Cerebral cortex最新文献

Metacontrol refers to the ability to dynamically adjust cognitive-control strategies, ensuring a balance between persistence and flexibility. Empirical findings point to a strong link between metacontrol and emotion, but the mechanistic underpinnings of this link remain unknown. Here, we had two goals. First, we hypothesized that metacontrol and emotion are mechanistically linked through aperiodic EEG activity, in the sense that both positive emotion and metacontrol flexibility come with increases, and both negative emotion and metacontrol persistence with decreases of aperiodic activity. Second, we tested whether and to what degree emotional stimuli affect behavior and aperiodic activity automatically. In a large sample (n = 120), we examined EEG and behavioral data from three tasks in which we systematically varied the task-relevance of the emotional information presented to participants. As hypothesized, positive pictures resulted in higher aperiodic activity than negative pictures. Task context and, more specifically, the relevance of emotional stimuli significantly influenced overt behavior but had no effect on aperiodic activity. We conclude that positive and negative emotions may represent the phenomenal "feel" of metacontrol biases towards flexibility and persistence, respectively, and that the degree to which processes are affected by emotional content automatically depends on the process under consideration.

Little is known about neural mechanisms that suppress learning, although such mechanisms are crucial for adaptive learning, which occurs selectively for items relevant to an observer's task but not for task-irrelevant items. Here, we examined neural mechanisms involved in suppressing visual perceptual learning (VPL), a type of visual skill learning, for a repeatedly exposed task-irrelevant coherent motion direction. The direction was either perceptually salient (suprathreshold for coherent motion detection) or weak (near detection threshold). Excitatory and inhibitory processing of the task-irrelevant direction during exposure was measured in early visual areas (V1 and V2) in the occipital lobes with functional magnetic resonance spectroscopy (fMRS). The results showed that, compared to near threshold exposure, VPL for the coherent motion direction was suppressed in suprathreshold exposure. Excitatory processing in early visual areas, as reflected in the concentration of glutamate, was reduced during suprathreshold compared to near threshold exposure. No modulation of inhibitory processing, as reflected in the concentration of γ-aminobutyric acid (GABA), was found. These results suggest that a gating mechanism operates within early visual areas that acts to suppress VPL for salient task-irrelevant signals by reducing excitatory processing.

Socially avoidant individuals, who are vulnerable to interpersonal conflict and social rejection, are characterized as low social approach motivation and high social avoidance motivation. However, the neural underpinnings of the influence of social rejection on socially avoidant individuals have not been fully studied. This study utilized EEG-based hyperscanning to examine the interbrain synchrony (IBS) of 18 socially avoidant dyads and 18 comparison dyads during a cooperative task. To examine the effects of social rejection on interpersonal interaction, satisfaction of belonging need and IBS during the cooperative task were compared between socially avoidant group and non-avoidant group before and after social rejection. Results showed that (i) satisfaction of belonging need of social avoidant group decreased significantly after rejection, with no significant difference between groups before rejection; (ii) alpha and theta IBS was higher in the socially avoidant group than in the non-avoidant group after social rejection, while no significant difference was observed between groups before rejection; (iii) in frontal and parietal-occipital regions, the causal directionality from the non-avoidant individual to socially avoidant individual was significantly increased after rejection. These findings advance the understanding of the paradox of social avoidance and the yearning for belonging in a neuroscience perspective.

Steady-state evoked potentials research has provided significant insights into temporal dynamics of attentional processes. While these studies focused primarily on group-level inspection, there is a need for further research employing methodological approaches that enable the examination of individual-level variability, often linked to various cognitive and clinical outcomes. In the present study (n = 29), we aimed to measure and discern attentional shift processes, examining both group and individual subject dynamics. We utilized electroencephalographic frequency tagging to examine attentional engagement, disengagement, and reengagement while participants switched focus between four flickering stimuli. Analysis of ssVEPs revealed significant changes in amplitude between attentional conditions. Group-level results indicated an increase in activity during engagement with the first target, followed by a decrease upon disengagement, while reengagement with the second target showed a corresponding increase in activity occurring on average 110 ms prior to disengagement. Distinct individual patterns emerged, with participants showing either disengagement, reengagement, both, or no shifts. Notably, the timing and order of these attentional shifts varied considerably. These findings demonstrate the ability of this approach to quantify attentional shifts on both group and individual-level, providing a foundation for further research into individual differences in attentional control, with implications for understanding adaptive and maladaptive psychological functioning.

Interpersonal action monitoring, i.e., the ability to monitor other people's actions, is essential during face-to-face interactions. Previous evidence from two independent research lines suggests that both how we represent the interaction goal and the human/non-human nature of the co-actor may affect how we process (and react to) their mistakes. Here, we examined in a full-factorial design whether these two factors modulate how we monitor someone else's errors during minimally joint tasks. During functional magnetic resonance imaging (fMRI), participants interacted with a human or the computer while sharing or not the goal of playing a melody together (shared vs. individual goal conditions). We used implied-motion pictures of a human hand to represent the human partner's responses, while a robotic piston represented the computer's ones. Despite the minimal nature of the interaction, multivariate pattern analysis revealed that it was possible to decode the human/non-human nature of the partner from post-error brain activation patterns but only in the shared goal condition. With both partners, post-error behavioral adaptations in this condition were associated with activation of the pre-supplementary motor area and right anterior insula, brain regions responsible for proactive action control. Goal sharing is thus a powerful factor in boosting interpersonal action monitoring with both human and non-human partners.

