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Errors typically trigger post-error adjustments aimed at improving subsequent reactions within a single task, but little work has focused on whether these adjustments are task-general or task-specific across different tasks. We collected behavioral and electrophysiological (EEG) data when participants performed a psychological refractory period paradigm. This paradigm required them to complete Task 1 and Task 2 separated by a variable stimulus onset asynchrony (SOA). Behaviorally, post-error slowing and post-error accuracy exhibited task-general features at short SOAs but some task-specific features at long SOAs. EEG results manifest that task-general adjustments had a short-lived effect, whereas task-specific adjustments were long-lasting. Moreover, error awareness specifically conduced to the improvement of subsequent sensory processing and behavior performance in Task 1 (the task where errors occurred). These findings demonstrate that post-error adjustments rely on both transient, task-general interference and longer-lasting, task-specific control mechanisms simultaneously, with error awareness playing a crucial role in determining these mechanisms. We further discuss the contribution of central resources to the task specificity of post-error adjustments.
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Electroencefalografía , Desempeño Psicomotor , Humanos , Masculino , Femenino , Adulto Joven , Desempeño Psicomotor/fisiología , Adulto , Encéfalo/fisiología , Tiempo de Reacción/fisiología , Periodo Refractario Psicológico/fisiologíaRESUMEN
Human control is characterized by its flexibility and adaptability in response to the conditional probability in the environment. Previous studies have revealed that efficient conflict control could be attained by predicting and adapting to the changing control demand. However, it is unclear whether cognitive flexibility could also be gained by predicting and adapting to the changing control demand. The present study aimed to explore this issue by combining the model-based analyses of behavioral and neuroimaging data with a probabilistic cued task switching paradigm. We demonstrated that the Bayesian surprise (i.e. unsigned precision-weighted prediction error [PE]) negatively modulated the connections among stimulus processing brain regions and control regions/networks. The effect of Bayesian surprise modulation on these connections guided control engagement as reflected by the control PE effect on behavior, which in turn facilitated cognitive flexibility. These results bridge a gap in the literature by illustrating the neural and behavioral effect of control demand prediction (or PE) on cognitive flexibility and offer novel insights into the source of switch cost and the mechanism of cognitive flexibility.
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Encéfalo , Señales (Psicología) , Humanos , Teorema de Bayes , Encéfalo/fisiología , Mapeo Encefálico , Cognición/fisiología , Imagen por Resonancia MagnéticaRESUMEN
Attentional blink pertains to the performance of participants with a severe decline in identifying the second target presented after the first target reported correctly within 200-500 ms in a rapid serial visual presentation. The current study was conducted to investigate the neural mechanism of the effect of the distractor (D1) that immediately follows first target to attentional blink by altering whether D1 was substituted with a blank with electroencephalography recording. The results showed that D1 interfered with the attentional enhancement and working memory encoding in both single-target rapid serial visual presentation task and dual-target rapid serial visual presentation task, which were mainly manifested in delayed and attenuated P3a and diminished P3b of first target. Single-trial analysis indicated that first target and second target will compete with each other for working memory encoding resources in short lag, but not in the long lag. In addition, D1 interfered with the working memory encoding of second target under short lag rather than long lag in the dual-target rapid serial visual presentation task. These results suggested that attentional blink can be attributed to the limited working memory encoding resource, whereas the amount of available resources is subject to modulation by attention. The D1 hinders the attention enhancement of first target, thereby exacerbating attentional blink.
