OBJECTIVETo explore the pathophysiological changes in the functional connectivity of posterior cingulate cortex (PCC) with other brain regions in children with attention-deficit or hyperactivity disorder (ADHD) on resting-state functional magnetic resonance imaging(fMRI) and explore the neural mechanisms of ADHD at the point of relationships between brain regions.METHODSThirty children with ADHD from the Third Affiliated Hospital of Soochow University from June 2008 to April 2010 and another 30 age-and-gender-matched controls from a normal primary school over the same period underwent resting-state fMRI scans. And blood oxygenation level dependent (BOLD) signal was acquired to calculate the functional connectivity of PCC with other brain regions controls. Significant differences of connectivity between groups were analyzed with REST software.RESULTSThe pattern of functional connectivity of PCC for the ADHD group was similar to that of the control group. Significant positive functional connectivity with PCC was observed in the default mode of network (DMN) while negative functional connectivity was present in dorsolateral prefrontal cortex, anterior cingulate, parietal cortex and basal ganglia(all P < 0.05, corrected). Compared to the controls, the ADHD group exhibited decreased positive connectivity with PCC in bilateral medial prefrontal cortex (0.07 ± 0.20 vs 0.33 ± 0.23, t = -5.47), right posterior cingulate gyrus(0.25 ± 0.28 vs 0.48 ± 0.30, t = -3.44), right inferior temporal gyrus (-0.05 ± 0.19 vs 0.22 ± 0.22, t = -4.61) and cerebellar posterior lobe (-0.04 ± 0.21 vs 0.17 ± 0.16, t = -3.99), while decreased negative functional connectivity with PCC was observed in left insula (-0.10 ± 0.26 vs -0.30 ± 0.19, t = 3.71), right inferior parietal lobule (0.02 ± 0.18 vs -0.23 ± 0.17, t = 5.20), left postcentral gyrus (0.08 ± 0.26 vs -0.17 ± 0.25, t = 4.06), left superior temporal gyrus (-0.04 ± 0.25 vs -0.27 ± 0.17, t = 4.27), right superior temporal gyrus (-0.08 ± 0.25 vs -0.31 ± 0.21, t = 3.80) and left fusiform gyrus (-0.01 ± 0.25 vs -0.18 ± 0.17, t = 3.57)(all P < 0.05, corrected).CONCLUSIONSThe connectivity of DMN between brain regions is abnormal in ADHD group. And the strengthen of negative relationship between DMN and task activated network becomes reduced. It is surmised that the decreased internal synchronization of default network and disrupted balance between DMN and prefrontal-parietal attentional networks may be important neural mechanisms of ADHD.

Objective To explore the behavior and initial sandtray characters of the children with oppositional defiant disorders (ODD) in order to provide psychological and behavioral intervention as early as possible.Methods The differences of the Conners parent symptom questionnaire (PSQ) and initial sandtrays between 24 children with ODD and 24 normal children were compared.Results PSQ indicated that children with ODD had higher scores of conduct proble((1.31 ± 0.53),(0.36 ± 0.31)),learning problem ((2.01 ± 0.66),(0.57 ±0.5)),hyperactivity-impulsion ((1.60 ± 0.77),(0.35 ± 0.41)),anxiety ((0.60 ± 0.50),(0.27 ± 0.25)) and hyperactivity index((1.12 ± 0.31),(0.78 ± 0.28)) than normal children.On the use of toys,the experimental group was significantly higher in armament and transports and lower in plants and stones(P＜0.05).On the theme of sandtrays,the ODD group was significantly higher in disorder,neglect,injury,threat and lower in integration and energy (P ＜ 0.05).Conclusion The results show that the children with ODD have more anxiety experience than normal children and this may be associated with oppositional conduct.Children with ODD use more aggressive toys and wounded themes,revealing their attack and conflict.Psychological intervention can be provided according to the characters of behavior scale and initial sandtray.

Objective To exanfined differences of conflict monitor function between the inattentive and combined Attention deficit hyperactivity disorder(ADHD) subtypes using event-related potentials(ERP) to assess the degree of cognitive impairment and explore neural mechanisms.Methods ERPs elicited by performing the spatial Simon-Stroop task were recorded in 50 children with ADHD(ADHD/Inattentive,ADHD-Ⅰ(n =25) ;ADHD/Combined,ADHD-Ⅲ(n =25) and 30 normal children.The differences of N2 component of ERP results in three groups were compared and analysed.Results ①Amplitude:ERP data indicated that the amplitude of N2 of the children with ADHD-Ⅰ and ADHD-Ⅲ in Simon-incongruent trials (Siin (-4.33 ± 2.89) μV,(-2.49 ± 2.01)μV) and Stroop-inconsistent trials(Stin(-5.03 ± 3.03) μV,(-3.33 ± 1.44) μV) were lower than matched controls (Siin(-6.13 ± 2.93) μV; Stin (-6.58 ± 2.80) μV).ADHD-Ⅲ children were lower than ADHD-Ⅰ children,and the difference had statistic significance (P ＜ 0.05).②Latency:the latency of both subtypes of ADHD were longer than controls in Siin(ADHD-Ⅰ (339.80 ± 31.96) ms,ADHD-Ⅲ(358.70 ± 22.10) ms,control(325.96 ± 23.01) ms) and Stin(ADHD-Ⅰ (344.29 ± 26.23) ms,ADHD-Ⅲ(352.60 ± 17.90) ms,control(331.15 ± 24.62)ms) condition,the difference had statistic significance (P ＜ 0.05),ADHD-I children were shorter than ADHD-Ⅲ children in Siin and Stin condition,but only in Siin condition the difference had statistic significance(P ＜ 0.05).Conclusion Conflict monitoring function defect of ADHD-Ⅲ are more serious than ADHD-Ⅰ,the ability of identify task relevant stimulus dimensions and resist irrelevant stiuutus dimensions or automatic response to task-related stimulus was weaker.The neural mechanisms and congnitive of two subtypes may be different.

Objective To investigate the correlation of spontaneous brain activity and Go/Nogo task performance with fractional amplitude of low-frequency fluctuation (fALFF)of the resting-state fMRI,and explore the functional basis of response inhibition.Methods Twenty-four college students were experienced resting-sate fMRI scans and Go/Nogo task and blood oxygenation level dependent (BOLD) signal and task behavioral performance were acquired to calculate the fractional amplitude of low-frequency fluctuation (fALFF)and intra-individual coefficient of variation(ICV).Pearson's correlation analysis between the fALFF values and the ICV was performed in a voxel-wise manner to get the significant fALFF-ICV correlation map(corrected,P ＜ 0.05).Results Significant negative fALFF-ICV correlations were observed in right gyrus rectus(BA11,r =-0.66),right superior frontal gyrus(BA10,r =-0.82),left mediate frontal(BA10,r =-0.80),left inferior frontal gyrus (BA45,r =-0.78),right inferior parietal lobule(BA2,r =-0.78),left supplementary motor area(BA6,r =-0.70) and right cerebellum(r=-0.63).Significant positive fALFF-ICV correlations were observed in bilateral cuneus gyrus(BA18/19,r =0.68),left middle occipital cortex (BA19,r =0.73),left inferior occipital cortex (BA19,r =0.76) and bilateral lingual gyrus(BA17,r=0.77).Conclusion Close correlations between resting-state brain activities and Go/Nogo task performance are observed in the frontal cortex,supplementary motor area,posterior occipital lobe,cerebellum and some DMN regions.It is indicated that prefrontal cortex may have important influence on the efficiency of response inhibition,meanwhile,the default mode network may have possible influence on the efficiency of task performance.