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Summary: DISC1 is a genetic risk factor for multiple psychiatric disorders. Compared to the dozens of murine Disc1 models, there is a paucity of zebrafish disc1 models—an organism amenable to high-throughput experimentation. We conducted the longitudinal neurobehavioral analysis of disc1 mutant zebrafish across key stages of life. During early developmental stages, disc1 mutants exhibited abrogated behavioral responses to sensory stimuli across multiple testing platforms. Moreover, during exposure to an acoustic sensory stimulus, loss of disc1 resulted in the abnormal activation of neurons in the pallium, cerebellum, and tectum—anatomical sites involved in the integration of sensory perception and motor control. In adulthood, disc1 mutants exhibited sexually dimorphic reduction in anxiogenic behavior in novel paradigms. Together, these findings implicate disc1 in sensorimotor processes and the genesis of anxiogenic behaviors, which could be exploited for the development of novel treatments in addition to investigating the biology of sensorimotor transformation in the context of disc1 deletion.

Summary: The functional role of heterogeneous spiking responses of otherwise similarly tuned neurons to stimulation, which has been observed ubiquitously, remains unclear to date. Here, we demonstrate that such response heterogeneity serves a beneficial function that is used by downstream brain areas to generate behavioral responses that follows the detailed timecourse of the stimulus. Multi-unit recordings from sensory pyramidal cells within the electrosensory system of Apteronotus leptorhynchus were performed and revealed highly heterogeneous responses that were similar for all cell types. By comparing the coding properties of a given neural population before and after inactivation of descending pathways, we found that heterogeneities were beneficial as decoding was then more robust to the addition of noise. Taken together, our results not only reveal that descending pathways actively promote response heterogeneity within a given cell type, but also uncover a beneficial function for such heterogeneity that is used by the brain to generate behavior.

Summary: The thalamus and cortex are anatomically interconnected, with the thalamus providing integral information for cortical functions. The anteroventral thalamic nucleus (AV) is reciprocally connected to retrosplenial cortex (RSC). Two distinct AV subfields, dorsomedial (AVDM) and ventrolateral (AVVL), project differentially to granular vs. dysgranular RSC, respectively. To probe if functional responses of AV neurons differ, we recorded single neurons and local field potentials from AVDM and AVVL in rats during foraging. We observed place cells (neurons modulated by spatial location) in both AVDM and AVVL. Additionally, we characterized neurons modulated by theta oscillations, heading direction, and a conjunction of these. Place cells and conjunctive Theta-by-Head direction cells were more prevalent in AVVL; more non-conjunctive theta and directional neurons were prevalent in AVDM. These findings add further evidence that there are two thalamocortical circuits connecting AV and RSC, and reveal that the signaling involves place information in addition to direction and theta.

Summary: The structure and function of the cardiovascular system are modulated across the day by circadian rhythms, making this system susceptible to circadian rhythm disruption. Recent evidence demonstrated that short-term exposure to a pervasive circadian rhythm disruptor, artificial light at night (ALAN), increased inflammation and altered angiogenic transcripts in the hippocampi of mice. Here, we examined the effects of four nights of ALAN exposure on mouse hippocampal vascular networks. To do this, we analyzed 2D and 3D images of hippocampal vasculature and hippocampal transcriptomic profiles of mice exposed to ALAN. ALAN reduced vascular density in the CA1 and CA2/3 of female mice and the dentate gyrus of male mice. Network structure and connectivity were also impaired in the CA2/3 of female mice. These results demonstrate the rapid and potent effects of ALAN on cerebrovascular networks, highlighting the importance of ALAN mitigation in the context of health and cerebrovascular disease.

Summary: Early identification of neurodevelopmental disorders is important to ensure a prompt and effective intervention, thus improving the later outcome. Autism spectrum disorder (ASD) and language learning impairment (LLI) are among the most common neurodevelopmental disorders, and they share overlapping symptoms. This study aims to characterize baseline electroencephalography (EEG) spectral power in 6- and 12-month-old infants at higher likelihood of developing ASD and LLI, compared to typically developing infants, and to preliminarily verify if spectral power components associated with the risk status are also linked with the later ASD or LLI diagnosis. We found risk status for ASD to be associated with reduced power in the low-frequency bands and risk status for LLI with increased power in the high-frequency bands. Interestingly, later diagnosis shared similar associations, thus supporting the potential role of EEG spectral power as a biomarker useful for understanding pathophysiology and classifying diagnostic outcomes.