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Parpadeo Atencional , Humanos , Estimulación Luminosa/métodos , Electroencefalografía/métodos , Atención , Análisis MultivarianteRESUMEN
Empirical evidence on error processing comes from the comparison between errors and correct responses in general, but essential differences may exist between different error types. Typically, cognitive control tasks elicit errors without conflicts (congruent errors) and with conflicts (incongruent errors), which may employ different monitoring and adjustment mechanisms. However, the neural indicators that distinguish between both error types remain unclear. To solve this issue, behavioral and electrophysiological data were measured while subjects performed the flanker task. Results showed that a significant post-error improvement in accuracy on incongruent errors, but not on congruent errors. Theta and beta power were comparable between both error types. Importantly, the basic error-related alpha suppression (ERAS) effect was observed on both errors, whereas ERAS evoked by incongruent errors was greater than congruent errors, indicating that post-error attentional adjustments are both source-general and source-specific. And the brain activity in alpha band, but not theta or beta band, successfully decoded congruent and incongruent errors. Furthermore, improved post-incongruent error accuracy was predicted by a measure of post-error attentional adjustments, the alpha power. Together, these findings demonstrate that ERAS is a reliable neural indicator for identifying error types, and directly conduces to the improvement of post-error behavior.
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Atención , Electroencefalografía , Humanos , Electroencefalografía/métodos , Atención/fisiología , Tiempo de Reacción/fisiologíaRESUMEN
Self-referential information has been shown to optimize behavioral performance in various domains. The present study examined the role of self-referential information as a cue to enhance cognitive control and, more specifically, conflict adaptation. A revised color Stroop task was used with stimuli consisting of possessive pronouns and color words (e.g., "my green"). The results showed that self-referential information reduced conflict adaptation (the congruency sequence effect at trial level in Experiment 1, at block level in Experiment 2, and the list-wide proportion congruency effect at block level in Experiment 3). These findings suggest that self-referential information can act as a cue to optimize conflict adaptation. This study highlights the role of self-referential information in cognitive control adjustments.
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Conflicto Psicológico , Humanos , Tiempo de Reacción , Test de StroopRESUMEN
Self-representations guide and shape our thoughts and behaviour. People usually exhibit inherent biases in perception, attention, and memory to favour the information associated with themselves over that associated with others. The present study explored the phenomenon of self-bias in working memory (WM), specifically how self-referential processing impacts WM precision. Four precision-based experiments were conducted to assess the recall precision of self-referential items and items associated with other social agents. The findings revealed a robust self-prioritisation effect in WM precision, wherein self-referential items were recalled with greater precision than items associated with other social agents. Additionally, increased precision for self-referential items did not decrease the precision for simultaneously remembered items. This effect was limited by the total amount of WM resources and not influenced by a perceptual distractor. The inherent self-bias in WM can serve as a proxy to access the role self-representation in goal-oriented cognitive processing, providing a means of exploring the interaction between self-reference and high-level cognitive function.
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Memoria a Corto Plazo , Autoimagen , Humanos , Masculino , Femenino , Adulto Joven , Recuerdo Mental , Atención/fisiología , Adulto , Asignación de RecursosRESUMEN
Errors can elicit post-error adjustments that serve to optimize performance by preventing further errors. An essential but unsolved issue is that whether post-error adjustments are domain-general or domain-specific, which was investigated in the present study through eliciting different types of errors. Behavioral and electrophysiological data were recorded when male and female subjects performed the Eriksen flanker task. For this study, we examined the aforementioned issue by combining event-related potential and multivariate pattern analysis. The results indicated that post-error slowing, error-related negativity, and error positivity were comparable between congruent and incongruent errors, indicating that errors triggered domain-general interference mechanisms. Whereas post-error accuracy and late positive potential elicited by incongruent errors were larger than those elicited by congruent errors, exhibiting domain-specific control adjustment mechanisms. Importantly, no successful decoding soon after errors was found between congruent and incongruent errors, but above-chance decoding was observed between these two types of errors with increasing time, which further support that domain-general adjustments occurred in the early stage, whereas domain-specific adjustments appeared in the late stage. Furthermore, brain-behavior correlation results suggested that the late post-error adjustments predicted subsequent behavior performance. Taken together, this study revealed that early domain-general interference adjustments induced by errors are reflected in error detection and error awareness, which are independent of error types; on the contrary, late domain-specific control adjustments are reflected in attentional adjustments, which are modulated by error types.SIGNIFICANCE STATEMENTTo date, clear evidence on the specificity of post-error adjustments is lacking. The present study provides neurophysiological evidence that post-error adjustments simultaneously rely on both domain-general and domain-specific mechanisms. Event-related potential results indicated that domain-general adjustments were accompanied by the interference of error detection and error awareness. In contrast, domain-specific adjustments were associated with attentional adjustments. Multivariate pattern analysis further decoded the two features of post-error adjustments in the early stage matching the time patterns of error-related negativity and error positivity and in the late stage corresponding to the late positive potential. Temporal generalization analysis showed that domain-specific processing appeared stably in late post-error adjustments. Hence, we propose that post-error different stages may determine the specificity of post-error adjustments.
