Transformations of neural representations in a social behaviour network

Abstract

Mating and aggression are innate social behaviors that are controlled by subcortical circuits in the extended amygdala and hypothalamus [1][2][3][4] . The bed nucleus of the stria terminalis (BNSTpr) is a node that receives input encoding sex-specific olfactory cues from the medial amygdala (MeApd) 5,6 , and which in turn projects to hypothalamic nuclei that control mating 7-9 (MPOA) and aggression 9-14 (VMHvl), respectively 15 . Previous studies have demonstrated that male aromatase + BNSTpr (AB) neurons are required for mounting and attack, and may identify conspecific sex according to their overall level of activity 16 . However neural representations in BNSTpr, their function and their transformations in the hypothalamus have not been characterized. Here we have performed calcium imaging 17,18 of male BNSTpr Esr1 neurons during social behaviors. We identify distinct populations of female-vs. male-tuned neurons in BNSTpr, with the former outnumbering the latter by ~2:1, similar to MeApd and MPOA but opposite to VMHvl, where male-tuned neurons predominate 6,9,19 . Chemogenetic silencing of BNSTpr Esr1 neurons whilst imaging MPOA Esr1 or VMHvl Esr1 neurons in behaving animals revealed, unexpectedly, that the male-dominant sex-tuning bias in VMHvl was inverted to female-dominant, while a switch from sniff-to mount-selective neurons during mating was attenuated in MPOA. Our data also indicate that BNSTpr Esr1 neurons are not essential for conspecific sex identification. Rather, they control the transition from appetitive to consummatory phases of male social behaviors by shaping sexand behavior-specific neural representations in the hypothalamus.

Hyperexcited limbic neurons represent sexual satiety and reduce mating motivation

“…Consistently, chemogenetic activation of BNST Esr2 strongly suppressed sexual behavior in male mice (fig. S13, A to C), which is contrary to the effect of activating BNST Arom ( 13 ), Esr1 -expressing neurons in the BNSTpr (BNST Esr1 ) ( 18 ), or nearby nonoverlapping BNST St18 (fig. S13, E to G).…”

Independent inhibitory control mechanisms for aggressive motivation and action

“…(However, activity is very modestly increased in the MPO-VMHvl population timed to the female’s entrance.) However, since the VMHvl receives inhibitory input from a variety of other regions known to contain sex-biased coding 5,32 , these other regions may perform other specific types of context gating to prevent attack in the presence of a female.…”

Spatio-temporal patterns of non-autonomous systems on hypergraphs: Turing and Benjamin–Feir mechanisms

“…The assumptions on function G ensure that the uniform equilibrium u * governed by du i /dt = F(u i , t) also satisfies equation (2). Here, the equilibrium can be either fixed points or limit cycles.…”

“…, 1). Therefore, we can study its instability mechanisms to illustrate the formation of spatial patterns of system (2). Standard analysis relies on examining the real parts of the eigenvalues to see if there exist some spatial modes leading to the growing perturbations.…”

“…Over the years, network science has established as a backbone to investigate complex dynamical systems in diverse areas including physics [1], sociology [2], biology [3], the neurosciences [4] and the climate sciences [5]. The natural and artificial systems can be described in terms of networks, with nodes and links representing individual elements and interactions between elements respectively.…”