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Abstracts / Clinical Neurophysiology 129 (2018) e7–e13
and positive waves, with some fasciculations, were found. Motor unit potentials reflected the severity and duration of acute motoneuron disorder. doi:10.1016/j.clinph.2018.01.039
20-Combining non-invasive brain stimulation with MRI for modulation of large-scale brain networks—I. Rektorová (CEITEC MU, Masaryk University, Brno, Czech Republic) Non-invasive brain stimulation (NIBS) includes particularly repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation or transcranial alternating current stimulation using low electrical current of 1–2 mA (tDCS, tACS). Based on stimulation parameters rTMS and tDCS may enhance (>5 Hz TMS, anodal tDCS) or inhibit (<1 Hz TMS, cathodal tDCS) neuronal excitability when applied over the primary motor cortex. Other brain regions may be targeted using frameless stereotaxy for the coil navigation and effects of distinct stimulation protocols might vary based on functional brain status. The use of NIBS in neurodegenerative brain diseases is experimental and a high inter-subject variability exists in measurable aftereffects. Combining NIBS with other techniques such as MRI or EEG might help to identify optimal stimulation targets for specific patient groups in order to enhance distinct long-lasting behavioral aftereffects. Imaging or EEG might provide a readout for specific NIBSinduced behavioral aftereffects and identify optimal candidates for NIBS within studied patient cohorts. After the lecture the audience will understand principles of NIBS and will be able to describe multimodal approaches to optimize stimulation protocols with an aim to modulate brain plasticity and enhance function. doi:10.1016/j.clinph.2018.01.040
21-Brain network activity during reading and writing of Czech ˇ 1, I. Rektorová 1, S. Rapcsak 2 words and nonwords—M. Barton 1 2 ( CEITEC, Brno, Czech Republic, University of Arizona, Tucson, USA)
22-Effect of spatial smoothing on graph analysis of fMRI data— M. Gajdoš 1, M. Mikl 1, E. Vy´tvarová 2 (1 CEITEC MU, Brno, Czech Republic, 2 FI MU, Brno, Czech Republic) Introduction: Smoothing is used to increase SNR. Here we examine it’s effect of smoothing on graph analysis of fMRI data. Methods: We used fMRI data of 30 subjects from HCP (Human Connectome Project; 3T; motor task). We preprocessed the data using realign and unwarp, spatial normalization, filtering and smoothing with FWHM = {none, 3, 5, 8 and 11} mm, parcellated according AAL atlas, used mean and first eigenvector as representative signal. Finally, we performed graph analysis using average node strength, characteristic path length, lambda, efficiency, clustering coefficient, and gamma. Results: Increase of FWHM is related to increase of clustering coefficient, node strength and efficiency, and to decrease of path length. Gamma and lambda are relatively not influenced by size of FMWH kernel. With low FHWM or no smoothing and using mean is the node strength higher and path length shorter. Discussion: Increase of FWHM increases correlations in the network, i.e. weights in graph. Therefore node strength increases and characteristic path length decreases. Clustering coefficient also reflects increasing weights between neighboring nodes. Increase of correlation coefficients with higher FWHM is more prominent when using first eigenvector as representative signal. We recommend to smooth fMRI data consistently across study. doi:10.1016/j.clinph.2018.01.042
23-Prenatal stress, mood, and gray matter volume in young adulthood—K. Marecˇková 1, A. Klasnja 2, P. Bencurova 1, L. Andry´sková 3, M. Brázdil 1,4, T. Paus 2,5,6 (1 CEITEC, Masaryk University (MU), Brno, Czech Republic, 2 Rotman Research Institute, Baycrest, Toronto, Canada, 3 RECETOX, Faculty of Science, MU, Brno, Czech Republic, 4 St. Anne’s University Hospital, MU, Brno, Czech Republic, 5 University of Toronto, Toronto, Canada, 6 Child Mind Institute, New York, USA)
Introduction: We used fMRI to identify the neural networks involved in processing Czech words and nonwords during reading aloud and writing to dictation. Activation in language areas and domain-general networks - dorsal attention (DAN), frontotparietal control (FPC), and default mode network (DMN) - were compared. Methods: Twenty-five Czech native speakers performed block design tasks on 3T Siemens Prisma scanner. Forty words and forty nonwords were presented. Passive viewing of checkerboards and simple low-level motor condition were used as baselines. Results: For reading and spelling of words, we observed activation in the language network. During reading and spelling of nonwords, stronger activation of visual word-form area (VWFA), language regions and additional recruitment of DAN and FPC were observed. The deactivations in DMN were stronger for nonwords than for words in both tasks. Conclusion: Despite the fact that reading and spelling differ in sensory input and motor output, they both engage left-lateralized components of the language network implicated in orthographic (VWFA) and phonological processing. Nonwords are more difficult than real words and therefore produce stronger activation within the task positive regions and higher level of deactivations in DMN.