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The brain functions as an accurate circuit that regulates information to be sequentially propagated and processed in a hierarchical manner. However, it is still unknown how the brain is hierarchically organized and how information is dynamically propagated during high-level cognition. In this study, we developed a new scheme for quantifying the information transmission velocity (ITV) by combining electroencephalogram (EEG) and diffusion tensor imaging (DTI), and then mapped the cortical ITV network (ITVN) to explore the information transmission mechanism of the human brain. The application in MRI-EEG data of P300 revealed bottom-up and top-down ITVN interactions subserving P300 generation, which was comprised of four hierarchical modules. Among these four modules, information exchange between visual- and attention-activated regions occurred at a high velocity, related cognitive processes could thus be efficiently accomplished due to the heavy myelination of these regions. Moreover, inter-individual variability in P300 was probed to be attributed to the difference in information transmission efficiency of the brain, which may provide new insight into the cognitive degenerations in clinical neurodegenerative disorders, such as Alzheimer's disease, from the transmission velocity perspective. Together, these findings confirm the capacity of ITV to effectively determine the efficiency of information propagation in the brain.
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Encéfalo , Imagen de Difusión Tensora , Humanos , Encéfalo/fisiología , Cognición/fisiología , Electroencefalografía/métodos , Mapeo Encefálico/métodosRESUMEN
Analogical reasoning is important for human. We have found that a short executive attention intervention improved analogical reasoning performance in healthy young adults. Nevertheless, previous electrophysiological evidence was limited for comprehensively characterizing the neural mechanisms underlying the improvement. And although we hypothesized that the intervention improved active inhibitory control and attention shift first and then relation integration, it is still unclear whether there are two sequential cognitive neural activities were indeed changed during analogical reasoning. In the present study, we combined hypothesis with multivariate pattern analysis (MVPA) to explore the effects of the intervention on electrophysiology. Results showed that in the resting state after the intervention, alpha and high gamma power and the functional connectivity between the anterior and middle in the alpha band could discriminate the experimental group from the active control group, respectively. These indicated that the intervention influenced the activity of multiple bands and the interaction of frontal and parietal regions. In the analogical reasoning, alpha, theta, and gamma activities could also fulfill such discrimination, and furthermore, they were sequential (alpha first, theta, and gamma later). These results directly supported our previous hypothesis. The present study deepens our understanding about how executive attention contributes to higher-order cognition.
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Cognición , Solución de Problemas , Adulto Joven , Humanos , Solución de Problemas/fisiología , Cognición/fisiología , AtenciónRESUMEN
Morin suggested that one of the reasons for the difficulty in standardizing graphic codes is that the production of spoken language reduces the need for graphic codes. Here we try to extend their claims from a psychological perspective, which allows us to conclude that the puzzle of ideography is perhaps related to human psychological traits and psychological evolution.