The Food Finding Test (FFT) olfactory paradigm without overnight food deprivation examined olfaction in aged (16-months-old) animals. Ethograms of three goal-directed behaviors towards hidden food (sniffing, finding and eating) elicited in male and female 3xTg-AD mice for Alzheimer’s disease (AD) and their age-matched C57BL/6 wild-type counterparts with normal aging were meticulously analyzed with the support of video recordings. The new FFT protocol elicited longer ethograms than previously reported with the standard deprivation protocol. However, it was sensitive when identifying genotype- and sex-dependent olfactory signatures for the temporal patterns of slow sniffing, finding, and eating in AD and males, but it had a striking consistency in females. The impact of forced social isolation was studied and it was found to exert sex-dependent modifications of the ethogram, mostly in males. Still, in both sexes, a functional derangement was detected since the internal correlations among the behaviors decreased or were lost under isolated conditions. In conclusion, the new paradigm without overnight deprivation was sensitive to sex (males), genotype (AD), and social context (isolation-dependent changes) in its ethogram and functional correlation. At the translational level, it is a warning about the impact of isolation in the advanced stages of the disease, paying notable attention to the male sex.

This document is an editorial published in Frontiers in Behavioral Neuroscience titled "Improving reproducibility in behavioral neuroscience." The authors discuss the importance of reproducibility in scientific research, particularly in the field of behavioral neuroscience. They highlight the ethical implications of a lack of reproducibility and the potential waste of animal lives in research. The authors suggest that combining principles of animal welfare with experimental rigor can help combat the reproducibility crisis. They also discuss specific measures and procedures that the scientific community should adopt to improve the reliability and translational potential of pre-clinical research. [Extracted from the article]

This article is an editorial published in Frontiers in Behavioral Neuroscience titled "Neurobiology of food addiction." The editorial discusses the concept of food addiction and its increasing academic interest in recent years. It explores the parallels between food-related behaviors and substance use disorders, as well as the use of the term "food addiction" and its classification as a disorder. The editorial also highlights different aspects of the neurobiology and behavior related to food addiction, including genetic and epigenetic alterations, cue-guided decision-making, and the role of the olfactory system. Overall, the article provides valuable insights into the mechanisms underlying addictive behaviors and offers potential avenues for future studies and prevention strategies. [Extracted from the article]

This document is an editorial titled "New challenges and future perspectives in motivation and reward" published in the journal Frontiers in Behavioral Neuroscience. The authors discuss the importance of motivation in our daily lives and its role in driving behaviors. They explore the interaction between motivation and reward or aversion and how it influences learning. The editorial also provides a summary of key findings from several articles published in the same research topic, including studies on the effects of stress and impulsivity on binge drinking, the relationship between motor impulsivity and drug-seeking behaviors, and the role of ultrasonic vocalizations in feeding behaviors. Overall, the articles contribute to our understanding of the neural basis of motivation and reward. [Extracted from the article]

Information coding is generally thought to emerge from fast activity across thousands of neurons. A recent study shows that many features of a sophisticated decision-action sequence are encoded by the slow activity of individual command neurons. [ABSTRACT FROM AUTHOR]

This document is a corrigendum for an article titled "L-DOPA increases slow-wave sleep duration and selectively modulates memory persistence in older adults." The corrigendum acknowledges an error in the funding statement of the original article, where the Doctoral Training Grant number was omitted. The correct funding statement is provided, and it is stated that this error does not affect the scientific conclusions of the article. The corrigendum also includes a note from the publisher stating that the claims expressed in the article are solely those of the authors and do not necessarily represent the views of their affiliated organizations or the publisher. [Extracted from the article]

This document is an editorial published in Frontiers in Behavioral Neuroscience. It discusses the complex interrelations and challenges in the diagnosis and treatment of neurological and psychiatric disorders. The editorial highlights four key studies that focus on innovative strategies and emerging trends in managing conditions such as Parkinson's Disease, Tourette Syndrome, Bipolar Spectrum Disorders, and Multiple Sclerosis. The studies explore the effectiveness of mind-body exercises in mitigating cognitive decline in Parkinson's patients, the need for enhanced international cooperation in Tourette Syndrome research, the intersections between Bipolar Spectrum Disorders and neurological disorders, and the social cognition deficits in Multiple Sclerosis. The editorial emphasizes the importance of integrative approaches, collaborative efforts, and personalized care in addressing these disorders and improving the quality of life for individuals affected by them. [Extracted from the article]

