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Biology subjects

Amadei, E. A.

Publications and source records attributed to Amadei, E. A..

4 recordsLinked to original sources

Activation of latent programs for maternal behavior

Maternal behaviors in mammals, which are critical for offspring survival, involve complex interactions between innate neural circuits and behavioral flexibility. This flexibility depends on environmental needs and external stimuli. Recent studies suggest that social transmission plays a crucial role in the acquisition of maternal behaviors in alloparental (non-maternal) subjects, particularly highlighting visual observation for virgin female mice to acquire pup retrieval behavior. However, the extent to which these behaviors rely on social transmission versus the activation of pre-existing, latent behaviors remains unclear. Here, we systematically investigated the necessity of social observation for maternal behavior acquisition, using a social transmission pup retrieval paradigm in pup-naive virgin female mice. Following the same protocol as previous studies, we compared retrieval performance on conditions that either allowed or prevented the visual observation of maternal demonstrations. Contrary to previous findings reporting substantial differences between these conditions, we found that virgin females readily acquired pup retrieval behavior regardless of their visual access to experienced mothers. We observed no significant correlation between maternal and virgin performance after task exposure. Detailed behavioral analysis revealed that the primary difference between mothers and virgins lay on the latency to initiate the behavior, but once started, virgins complete the retrieval as fast as mothers. Together, our findings show that pup exposure is enough to activate latent behaviors, and suggest that pup retrieval might not be transmitted by visual observation.

animal behavior and cognition↗

Inhibition from the oxytocin system tunes prefrontal circuit dynamics to promote social behavior

The prefrontal cortex (PFC) plays a central role in the selection and expression of diverse social behaviors. A balance of excitation and inhibition is necessary for normal social functioning, but it remains unclear how inhibition sculpts pyramidal activity to promote specific social behaviors. To address this question, we developed a novel decision-making task in which female mice chose between interaction with a male (sociosexual stimulus) or an appetitive non-social option (milk solution). To explore the role of a task-relevant inhibitory subpopulation, we targeted neurons in the medial PFC (mPFC) expressing oxytocin receptors (OXTR neurons). Combining optogenetic inhibition of OXTR neurons with population calcium imaging of pyramidal neural activity, we found that OXTR neurons normally promote interaction with a male compared to a non-social alternative. OXTR neurons also regulate pyramidal activity, which enables a specific ensemble to represent the male option during decision-making. Computational modeling reproduced these findings through a pyramidal competition mechanism, in which regulation by OXTR neurons allows a male-representing pyramidal ensemble to effectively compete against the remaining pyramidal population to drive male choice. These results provide a candidate mechanism by which inhibition enables mPFC pyramidal activity to select for specific social behaviors and may help explain why excitation/inhibition balance is so important for social functioning.

neuroscience↗

Population-level neural correlates of flexible avoidance learning in medial prefrontal cortex

The medial prefrontal cortex (mPFC) has been proposed to link sensory inputs and behavioral outputs to mediate the execution of learned behaviors. However, how such a link is implemented has remained unclear. To measure prefrontal neural correlates of sensory stimuli and learned behaviors, we performed population calcium imaging during a novel tone-signaled active avoidance paradigm in mice. We developed a novel analysis approach based on dimensionality reduction and decoding that allowed us to identify and isolate population activity patterns related the tone stimulus, learned avoidance actions and general motion. While tone-related activity was not informative about behavior, avoidance-related activity was predictive of upcoming avoidance actions. Moreover, avoidance-related activity distinguished between two different learned avoidance actions, consistent with a model in which mPFC contributes to the selection between different goal-directed actions. Overall, our results suggest that mPFC circuit dynamics transform sensory inputs into specific behavioral outputs through distributed population-level computations.

neuroscience↗

Striatum-projecting prefrontal cortex neurons support working memory maintenance

The medial prefrontal cortex (mPFC) and the dorsomedial striatum (dmStr) are linked to working memory (WM) but how striatum-projecting mPFC neurons contribute to WM encoding, maintenance, or retrieval remains unclear. Here, we probed mPFC[->]dmStr pathway function in freely-moving mice during a T-maze alternation test of spatial WM. Fiber photometry of GCaMP6m-labeled mPFC[->]dmStr projection neurons revealed strongest activity during the delay period that requires WM maintenance. Demonstrating causality, optogenetic inhibition of mPFC[->]dmStr neurons only during the delay period impaired performance. Conversely, enhancing mPFC[->]dmStr pathway activity--via pharmacological suppression of HCN1 or by optogenetic activation during the delay-- alleviated WM impairment induced by NMDA receptor blockade. Consistently, cellular-resolution miniscope imaging resolved preferred activation of >50% mPFC[->]dmStr neurons during WM maintenance. This subpopulation was distinct from neurons showing preference for encoding and retrieval. In all periods, including the delay, neuronal sequences were evident. Striatum-projecting mPFC neurons thus critically contribute to spatial WM maintenance.

neuroscience↗