Insula to mPFC reciprocal connectivity differentially underlies novel taste neophobic response and learning

To survive in an ever-changing environment, animals must detect and learn salient information. The anterior insular cortex (aIC) and medial prefrontal cortex (mPFC) are heavily implicated in salience and novelty processing, and specifically, the processing of taste sensory information. Here, we examined the role of aIC-mPFC reciprocal connectivity in novel taste neophobia and memory formation, in mice. Using pERK and neuronal intrinsic properties as markers for neuronal activation, and retrograde AAV (rAAV) constructs for connectivity, we demonstrate a correlation between aIC-mPFC activity and novel taste experience. Furthermore, by expressing inhibitory chemogenetic receptors in these projections, we show that aIC-to-mPFC activity is necessary for both taste neophobia and its attenuation. However, activity within mPFC-to-aIC projections is essential only for the neophobic reaction but not for the learning process. These results provide an insight into the cortical circuitry needed to detect, react to- and learn salient stimuli, a process critically involved in psychiatric disorders.

Insula to mPFC reciprocal connectivity differentially underlies novel taste neophobic response and learning

To survive in an ever-changing environment, animals must detect and learn salient information. The anterior insular cortex (aIC) and medial prefrontal cortex (mPFC) are heavily implicated in salience and novelty processing, and specifically, the processing of taste sensory information. Here, we examined the role of aIC-mPFC reciprocal connectivity in novel taste neophobia and memory formation, in mice. Using pERK and neuronal intrinsic properties as markers for neuronal activation, and retrograde AAV (rAAV) constructs for connectivity, we demonstrate a correlation between aIC-mPFC activity and novel taste experience. Furthermore, by expressing inhibitory chemogenetic receptors in these projections, we show that aIC-to-mPFC activity is necessary for both taste neophobia and its attenuation. However, activity within mPFC-to-aIC projections is essential only for the neophobic reaction but not for the learning process. These results provide an insight into the cortical circuitry needed to detect, react to- and learn salient stimuli, a process critically involved in psychiatric disorders.

Coyote responses to visual and olfactory stimuli related to familiarity with an area

Individual coyotes (Canis latrans) are infrequently captured within their familiar areas of activity. Current hypotheses are that the differential capture vulnerability may involve neophobia or inattentiveness. To assess the effect of familiarity, I measured coyote responsiveness to sensory cues encountered in familiar and novel settings. Seventy-four captive coyotes were presented with visual and olfactory stimuli in familiar and unfamiliar 1-ha enclosures. The visual stimuli were black or white wooden cubes of three sizes (4, 8, and 16 cm per side). The olfactory stimuli were fatty acid scent, W-U lure (trimethylammonium decanoate plus sulfide additives), and coyote urine and liquefied feces. Overall, coyotes were more responsive to stimuli during exploration in unfamiliar than in familiar enclosures. None of 38 coyotes that responded were neophobic toward the olfactory stimuli. The frequency of coyote response, and the resulting degrees of neophobia, did not differ between the black and white visual stimuli. Regardless of context, the largest visual stimuli were recognized at the greatest distance and evoked the strongest neophobic response. A greater proportion of coyotes were neophobic toward the small and medium-sized stimuli in familiar than in unfamiliar enclosures. This study demonstrated that when encountered in familiar environments, visual cues are more likely to elicit neophobic responses by coyotes than are olfactory stimuli.