Fighting mirror neurons found in mouse hypothalamus

A recent study published in the journal cellinvestigators utilized a genetically encoded mirror-TRAP strategy to investigate the functional importance of attack mirroring neurons.

Social interaction requires understanding and awareness of the actions of others. Studies have proposed mirror neurons, or cells that exhibit behavior by self and others, as a key component of the cognitive substrate that facilitates understanding and cognition. Primate neocortical mirror neurons have been reported to be involved in skilled motor tasks. However, the importance of neuronal behavior and social interaction is unknown. In a recent study, VMHvl^{public relations} Neurons provoke aggression in socially contextual ways. This shows that the moniker attack center is naive and ignores important properties of neurons.

study: Hypothalamic neurons that reflect aggressionImage credit: Billion Photos / Shutterstock

About research

In this study, researchers investigated whether VMHvl.^{public relations} Neurons can recognize aggressive interactions between mice.

Using a TRAP2-based activity tagging approach, we gained genetic access to neurons that mirror aggression (mirror TRAPs) and investigated their functional relevance in aggressive behavior. VMHvl^{public relations} The neural responses of mice engaged in fighting were evaluated and compared to those of mice that had witnessed the aggression.

GCaMP6s were expressed in VMHvl.^{public relations} neurons in ^{public relations}Cre mice, and fiber photometry were used to image VMHvlPR neuronal activity in mice after introduction of male intruders into the cage. VMHvl^{public relations} Neural activity in individually water-jetted males (demonstrators) that observed but did not display aggressive behavior was also assessed. Aggression mirroring with BNST^Tac1 Neurons were investigated by expressing GCaMP6 on Tac1^Kure Imaging male cells and VMHvl^{public relations} Neuronal interactions between Trpc2^-/- demonstrator mouse.

To investigate the need for visual input during invasion mirroring, a perforated partition arena was illuminated using infrared light to which mouse animals were desensitized. We then replaced the perforated partition with a solid transparent partition to reduce the pheromone access of demonstrator mice to observer mice.Additionally, miniscope calcium imaging was performed to investigate VMHvl^{public relations} Neuronal activity during attack enactment and observation.

The GCaMP6s signal of individual neurons is the VMHvl^{public relations} Neurons showed alternating activation and inhibition during periods of aggression and tail clatter. Simultaneous neuronal activation between aggressor and observer mice during aggressive display was investigated.

VMHvl^{public relations} Neurons whose activity was restricted to the observer or the aggressor during tail calls or aggression were assessed to assess the functional importance of the observer VMHvl.^{public relations} Tug-of-war cells were investigated. A virus-encoded Cre-based inhibitory chemogenetic actuator, DREADDi, was delivered to VMHvl cells and activated neurons were captured among observer TRAP2 male mice, following clozapine-N-oxide (CNO) administration. Males were tested using a resident-invasive territorial combat assay.

result

Individual VMHvl^{public relations} Neurons were activated simultaneously during observation and execution of attack and tail rattle. Visual input was essential for attack mirroring with VMHvl, but not the previous social experience^{public relations} neuron. VMHvl activity^{public relations} Neurons reflect aggression between other individuals. Aggression Mirroring VMHvl^{public relations} Neurons played a specific and important role in displaying male turf wars.

CNO-treated males had enhanced aggression towards mirrors, were three times more likely to tail purr, and 10 times more tail purrs. Male mice did not attack mirrors. This indicates that other sensory or contextual cues are required to provoke aggression. Activation of her VMHvl neurons, which reflect aggressive behavior, enhanced male territorial aggression and replaced male sexual behavior with aggression. Neurons increased aggression towards female, male, and mirror her mice.

Neurons whose activity mirrored fighting by other mice were identified in the hypothalamus of male mice and were functionally important for aggression. Mirror neuron activity has been shown to be important in combat, and forced activation of neurons induced aggressive display by animal animals in mice and was also aggressive to mirror images. Mirror TRAPed VMHvl^{public relations} Aggression-reflecting neurons were essential and appropriate for inducing aggression displays in males. VMHvl activation^{public relations} Neurons were observed during aggressive display and tail rattling.

VMHvl^{public relations} Neurons exhibited mirroring properties to aggression, and such mirroring was not a feature of all populations modulating aggression. Neurons were able to express distinct aggressive motor activity and showed predominantly congruent mirroring. The Aggression Mirror TRAP strategy effectively captured the Aggression Mirroring VMHvl.^{public relations} Can be used for optimal transgene expression in VMHvl.^{public relations} mirror neurons.

Trpc2^-/- VMHvl^{public relations} Neuronal responses during chemical probing experiments were smaller than their wild-type counterparts, indicating that Trpc2 activity is essential for pheromone signaling.Team Observed Activation of Observer VMHvl^{public relations} We detected comparable levels of neuronal cells throughout the perforated partition, with 152 and 88 neurons showing GCaMP6s fluorescence between challenged and observed mice, respectively. Majority of VMHvl (61% to 78%)^{public relations} Cells were activated between the aggressor and the observer during bouts of aggression and tail clatter.

Overall, the findings suggest that the VMHvl^{public relations} Rather than simply constituting an attack center, neurons embody the perception of aggression that can provoke combat in the right context and monitor aggressive third-party interactions. and highlighted the discovery of a non-cortical mirror neuron system in the nucleus of the Cajal, a deeply conserved and evolved hypothalamic region of ancient vertebrates that provides subcortical cognitive substrates critical for social interaction and survival. .