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Unweaving the Cognitive Map: A Personal History I have been incredibly fortunate to have worked in the field of hippocampal spatial coding during three of its most exciting decades, the 1990s, 2000s, and 2010s. During this time I had a ringside view of some of the foundational discoveries that were made which have transformed our understanding of the hippocampal system and its role in cognition (especially spatial cognition) and memory. These discoveries inspired me in my own lab over the years to pursue three broad lines of enquiry—3D spatial encoding, context and the sense of direction—which are outlined here. If some of my personal recollections are a little inaccurate (such is the nature of episodic memory!) I apologize in advance.

Adverse childhood experiences and emotion dynamics in daily life: a two sample study Research suggests that adverse childhood experiences (ACEs) can have life-long consequences on emotional functioning. However, it is unclear how ACEs shape the dynamic features of everyday emotions. In the current preregistered study with two adult ecological momentary assessment samples (Ns = 122 and 121), we examined the linear and curvilinear associations of ACEs with daily emotion dynamic features. We expected ACEs to show linear associations with a higher baseline level, variability, and inertia of negative emotions, as well as a lower baseline level of positive emotions. Moreover, we expected ACEs to show U-shaped curvilinear associations with the variability of negative and positive emotions. The results did not support our hypotheses. Instead, ACEs showed an inverted U-shaped association with the baseline level and variability of negative emotions. Furthermore, ACEs also showed a U-shaped association with the baseline level of positive emotions and a linear association with higher variability of positive emotions. However, all associations were present in only one of the two samples. Our study underscores the critical need to incorporate a broad spectrum of ACEs in research samples to adequately capture their developmental consequences and the role of ACEs in contributing to the baseline level and variability of daily emotions.

The cost of Pavlovian bias: maladaptive decision-making in human sign-trackers and goal-trackers This study examines how individual differences in Pavlovian learning profiles—specifically between sign-trackers and goal-trackers—shape maladaptive decision-making. Using a modified version of the Pavlovian-to-Instrumental Transfer (PIT) paradigm, we tested 60 participants to investigate whether sign-trackers display a stronger maladaptive Pavlovian bias in decision-making compared to goal-trackers. Both groups successfully learned optimal decision-making strategies, but sign-trackers deviated more frequently when presented with task-irrelevant, outcome-predictive cues, showing a pronounced reliance on suboptimal strategies. Computational modeling revealed that this maladaptive bias stems from slower Pavlovian cue value updating (Pavlovian α) among sign-trackers, a process further linked to their heightened incentive value attribution to cues (measured via pupil dilation). These findings provide critical insights into the computational and motivational mechanisms underlying maladaptive decision-making and support the presence of a link between sign-trackers and cognitive vulnerabilities. The results carry significant implications for understanding susceptibility to addictive behaviors and other pathologies involving maladaptive cue-driven decisions.

A gradient of hemisphere-specific dorsal to ventral processing routes in parieto-premotor network Networks in the parietal and premotor cortices enable essential human abilities regarding motor processing, including attention and tool use. Even though our knowledge on its topography has steadily increased, a detailed picture of hemisphere-specific integrating pathways is still lacking. With the help of multishell diffusion magnetic resonance imaging, probabilistic tractography, and the Graph Theory Analysis, we investigated connectivity patterns between frontal premotor and posterior parietal brain areas in healthy individuals. With a two-stage node characterization approach, we defined the network role of precisely mapped cortical regions from the Julich-Brain atlas. We found evidence for a third, left-sided, medio-dorsal subpathway in a successively graded dorsal stream, referencing more specialized motor processing on the left. Supplementary motor areas had a strongly lateralized connectivity to either left dorsal or right ventral parietal domains, representing an action-attention dichotomy between hemispheres. The left sulcal parietal regions primarily coupled with areas 44 and 45, mirrored by the inferior frontal junction (IFJ) on the right, a structural lateralization we termed as “Broca’s-IFJ switch.” We were able to deepen knowledge on gyral and sulcal pathways as well as domain-specific contributions in parieto-premotor networks. Our study sheds new light on the complex lateralization of cortical routes for motor activity in the human brain.

Neonatal Brain Injury Triggers Niche-Specific Changes to Cellular Biogeography Preterm infants are at risk for brain injury and neurodevelopmental impairment due, in part, to white matter injury following chronic hypoxia exposure. However, the precise molecular mechanisms by which neonatal hypoxia disrupts early neurodevelopment are poorly understood. Here, we constructed a brain-wide map of the regenerative response to newborn brain injury using high-resolution imaging-based spatial transcriptomics to analyze over 800,000 cells in a mouse model of chronic neonatal hypoxia. Additionally, we developed a new method for inferring condition-associated differences in cell type spatial proximity, enabling the identification of niche-specific changes in cellular architecture. We observed hypoxia-associated changes in region-specific cell states, cell type composition, and spatial organization. Importantly, our analysis revealed mechanisms underlying reparative neurogenesis and gliogenesis, while also nominating pathways that may impede circuit rewiring following neonatal hypoxia. Altogether, our work provides a comprehensive description of the molecular response to newborn brain injury.

