Autonomous Overtaking for Intelligent Vehicles Considering Social Preference Based on Hierarchical Reinforcement Learning

As intelligent vehicles usually have complex overtaking process,a safe and efficient automated overtaking system(AOS)is vital to avoid accidents caused by wrong operation of drivers.Existing AOSs rarely consider longitudinal reactions of the overtaken vehicle(OV)during overtaking.This paper proposed a novel AOS based on hierarchical reinforcement learning,where the longitudinal reaction is given by a data-driven social preference estimation.This AOS incorporates two modules that can function in different overtaking phases.The first module based on semi-Markov decision process and motion primitives is built for motion planning and control.The second module based on Markov decision process is designed to enable vehicles to make proper decisions according to the social preference of OV.Based on realistic overtaking data,the proposed AOS and its modules are verified experimentally.The results of the tests show that the proposed AOS can realize safe and effective overtaking in scenes built by realistic data,and has the ability to flexibly adjust lateral driving behavior and lane changing position when the OVs have different social preferences.

Estrogen and oxytocin involvement in social preference in male mice:a study using a novel long-term social preference paradigm with aromatase,estrogen receptor-αand estrogen receptor-β,oxytocin,and oxytocin receptor knockout male mice

Certain aspects of social behavior help animals make adaptive decisions during encounters with other animals.When mice choose to approach another conspecific,the motivation and preference behind the interaction is not well understood.Estrogen and oxytocin are known to influence a wide array of social behaviors,including social motivation and social preference.The present study investigated the effects of estrogen and oxytocin on social preference using aromatase(ArKO),estrogen receptor(ER)α(αERKO),ERβ(βERKO),oxytocin(OTKO),oxytocin receptor(OTRKO)knockout and their respective wild-type(WT)male mice.Mice were presented with gonadally-intact versus castrated male(IC),intact male versus ovariectomized female(IF),or intact male versus empty cage(IE)stimuli sets for 5 days.ArWT showed no preference for either stimuli in IC and IF and intact male preference in IE,but ArKO mice preferred a castrated male or an ovariectomized female,or had no preference for either stimulus in IC,IF and IE stimuli sets,respectively,suggesting reduced intact male preference.αandβWT mice preferred a castrated male,showed no preference,and preferred an intact male in IC,IF and IE,respectively.αERKO mice displayed similar modified social preference patterns as ArKO,whereas the social preference ofβERKO mice remained similar toβWT.OTWT preferred a castrated male whereas OTKO,OTRWT and OTRKO mice failed to show any preference in IC and none showed preference for either stimuli in IF.Collectively,these findings suggest that estrogen regulates social preference in male mice and that impaired social preference in oxytocin-deficient mice may be due to severe deficits in social recognition.

How do lateral septum projections to the ventral CA1 influence sociability?

Social dysfunction is a risk factor for several neuropsychiatric illnesses.Previous studies have shown that the lateral septum(LS)-related pathway plays a critical role in mediating social behaviors.Howeve r,the role of the connections between the LS and its downstream brain regions in social behavio rs remains unclea r.In this study,we conducted a three-chamber test using electrophysiological and chemogenetic approaches in mice to determine how LS projections to ventral CA1(vCA1)influence sociability.Our res ults showed that gamma-aminobutyric acid(GABA)-e rgic neuro ns were activated following social experience,and that social behavio rs were enhanced by chemogenetic modulation of these neurons.Moreover,LS GABAergic neurons extended their functional neural connections via vCA1 glutamatergic pyramidal neurons,and regulating LSGABA→vCA1Gluneural projections affected social behaviors,which were impeded by suppressing LSprojecting vCA1 neuronal activity or inhibiting GABAAreceptors in vCA1.These findings support the hypothesis that LS inputs to the vCA1 can control social prefe rences and social novelty behaviors.These findings provide new insights rega rding the neural circuits that regulate sociability.

Avoidance of potentially harmful food cannot be socially transmitted between rats

The social transmission of food preferences （STFP） is a behavioural task of olfactory memory, in which an observer rat learns safe food odours from a demonstrator rat, and shows preference for this odour in a subsequent choice test. However, previous studies have failed to detect the transmission of information about food study, we tested how demonstrators＇ health affects the exchange of of potential danger and food aversion using STFP test. In this odour information and whether observers can learn danger information from an unhealthy demonstrator. As expected, the observer rat formed an odour preference after interacting with a demonstrator rat that had just eaten food containing a new odour, however, odour preference rather than aversion was also formed after interacting with a demonstrator rat injected with LiC1 （used to induce gastric malaise）. Furthermore, anaesthetized demonstrator rats and half-anaesthetized demonstrator rats, which showed obvious motor deficits suggesting an unhealthy state, also socially transmitted food preferences to observers. These results suggest that the social transmission of food preferences task is independent of a demonstrators＇ health, and that information about dangerous foods cannot be transmitted using this behavioural task.

Female mice exhibit both sexual and social partner preferences for vocalizing males

Acoustic signals are widely used as courtship signals in the animal kingdom.It has long been known that male mice emit ultrasonic vocalizations(USVs)in the presence of female mice or in response to female secretions.This observation led to the hypothesis that male USVs play a role in courtship behavior.Although previous studies showed that female mice have a social partner preference for vocalizing males,it is not known if they exhibit a sexual partner preference when given a choice.To address this issue,we examined the copulatory behaviors of female mice with either devocalized males(with or without the playback of the USVs)or sham-operated males in 2 different behavioral paradigms:the no-choice paradigm in the home cage of a male mouse(without choice of mating partners)or the mate-choice paradigm in a 3-chambered apparatus(with choice of mating partners).In the no-choice paradigm,female mice exhibited comparable sexual receptivity with sham-operated and devocalized males.In addition,we found that female mice showed more approach behavior to-wards devocalized males when male USVs were played back.In the mate-choice paradigm,female mice visited more frequently and stayed longer with sham-operated than devocalized males.Furthermore,we showed that female mice received more intromissions from sham-operated males than devocalized males.In summary,our results suggested that,although female mice can copulate equally with both devocalized and vocalizing males when given no choice of mating partner,female mice exhibit both sexual and social partner preferences for vocalizing males in the mate-choice paradigm.