European Journal of Neuroscience最新文献

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.

Perceptual decisions are shaped by recent stimulus and response history, yet these history effects vary with experimental design and task structure. Their origins, the processing stages involved, the factors that determine their magnitude and the sources of individual differences require further investigation. We propose a multisensory approach that leverages cross-modal transfer of history effects as a diagnostic tool to address these open questions. Visual-vestibular stimuli are particularly suitable because both modalities contribute to estimating the body's position in space and they likely share central processing stages. This approach allows for manipulation of response format, independently of sensory stimulation. By moving beyond isolated sensory channels and examine perceptual decisions as they occur in everyday multisensory environments, we provide a framework to investigate when, how and why recent history shapes perception.

Previous studies of verbal working memory (WM) have reported inconsistent changes in alpha power during retention, with both increases and decreases observed. We asked whether these discrepancies arise from how stimuli are presented. Thirty adults memorized seven digits presented in four modes: Simultaneous (all digits for 2800 ms) or sequential presentations at Fast (400 ms per digit), Slow (1000 ms per digit), and Fast + delay (400 ms per digit plus a 600-ms free time in between). We analyzed EEG during encoding and a 6-s retention period in theta (4–7 Hz), alpha (8–13 Hz), and beta (18–24 Hz) frequency bands. Encoding produced parametric load-related theta increase and beta decrease, possibly reflecting growing executive control demands and motor program formation, respectively. Alpha power did not scale with load during encoding. Single trial models linked stronger encoding theta and deeper alpha suppression to better recall, whereas retention power did not predict accuracy. During retention, theta and beta were unaffected by presentation mode. Alpha power did not differ significantly when all sequential modes were grouped together compared to the simultaneous mode. However, the Fast + delay mode uniquely showed below-baseline alpha in the first half of the retention. Our findings suggest that alpha dynamics are sensitive to the temporal structure of encoding and retention periods, particularly the presence or absence of free intervals between stimulus presentations. We propose that alpha modulation during WM retention may reflect processes beyond the simple gating of irrelevant sensory information.