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The lateral entorhinal cortex (LEC) and medial entorhinal cortex (MEC) are the two major cortical projections to the hippocampus. The discovery of a variety of functional cell types in MEC has greatly advanced our understanding of the functional anatomy of entorhinal-hippocampal circuits. However, the function of LEC and the behavioral correlates of LEC cells are still not fully understood. Wang et al. analyzed the firing properties of LEC and MEC neurons. They found that LEC and MEC used different reference frames, with LEC encoding objects egocentrically. Science , this issue p. 945 The lateral entorhinal cortex represents salient items in the environment in a self-referential framework. Episodic memory, the conscious recollection of past events, is typically experienced from a first-person (egocentric) perspective. The hippocampus plays an essential role in episodic memory and spatial cognition. Although the allocentric nature of hippocampal spatial coding is well understood, little is known about whether the hippocampus receives egocentric information about external items. We recorded in rats the activity of single neurons from the lateral entorhinal cortex (LEC) and medial entorhinal cortex (MEC), the two major inputs to the hippocampus. Many LEC neurons showed tuning for egocentric bearing of external items, whereas MEC cells tended to represent allocentric bearing. These results demonstrate a fundamental dissociation between the reference frames of LEC and MEC neural representations.

Cell assembly sequences during learning are \"replayed\" during hippocampal ripples and contribute to the consolidation of episodic memories. However, neuronal sequences may also reflect preexisting dynamics. We report that sequences of place-cell firing in a novel environment are formed from a combination of the contributions of a rigid, predominantly fast-firing subset of pyramidal neurons with low spatial specificity and limited change across sleep-experience-sleep and a slow-firing plastic subset. Slow-firing cells, rather than fast-firing cells, gained high place specificity during exploration, elevated their association with ripples, and showed increased bursting and temporal coactivation during postexperience sleep. Thus, slow- and fast-firing neurons, although forming a continuous distribution, have different coding and plastic properties.

Grid cells with their rigid hexagonal firing fields are thought to provide an invariant metric to the hippocampal cognitive map, yet environmental geometrical features have recently been shown to distort the grid structure. Given that the hippocampal role goes beyond space, we tested the influence of nonspatial information on the grid organization. We trained rats to daily learn three new reward locations on a cheeseboard maze while recording from the medial entorhinal cortex and the hippocampal CA1 region. Many grid fields moved toward goal location, leading to long-lasting deformations of the entorhinal map. Therefore, distortions in the grid structure contribute to goal representation during both learning and recall, which demonstrates that grid cells participate in mnemonic coding and do not merely provide a simple metric of space.

Which brain regions are causally involved in reward-related behavior? Ferenczi et al. combined focal, cell type-specific, optogenetic manipulations with brain imaging, behavioral testing, and in vivo electrophysiology (see the Perspective by Robbins). Stimulation of midbrain dopamine neurons increased activity in a brain region called the striatum and was correlated with reward-seeking across individual animals. However, elevated excitability of an area called the medial prefrontal cortex reduced both striatal responses to the stimulation of dopamine neurons and the behavioral drive to seek the stimulation of dopamine neurons. Finally, modulating the excitability of medial prefrontal cortex pyramidal neurons drove changes in neural circuit synchrony, as well as corresponding anhedonic behavior. These observations resemble imaging and clinical phenotypes observed in human depression, addiction, and schizophrenia. Science , this issue p. 10.1126/science.aac9698 ; see also p. 10.1126/science.aad9698 Optogenetic and brain imaging approaches reveal a causal brainwide dynamical mechanism for the hedonic-anhedonic transition. [Also see Perspective by Robbins ] Motivation for reward drives adaptive behaviors, whereas impairment of reward perception and experience (anhedonia) can contribute to psychiatric diseases, including depression and schizophrenia. We sought to test the hypothesis that the medial prefrontal cortex (mPFC) controls interactions among specific subcortical regions that govern hedonic responses. By using optogenetic functional magnetic resonance imaging to locally manipulate but globally visualize neural activity in rats, we found that dopamine neuron stimulation drives striatal activity, whereas locally increased mPFC excitability reduces this striatal response and inhibits the behavioral drive for dopaminergic stimulation. This chronic mPFC overactivity also stably suppresses natural reward-motivated behaviors and induces specific new brainwide functional interactions, which predict the degree of anhedonia in individuals. These findings describe a mechanism by which mPFC modulates expression of reward-seeking behavior, by regulating the dynamical interactions between specific distant subcortical regions.