Right middle occipital gyrus is associated with egocentric spatial orientation during body tilt: Evidence from a repetitive transcranial magnetic stimulation study Accurate perception of the orientation of external objects relative to the body, known as egocentric spatial orientation, is fundamental to performing action. Previously, we found via behavioural and magnetic resonance imaging voxel-based morphometry studies that egocentric spatial orientation is strongly distorted when the whole body is tilted with respect to gravity, and that the magnitude of this perceptual distortion is correlated with the grey matter volume of the right middle occipital gyrus (rMOG). In the present study, we further validated the association between the neural processing in the rMOG and the perceptual distortion by transiently suppressing neural activity in this region using low-frequency repetitive transcranial magnetic stimulation (rTMS) and evaluating the consequent effect on perceptual distortion. Our results showed that rTMS over the rMOG significantly reduced perceptual distortions when the body was tilted in the frontal plane, while it did not affect egocentric spatial orientation in the upright position. No significant changes in perceptual distortion were observed when rTMS was applied to another cortical candidate (the right temporo-parietal junction). These results provide evidence that neural processing in the rMOG is associated with body tilt-related perceptual distortion, suggesting that the rMOG may be engaged in egocentric spatial orientation related to gravitational information.

Associations between Genetic Variations in Oxytocin Pathway Genes and Hippocampal Volume: Insights from the UK Biobank The role of oxytocin-related genes in social-cognitive function has been previously established, but structural brain mechanisms underlying this link remain poorly understood. Utilizing a substantial dataset from the UK Biobank (N ≈ 30,000), this research determined associations between variations in ten single nucleotide polymorphisms (SNPs) within three oxytocin pathway genes (i.e., the oxytocin/neurophysin I prepropetide gene, the cluster of differentiation 38 glycoprotein gene, the oxytocin receptor gene) and whole-brain gray matter volume. Carriers of the AA or AG genotypes of the oxytocin receptor gene rs237851 SNP exhibited significantly larger hippocampal volume than carriers of the GG genotype. These results support the link between variations in the oxytocin receptor gene and hippocampal structure, with possible impact on social-cognitive function such as social recognition memory.

PEL 3357: Feuerbach on the Evolution of Philosophy (Part One) We’re continuing to look at Ludwig Feuerbach’s essay “Principles of the Philosophy of the Future” (1843). Now past his critique of theology in our last episode, Mark, Wes, and Dylan address F’s account of the history of philosophy from theism to pantheism to idealism to Hegelianism, and finally to F’s own “philosophy of the future,” which is a materialism that naturally flows out as the correction of Hegel’s system.

In a very Hegelian manner, F posits each of these stages as a corrective on the preceding. If traditional theologians really understood what they were doing and wanted to make their notion of God as all-encompassing consistent, then they’d make it include nature a la Spinoza’s pantheism. If Spinoza really knew what he was doing, then he’d have incorporated Hegel’s insight that God should be the Subject of experience and not just a special kind of object that has mentality as one of its aspects. And if Hegel really knew what he was doing, he’d realize that by making matter itself part of an all-encompassing Subject, then you’ve removed the distinction between matter and mind and should instead of calling the whole system Spirit (mind), just acknowledge that you’re talking fundamentally about matter: God (i.e. everything) is material, or more precisely sensual.

He doesn’t want to define matter a la Descartes as essentially extension, as this would be an abstraction. Matter is instead whatever it is that we sense in its wholeness on a daily basis, including things like love. Feuerbach doesn’t really explain what this means metaphysically, e.g. for the philosophy of mind (How are “ideas” matter? Because they’re brain states?). He does make it clear that there must be real multiplicity for relationships (e.g. between God and creation) to be meaningful; God can’t just be thinking Himself as is the case on Hegel’s account. If when a mind grasps some bit of matter, it’s just mind grasping mind, then the whole thing would lack reality, vanishing in metaphysical smoke.

Feuerbach’s sensual “philosophy of the future” strikes us as proto-phenomenological, in that the world that our senses take in is not the bare appearances of empiricists like Locke and Hume (e.g. a swatch of red), but is more holistic, including cultural matters. We sense (experience) the world as included and shaped by other people, nature as a home. We do not just experience sense-data and have to make conclusions about the real existence of entities causing those data, but we experience real entities in the a world that we are inextricably embedded in (yes, F prefigures Heidegger’s being-in-the-world).