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Lenguaje , HumanosRESUMEN
Humans show a pervasive bias for processing self- over other-related information, including in working memory (WM), where people prioritize the maintenance of self- (over other-) associated cues. To elucidate the neural mechanisms underlying this self-bias, we paired a self- versus other-associated spatial WM task with fMRI and transcranial direct current stimulation (tDCS) of human participants of both sexes. Maintaining self- (over other-) associated cues resulted in enhanced activity in classic WM regions (frontoparietal cortex), and in superior multivoxel pattern decoding of the cue locations from visual cortex. Moreover, ventromedial PFC (VMPFC) displayed enhanced functional connectivity with WM regions during maintenance of self-associated cues, which predicted individuals' behavioral self-prioritization effects. In a follow-up tDCS experiment, we targeted VMPFC with excitatory (anodal), inhibitory (cathodal), or sham tDCS. Cathodal tDCS eliminated the self-prioritization effect. These findings provide strong converging evidence for a causal role of VMPFC in driving self-prioritization effects in WM and provide a unique window into the interaction between social, self-referential processing and high-level cognitive control processes.SIGNIFICANCE STATEMENT People have a strong tendency to attend to self-related stimuli, such as their names. This self-bias extends to the automatic prioritization of arbitrarily self-associated stimuli held in working memory. Since working memory is central to high-level cognition, this bias could influence how we make decisions. It is therefore important to understand the underlying brain mechanisms. Here, we used neuroimaging and noninvasive neurostimulation techniques to show that the source of self-bias in working memory is the ventromedial PFC, which modulates activity in frontoparietal brain regions to produce prioritized representations of self-associated stimuli in sensory cortex. This work thus reveals a brain circuit underlying the socially motivated (self-referential) biasing of high-level cognitive processing.
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Sesgo Atencional/fisiología , Memoria a Corto Plazo/fisiología , Corteza Prefrontal/fisiología , Señales (Psicología) , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Estimulación Transcraneal de Corriente Directa , Adulto JovenRESUMEN
Feedback-related negativity (FRN) is believed to encode reward prediction error (RPE), a term describing whether the outcome is better or worse than expected. However, some studies suggest that it may reflect unsigned prediction error (UPE) instead. Some disagreement remains as to whether FRN is sensitive to the interaction of outcome valence and prediction error (PE) or merely responsive to the absolute size of PE. Moreover, few studies have compared FRN in appetitive and aversive domains to clarify the valence effect or examine PE's quantitative modulation. To investigate the impact of valence and parametrical PE on FRN, we varied the prediction and feedback magnitudes within a probabilistic learning task in valence (gain and loss domains, Experiment 1) and non-valence contexts (pure digits, Experiment 2). Experiment 3 was identical to Experiment 1 except that some blocks emphasized outcome valence, while others highlighted predictive accuracy. Experiments 1 and 2 revealed a UPE encoder; Experiment 3 found an RPE encoder when valence was emphasized and a UPE encoder when predictive accuracy was highlighted. In this investigation, we demonstrate that FRN is sensitive to outcome valence and expectancy violation, exhibiting a preferential response depending on the dimension that is emphasized.
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Encéfalo/fisiología , Aprendizaje Discriminativo/fisiología , Potenciales Evocados/fisiología , Retroalimentación Fisiológica/fisiología , Motivación/fisiología , Aprendizaje por Probabilidad , Adolescente , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Estimulación Luminosa/métodos , Análisis de Componente Principal/métodos , Distribución Aleatoria , Adulto JovenRESUMEN
The biological mediators that support cognitive-control and long-term weight-loss after laparoscopic sleeve gastrectomy (LSG) remain unclear. We measured peripheral appetitive hormones and brain functional-connectivity (FC) using magnetic-resonance-imaging with food cue-reactivity task in 25 obese participants at pre, 1 month, and 6 month after LSG, and compared with 30 normal weight controls. We also used diffusion-tensor-imaging to explore whether LSG increases brain structural-connectivity (SC) of regions involved in food cue-reactivity. LSG significantly decreased BMI, craving for high-calorie food cues, ghrelin, insulin, and leptin levels, and increased self-reported cognitive-control of eating behavior. LSG increased FC between the right dorsolateral prefrontal cortex (DLPFC) and the pregenual anterior cingulate cortex (pgACC) and increased SC between DLPFC and ACC at 1 month and 6 month after LSG. Reduction in BMI correlated negatively with increased FC of right DLPFC-pgACC at 1 month and with increased SC of DLPFC-ACC at 1 month and 6 month after LSG. Reduction in craving for high-calorie food cues correlated negatively with increased FC of DLPFC-pgACC at 6 month after LSG. Additionally, SC of DLPFC-ACC mediated the relationship between lower ghrelin levels and greater cognitive control. These findings provide evidence that LSG improved functional and structural connectivity in prefrontal regions, which contribute to enhanced cognitive-control and sustained weight-loss following surgery.
