The role of Brain Connectivity is going to be very crucial and influential in the field of neuroscience and medicine over the coming years. As impairment of structural and functional connectivity, either as a primary or secondary event, is implicated in neuronal damage in most brain disorders, Brain Connectivity plays a major role in research into normal brain function and a range of brain disorders. Because the field of neuroscience is constantly evolving, with multimodal imaging now considered to be the preferable method of evaluating different diseases and interventions, we have expanded the remit of Brain Connectivity to ensure that we are able to include articles of a translational nature while maintaining the core of Brain Connectivity with outstanding methodological contributions.
With the view toward expanding the scope of Brain Connectivity, I would like to invite original articles and reviews describing
The underlying mechanisms and influences on structural and functional connectivity behind neurological disease;
How different pathological substrates influence structural and functional connectivity in brain disorders;
Multimodal imaging in brain disorders in both human and animal models;
Experimental techniques combining magnetic resonance imaging (MRI) (connectivity), electroencephalography, magnetoencephalography, positron emission tomography, single photon emission computed tomography, and other new and evolving methods.
Original manuscripts, communications, and review articles are welcomed. Several subcategories under original articles and communications will be considered, including reports of original experimental data, methodological studies, novel data analysis schemes, theoretical data modeling, and descriptions of changes in brain connectivity in health and disease. We also welcome reports of original investigations in the areas of neuroscience, neurology, physics, biophysics, computer science, neuroinformatics, developmental biology, genetics, molecular biology, psychiatry, pharmacology, and anesthesiology, all of which influence brain connectivity.
In this issue you will find several high-quality articles by experts in their fields:
Bipolar Disorder and Gender Are Associated with Frontolimbic and Basal Ganglia Dysconnectivity: A Study of Topological Variance Using Network Analysis. In this study, Leila Nabulsi and Dara Cannon investigated topological patterns in bipolar disorder with the anatomically improved precision conferred by combining subject-specific parcellation/segmentation with non-tensor-based tractograms derived using a high angular resolution diffusion-weighted approach to understand the arrangement and connections of limbic regions with other functionally specialized cortico-subcortical subnetworks. They demonstrated that patients with bipolar disorder demonstrated impairments across whole-brain topological arrangements (density, degree, and efficiency), and a disconnected subnetwork involving limbic and basal ganglia relative to controls.
New Graph-Theoretical-Multimodal Approach Using Temporal and Structural Correlations Reveals Disruption in the Thalamo-Cortical Network in Patients with Schizophrenia. In this study, Paolo Finotelli and Simone Kuhn applied a new flexible graph-theoretical-multimodal model called FD (F, the functional connectivity matrix, and D, the structural matrix) to construct brain networks combining functional, structural and topological information of MRI measurements (structural and resting state imaging) to patients with schizophrenia and matched healthy individuals and compared this with the traditional pure functional connectivity (pFC) analysis. They found disrupted connectivity in the thalamo-cortical network in schizophrenic patients using the FD model, whereas the traditional pFC model failed to extract group differences after correction for multiple comparison implying that the FD model is superior.
Longer Transcranial Magnetic Stimulation Intertrial Interval Increases Size, Reduces Variability, and Improves the Reliability of Motor Evoked Potentials. In this study, Maryam Hassanzahraee and Shapour Jaberzadeh from Monash University, Melbourne, Australia, investigated the effects of different inter-trial intervals (ITIs) of single-pulse transcranial magnetic stimulation on the amplitude, variability, and test–retest reliability of the motor evoked potential (MEP). This study revealed significantly larger MEP amplitudes following ITI 10, 15, 20s compared to ITI 5 with no significant increases between ITI 15 and 20s. Standardized z-value SDs revealed variability rate reduction following longer ITI with significant reductions occurring following inter-trial intervals of 10, 15, and 20 seconds compared with an inter-trial interval of 5 seconds with no significant difference between 15 and 20 seconds, indicating that a longer inter-trial interval up to 15 seconds can significantly induce larger motor evoked potential with lower variability and higher reliability.
Brain Development Includes Linear and Multiple Nonlinear Trajectories: A Cross-Sectional Resting-State Functional Magnetic Resonance Imaging Study. In this study, Ashkan Faghiria and Vince D. Calhouna from University of New Mexico used the cross-sectional resting state functional MRI data of 368 subjects, aged 3 to 21 years, to examine the linear and nonlinear development of brain connectivity using a clustering approach to characterize the developmental patterns into different linear and nonlinear groups. They demonstrated that functional brain development exhibits multiple types of linear and nonlinear patterns and caution against the assumption that brain connectivity values reach a stable state after a specific age.
Finally, as we are preparing for the holiday season and the new year, I would like to thank all the staff who are tirelessly working behind the scenes at Brain Connectivity to ensure that this knowledge is propagated widely around the world. I would also like to thank all the authors who have contributed to the journal over the years, and all the associate editors and the entire editorial board for their generous contribution to the journal. Wishing you all very happy holidays and a prosperous new year.
