conjunction analysis
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2021 ◽  
pp. 188-192
Author(s):  
Xianyou He ◽  
Wei Zhang

As one origin of Chinese characters, pictograph has a graphical structure based on its referent. Are the aesthetic qualities of the reference objects reflected in the neural processing of pictographs? In the study reviewed in this chapter, participants were scanned while making aesthetic judgments of pictographs and their referents. The conjunction analysis revealed the common involvement of the bilateral inferior occipital gyri and inferior frontal gyri, the right superior occipital gyrus, the left middle occipital gyrus, and the inferior orbitofrontal cortex for the aesthetic judgments of pictographs and object images referring to beautiful objects. Moreover, only the beautiful judgments for pictographs but not object images activated the motor areas, implying that an approach motivation was elicited during the aesthetic perception of novel pictographs. Results indicate that not only the object images, but also the corresponding pictographs arouse a sense of beauty that relies on common neural mechanisms during aesthetic judgments.


Author(s):  
H. Jiang ◽  
J. Liu ◽  
H. W. Cheng

The continually increased space debris have posed great impact risks to existing space systems and human space flight. Accurate knowledge of propagation errors of space debris orbit is essential for many types of uses, such as space surveillance network tasking, conjunction analysis etc. Unfortunately, propagation error is not available for a two-line element (TLE). In this paper, a new TLE uncertainty estimation method based on neural network model is proposed. Object properties, space environment and predicted time-span are considered as the input of the network, the propagation errors in the direction of downrange, normal and conormal are as the output of the network. In order to assure the chosen orbit for training is not stable, only debris and rocket bodies are used. The network's effciency is demonstrated with some objects with continuous TLE data. Overall, the method proves accurate, computationally fast, and robust, and is applicable to any object in the satellite catalogue, especially for those newly launched objects.


2021 ◽  
Author(s):  
Russell Poldrack

This chapter focuses on the experimental designs developed for neuroimaging studies. It examines the various forms of experimental design used for functional neuroimaging, with a particular emphasis on the role of these designs in constraining inferences, and presents a discussion on decomposability of the mental processes. The chapter provides detailed information on the subtraction method, including its core problems, advantages, and alternatives to the subtraction approach. It discusses conjunction analysis and several experimental designs, including factorial designs, parametric designs, and priming/adaptation designs.


2020 ◽  
Author(s):  
Benjamin Klugah-Brown ◽  
Chenyang Jiang ◽  
Elijah Agoalikum ◽  
Xinqi Zhou ◽  
Liye Zou ◽  
...  

Aim: To determine robust transdiagnostic brain structural markers for compulsivity by capitalizing on the increasing number of case-control studies examining gray matter alterations in substance use disorders (SUD) and obsessive-compulsive disorder (OCD). Design: Pre-registered voxel-based meta-analysis of grey matter volume (GMV) changes through seed-based d Mapping (SDM), follow-up functional, and network-level characterization of the identified transdiagnostic regions by means of co-activation and Granger Causality (GCA) analysis. Participants: Literature search resulted in 31 original VBM studies comparing SUD (n=1191, mean-age=40.03, SD=10.87) and 30 original studies comparing OCD (n=1293, mean-age=29.18, SD=10.34) patients with healthy controls (SUD: n=1585, mean-age=42.63, SD=14.27, OCD: n=1374, mean-age=28.97, SD=9.96). Measurements: Voxel-based meta-analysis within the individual disorders as well as conjunction analysis were employed to reveal common GMV alterations between SUDs and OCD. Meta-analytic coordinates and signed brain volumetric maps determining directed (reduced or increased) brain volumetric alterations between the disorder groups and controls served as the primary outcome. Meta-analytic results employed statistical significance thresholding (FWE<0.05). Findings: Separate meta-analysis demonstrated that SUD (cocaine, alcohol, and nicotine) as well as OCD patients exhibited widespread GMV reductions in frontocortical regions including prefrontal, cingulate, and insular regions. Conjunction analysis revealed that the left inferior frontal gyrus (IFG) consistently exhibited decreased GMV across all disorders. Functional characterization suggests that the IFG represents a core hub in the cognitive control network and exhibits bidirectional (Granger) causal interactions with the striatum. Only OCD showed increased GMV in the dorsal striatum with higher changes being associated with more severe OCD symptomatology. Conclusions: Findings demonstrate robustly decreased GMV across the disorders in the left IFG, suggesting a transdiagnostic brain structural marker. The functional characterization as a key hub in the cognitive control network and casual interactions with the striatum suggest that deficits in inhibitory control mechanisms may promote compulsivity and loss of control that characterize both disorders.


2020 ◽  
Author(s):  
Junhai Xu ◽  
Haibin Dong ◽  
Fei Guo ◽  
Zeyu Wang ◽  
Jianguo Wei ◽  
...  