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Encéfalo/diagnóstico por imagen , Ansia/fisiología , Gastrectomía/tendencias , Red Nerviosa/diagnóstico por imagen , Obesidad/diagnóstico por imagen , Pérdida de Peso/fisiología , Adulto , Biomarcadores/sangre , Encéfalo/metabolismo , Femenino , Hormonas/sangre , Humanos , Laparoscopía/tendencias , Imagen por Resonancia Magnética/tendencias , Masculino , Red Nerviosa/metabolismo , Obesidad/sangre , Obesidad/cirugíaRESUMEN
Attentional disengagement is of great significance to individuals adapting to their environment who can benefit from disregarding the attraction of salient and task-irrelevant objects. Previous studies have suggested that, in addition to causing greater financial loss compared with neutral distractors, reward distractors hold attention longer than neutral distractors. However, few studies have directly compared the attentional disengagement differences between reward-associated and loss- or punishment-associated stimuli. In the current study, we used different color singleton stimuli tied to reward or punishment outcomes; the stimuli were present in the center of the screen. Participants were required to respond to a line within the target at a peripheral location. The results showed that the response to the target was slower when the central distractor was associated with a reward than with punishment. This finding reflects that, although participants understand that reward-associated and punishment-associated stimuli have an equal opportunity for the same economic benefit, they still take longer to disengage from a reward distractor compared with a punishment distractor.
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Atención , Recompensa , Atención/fisiología , Humanos , Tiempo de Reacción/fisiologíaRESUMEN
The ability to adjust our behavior flexibly depending on situational demands and changes in the environment is an important characteristic of cognitive control. Previous studies have proved that this type of adaptive control plays a crucial role in selective attention, but have barely explored whether and how attentional networks support adaptive control. In the present study, a Stroop task with a different proportion of incongruent trials was used to investigate the brain activity and connectivity of six typical attentional control networks (i.e., the fronto-parietal network (FPN), cingulo-opercular network (CON), default mode network (DMN), dorsal attention network (DAN), and ventral attention network/salience network (VAN/SN)) in the environment with changing control demand. The behavioral analysis indicated a decreased Stroop interference (incongruent vs. congruent trial response time [RT]) with the increase in the proportion of incongruent trials within a block, indicating that cognitive control was improved there. The fMRI data revealed that the attenuate Stroop interference was accompanied by the activation of frontal and parietal regions, such as bilateral dorsolateral prefrontal cortex and anterior cingulate cortex. Crucially, the improved cognitive control induced by the increased proportion of incongruent trials was associated with the enhanced functional connectivity within the five networks, and a greater connection between CON with the DAN/SN, and between DMN with the CON/DAN/SN. Meanwhile, however, the functional coupling between the FPN and VAN was decreased. These results suggest that flexible regulations of cognitive control are implemented by the large-scale reconfiguration of connectivity patterns among the attentional networks.
