European Journal of Neuroscience最新文献

The mismatch negativity (MMN) is a well-studied event-related potential (ERP) component in the EEG reflecting deviance detection in the auditory modality. It taps into the basic functioning of auditory regularity processing. The auditory multi-feature paradigm is widely used in sensitive and special populations to measure the MMN simultaneously for different sound features in a short amount of time. It is consensus in the field that both adaptation and genuine deviance detection contribute to the “classic” MMN computed as deviant minus standard ERP difference. However, no attempts have yet been made to disentangle adaptation from the “genuine” MMN in the multi-feature paradigm. Here, we propose a cascadic control condition for the auditory multi-feature paradigm that controls for adaptation and physical differences between standard and deviant sounds. Using this new paradigm, we measured the genuine MMN, computed as deviant minus control ERP difference, for frequency, location, intensity, and duration deviants. The genuine MMN amplitudes for frequency and location were found substantially smaller than in traditional paradigms. No genuine intensity MMN and only a later and smaller genuine duration MMN were found. The results suggest stronger contributions of adaptation than in the traditional oddball paradigm. Controlling for adaptation is particularly relevant in research concerning predictive processing and the use of the MMN as a biomarker related to impaired NMDA receptor synaptic transmission as observed in schizophrenia. The presented multi-feature cascadic control condition enables the measurement of the genuine MMN, which presumably reflects higher-order cortical computations, such as predictive processing, still in a short amount of time.

The Sunburst maze, first described 80 years ago by Tolman, Ritchie and Kalish (1946) and popularized by Tolman (1948), is widely regarded as a classic demonstration of cognitive map use in rats. In this task, animals trained on a circuitous path to a reward were presented with new paths, including a shortcut, after the original route was blocked. A substantial proportion of rats selected the shortcut, which Tolman et al. (1946; 1948) interpreted as evidence that animals have an internal spatial representation, or ‘cognitive map’. Despite the influence of this study, attempts to replicate it have been largely unsuccessful. This review critically examines a dozen replications involving rats, squirrel monkeys and humans, highlighting a range of alternative strategies, with only a fraction of experiments demonstrating shortcutting (17%). Instead, most studies found that animals either favoured paths adjacent to the original training route (32%), did not have a preference (26%), chose unremarkable paths (13%) or selected options consistent with previously rewarded responses (6%), suggesting a reliance on procedural or associative learning rather than demonstrating flexible spatial inference. Although the original experiment has been widely criticized for including a visual cue above the reward location, subsequent studies rarely found that this feature guided path choices (6%). Neurophysiological data from hippocampal lesion and head-direction cell studies further undermine the claim that shortcutting in the Sunburst maze depends on cognitive maps. We argue that this study, though historically significant, is a poor standalone demonstration of map-based navigation.

Binocular rivalry (BR) occurs when each eye is presented with mutually incompatible images, and the brain alternates between perceiving one image, the other or occasionally a mashup of both. Addressing a decades-old suggestion, it has been shown that the competition between alternative representations in BR induces a pattern of neural activation resembling that occurring in cognitive conflict, eventually leading to fluctuations between different perceptual outcomes in the case of steep competition. This is reflected by known signatures of conflict dynamics, namely, an increase in fronto-medial theta oscillatory power (5–7 Hz) in the EEG right before perceptual transitions and a decrease thereafter, as well as a decrease in parieto-occipital alpha oscillatory power (8–12 Hz) prior to perceptual transitions and an increase thereafter. However, according to a growing body of research, frontal activity during BR might be related to report processes rather than perception processing per se. Such conflation is related to the use of continuous report protocols. To circumvent this confound, here, we present a BR study using an onset rivalry (rather than continuous rivalry) protocol that dissociates the moment of report from the period of stimulus presentation. The findings revealed higher fronto-medial theta power for rivalrous than for non-rivalrous stimuli both resulting in equivalent perceptual classification, despite the absence of a motor confound. In addition, we found greater parieto-occipital alpha suppression for rivalrous stimuli. The results presented here advance our understanding of how cognitive conflict monitoring and resolution may influence perception in the event of competition from incompatible sensory patterns.

