Concordance among indices of intrinsic brain function： Insights from inter-individual variation and temporal dynamics

Various resting-state fMRI(R-fMRI) measures have been developed to characterize intrinsic brain activity. While each of these measures has gained a growing presence in the literature, questions remain regarding the common and unique aspects these indices capture. The present work provided a comprehensive examination of inter-individual variation and intra-individual temporal variation for commonly used measures, including fractional amplitude of low frequency fluctuations, regional homogeneity,voxel-mirrored homotopic connectivity, network centrality and global signal correlation. Regardless of whether examining intra-individual or inter-individual variation, we found that these definitionally distinct R-fMRI indices tend to exhibit a relatively high degree of covariation, which doesn't exist in phase randomized surrogate data. As a measure of intrinsic brain function, concordance for R-fMRI indices was negatively correlated with age across individuals(i.e., concordance among functional indices decreased with age). To understand the functional significance of concordance, we noted that higher concordance was generally associated with higher strengths of R-fMRI indices, regardless of whether looking through the lens of inter-individual(i.e., high vs. low concordance participants) or intra-individual(i.e., high vs.low concordance states identified via temporal dynamic analyses) differences. We also noted a linear increase in functional concordance together with the R-fMRI indices through the scan, which may suggest a decrease in arousal. The current study demonstrated an enriched picture regarding the relationship among the R-fMRI indices, as well as provided new insights in examining dynamic states within and between individuals.

Neuroimaging brain growth charts:A road to mental health

Mental disorders are common health concerns and contribute to a heavy global burden on our modern society.It is challenging to identify and treat them timely.Neuroimaging evidence suggests the incidence of various psychiatric and behavioral disorders is closely related to the atypical development of brain structure and function.The identification and understanding of atypical brain development provide chances for clinicians to detect mental disorders earlier,perhaps even prior to onset,and treat them more precisely.An invaluable and necessary method in identifying and monitoring atypical brain development are growth charts of typically developing individuals in the population.The brain growth charts can offer a series of standard references on typical neurodevelopment,representing an important resource for the scientific and medical communities.In the present paper,we review the relationship between mental disorders and atypical brain development from a perspective of normative brain development by surveying the recent progress in the development of brain growth charts,including four aspects on growth chart utility:1)cohorts,2)measures,3)mechanisms,and 4)clinical translations.In doing so,we seek to clarify the challenges and opportunities in charting brain growth,and to promote the application of brain growth charts in clinical practice.

Electro-tactile stimulation (ETS) enhances cochlear-implant Mandarin tone recognition

Objective:Electro-acoustic stimulation (EAS) is an effective method to enhance cochlear-implant performance in individuals who have residual low-frequency acoustic hearing.To help the majority of cochlear implant users who do not have any functional residual acoustic hearing,electro-tactile stimulation (ETS) may be used because tactile sensation has a frequency range and perceptual capabilities similar to that produced by acoustic stimulation in the EAS users.Methods:Following up the first ETS study showing enhanced English sentence recognition in noise,1 the present study evaluated the effect of ETS on Mandarin tone recognition in noise in two groups of adult Mandarin-speaking individuals.The first group included 11 normalhearing individuals who listened to a 4-channel,noise-vocoded,cochlear-implant simulation.The second group included 1 unilateral cochlear-implant user and 2 bilateral users with each of their devices being tested independently.Both groups participated in a 4-alternative,forced-choice task,in which they had to identify a tone that was presented in noise at a 0-dB signal-to-noise ratio via electric stimulation (actual or simulated cochlear implants),tactile stimulation or the combined ETS.Results:While electric or tactile stimulation alone produced similar tone recognition (～40％ correct),the ETS enhanced the cochlear-implant tone recognition by 17-18 percentage points.The size of the present ETS enhancement effect was similar to that of the previously reported EAS effect on Mandarin tone recognition.Psychophysical analysis on tactile sensation showed an important role of frequency discrimination in the ETS enhancement.Conclusion:Tactile stimulation can potentially enhance Mandarin tone recognition in cochlear-implant users who do not have usable residual acoustic hearing.To optimize this potential,high fundamental frequencies need to be transposed to a 100-200 Hz range.

Functional brain network mapping with dual regression

Functional magnetic resonance imaging（fMRI）is an in-vivo non-invasive technique for measuring brain activity with excellent spatial and good temporal resolution.Without performing explicit tasks,resting-state fMRI（rfMRI）is widely used to map the functional connectivity network（FCN）,which refers to a large-scale network of interdependent or functionally connected brain regions and it could be detected by using different algorithms（Zuo and Xing, 2014）.ciation CAS （2016084）, Guangxi Bagui Scholarship, the Natural Science Foundation of China （81471740, 81220108014）, the Major Project of National Social Science Foundation of China （14ZDB161）, Beijing Municipal Science and Tech Commission （Z161100002616023, Z161100000216152） and the National R＆D Infrastructure and Facility Development Program ＂Fundamental Science Data Sharing Platform＂ （DKA2017-12-02-21）.

Developmental population neuroscience: emerging from ICHBD

The 3rd International Conference on Human Brain Development(ICHBD)was held during October 10–15,2017 in Nanning,Guangxi,China.ICHBD was initiated in 2014 by Drs.Xi-Nian Zuo,Olaf Sporns and Michael P.Milham(co-chairs),and has been consistently supported by a major international collaboration grant from Natural Science Foundation of China(81220108014).The goal of ICHBD is to bring together international scientists from a