This article, titled "Editorial: Computer vision and human behaviour to recognize emotions," explores the intersection of computer vision and human behavior in recognizing emotions. The authors discuss the potential of computer vision to automate tasks related to understanding emotions and human behavior. The article includes studies that compare facial emotion recognition systems, investigate emotion recognition by humans and machines, and explore facial emotion recognition in virtual reality environments. The authors emphasize the importance of responsible development and deployment of emotion recognition systems to ensure reliability, fairness, and privacy. [Extracted from the article]

Summary: The insular cortex (insula) is known to play a modulatory role in feeding and drinking. Previous studies have revealed anterior-posterior differences of subcortical projections and roles for the insula, yet the anatomical and functional heterogeneity among the cortical layers remains poorly understood. Here, we show that layer 5 of the mouse dysgranular insula has two distinct neuronal subpopulations along the entire anterior-posterior axis: The L5a population, expressing NECAB1, projects bilaterally to the lateral and capsular divisions of the central amygdala, and the L5b population, expressing CTIP2, projects ipsilaterally to the parasubthalamic nucleus and the medial division of the central amygdala. Optogenetically activating L5a and L5b neuronal populations in thirsty male mice led to suppressed and facilitated water spout licking, respectively, without avoidance against or preference for the spout paired with the opto-stimulation. Our results suggest sublayer-specific bidirectional modulatory roles of insula layer 5 in the motivational aspect of appetitive behavior.

Summary: Selective attention modulates the neural tracking of speech in auditory cortical regions. It is unclear whether this attentional modulation is dominated by enhanced target tracking, or suppression of distraction. To settle this long-standing debate, we employed an augmented electroencephalography (EEG) speech-tracking paradigm with target, distractor, and neutral streams. Concurrent target speech and distractor (i.e., sometimes relevant) speech were juxtaposed with a third, never task-relevant speech stream serving as neutral baseline. Listeners had to detect short target repeats and committed more false alarms originating from the distractor than from the neutral stream. Speech tracking revealed target enhancement but no distractor suppression below the neutral baseline. Speech tracking of the target (not distractor or neutral speech) explained single-trial accuracy in repeat detection. In sum, the enhanced neural representation of target speech is specific to processes of attentional gain for behaviorally relevant target speech rather than neural suppression of distraction.

Summary: Neurological complications that occur in SARS-CoV-2 infection, such as olfactory dysfunction, brain inflammation, malaise, and depressive symptoms, are thought to contribute to long COVID. However, in autopsies of patients who have died from COVID-19, there is normally no direct evidence that central nervous system damage is due to proliferation of SARS-CoV-2. For this reason, many aspects of the pathogenesis mechanisms of such symptoms remain unknown. Expressing SARS-CoV-2 S1 protein in the nasal cavity of mice was associated with increased apoptosis of the olfactory system and decreased intracerebral acetylcholine production. The decrease in acetylcholine production was associated with brain inflammation, malaise, depressive clinical signs, and decreased expression of the cytokine degrading factor ZFP36. Administering the cholinesterase inhibitor donepezil to the mice improved brain inflammation, malaise and depressive clinical signs. These findings could contribute to the elucidation of the pathogenesis mechanisms of neurological complications associated with COVID-19 and long COVID.

Summary: T2R bitter receptors, encoded by Tas2r genes, are not only critical for bitter taste signal transduction but also important for defense against bacteria and parasites. However, little is known about whether and how Tas2r gene expression are regulated. Here, we show that in an inflammation model mimicking bacterial infection using lipopolysaccharide, the expression of many Tas2rs was significantly upregulated and mice displayed markedly increased neural and behavioral responses to bitter compounds. Using single-cell assays for transposase-accessible chromatin with sequencing (scATAC-seq), we found that the chromatin accessibility of Tas2rs was highly celltype specific and lipopolysaccharide increased the accessibility of many Tas2rs. scATAC-seq also revealed substantial chromatin remodeling in immune response genes in taste tissue stem cells, suggesting potential long-lasting effects. Together, our results suggest an epigenetic mechanism connecting inflammation, Tas2r gene regulation, and altered bitter taste, which may explain heightened bitter taste that can occur with infections and cancer treatments.