Congenital heart disease is linked to substantial variability in neurodevelopmental outcomes, with sex being a key contributing factor. Compared with females, male congenital heart disease infants often show greater impairments in motor, cognitive, and language development. However, studies on sex differences in early brain development among congenital heart disease patients remain limited. To fill these gaps, this study included 79 infants with complex congenital heart disease (42 males, 37 females) and 87 healthy controls (47 males, 40 females), collecting magnetic resonance imaging data, clinical information, and neurodevelopmental assessments. We examined sex-specific effects on global and regional brain development in congenital heart disease infants aged 1 to 2 yr using imaging and statistical analysis. Male congenital heart disease infants showed global brain volume reduction and regional cortical delays, including increased cortical thickness and gray matter volume. In contrast, female congenital heart disease infants had no significant global volume change but exhibited localized structural abnormalities, such as reduced surface area and increased cortical thickness. Notably, reduced global brain volume in congenital heart disease males was associated with poorer gross motor skills. Distinct sex differences in brain development exist among congenital heart disease infants during early life. Recognizing these differences is critical for developing sex-specific treatment and neuroprotective strategies.

Choice consistency denotes the capacity to maintain stable, coherent preferences across diverse contexts-a cornerstone of rational decision-making. However, real-world decisions frequently diverge from normative models, marked by inconsistencies and irrationalities. Memory processes may underlie this variability, influencing the formation and maintenance of choice consistency. Yet, the interplay between memory and choice consistency, particularly their shared neural substrates, remains poorly understood. To address these gaps, we developed a novel behavioral paradigm integrating memory retrieval and food-based decision tasks. Resting-state and task functional magnetic resonance imaging data were acquired from 44 healthy young adults (age range: 18 to 27 years). Behaviorally, remembered food items exhibited significantly faster choice reaction times compared to forgotten items. Leveraging data-driven connectome-based predictive modeling of resting-state functional connectivity, we identified distinct neural predictors: intra-default mode network connectivity and default mode network-memory network connectivity positively predicted memory accuracy, whereas default mode network-frontoparietal control network connectivity negatively predicted memory accuracy. Furthermore, intra-default mode network connectivity and default mode network-frontoparietal control network connectivity positively predicted choice consistency. These findings advance our understanding of memory-decision interactions, highlighting the default mode network and frontoparietal control network as critical neural substrates that bridge mnemonically modulated value signals and choice consistency.

Eye blinks modulate neural activity in visual areas even if the visual input is unchanged. Is the influence of blinking defined by the motor output of the blink? We analyzed blink-related neural activity with laminar resolution in V1 of two macaque monkeys in two conditions, viewing a video and at rest. During free viewing a video, blinks induced a modulation of the local field potential (LFP) in the theta, beta, and gamma band with a granular/infragranular focus. The multiunit activity (MUA) decreased around blink execution. Surprisingly, when comparing the results to blinks executed during the rest condition, we found that MUA increased around blinks. The blink-related LFP power changes, while increasing after a blink in both conditions, were significantly different in amplitude and latency. Our findings show that the blink induced modulation of V1 activity is not determined by the motor execution but depends on the condition in which the movement is executed. This suggests that interactions between movement and neural processes in sensory areas are context-dependent. These interactions may play an important role in predictive coding within the framework of active sensing.

Adequately responding towards a threat is a crucial mechanism for survival. Adapting this response when a threat-associated stimulus or situation has become safe requires extinction learning and formation of an extinction memory. Functional magnetic resonance imaging (fMRI) affords to longitudinally monitor network activity, yet, in the rodent, still suffers from significant variability of results and practical restrictions, mainly related to the different approaches of subject immobilization. Physical restraint of awake animals permits only short scanning times, while anesthesia can induce uncontrolled brain states with limited stimulus responsiveness and processing. Here, we implement a paradigm where light medetomidine sedation permits long scanning times in a stable brain state with functional characteristics comparable to the human resting state. We observe responsiveness of the brain to visual stimulation and large-scale resting-state network activity with small-world connectivity features. After visual fear conditioning outside the MRI scanner, rats exposed to the unreinforced visual conditioned stimulus in this stable persistent activity state inside the scanner (extinction) exhibit a significantly lower conditioned fear response when re-exposed to the conditioned stimulus days after scanning (test). We present a brain state-informed paradigm easily adaptable for future studies involving invasive neural manipulations to causally investigate extinction and its memory consolidation.

Face recognition depends upon the ability to match a visual image to a representation stored in memory. During natural viewing, observers fixate centrally on faces, resulting in face parts appearing in specific spatial locations. We examined whether this perceptual experience influences the cognitive and neural mechanisms involved in face recognition. Participants viewed left/right or upper/lower face halves presented in typical (eg left face half in left visual field) or atypical (eg left face half in right visual field) locations. For familiar faces, familiarity judgments were faster and more accurate when face halves were displayed in typical locations. To examine the neural correlates of this recognition bias, fMRI was used to measure responses to familiar face halves presented in typical or atypical spatial locations. Early visual areas (V1-V4) showed responses primarily determined by visual field and were not sensitive to typical spatial presentation. In contrast, the occipital face area and the fusiform face area exhibited greater activations for face halves presented in their typical spatial location. This bias was also evident in regions beyond the visual brain. These findings suggest that higher-level representations used in the perceptual processing of familiar faces are influenced by statistical regularities in real-world face viewing.