Examinando por Autor "Li, Ling"

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Altered predictive contextual processing of emotional faces versus abstract stimuli in adults with Autism Spectrum Disorder
(ELSEVIER IRELAND LTD, 2019-04-13) Fogelson, Noa; Li, Ling; Díaz Brage, Pablo; Amatriain-Fernandez, Sandra; Valle-Inclán, Fernando
OBJECTIVES: We investigated the proposition that Autism Spectrum Disorder (ASD) is associated with predictive contextual processing deficits. METHODS: We recorded electroencephalography (EEG) in adults with ASD and controls during the performance of a predictive contextual processing task, using either triangles or emotional faces. Targets were preceded by either randomized sequences (R) or by sequences including a predictive sequence (P). RESULTS: ASD subjects showed an attenuated behavioral facilitation (P versus R) compared with controls (faces). P3b amplitudes of P, R and the predictive sequence (n-1) were attenuated in ASD compared with controls. However, the attenuation of n-1 was more pronounced during the processing of faces. Controls demonstrated shorter peak P3b latencies of P versus R, while this facilitation was absent in ASD subjects. ASD subjects demonstrated functional connectivity alterations during the processing of random (triangles and faces) and predicted targets (faces). These changes were associated with weaker, more randomised, functional connections between frontal and parietal regions in ASD. CONCLUSIONS: We found predictive contextual processing alterations in ASD, which were more pronounced during the processing of emotional faces compared with abstract stimuli. SIGNIFICANCE: We provide novel evidence for the proposition that ASD is associated with deficits of top-down predictions.
Evaluating the causal contribution of fronto-parietal cortices to the control of the bottom-up and top-down visual attention using fMRI-guided TMS
(Elsevier, 2020-02-12) Wang, Min; Yu, Banglei; Luo, Cimei; Fogelson, Noa; Zhang, Junjun; Jin, Zhenlan; Li, Ling
Previous studies demonstrate that frontal and parietal cortices are involved in bottom-up and top-down attentional processes. However, their respective contribution to these processes remains controversial. The purpose of the current study was to compare the causal contribution of frontal and parietal cortices to the control of bottom-up and top-down visual attention using functional magnetic resonance imaging (fMRI) and repetitive transcranial magnetic stimulation (rTMS). Subjects performed visual search for targets that were easy (pop-out) or difficult (non-pop-out) to distinguish from distractors. Three sites of interest were used, based on the individual fMRI activation during the performance of a search task: the right dorsolateral prefrontal cortex (rDLPFC), the right frontal eye field (rFEF) and the right superior parietal lobule (rSPL). Online rTMS stimulation, with the search onset, showed that relative to rTMS over the vertex, rTMS over the rDLPFC, the rFEF and the rSPL increased the search reaction time (RTs) in the non-pop-out condition. In comparison, no TMS effect was found in the pop-out condition. In addition, the search RT cost caused by the non-pop-out condition was larger after the rDLPFC-TMS compared to the vertex-TMS. The findings suggest that the frontal and parietal cortical regions are both involved in attentional processing during top-down visual search, and that the rDLPFC is causally related to the executive control of cognitive load increases between the pop-out and the non-pop-out search.
Functional connectivity abnormalities during processing of predictive stimuli in patients with major depressive disorder
(Elsevier, 2019-11-09) Fogelson, Noa; Díaz-Brage, Pablo; Li, Ling; Peled, Avi; Klein, Ehud
The study investigated the underlying mechanisms associated with the ability of patients with major depressive disorder (MDD) to utilize predictive contextual information in order to facilitate detection of predictable versus random targets. To this end we evaluated EEG event-related functional connectivity during the processing of predictive stimuli in MDD and control subjects. A target detection task was used where targets were either preceded by randomized sequences of standards, or by sequences that included a predictive sequence. Functional connectivity was evaluated using synchronization likelihood and graph theory. The cluster coefficient and local efficiency values were greater in MDD compared to controls, during the processing of the three stimuli consisting of the predictive sequence, in the beta frequency band, suggesting an increased structured network organization. These changes were associated with increased functional connectivity within frontal networks in MDD patients compared to controls. However, no significant functional connectivity group-changes were observed for target conditions or randomized standards. These findings suggest that MDD is associated with context-specific functional connectivity abnormalities during the processing of predictive stimuli.