Summary: Alzheimer’s disease (AD) is characterized by memory impairments and age-dependent synapse loss. Experimental and clinical studies have shown decreased expression of the glutamatergic protein Neuroligin-1 (Nlgn1) in AD. However, the consequences of a sustained reduction of Nlgn1 are unknown. Here, we generated a knockin mouse that reproduces the NLGN1 Thr271fs mutation, identified in heterozygosis in a familial case of AD. We found that Nlgn1 Thr271fs mutation abolishes Nlgn1 expression in mouse brain. Importantly, heterozygous Nlgn1 Thr271fs mice showed delay-dependent amnesia for recognition memory. Electrophysiological recordings uncovered age-dependent impairments in basal synaptic transmission and long-term potentiation (LTP) in CA1 hippocampal neurons of heterozygous Nlgn1 Thr271fs mice. In contrast, homozygous Nlgn1 Thr271fs mice showed impaired fear-conditioning memory and normal basal synaptic transmission, suggesting unshared mechanisms for a partial or total loss of Nlgn1. These data suggest that decreased Nlgn1 may contribute to the synaptic and memory deficits in AD.

Summary: Motor responses to visual stimuli have shorter latencies for controlling than for initiating movement. The shorter latencies observed for movement control are notably believed to reflect the involvement of forward models when controlling moving limbs. We assessed whether controlling a moving limb is a “requisite” to observe shortened response latencies. The latency of button-press responses to a visual stimulus was compared between conditions involving or not involving the control of a moving object, but never involving any actual control of a body segment. When the motor response controlled a moving object, response latencies were significantly shorter and less variable, probably reflecting a faster sensorimotor processing (as assessed fitting a LATER model to our data). These results suggest that when the task at hand entails a control component, the sensorimotor processing of visual information is hastened, and this even if the task does not require to actually control a moving limb.

Summary: In competitive matches, strategic decisions and emotional control are important. Relevant cognitive functions and corresponding neural activities in simple and short-term laboratory tasks have been reported. Brain resources are intensively allocated in the frontal cortex during strategic decision-making. The suppression of the frontal cortex with alpha-synchronization optimizes emotional control. However, no studies have reported the contribution of neural activity to the outcome of a more complex and prolonged task. To clarify this issue, we focused on a fighting video game following a two-round first-pass system. Frontal high-gamma and alpha power in the first and third pre-round periods, respectively, were found to be increased in a winning match. Furthermore, inter-participant variations in the importance of strategic decisions and emotional control in the first and third pre-round periods were correlated with frontal high-gamma and alpha power, respectively. Therefore, the psychological and mental state, involving frontal neural fluctuations, is predictive of match outcome.

Summary: Dysregulations in cholesterol metabolism are associated with neurodegenerative and vascular pathologies, and dementia. Diet-derived plant sterols (phytosterols) have cholesterol-lowering, anti-inflammatory, and antioxidant properties and may interfere with neurodegeneration and cognitive decline. Here we performed multivariate analysis in 720 individuals enrolled in a population-based prospective study to determine whether circulating cholesterol precursors and metabolites, triglycerides, and phytosterols, are associated with cognitive impairment and decline in the older population. We report specific dysregulations of endogenous cholesterol synthesis and metabolism, and diet-derived phytosterols, and their changes over time associated with cognitive impairment, and decline in the general population. These findings suggest circulating sterols levels could be considered in risk evaluation and are relevant for the development of strategies to prevent cognitive decline in older people.

Summary: Motor chunking is important for motor execution, allowing atomization and efficiency of movement sequences. However, it remains unclear why and how chunks contribute to motor execution. To analyze the structure of naturally occurring chunks, we trained mice to run in a complex series of steps and identified the formation of chunks. We found that intervals (cycle) and the positional relationship between the left and right limbs (phase) of steps inside the chunks, unlike those outside the chunks, were consistent across occurrences. Further, licking by the mice was also more periodic and linked to the specific phases of limb movements within the chunk. Based on these findings, we propose the rhythm chunking hypothesis, whereby within chunks, the repetitive movements of many body parts are linked by the rhythm parameters: cycle and phase. The computational complexity of movement may thereby be reduced by adjusting movements as the combination of rhythms.

Summary: Foraging in animals relies on innate decision-making heuristics that can result in suboptimal cognitive biases in some contexts. The mechanisms underlying these biases are not well understood, but likely involve strong genetic effects. To explore this, we studied fasted mice using a naturalistic foraging paradigm and discovered an innate cognitive bias called “second-guessing.” This involves repeatedly investigating an empty former food patch instead of consuming available food, which hinders the mice from maximizing feeding benefits. The synaptic plasticity gene Arc is revealed to play a role in this bias, as Arc-deficient mice did not exhibit second-guessing and consumed more food. In addition, unsupervised machine learning decompositions of foraging identified specific behavior sequences, or “modules”, that are affected by Arc. These findings highlight the genetic basis of cognitive biases in decision making, show links between behavior modules and cognitive bias, and provide insight into the ethological roles of Arc in naturalistic foraging.

