Structural Asymmetry of Dorsolateral Prefrontal Cortex Correlates with Depressive Symptoms： Evidence from Healthy Individuals and Patients with Major Depressive Disorder

In this study,we investigated the role of structural asymmetry of the dorsolateral prefrontal cortex（DLPFC） in the continuum of depression from healthy individuals to patients.Structural magnetic resonance imaging was performed in 70 patients with major depressive disorder（MDD）,49 matched controls,and 349 healthy university students to calculate structural asymmetry indexes of the DLPFC.First-episode,treatment-naive MDD patients showed a relatively lower asymmetry index than healthy controls,and their asymmetry index was negatively correlated with the depressive symptoms.This abnormality was normalized by antidepressants in medicated MDD patients.Furthermore,the asymmetry index was negatively correlated with the depressive symptoms in university students;this was replicated at two time points in a subgroup of students,suggesting good test-retest reliability.Our findings are consistent with previous studiesthat support the imbalance hypothesis of MDD and suggest a potential structural basis underlying the functional asymmetry of the DLPFC in depression.In future,the structural index of the DLPFC may become a potential biomarker to evaluate individuals＇ risk for the onset of MDD.

Mapping Domain- and Age-Specific Functional Brain Activity for Children’s Cognitive and Affective Development

The human brain undergoes rapid development during childhood,with significant improvement in a wide spectrum of cognitive and affective functions.Mapping domain-and age-specific brain activity patterns has important implications for characterizing the development of children’s cognitive and affective functions.The current mainstay of brain templates is primarily derived from structural magnetic resonance imaging(MRI),and thus is not ideal for mapping children’s cognitive and affective brain development.By integrating task-dependent functional MRI data from a large sample of 250 children(aged 7 to 12)across multiple domains and the latest easy-to-use and transparent preprocessing workflow,we here created a set of age-specific brain functional activity maps across four domains:attention,executive function,emotion,and risky decision-making.Moreover,we developed a toolbox named Developmental Brain Functional Activity maps across multiple domains that enables researchers to visualize and download domain-and age-specific brain activity maps for various needs.This toolbox and maps have been released on the Neuroimaging Informatics Tools and Resources Clearinghouse website(http://www.nitrc.org/projects/dbfa).Our study provides domain-and age-specific brain activity maps for future developmental neuroimaging studies in both healthy and clinical populations.

Examining brain structures associated with attention networks in a large sample of young adults: a voxel-based morphometry study

Attention networks have three principal components supported by separate subprocesses, which include alerting, orienting, and executive control(EC) networks.Efficiently and accurately extracting useful information from the environment as the function of attention is pivotal to our survival. Previous brain imaging studies have examined activation patterns underlying the different attention networks in different cortical regions, yet focal differences in brain structures related to attention network components were not well understood. Therefore, in this study, voxel-based morphometry was used to investigate the relationship between gray matter volume(GMV) and different attention networks in a large young adult sample(n = 156). As a result, multiple regression analysis revealed that higher alerting scores(stronger alerting ability) were negatively significantly correlated with region gray matter volume(r GMV) in the PCC/Pre Cu(posterior cingulate cortex/precuneus), which might be associated with continuous maintenance of a vigilant state. Then,lower EC scores(stronger conflict resolution ability) were associated with larger r GMV in the dorsal anterior cingulate cortex, which might be related to high-efficiency executive control processing. Together, findings of thepresent study provided a unique structural basis of GMV for individual differences in alerting and EC networks.

Suppression dampens unpleasant emotion faster than reappraisal:Neural dynamics in a Chinese sample

The timing dynamics of regulating negative emotion with expressive suppression and cognitive reappraisal were investigated in a Chinese sample. Event-Related Potentials were recorded while subjects were required to view, suppress emotion expression to, or reappraise emotional pictures. The results showed a similar reduction in self-reported negative emotion during both strategies. Additionally, expressive suppression elicited larger amplitudes than reappraisal in central-frontal P3 component(340–480 ms). More importantly, the Late Positive Potential(LPP) amplitudes were decreased in each 200 ms of the 800–1600 ms time intervals during suppression vs. viewing conditions. In contrast, LPP amplitudes were similar for reappraisal and viewing conditions in all the time windows, except for the decreased amplitudes during reappraisal in the 1400–1600 ms. The LPP(but not P3) amplitudes were positively related to negative mood ratings, whereas the amplitudes of P3, rather than LPP, predict self-reported expressive suppression. These results suggest that expressive suppression decreases emotion responding more rapidly than reappraisal, at the cost of greater cognitive resource involvements in Chinese individuals.

“Aha!” effects in a guessing Chinese logogriph task:An event-related potential study

In the present study,high-density event-related potentials(ERPs)were recorded to examine the elec-trophysiologic correlates of "Aha!" effects in a guessing Chinese logogriph task by using a two-stage model for learning-testing.Results showed that:Firstly Successful Guessing elicited a more negative ERP deflection(N350)than Recognition did in the time window from 300―350 ms after onset of the stimuli.A voltage map of the difference wave(Successful Guessing minus Recognition)showed strong activity at the front-central region.Dipole analysis localized the generator of the N350 in the vicinity of the posterior cingulate cortex(PCC)and the inferior frontal gyrus.Secondly,a greater late positive component(LPC)in Successful Guessing than Recognition was found between 600 and 700 ms post-stimulus.Dipole analysis localized the generator of LPC in the right parahippocampal gyrus.