This study aimed to determine whether prenatal stress, measured by the number of stressful life events during the first 20 weeks of pregnancy, might relate to mood dysregulation and altered brain structure in young adulthood. Participants included 93 mother – offspring pairs from a community-based birth cohort from the Czech Republic (European Longitudinal Study of Pregnancy and Childhood; ELSPAC-CZ). MRI analyses focused on overall cortical gray matter (GM) volume and GM volume of cortical regions previously associated with major depression. Higher prenatal stress predicted more mood dysregulation, particularly higher anxiety, fatigue and anger, lower overall cortical GM volume (corrected for brain size) and lower GM volume in mid-dorsolateral frontal cortex, anterior cingulate cortex and precuneus in young adulthood. We observed no Prenatal Stress by Sex interactions for any of the above relationships. We conclude that prenatal stress is an important risk factor that relates to worse mood states and altered brain structure in young adulthood irrespective of sex. Our results point to the importance and long lasting effects of prenatal programming and suggest that offspring of mothers who went through substantial stress during pregnancy might benefit from early intervention that would reduce the odds of mental illness in later life.
doi:10.1016/j.clinph.2018.01.041
doi:10.1016/j.clinph.2018.01.043
Abstracts / Clinical Neurophysiology 129 (2018) e7–e13
and positive waves, with some fasciculations, were found. Motor unit potentials reflected the severity and duration of acute motoneuron disorder. doi:10.1016/j.clinph.2018.01.039
20-Combining non-invasive brain stimulation with MRI for modulation of large-scale brain networks—I. Rektorová (CEITEC MU, Masaryk University, Brno, Czech Republic) Non-invasive brain stimulation (NIBS) includes particularly repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation or transcranial alternating current stimulation using low electrical current of 1–2 mA (tDCS, tACS). Based on stimulation parameters rTMS and tDCS may enhance (>5 Hz TMS, anodal tDCS) or inhibit (<1 Hz TMS, cathodal tDCS) neuronal excitability when applied over the primary motor cortex. Other brain regions may be targeted using frameless stereotaxy for the coil navigation and effects of distinct stimulation protocols might vary based on functional brain status. The use of NIBS in neurodegenerative brain diseases is experimental and a high inter-subject variability exists in measurable aftereffects. Combining NIBS with other techniques such as MRI or EEG might help to identify optimal stimulation targets for specific patient groups in order to enhance distinct long-lasting behavioral aftereffects. Imaging or EEG might provide a readout for specific NIBSinduced behavioral aftereffects and identify optimal candidates for NIBS within studied patient cohorts. After the lecture the audience will understand principles of NIBS and will be able to describe multimodal approaches to optimize stimulation protocols with an aim to modulate brain plasticity and enhance function. doi:10.1016/j.clinph.2018.01.040
21-Brain network activity during reading and writing of Czech ˇ 1, I. Rektorová 1, S. Rapcsak 2 words and nonwords—M. Barton 1 2 ( CEITEC, Brno, Czech Republic, University of Arizona, Tucson, USA)
22-Effect of spatial smoothing on graph analysis of fMRI data— M. Gajdoš 1, M. Mikl 1, E. Vy´tvarová 2 (1 CEITEC MU, Brno, Czech Republic, 2 FI MU, Brno, Czech Republic) Introduction: Smoothing is used to increase SNR. Here we examine it’s effect of smoothing on graph analysis of fMRI data. Methods: We used fMRI data of 30 subjects from HCP (Human Connectome Project; 3T; motor task). We preprocessed the data using realign and unwarp, spatial normalization, filtering and smoothing with FWHM = {none, 3, 5, 8 and 11} mm, parcellated according AAL atlas, used mean and first eigenvector as representative signal. Finally, we performed graph analysis using average node strength, characteristic