Summary: Emerging studies demonstrate that inflammation plays a crucial role in the pathogenesis of bipolar disorder (BD), but the underlying mechanism remains largely unclear. Given the complexity of BD pathogenesis, we performed high-throughput multi-omic profiling (metabolomics, lipidomics, and transcriptomics) of the BD zebrafish brain to comprehensively unravel the molecular mechanism. Our research proved that in BD zebrafish, JNK-mediated neuroinflammation altered metabolic pathways involved in neurotransmission. On one hand, disturbed metabolism of tryptophan and tyrosine limited the participation of the monoamine neurotransmitters serotonin and dopamine in synaptic vesicle recycling. On the other hand, dysregulated metabolism of the membrane lipids sphingomyelin and glycerophospholipids altered the synaptic membrane structure and neurotransmitter receptors (chrnα7, htr1b, drd5b, and gabra1) activity. Our findings revealed that disturbance of serotonergic and dopaminergic synaptic transmission mediated by the JNK inflammatory cascade was the key pathogenic mechanism in a zebrafish model of BD, provides critical biological insights into the pathogenesis of BD.

Summary: Personality in pets and other domesticated animals is important for their well-being and it can also influence human-animal relationships. Genetic and environmental factors influencing unwanted behavior in dogs are somewhat well known, but the factors influencing dog personality remain understudied. Here we examined environmental and demographic factors associated with seven broad personality traits in a survey of over 11,000 dogs. We utilized linear models and extensive model validation to examine the factors that have the most significant influences on personality and calculated effect sizes to assess the importance of these variables. Breed and age had the strongest associations with dog personality traits. Some environmental factors, especially puppyhood socialization, were also associated with personality. All factors had small effect sizes, highlighting that a lot of variation in personality remains unexplained. Our results indicate that personality traits are complex and strikingly similar in dogs, humans, and other nonhuman animals.

Summary: Social learning is found in many animals, but its mechanisms are not understood. We previously showed that a cricket that was trained to observe a conspecific staying at a drinking apparatus exhibited an increased preference for the odor of that drinking apparatus. Here we investigated a hypothesis that this learning is achieved by second-order conditioning (SOC), i.e., by associating conspecifics at a drinking bottle with water reward during group drinking in the rearing stage and then associating an odor with a conspecific in training. Injection of an octopamine receptor antagonist before training or testing impaired the learning or response to the learned odor, as we reported for SOC, thereby supporting the hypothesis. Notably, the SOC hypothesis predicts that octopamine neurons that respond to water in the group-rearing stage also respond to a conspecific in training, without the learner itself drinking water, and such mirror-like activities mediate social learning. This awaits future investigation.

Summary: Humans can quickly adapt their behavior to changes in the environment. Classical reversal learning tasks mainly measure how well participants can disengage from a previously successful behavior but not how alternative responses are explored. Here, we propose a novel 5-choice reversal learning task with alternating position-reward contingencies to study exploration behavior after a reversal. We compare human exploratory saccade behavior with a prediction obtained from a neuro-computational model of the basal ganglia. A new synaptic plasticity rule for learning the connectivity between the subthalamic nucleus (STN) and external globus pallidus (GPe) results in exploration biases to previously rewarded positions. The model simulations and human data both show that during experimental experience exploration becomes limited to only those positions that have been rewarded in the past. Our study demonstrates how quite complex behavior may result from a simple sub-circuit within the basal ganglia pathways.

Summary: In internal fertilization animals, reproductive success depends on maintaining copulation until gametes are transported from male to female. In Drosophila melanogaster, mechanosensation in males likely contributes to copulation maintenance, but its molecular underpinning remains to be identified. Here we show that the mechanosensory gene piezo and its’ expressing neurons are responsible for copulation maintenance. An RNA-seq database search and subsequent mutant analysis revealed the importance of piezo for maintaining male copulation posture. piezo-GAL4-positive signals were found in the sensory neurons of male genitalia bristles, and optogenetic inhibition of piezo-expressing neurons in the posterior side of the male body during copulation destabilized posture and terminated copulation. Our findings suggest that the mechanosensory system of male genitalia through Piezo channels plays a key role in copulation maintenance and indicate that Piezo may increase male fitness during copulation in flies.

