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The cerebral cortex is widely accepted to be involved in the control of cognition and the processing of learned information. However, data suggest that it may also have a role in the regulation of innate responses because rodents, cats or primates with surgical removal of cortical regions show excessive aggression and rage elicited by threatening stimuli. Nevertheless, the imprecision and chronic nature of these lesions leave open the possibility that compensatory processes may underlie some of these phenotypes. In the present study we applied a precise, rapid and reversible inhibition approach to examine the contribution of the cerebral cortex to defensive behaviours elicited by a variety of innately aversive stimuli in laboratory mice. Pharmacological treatment of mice carrying the pharmacogenetic inhibitory receptor hM4D selectively in neocortex, archicortex and related dorsal telencephalon‐derived structures resulted in the rapid inhibition of cerebral cortex neural activity. Cortical inhibition was associated with a selective increase in defensive behaviours elicited by an aggressive conspecific, a novel prey and a physically stressful stimulus. These findings are consistent with a role for cortex in the acute inhibition of innate defensive behaviours. [ABSTRACT FROM AUTHOR]

Prior research has demonstrated the role of kind school climate in students' academic and social-emotional learning outcomes. However, there is sparse literature showing the link of school kindness to mental health functioning. This study examines the association of school kindness with well-being dimensions such as positive emotions and depressive symptoms among 1287 Filipino high school students. It also explored whether school kindness would have indirect effects on well-being via school belongingness. Structural equation modeling via maximum likelihood estimation approach showed that school kindness was linked to higher positive emotions and lower depressive symptoms after controlling for demographic covariates such as age and gender. Further, results of bias-corrected bootstrapping analyses demonstrated that school kindness had indirect effects on positive emotions and depressive symptoms via school belongingness. This research underscores the mental health benefits associated with fostering kindness in school contexts. [ABSTRACT FROM AUTHOR]

In the course of language acquisition learners have to deal with the task of producing narrative texts that are coherent across a range of conceptual domains (space, time, entities) - both within as well as across utterances. The organization of information is analyzed in this study, on the basis of retellings of a silent film, in terms of devices used in the coordination and subordination of events within the narrative sequence. The focus on subordination reflects a core grammatical difference between Italian and French, as Italian is a null-subject language while French is not. The implications of this contrast for information structure include differences in topic management within the sequence of events. The present study investigates in how far Italian-French bilingual speakers acquire the patterns of monolingual speakers of Italian. It compares how early and late bilinguals of these two languages proceed when linking information in narratives in Italian. [ABSTRACT FROM AUTHOR]

A remaining challenge for genetically encoded voltage indicators (GEVIs) is the reliable detection of excitatory postsynaptic potentials (EPSPs). Here, we developed ASAP5 as a GEVI with enhanced activation kinetics and responsivity near resting membrane potentials for improved detection of both spiking and subthreshold activity. ASAP5 reported action potentials (APs) in vivo with higher signal-to-noise ratios than previous GEVIs and successfully detected graded and subthreshold responses to sensory stimuli in single two-photon trials. In cultured rat or human neurons, somatic ASAP5 reported synaptic events propagating centripetally and could detect ∼1-mV EPSPs. By imaging spontaneous EPSPs throughout dendrites, we found that EPSP amplitudes decay exponentially during propagation and that amplitude at the initiation site generally increases with distance from the soma. These results extend the applications of voltage imaging to the quantal response domain, including in human neurons, opening up the possibility of high-throughput, high-content characterization of neuronal dysfunction in disease. [Display omitted] • Multiparametric screening generated a GEVI with higher gain and faster onset, ASAP5 • ASAP5 exhibits higher responsivity to action potentials and mEPSPs than other GEVIs • ASAP5 reveals mEPSP dendritic propagation and network activity in rat and human neurons • ASAP5 demonstrated high-SNR voltage recordings in flies, fish, and mice Hao, Lee, et al. report ASAP5, a GEVI that enhances responsivity and accelerates kinetics. It enables single-trial recordings of sub- and suprathreshold activities in flies, mice, and human stem-cell-derived neurons, offering new possibilities to study the dynamics of membrane potentials from 1 to 100 mV. [ABSTRACT FROM AUTHOR]

Predators must frequently balance competing approach and defensive behaviors elicited by a moving and potentially dangerous prey. Several brain circuits supporting predation have recently been localized. However, the mechanisms by which these circuits balance the conflict between approach and defense responses remain unknown. Laboratory mice initially show alternating approach and defense responses toward cockroaches, a natural prey, but with repeated exposure become avid hunters. Here, we used in vivo neural activity recording and cell-type specific manipulations in huntingmale mice to identify neurons in the lateral hypothalamus and periaqueductal gray that encode and control predatory approach and defense behaviors. We found a subset of GABAergic neurons in lateral hypothalamus that specifically encoded hunting behaviors and whose stimulation triggered predation but not feeding. This population projects to the periaqueductal gray, and stimulation of these projections promoted predation. Neurons in periaqueductal gray encoded both approach and defensive behaviors but only initially when the mouse showed high levels of fear of the prey. Our findings allow us to propose that GABAergic neurons in lateral hypothalamus facilitate predation in part by suppressing defensive responses to prey encoded in the periaqueductal gray. Our results reveal a neural circuit mechanism for controlling the balance between conflicting approach and defensive behaviors elicited by the same stimulus. [ABSTRACT FROM AUTHOR]