Neuroscience thrives on diversity—not only in the questions it asks but also in the models it uses to explore them. Across the field, different animal models have played pivotal roles in uncovering the principles governing brain function, development, and disease. Yet, the choice of model organisms remains a subject of debate. This editorial highlights the importance of embracing a wide range of animal models in neuroscience research. Each model offers unique strengths aligned with particular experimental approaches and scientific questions, contributing complementary insights that no single species alone can provide. By leveraging this diversity, we can achieve a more comprehensive understanding of the brain across levels of organization, from molecular pathways to behavioral outputs at the organismal level. Beyond the scientific advantages, we also discuss ethical and practical considerations: A diverse approach can promote responsible animal use by tailoring species choice to specific research goals. It can also foster environmental sustainability by avoiding unnecessary duplication of effort and resources. We call on neuroscientists to reflect on the value of integrating insights across species and experimental approaches. By moving beyond entrenched preferences and disciplinary silos, the field can unlock new opportunities for discovery. In championing the use of diverse animal models, we aim to inspire a more inclusive, efficient, and impactful neuroscience that rises to the complexity of its subject.

The human brain continuously forms predictions about the unfolding sensory environment, relying on contextual information to anticipate upcoming events while remaining sensitive to unexpected changes. This study examined how pupil-linked phasic arousal, a putative proxy for the locus coeruleus–norepinephrine system, reflects the interplay between tonal surprisal (unexpectedness) and precision (reliability of the inferred context) in dynamic auditory contexts. Twenty-eight participants passively listened to stochastic tone sequences transitioning between periods of low-entropy (informative context) and high-entropy (less informative context). We quantified tone-by-tone surprisal and precision using Bayesian modeling. Despite their slow time evolution, pupil dilation responses revealed sensitivity to both surprisal and precision, showing that arousal tracks momentary deviations and the stability of contextual predictions. Analyses of context boundaries showed that transitions between distinct low-entropy environments (LE-dLE) evoked significant pupil dilation, whereas shifts between low- and high-entropy environments (LE-HE and HE-LE) did not. These findings indicate that pupil-linked arousal primarily responds to salient contextual shifts involving stable environments rather than to changes in entropy per se. The results emphasize the role of the locus coeruleus–norepinephrine system in adaptive model updating during passive listening and demonstrate the brain's continuous and implicit monitoring of uncertainty to navigate dynamic auditory environments.

Individuals with cocaine use disorder (CUD) who attempt abstinence experience craving and relapse that can benefit from multimodal treatment monitoring. Longitudinal studies linking behavioral manifestations in CUD to the blood transcriptome are not only limited but also computationally complex. Therefore, we developed an analytical pipeline to investigate the connection between drug use behaviors during abstinence and change in the blood transcriptome. We conducted a longitudinal study with CUD (n = 12 subjects) and collected behavioral metrics and blood RNA-seq at baseline, 3, 6, and 9 months. Our analytical pipeline of the high-dimensional data encompasses hierarchical k-means clustering to classify subjects to responder groups based on behavioral scores and abstinence duration, in silico cell deconvolution, differential analysis with correlated multivariate testing over time, gene set enrichment analysis, and gene co-expression with time splines and RNA-seq data. The pipeline captured dynamic changes in behavioral scores and abstinence duration in responder groups. Genes showing differential transcript-level expression were enriched in substance use and cardiovascular disease-associated genetic risk loci in responder groups. Lastly, time-dependent gene co-expression revealed dynamic changes related to immune processes, cell cycle, RNA-protein synthesis, and second messenger signaling for days of abstinence. This is a preliminary investigation, providing an innovative and scalable pipeline for blood-based longitudinal RNA-seq studies in CUD, potentially applicable to other substance use disorders. It outlines a data-driven approach for analyzing composite longitudinal drug use behavioral phenotypes with blood-based transcriptomics. We also demonstrate changes in drug use behaviors and the blood transcriptome during drug abstinence.

Long-term memory (LTM) has been associated with neural oscillation in the theta (3-8 Hz) range. Although previous studies have suggested that the dorsomedial prefrontal cortex (dmPFC) is a core region for LTM retrieval, causal evidence is sparse and mixed. Furthermore, the moderating effects of stimulus memorability have not yet been explored. In the present study, we used transcranial alternating current stimulation (tACS) to modulate theta oscillation in the dmPFC during the retrieval of visual images with varying levels of memorability. Specifically, we included n = 33 healthy volunteers who were exposed to 300 images of faces, scenes and items, which they had to memorize. Recognition accuracy was assessed 1 h later. During the retrieval phase, participants received either sham or verum (4 Hz, 2.5 mA) tACS and were asked whether they had seen the pictures before (150 new and 150 old). Contrary to our preregistered hypotheses, we found no significant effect of 4-Hz tACS applied during retrieval on LTM recognition. Furthermore, although the memorability effect was observed, it did not interact with tACS, indicating that stimulation neither improved nor worsened performance on low- and high-memorable images. Altogether, the present study does not support an active role of 4-Hz oscillations in the dmPFC for the recognition of images with varying levels of memorability, under the specific task and stimulation parameters used here. However, this null effect may be specific to the task and particular parameters used in this study.