Summary: Huddling behavior, a typical social interaction among animals, has the benefits of obtaining social support and adapting environment. Huddling behavior is determined by social (social hierarchy), environmental factors (stress events), and the neuroendocrine system. Nevertheless, the huddling behavior of different social hierarchies and the underlying mechanisms have not been fully elucidated. In the present study, acute 2-methyl-2-thiazoline (2 MT) can induce huddling behavior and significantly increase serum levels of testosterone (T) in mice; and the increased T level was positively correlated with huddling behavior. Further, the T treatment significantly increased the huddling behavior in mice under 2 MT exposure condition. More interestingly, T can quickly promote dominant individuals to occupy safe positions when huddling together under predator odor. Collectively, T can rapidly regulate the individual’s adaptive response to threats in a social rank-dependent manner, which provides a new perspective for the in-depth study of the influencing factors and underlying mechanisms of huddling behavior.

Summary: Sea urchins can detect light and move in relation to luminous stimuli despite lacking eyes. They presumably detect light through photoreceptor cells distributed on their body surface. However, there is currently no mechanistic explanation of how these animals can process light to detect visual stimuli and produce oriented movement. Here, we present a model of decentralized vision in echinoderms that includes all known processing stages, from photoreceptor cells to radial nerve neurons to neurons contained in the oral nerve ring encircling the mouth of the animals. In the model, light stimuli captured by photoreceptor cells produce neural activity in the radial nerve neurons. In turn, neural activity in the radial nerves is integrated in the oral nerve ring to produce a profile of neural activity reaching spatially across several ambulacra. This neural activity is readout to produce a model of movement. The model captures previously published data on the behavior of sea urchin Diadema africanum probed with a variety of physical stimuli. The specific pattern of neural connections used in the model makes testable predictions on the properties of single neurons and aggregate neural behavior in Diadema africanum and other echinoderms, offering a potential understanding of the mechanism of visual orientation in these animals.

Summary: A spatiotemporal pattern of excitability propagates across the primary motor cortex prior to the onset of a reaching movement in non-human primates. If this pattern is a necessary component of voluntary movement initiation, it should be present across a variety of motor tasks, end-effectors, and even species. Here, we show that propagating patterns of excitability occur during the initiation of precision grip force and tongue protrusion in non-human primates, and even isometric wrist extension in a human participant. In all tasks, the directions of propagation across the cortical sheet were bimodally distributed across trials with modes oriented roughly opposite to one another. Propagation speed was unimodally distributed with similar mean speeds across tasks and species. Additionally, propagation direction and speed did not vary systematically with any behavioral measures except response times indicating that this propagating pattern is invariant to kinematic or kinetic details and may be a generic movement initiation signal.

Summary: Olfactory stimuli from food influence energy balance, preparing the body for digestion when food is consumed. Social chemosensory cues predict subsequent energetic changes required for social interactions and could be an additional sensory input influencing energy balance. We show that exposure to female chemostimuli increases metabolic rate in male mice and reduces body weight and adipose tissue expansion when mice are fed a high-fat diet. These responses are linked to detection of female chemostimuli via G-protein Gαo-expressing vomeronasal sensory neurons. Males with Gαo deleted in the olfactory system are fertile but do not show changes in body weight when paired with females and show severely blunted changes in energy expenditure when exposed to female bedding. These results establish that metabolic and reproductive responses to females can be partly uncoupled in male mice and that detection of female chemostimuli is a central regulator of energy metabolism and lipid storage.

Summary: Locust swarms can extend over hundred kilometers, and starvation compels this ancient pest to devour everything in its path. Theory suggests that gregarious behavior benefits foraging efficiency, yet the role of social cohesion remains elusive. To this end, we collected high-resolution trajectories of individual and grouped gregarious desert locusts in a 2-choice assay with patches of either similar or different quality. Carefully maintaining animals’ identities allowed us to monitor each individual’s experience and estimate the leaky accumulation process of personally acquired and socially derived evidence. We fitted data to a Bayesian model to gain insight into the decision-making system for patch selection. By disentangling the relative contribution of each information class, our study suggests that locusts balance incongruent evidence but reinforce congruent ones. We provide insight into the collective foraging decisions of social (but non-eusocial) insects and present locusts as a powerful empirical system to study individual choices and consequent collective dynamics.

