Training the attentional blink:subclinical depression decreases learning potential

The attentional blink (AB) reflects a temporal restriction of selective attention and is generally regarded as a very robust phenomenon. However, previous studies have found large individual differences in AB performance, and under some training conditions the AB can be reduced significantly. One factor that may account for individual differences in AB magnitude is the ability to accurately time attention. In the current study, we focus on the sensitivity for temporal information on the ability to control attention. Following a visual AB task, a time estimation task was presented in either the visual or auditory modality, followed by another visual AB task. It was found that the time estimation training in both the auditory and visual modality reduced AB magnitude. Although a reduction in AB magnitude was also observed when individuals were trained on a control task (either an auditory frequency or visual line length estimation task), the effect was significantly larger following the time estimation tasks. In addition, it was found that individuals who showed most improvement on the visual time estimation task, also showed the largest reduction in AB magnitude, which was not the case for individuals who were trained on the control tasks. Finally, a negative correlation was observed between depression scores (tested by Beck Depression Inventory-Short Form (BDI-SF) scores and the improvement in the AB and time estimation tasks. Our findings demonstrate clear links between timing ability and mechanisms to control attention and emotion

Intrinsic prefrontal organization underlies associations between achievement motivation and delay discounting

Achievement motivation is a core component of human decision making. However, neural mechanisms that link achievement motivation and intertemporal choice have not yet been elucidated. Here, we examined neural pathways underlying the relationship between achievement motivation and intertemporal choice using a delay discounting task and resting-state functional magnetic resonance imaging on 86 healthy subjects. Behaviorally, delay discounting rate was positively correlated with achievement motivation. Functional coupling of the dorsolateral prefrontal cortex (dlPFC) with the medial prefrontal cortex (mPFC), medial orbitofrontal cortex and ventral striatum was positively correlated with achievement motivation. Notably, the mediation analysis showed that the impact of achievement motivation on delay discounting was mediated by intrinsic connectivity between the dlPFC and mPFC. Our findings suggest that intrinsic organization within the prefrontal cortex plays a key role in linking achievement motivation and intertemporal choice

Role of the amygdala in disrupted integration and effective connectivity of cortico-subcortical networks in apathy

Background Apathy is a quantitative reduction in motivation and goal-directed behaviors, not only observed in neuropsychiatric disorders, but also present in healthy populations. Although brain abnormalities associated with apathy in clinical disorders have been studied, the organization of brain networks in healthy individuals has yet to be identified. Method We examined properties of intrinsic brain networks in healthy individuals with varied levels of apathy. By using functional magnetic resonance imaging in combination with graph theory analysis and dynamic causal modeling analysis, we tested communications among nodes and modules as well as effective connectivity among brain networks. Results We found that the average participation coefficient of the subcortical network, especially the amygdala, was lower in individuals with high than low apathy. Importantly, we observed weaker effective connectivity fromthe hippocampus and parahippocampal gyrus to the amygdala, and from the amygdala to the parahippocampal gyrus and medial frontal cortex in individuals with apathy. Conclusion These findings suggest that individuals with high apathy exhibit aberrant communication within the cortical-to-subcortical network, characterized by differences in amygdala-related effective connectivity. Our work sheds light on the neural basis of apathy in subclinical populations and may have implications for understanding the development of clinical conditions that feature apathy.</p

Dissociated deficits of anticipated and experienced regret in at-risk suicidal individuals

Backgrounds: Decision-making deficits have been reported as trans-diagnostic characteristics of vulnerability to suicidal behaviors, independent of co-existing psychiatric disorders. Individuals with suicidal behaviors often regret their decision to attempt suicide and may have impairments in future-oriented processing. However, it is not clear how people with suicidal dispositions use future-oriented cognition and past experience of regret to guide decision-making. Here, we examined the processes of regret anticipation and experience in subclinical youth with and without suicidal ideation during value-based decision-making. Methods: In total, 80 young adults with suicidal ideation and 79 healthy controls completed a computational counterfactual thinking task and self-reported measures of suicidal behaviors, depression, anxiety, impulsivity, rumination, hopelessness, and childhood maltreatment. Results: Individuals with suicidal ideation showed a reduced ability to anticipate regret compared to healthy controls. Specifically, suicidal ideators’ experience of regret/relief was significantly different from that of healthy controls upon obtained outcomes, while their disappointment/pleasure experience was not significantly different from healthy controls. Conclusion: These findings suggest that young adults with suicidal ideation have difficulty predicting the consequences or the future value of their behavior. Individuals with suicidal ideation showed impairments in value comparison and flat affect to retrospective rewards, whereas individuals with high suicidality showed blunted affect to immediate rewards. Identifying the counterfactual decision-making characteristics of at-risk suicidal individuals may help to elucidate measurable markers of suicidal vulnerability and identify future intervention targets.</p