AbstractBeing able to accurately perceive the emotion expressed by the facial or verbal expression from others is critical to successful social interaction. However, only few studies examined the multimodal interactions on speech emotion, and there is no consistence in studies on the speech emotion perception. It remains unclear, how the speech emotion of different valence is perceived on the multimodal stimuli by our human brain. In this paper, we conducted a functional magnetic resonance imaging (fMRI) study with an event-related design, using dynamic facial expressions and emotional speech stimuli to express different emotions, in order to explore the perception mechanism of speech emotion in audio-visual modality. The representational similarity analysis (RSA), whole-brain searchlight analysis, and conjunction analysis of emotion were used to interpret the representation of speech emotion in different aspects. Significantly, a weighted RSA approach was creatively proposed to evaluate the contribution of each candidate model to the best fitted model. The results of weighted RSA indicated that the fitted models were superior to all candidate models and the weights could be used to explain the representation of ROIs. The bilateral amygdala has been shown to be associated with the processing of both positive and negative emotions except neutral emotion. It is indicated that the left posterior insula and the left anterior superior temporal gyrus (STG) play important roles in the perception of multimodal speech emotion.


2020 ◽  
Author(s):  
I Sarigiannidis ◽  
K Kieslich ◽  
C Grillon ◽  
M Ernst ◽  
JP Roiser ◽  
...  

AbstractAnxiety can be an adaptive process that promotes harm avoidance. It is accompanied by shifts in cognitive processing, but the precise nature of these changes and the neural mechanisms that underlie them are not fully understood. One theory is that anxiety impairs concurrent (non-harm related) cognitive processing by commandeering finite neurocognitive resources. For example, we have previously shown that anxiety reliably ‘speeds up time’, promoting temporal underestimation, possibly due to loss of temporal information. Whether this is due anxiety ‘overloading’ neurocognitive processing of time is unknown. We therefore set out to understand the neural correlates of this effect, examining whether anxiety and time processing overlap, particularly in regions of the cingulate cortex. Across two studies (an exploratory Study 1, N=13, followed by a pre-registered Study 2, N=29) we combined a well-established anxiety manipulation (threat of shock) with a temporal bisection task while participants were scanned using functional magnetic resonance imaging. Consistent with our previous work, time was perceived to pass more quickly under induced anxiety. Anxiety induction led to widespread activation in cingulate cortex, while the perception of longer intervals was associated with more circumscribed activation in a mid-cingulate area. Importantly, conjunction analysis identified convergence between anxiety and time processing in the insula and mid-cingulate cortex. These results provide tentative support for the hypothesis that anxiety impacts cognitive processing by overloading already-in-use neural resources. In particular, overloading mid-cingulate cortex capacity may drive emotion-related changes in temporal perception, consistent with the hypothesised role of this region in mediating cognitive affective and behavioural responses to anxiety.


Author(s):  
Céline Cunen ◽  
Nils Lid Hjort ◽  
Tore Schweder

The recent article ‘Satellite conjunction analysis and the false confidence theorem’ (Balch et al . 2019, Satellite conjunction analysis and the false confidence theorem. Proc. R. Soc. A 475 , 20180565) points to certain difficulties with Bayesian analysis when used for models for satellite conjuntion and ensuing operative decisions. Here, we supplement these previous analyses and findings with further insights, uncovering what we perceive of as being the crucial points, explained in a prototype set-up where exact analysis is attainable. We also show that a different and frequentist method, involving confidence distributions, is free of the false confidence syndrome.


2019 ◽  
Vol 30 (5) ◽  
pp. 2766-2776 ◽  
Author(s):  
John P Powers ◽  
John L Graner ◽  
Kevin S LaBar

Abstract Distancing is an effective tactic for emotion regulation, which can take several forms depending on the type(s) of psychological distance being manipulated to modify affect. We recently proposed a neurocognitive model of emotional distancing, but it is unknown how its specific forms are instantiated in the brain. Here, we presented healthy young adults (N = 34) with aversive pictures during functional magnetic resonance imaging to directly compare behavioral performance and brain activity across spatial, temporal, and objective forms of distancing. We found emotion regulation performance to be largely comparable across these forms. A conjunction analysis of activity associated with these forms yielded a high degree of overlap, encompassing regions of the default mode and frontoparietal networks as predicted by our model. A multivariate pattern classification further revealed distributed patches of posterior cortical activation that discriminated each form from one another. These findings not only confirm aspects of our overarching model but also elucidate a novel role for cortical regions in and around the parietal lobe in selectively supporting spatial, temporal, and social cognitive processes to distance oneself from an emotional encounter. These regions may provide new targets for brain-based interventions for emotion dysregulation.


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