Summary: The mechanism by which acute pain or itch information at the periphery is processed in the primary somatosensory cortex (S1) remains unclear. To elucidate this, we used a viral-mediated targeted-recombination-in-active population system to target S1 neuronal ensembles that are active during pain or itch sensations. We induced the expression of excitatory or inhibitory designer receptors exclusively activated by designer drugs in pain- or itch-related S1 neurons. We identified neuronal populations in mice that regulate the sensory components of pain and itch in the S1 hind paw region. Notably, the neuronal circuit between pain-related S1 neurons and the parafascicular nucleus contributed to hyperalgesia and anxiety-like behavior. We propose that S1 plays an essential role in sensory and affective responses to noxious stimuli, such as pain.

Summary: Successfully navigating dynamic environments requires organisms to learn the consequences of their actions. The prelimbic prefrontal cortex (PL) formulates action-consequence memories and is modulated by addictive drugs like cocaine. We trained mice to obtain food rewards and then unexpectedly withheld reinforcement, triggering new action-consequence memory. New memory was disrupted by cocaine when delivered immediately following non-reinforcement, but not when delayed, suggesting that cocaine disrupted memory consolidation. Cocaine also rapidly inactivated cofilin, a primary regulator of the neuronal actin cytoskeleton. This observation led to the discovery that cocaine also within the time of memory consolidation elevated dendritic spine elimination and blunted spine formation rates on excitatory PL neurons, culminating in thin-type spine attrition. Training drug-naive mice to utilize inflexible response strategies also eliminated thin-type dendritic spines. Thus, cocaine may disrupt action-consequence memory, at least in part, by recapitulating neurobiological sequalae occurring in the formation of inflexible habits.

Summary: People with misophonia have strong aversive reactions to specific “trigger” sounds. Here we challenge this key idea of specificity. Machine learning was used to identify a misophonic profile from a multivariate sound-response pattern. Misophonia could be classified from most sounds (traditional triggers and non-triggers) and, moreover, cross-classification showed that the profile was largely transferable across sounds (rather than idiosyncratic for each sound). By splitting our participants in other ways, we were able to show—using the same approach—a differential diagnostic profile factoring in potential co-morbidities (autism, hyperacusis, ASMR). The broad autism phenotype was classified via aversions to repetitive sounds rather than the eating sounds most easily classified in misophonia. Within misophonia, the presence of hyperacusis and sound-induced pain had widespread effects across all sounds. Overall, we show that misophonia is characterized by a distinctive reaction to most sounds that ultimately becomes most noticeable for a sub-set of those sounds.

Helping behavior are actions aiming at assisting another individual in need or to relieve their distress. The occurrence of this behavior not only depends on automated physiological mechanisms, such as imitation or emotional contagion, that is, the individual's emotion and physiological state matching with others, but also needs motivation to sustain. From a comparative and developmental perspective, we discover that the motivation for helping behavior has a deep foundation both phylogenetically and ontogenetically. For example, empathic concern for others, relieving personal distress and the desire for social contact are universal motivations across rodents, non-human primates and human early childhoods. Therefore, a circle-layered model integrating evidences for motivation for helping behavior from rodent to human early childhood research is proposed: the inner circle contains the emotional-behavioral system and the outer circle contains the affective-cognitive system. The application of this model has significance for both behavioral neuroscience research and cultivating prosocial behavior in human society. [ABSTRACT FROM AUTHOR]

Background: Understanding neural connections facilitates the neuroscience and cognitive behavioral research. There are many nerve fiber intersections in the brain that need to be observed, and the size is between 30 and 50 nanometers. Improving image resolution has become an important issue for mapping the neural connections non-invasively. Generalized q-sampling imaging (GQI) was used to reveal the fiber geometry of straight and crossing. In this work, we attempted to achieve super-resolution with a deep learning method on diffusion weighted imaging (DWI). Materials and methods: A three-dimensional super-resolution convolutional neural network (3D SRCNN) was utilized to achieve super-resolution on DWI. Then, generalized fractional anisotropy (GFA), normalized quantitative anisotropy (NQA), and the isotropic value of the orientation distribution function (ISO) mapping were reconstructed using GQI with super-resolution DWI. We also reconstructed the orientation distribution function (ODF) of brain fibers using GQI. Results: With the proposed super-resolution method, the reconstructed DWI was closer to the target image than the interpolation method. The peak signal-to-noise ratio (PSNR) and structural similarity index measure (SSIM) were also significantly improved. The diffusion index mapping reconstructed by GQI also had higher performance. The ventricles and white matter regions were much clearer. Conclusion: This super-resolution method can assist in postprocessing low-resolution images. With SRCNN, high-resolution images can be effectively and accurately generated. The method can clearly reconstruct the intersection structure in the brain connectome and has the potential to accurately describe the fiber geometry on a subvoxel scale. [ABSTRACT FROM AUTHOR]