Neurocomputational mechanisms underlying fear-biased adaptation learning in changing environments

AU Humans: Please confirm that all heading levels are represented correctly are able to adapt to the fast-changing world by estimating : statistical regularities of the environment. Although fear can profoundly impact adaptive behaviors, the computational and neural mechanisms underlying this phenomenon remain elusive. Here, we conducted a behavioral experiment (n = 21) and a functional magnetic resonance imaging experiment (n = 37) with a novel cue-biased adaptation learning task, during which we simultaneously manipulated emotional valence (fearful/neutral expressions of the cue) and environmental volatility (frequent/infrequent reversals of reward probabilities). Across 2 experiments, computational modeling consistently revealed a higher learning rate for the environment with frequent versus infrequent reversals following neutral cues. In contrast, this flexible adjustment was absent in the environment with fearful cues, suggesting a suppressive role of fear in adaptation to environmental volatility. This suppressive effect was underpinned by activity of the ventral striatum, hippocampus, and dorsal anterior cingulate cortex (dACC) as well as increased functional connectivity between the dACC and temporal-parietal junction (TPJ) for fear with environmental volatility. Dynamic causal modeling identified that the driving effect was located in the TPJ and was associated with dACC activation, suggesting that the suppression of fear on adaptive behaviors occurs at the early stage of bottom-up processing. These findings provide a neuro-computational account of how fear interferes with adaptation to volatility during dynamic environments.</p

Dissociation of neural substrates of response inhibition to negative information between implicit and explicit facial go/nogo tasks: evidence from an electrophysiological study

Creative Commons Attribution LicenseBackground: Although ample evidence suggests that emotion and response inhibition are interrelated at the behavioral and neural levels, neural substrates of response inhibition to negative facial information remain unclear. Thus we used event-related potential (ERP) methods to explore the effects of explicit and implicit facial expression processing in response inhibition. Methods: We used implicit (gender categorization) and explicit emotional Go/Nogo tasks (emotion categorization) in which neutral and sad faces were presented. Electrophysiological markers at the scalp and the voxel level were analyzed during the two tasks. Results: We detected a task, emotion and trial type interaction effect in the Nogo-P3 stage. Larger Nogo-P3 amplitudes during sad conditions versus neutral conditions were detected with explicit tasks. However, the amplitude differences between the two conditions were not significant for implicit tasks. Source analyses on P3 component revealed that right inferior frontal junction (rIFJ) was involved during this stage. The current source density (CSD) of rIFJ was higher with sad conditions compared to neutral conditions for explicit tasks, rather than for implicit tasks. Conclusions: The findings indicated that response inhibition was modulated by sad facial information at the action inhibition stage when facial expressions were processed explicitly rather than implicitly. The rIFJ may be a key brain region in emotion regulation.This research was supported by the National Natural Science Foundation of China (31000503, 91232717, 31100812, 81301176, and 81300944) and the Ministry of Science and Technology (2011CB707805)

Apatinib combined with camrelizumab in the treatment of recurrent/metastatic nasopharyngeal carcinoma: a prospective multicenter phase II study