The mechanism by which psychological stress elicits various physiological responses is unknown. We discovered a central master neural pathway in rats that drives autonomic and behavioral stress responses by connecting the corticolimbic stress circuits to the hypothalamus. Psychosocial stress signals from emotion-related forebrain regions activated a VGLUT1-positive glutamatergic pathway from the dorsal peduncular cortex and dorsal tenia tecta (DP/DTT), an unexplored prefrontal cortical area, to the dorsomedial hypothalamus (DMH), a hypothalamic autonomic center. Genetic ablation and optogenetics revealed that the DP/DTT→DMH pathway drives thermogenic, hyperthermic, and cardiovascular sympathetic responses to psychosocial stress without contributing to basal homeostasis. This pathway also mediates avoidance behavior from psychosocial stressors. Given the variety of stress responses driven by the DP/DTT→DMH pathway, the DP/DTT can be a potential target for treating psychosomatic disorders.

In plants, somatic embryo development is regulated by a complex group or network of transcription factors (TFs). The LEAFY COTYLEDON (LEC) TFs are significant key regulators that promote the initiation of somatic embryo formation and biological processes of the embryo maturation phase. The LEC gene has been implicated to act as unique regulators in plant embryogenesis, growth and development via diverse signaling pathways. In the present review, we summarize the current advances in our understanding of the LEC TFs in plant biology including embryogenesis. Recent discoveries would be advantageous to unlock the mysteries of LEC TF genes of different molecular mechanisms in plant cells.

Successful movement depends on an accurate sense of one's location within a particular environment. Neuroscientists distinguish self-centered and world-centered navigation and have been searching for a brain region where all ingredients of navigation come together. As rats foraged in an open field, LaChance et al. recorded activity from single neurons in an area called the postrhinal cortex. The authors found a population of cells that transform an animal's immediate sensory perception of its environment into a spatial map. This map is markedly different from the high-level representations observed in hippocampal place cells or entorhinal grid cells, but it is very flexible and is likely to provide the necessary building blocks for creating higher-level representations. Science , this issue p. eaax4192 Neurons in the rat postrhinal cortex provide a template for the formation of high-level topographic spatial maps. A topographic representation of local space is critical for navigation and spatial memory. In humans, topographic spatial learning relies upon the parahippocampal cortex, damage to which renders patients unable to navigate their surroundings or develop new spatial representations. Stable spatial signals have not yet been observed in its rat homolog, the postrhinal cortex. We recorded from single neurons in the rat postrhinal cortex whose firing reflects an animal’s egocentric relationship to the geometric center of the local environment, as well as the animal’s head direction in an allocentric reference frame. Combining these firing correlates revealed a population code for a stable topographic map of local space. This may form the basis for higher-order spatial maps such as those seen in the hippocampus and entorhinal cortex.

Typhoons pose significant safety threats to coastal university campuses, causing injuries due to tree collapse and falling branches each year. This study develops a risk assessment model for campus pedestrian routes during typhoons using the LEC (Likelihood, Exposure, Consequence) method with a normalization algorithm, validated through a case study at Shantou University. Through field surveys, CFD wind simulations, space syntax analysis, and tree risk classification, we assessed 38 road sections across three major travel routes. Results reveal significant spatial variations in risk levels, with high-risk sections concentrated in open areas and near high-hazard tree species. Route optimization strategies are proposed to enhance safety and resilience. The research provides a practical framework for improving typhoon risk management on coastal university campuses, supporting the development of climate-adaptive and resilient campus spaces.

The hippocampal cognitive map is thought to be driven by distal visual cues and self-motion cues. However, other sensory cues also influence place cells. Hence, we measured rat hippocampal activity in virtual reality (VR), where only distal visual and nonvestibular self-motion cues provided spatial information, and in the real world (RW). In VR, place cells showed robust spatial selectivity; however, only 20% were track active, compared with 45% in the RW. This indicates that distal visual and nonvestibular self-motion cues are sufficient to provide selectivity, but vestibular and other sensory cues present in RW are necessary to fully activate the place-cell population. In addition, bidirectional cells preferentially encoded distance along the track in VR, while encoding absolute position in RW. Taken together, these results suggest the differential contributions of these sensory cues in shaping the hippocampal population code. Theta frequency was reduced, and its speed dependence was abolished in VR, but phase precession was unaffected, constraining mechanisms governing both hippocampal theta oscillations and temporal coding. These results reveal cooperative and competitive interactions between sensory cues for control over hippocampal spatiotemporal selectivity and theta rhythm.

Computational and learning theory models propose that behavioral control reflects value that is both cached (computed and stored during previous experience) and inferred (estimated on the fly on the basis of knowledge of the causal structure of the environment). The latter is thought to depend on the orbitofrontal cortex. Yet some accounts propose that the orbitofrontal cortex contributes to behavior by signaling \"economic\" value, regardless of the associative basis of the information. We found that the orbitofrontal cortex is critical for both value-based behavior and learning when value must be inferred but not when a cached value is sufficient. The orbitofrontal cortex is thus fundamental for accessing model-based representations of the environment to compute value rather than for signaling value per se.