A challenge in both modern and historic neuroscience has been achieving an understanding of neuron circuits, and determining the computational and organizational principles that underlie these circuits. Deeper understanding of the organization of brain circuits and cell types, including in the hippocampus, is required for advances in behavioral and cognitive neuroscience, as well as for understanding principles governing brain development and evolution. In this manuscript, we pioneer a new method to analyze the spatial clustering of active neurons in the hippocampus. We use calcium imaging and a rewarded navigation task to record from 100 s of place cells in the CA1 of freely moving rats. We then use statistical techniques developed for and in widespread use in geographic mapping studies, global Moran's I, and local Moran's I to demonstrate that cells that code for similar spatial locations tend to form small spatial clusters. We present evidence that this clustering is not the result of artifacts from calcium imaging, and show that these clusters are primarily formed by cells that have place fields around previously rewarded locations. We go on to show that, although cells with similar place fields tend to form clusters, there is no obvious topographic mapping of environmental location onto the hippocampus, such as seen in the visual cortex. Insights into hippocampal organization, as in this study, can elucidate mechanisms underlying motivational behaviors, spatial navigation, and memory formation. [ABSTRACT FROM AUTHOR]

A series of behavioral detection paradigms have been developed for zebrafish (Danio rerio) to examine anxiety-like behavioral responses. Among them, the novel tank diving test is rapidly gaining popularity in translational neuroscience and behavioral research for the investigation of psychopharmacological activity focusing on stress. Zebrafish respond to conspecific epidermal-released alarm substances with antipredator reactions. Although the alarm responses of zebrafish were well characterized in a novel tank diving experiment, the relationship between the intensity of the alarm behavior and the concentration of the alarm substance needed to be understood more adequately. In the current paper, we investigated the behavioral phenotypes and potencies of zebrafish elicited by the serial dilution of an alarm substance in the novel tank diving test. Using a video-tracking assisted behavioral quantification approach, we demonstrated no linear concentration-dependent relationship between antipredator behavior and skin extracts, suggesting that an optimal concentration induced each typical behavioral response. The results showed that the freezing duration (%) significantly increased when stimulated with 104-fold times dilutions of skin extract (equivalent 5 × 10−5 fish/L), while erratic movements (%), time in the bottom half (%), and latency to the upper half (s) significantly elevated when stimulated with 103-fold times dilutions (equivalent 5 × 10−4 fish/L). Therefore, the concentration threshold for an alarm substance that elicited innate fear behavior in zebrafish was presumed to be an equivalent concentration of approximately 5 × 10−4 fish/L. The conclusions may fill a knowledge gap between the innate fear response triggered by injured skin and a novel tank diving paradigm that provides insights into the characterization of alarm substance, behavioral responses, and physiological response mechanisms in zebrafish. [ABSTRACT FROM AUTHOR]

Studies across a broad range of disciplines—from psychiatry to cognitive science to behavioural neuroscience—have reported on whether the magnitude of contrast sensitivity alterations in one group or condition varies with spatial frequency. Significant interactions have often gone unexplained or have been used to argue for impairments in specific processing streams. Here, we show that interactions with spatial frequency may need to be re‐evaluated if the inherent skew/heteroscedasticity was not taken into account or if visual acuity could plausibly differ across groups or conditions. By re‐analysing a publicly available data set, we show that—when using raw contrast sensitivity data—schizophrenia patients exhibit an apparent contrast sensitivity impairment that lessens with spatial frequency, but that when using log‐transformed data or when using generalized estimating equations, this interaction reversed. The reversed interaction, but not the overall contrast sensitivity deficit, disappeared when groups were matched on visual acuity. An analysis of the contrast threshold data yielded similar results. A caveat is that matching groups on acuity is probably only defensible if acuity differences arise from non‐neural factors such as optical blur. Taken together, these analyses reconcile seemingly discrepant findings in the literature and demonstrate that reporting contrast sensitivity interactions with spatial frequency requires properly accounting for visual acuity and skew/heteroscedasticity. [ABSTRACT FROM AUTHOR]