BackgroundPreclinical studies demonstrated that immune checkpoint inhibitors combined with antiangiogenic drugs have a synergistic anti-tumor effect. This present phase II trial aimed to evaluate the efficacy and safety of apatinib combined with camrelizumab in patients with recurrent/metastatic nasopharyngeal carcinoma (RM-NPC).MethodsPatients with RM-NPC were administered with apatinib at 250 mg orally once every day and with camrelizumab at 200 mg via intravenous infusion every 2 weeks until the disease progressed or toxicity became unacceptable. The objective response rate (ORR) was the primary endpoint, assessed using RECIST version 1.1. Progression-free survival (PFS), overall survival (OS), disease control rate (DCR) and safety were the key secondary endpoints. This study was registered with ClinicalTrials.gov, NCT04350190.ResultsThis study enrolled 26 patients with RM-NPC between January 14, 2021 and September 15, 2021. At data cutoff (March 31, 2023), the median duration of follow-up was 16 months (ranging from 1 to 26 months). The ORR was 38.5% (10/26), the disease control rate (DCR) was 61.5% (16/26), and the median PFS was 6 months (IQR 3.0-20.0). The median OS was 14 months (IQR 6.0-21.25). Treatment-related grade 3 or 4 adverse events occurred in seven (26.9%) patients, and comprised anemia (7.7%), stomatitis (3.8%), headache (3.8%), pneumonia (7.7%), and myocarditis (3.8%). There were no serious treatment-related adverse events or treatment-related deaths.ConclusionIn patients with RM-NPC, apatinib plus camrelizumab showed promising antitumor activity and manageable toxicities

Dissociable Modulation of Overt Visual Attention in Valence and Arousal Revealed by Topology of Scan Path

Emotional stimuli have evolutionary significance for the survival of organisms; therefore, they are attention-grabbing and are processed preferentially. The neural underpinnings of two principle emotional dimensions in affective space, valence (degree of pleasantness) and arousal (intensity of evoked emotion), have been shown to be dissociable in the olfactory, gustatory and memory systems. However, the separable roles of valence and arousal in scene perception are poorly understood. In this study, we asked how these two emotional dimensions modulate overt visual attention. Twenty-two healthy volunteers freely viewed images from the International Affective Picture System (IAPS) that were graded for affective levels of valence and arousal (high, medium, and low). Subjects' heads were immobilized and eye movements were recorded by camera to track overt shifts of visual attention. Algebraic graph-based approaches were introduced to model scan paths as weighted undirected path graphs, generating global topology metrics that characterize the algebraic connectivity of scan paths. Our data suggest that human subjects show different scanning patterns to stimuli with different affective ratings. Valence salient stimuli (with neutral arousal) elicited faster and larger shifts of attention, while arousal salient stimuli (with neutral valence) elicited local scanning, dense attention allocation and deep processing. Furthermore, our model revealed that the modulatory effect of valence was linearly related to the valence level, whereas the relation between the modulatory effect and the level of arousal was nonlinear. Hence, visual attention seems to be modulated by mechanisms that are separate for valence and arousal

An ERP study on shift of spatial attention resulting from number processing

Using the &quot;stimulus-delay-target&quot; experimental model, the brain mechanism of visual-spatial attention shift after number processing was conducted on 13 participants by using event-related potentials (ERP) technology. Results show that influence of the number processing on the spatial attention is indexed by the P3 component; parietal lobes at both sides may be the main neural substrate for number processing and spatial attention, and the numerical-spatial interaction mainly occurs in the response selection stage.;Using the &quot;stimulus-delay-target&quot; experimental model, the brain mechanism of visual-spatial attention shift after number processing was conducted on 13 participants by using event-related potentials (ERP) technology. Results show that influence of the number processing on the spatial attention is indexed by the P3 component; parietal lobes at both sides may be the main neural substrate for number processing and spatial attention, and the numerical-spatial interaction mainly occurs in the response selection stage.</p

Orienting in voluntary and involuntary attention conditions

To investigate the orienting of visuospatial attention, the attention type (voluntary vs. involuntary) was manipulated in a within-subject design, and event-related potentials (ERPs) were recorded in a peripheral cued, line-orientation discrimination task. A larger and later contralateral P1 and a smaller and later contralateral N1 were elicited by the valid trails relative to the invalid trails in the involuntary attention condition, whereas larger P1 and N1 were elicited by the valid trails in the voluntary attention condition. The present results provide evidence for the dissociation between voluntary and involuntary attention in one task.To investigate the orienting of visuospatial attention, the attention type (voluntary vs. involuntary) was manipulated in a within-subject design, and event-related potentials (ERPs) were recorded in a peripheral cued, line-orientation discrimination task. A larger and later contralateral P1 and a smaller and later contralateral N1 were elicited by the valid trails relative to the invalid trails in the involuntary attention condition, whereas larger P1 and N1 were elicited by the valid trails in the voluntary attention condition. The present results provide evidence for the dissociation between voluntary and involuntary attention in one task