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Atención/fisiología , Corteza Cerebral/fisiología , Conectoma , Red en Modo Predeterminado/fisiología , Función Ejecutiva/fisiología , Red Nerviosa/fisiología , Desempeño Psicomotor/fisiología , Adolescente , Adulto , Corteza Cerebral/diagnóstico por imagen , Red en Modo Predeterminado/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Red Nerviosa/diagnóstico por imagen , Test de Stroop , Adulto JovenRESUMEN
Whether auditory processing of speech relies on reference to the articulatory motor information of speaker remains elusive. Here, we addressed this issue under a two-brain framework. Functional magnetic resonance imaging was applied to record the brain activities of speakers when telling real-life stories and later of listeners when listening to the audio recordings of these stories. Based on between-brain seed-to-voxel correlation analyses, we revealed that neural dynamics in listeners' auditory temporal cortex are temporally coupled with the dynamics in the speaker's larynx/phonation area. Moreover, the coupling response in listener's left auditory temporal cortex follows the hierarchical organization for speech processing, with response lags in A1+, STG/STS, and MTG increasing linearly. Further, listeners showing greater coupling responses understand the speech better. When comprehension fails, such interbrain auditory-articulation coupling vanishes substantially. These findings suggest that a listener's auditory system and a speaker's articulatory system are inherently aligned during naturalistic verbal interaction, and such alignment is associated with high-level information transfer from the speaker to the listener. Our study provides reliable evidence supporting that references to the articulatory motor information of speaker facilitate speech comprehension under a naturalistic scene.
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Percepción del Habla/fisiología , Habla/fisiología , Lóbulo Temporal/fisiología , Adulto , Anciano , Corteza Auditiva/fisiología , Mapeo Encefálico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Vías Nerviosas/fisiología , Adulto JovenRESUMEN
Obese individuals exhibit brain functional abnormalities in multiple regions implicated in reward/motivation, emotion/memory, homeostatic regulation, and executive control when exposed to food cues and during rest. However, it remains unclear whether abnormal brain responses to food cues might account for or relate to their abnormal activity in resting state. This information would be useful for understanding the neural mechanisms behind hyperactive responses to food cues, a critical marker of obesity. Resting-state functional magnetic resonance imaging (RS-fMRI) and a cue-reactivity fMRI task with high- (HiCal) and low-caloric (LoCal) food cues were employed to investigate brain baseline activity and food cue-induced activation differences in 44 obese participants (OB), in 37 overweight participants (OW), and in 37 normal weight (NW) controls. One-way analyses of variance showed there was a group difference in the left hippocampus/amygdala activity during resting state and during food-cue stimulation (pFWE < 0.05); post-hoc tests showed the OB group had both greater basal activity and greater food cue-induced activation than the OW and NW groups; OW had higher activity in the hippocampus/amygdala than the NW group, which was only significant during resting state. In the OB group, resting-state activity in the left hippocampus/amygdala was positively correlated with activation induced by HiCal food cues, and both of these measures correlated with body mass index (BMI). Mediation analysis showed that the relationship between BMI and hippocampus/amygdala response to HiCal food cues was mediated by their resting-state activity. These findings suggest a close association between obesity and brain functional abnormality in the hippocampus/amygdala. They also indicate that resting-state activity in the hippocampus/amygdala may impact these regions' responses to food cues.
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Amígdala del Cerebelo/fisiopatología , Señales (Psicología) , Alimentos , Hipocampo/fisiopatología , Obesidad/fisiopatología , Adulto , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Sobrepeso/fisiopatología , Descanso , Recompensa , Adulto JovenRESUMEN
Evidence indicates the significance of the fronto-parietal regions and inertia sensory processing from previous trials in cognitive flexibility. However, how flexible cognitive performance is achieved by causal interactions between cortical regions, particularly those between the fronto-parietal and stimulus processing regions, remains unknown. In the current study, the effective connectivity between the fronto-parietal and visual regions was examined in the context of a cued task-switching paradigm. We found that the fronto-parietal and visual cortex were differently activated during task transition (task repeat and task switch). Importantly, dynamic causal modeling (DCM) analysis revealed that task transition could modulate the effective connectivity between the fronto-parietal and visual cortex: task repeat decreased, while task switch enhanced, the coupling between the posterior parietal cortex (PPC) and the visual cortex. Furthermore, Granger causality analysis (GCA) showed that the dominant direction of influence was from the fronto-parietal regions to the visual cortex. Finally, individual differences in the top-down influence from the PPC to the visual cortex and the corresponding neural adjustment (task switchâtask repeat) was negatively associated with the behavioral switch cost. Our findings suggest that the interaction between the fronto-parietal and stimulus processing regions, particularly the top-down influence from the PPC to the visual cortex, is of particular importance in flexible cognitive performance.