path length, lambda, efficiency, clustering coefficient, and gamma. Results: Increase of FWHM is related to increase of clustering coefficient, node strength and efficiency, and to decrease of path length. Gamma and lambda are relatively not influenced by size of FMWH kernel. With low FHWM or no smoothing and using mean is the node strength higher and path length shorter. Discussion: Increase of FWHM increases correlations in the network, i.e. weights in graph. Therefore node strength increases and characteristic path length decreases. Clustering coefficient also reflects increasing weights between neighboring nodes. Increase of correlation coefficients with higher FWHM is more prominent when using first eigenvector as representative signal. We recommend to smooth fMRI data consistently across study. doi:10.1016/j.clinph.2018.01.042
23-Prenatal stress, mood, and gray matter volume in young adulthood—K. Marecˇková 1, A. Klasnja 2, P. Bencurova 1, L. Andry´sková 3, M. Brázdil 1,4, T. Paus 2,5,6 (1 CEITEC, Masaryk University (MU), Brno, Czech Republic, 2 Rotman Research Institute, Baycrest, Toronto, Canada, 3 RECETOX, Faculty of Science, MU, Brno, Czech Republic, 4 St. Anne’s University Hospital, MU, Brno, Czech Republic, 5 University of Toronto, Toronto, Canada, 6 Child Mind Institute, New York, USA)
Introduction: We used fMRI to identify the neural networks involved in processing Czech words and nonwords during reading aloud and writing to dictation. Activation in language areas and domain-general networks - dorsal attention (DAN), frontotparietal control (FPC), and default mode network (DMN) - were compared. Methods: Twenty-five Czech native speakers performed block design tasks on 3T Siemens Prisma scanner. Forty words and forty nonwords were presented. Passive viewing of checkerboards and simple low-level motor condition were used as baselines. Results: For reading and spelling of words, we observed activation in the language network. During reading and spelling of nonwords, stronger activation of visual word-form area (VWFA), language regions and additional recruitment of DAN and FPC were observed. The deactivations in DMN were stronger for nonwords than for words in both tasks. Conclusion: Despite the fact that reading and spelling differ in sensory input and motor output, they both engage left-lateralized components of the language network implicated in orthographic (VWFA) and phonological processing. Nonwords are more difficult than real words and therefore produce stronger activation within the task positive regions and higher level of deactivations in DMN.
This study aimed to determine whether prenatal stress, measured by the number of stressful life events during the first 20 weeks of pregnancy, might relate to mood dysregulation and altered brain structure in young adulthood. Participants included 93 mother – offspring pairs from a community-based birth cohort from the Czech Republic (European Longitudinal Study of Pregnancy and Childhood; ELSPAC-CZ). MRI analyses focused on overall cortical gray matter (GM) volume and GM volume of cortical regions previously associated with major depression. Higher prenatal stress predicted more mood dysregulation, particularly higher anxiety, fatigue and anger, lower overall cortical GM volume (corrected for brain size) and lower GM volume in mid-dorsolateral frontal cortex, anterior cingulate cortex and precuneus in young adulthood. We observed no Prenatal Stress by Sex interactions for any of the above relationships. We conclude that prenatal stress is an important risk factor that relates to worse mood states and altered brain structure in young adulthood irrespective of sex. Our results point to the importance and long lasting effects of prenatal programming and suggest that offspring of mothers who went through substantial stress during pregnancy might benefit from early intervention that would reduce the odds of mental illness in later life.
doi:10.1016/j.clinph.2018.01.041
doi:10.1016/j.clinph.2018.01.043