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Cognición/fisiología , Lóbulo Frontal/fisiología , Lóbulo Parietal/fisiología , Desempeño Psicomotor/fisiología , Corteza Visual/fisiología , Adulto , Mapeo Encefálico , Femenino , Humanos , Masculino , Vías Nerviosas/fisiología , Tiempo de Reacción/fisiología , Percepción Visual/fisiología , Adulto JovenRESUMEN
BACKGROUND/OBJECTIVE: Laparoscopic sleeve gastrectomy (LSG) is an effective bariatric surgery to treat obesity, and involves removal of the gastric fundus where ghrelin is mainly produced. Ghrelin stimulates appetite and regulates food intake through its effect on the hypothalamus and hippocampus (HIPP). While ghrelin's role on the hypothalamus has been explored, little is known about its role on HIPP. We tested the hypothesis that LSG-induced reductions in ghrelin levels would be associated with changes in HIPP activity. SUBJECTS/METHODS: Brain activity was measured with amplitude of low-frequency fluctuations (ALFF) captured with resting-state functional magnetic resonance imaging (fMRI) in 30 obese participants, both before and after 1-month of LSG, and in 26 obese controls without surgery that were studied at baseline and 1-month later. A two-way analysis of variance (ANOVA) was performed to model the group and time effects on ALFF and resting-state functional connectivity. RESULTS: One-month post-LSG there were significant decreases in appetite, body mass index (BMI), fasting plasma ghrelin and leptin levels, anxiety, and ALFF in HIPP and ALFF increases in posterior cingulate cortex (PCC, PFWE < 0.05). Decreases in HIPP ALFF correlated positively with decreases in fasting ghrelin and anxiety, and increases in PCC ALFF correlated positively with decreases in anxiety. Seed-voxel correlation analysis showed stronger connectivity between HIPP and insula, and between PCC and dorsolateral prefrontal cortex (DLPFC) post-LSG. CONCLUSIONS: These findings suggest that ghrelin effects in HIPP modulate connectivity with the insula, which processes interoception and might be relevant to LSG-induced reductions in appetite/anxiety. Role of LSG in PCC and its enhanced connectivity with DLPFC in improving self-regulation following LSG requires further investigation.
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Cirugía Bariátrica , Ayuno/sangre , Ghrelina/sangre , Hipocampo/fisiopatología , Obesidad Mórbida/cirugía , Pérdida de Peso/fisiología , Adulto , Apetito/fisiología , Femenino , Encuestas Epidemiológicas , Hipocampo/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Obesidad Mórbida/diagnóstico por imagen , Obesidad Mórbida/fisiopatología , Resultado del TratamientoRESUMEN
People preferentially attend to external stimuli that are related to themselves compared with others. Whether a similar self-reference bias applies to internal representations, such as those maintained in working memory (WM), is presently unknown. We tested this possibility in four experiments, in which participants were first trained to associate social labels (self, friend, stranger) with arbitrary colors and then performed a delayed match-to-sample spatial WM task on color locations. Participants consistently responded fastest to WM probes at locations of self-associated colors (Experiments 1-4). This self-bias was driven not by differential exogenous attention during encoding or retrieval (Experiments 1 and 2) but by internal attentional prioritization of self-related representations during WM maintenance (Experiment 3). Moreover, self-prioritization in WM was nonstrategic, as this bias persisted even under conditions in which it hurt WM performance. These findings document an automatic prioritization of self-referential items in WM, which may form the basis of some egocentric biases in decision making.