PROJECT SUMMARY The goal of this project is to provide the building blocks for an independent research program focused on the neural basis of reward-based memory across distributed brain networks. Humans and other animals experience events in the moments they occur while the brain has evolved powerful neural processes to re-activate the neurons encoding these events in the ‘time in-between’.
PROJECT SUMMARY Sensory representations are influenced by an animal’s external context, internal state, past experiences, expectations, and future goals. Prior information – including the history of recent stimuli, actions and rewards – plays an important role in guiding ongoing behavior, and can modulate the neural code even at the level of primary sensory cortex. The involvement of sensory cortex in mediating history- dependent shifts in behavior, and the contributions of specific cell types to these effects are not well understood.
PROJECT SUMMARY To guide decisions, visual information must flow from primary visual cortex (V1) to prefrontal cortex (PFC), via multiple, parallel cortico-cortical and cortico-thalamo-cortical connections. Both V1 and PFC have direct connections with the pulvinar, a higher-order nucleus of the thalamus, but the role of this nucleus in sensory processing is still largely mysterious. Importantly, much of the pulvinar has no homologue in rodents or carnivores, which makes studying it in nonhuman primates all the more important.
PROJECT SUMMARY As we get older, we learn to modulate our behaviors to optimize reward outcomes. These adaptive choices are orchestrated by current sensory conditions, internal cognitive states, and future expectations. In adolescence, rewards circuits that link peripheral detection of sensory stimuli to central circuits involved in decision-making and motivational states continue to grow, remodeling the microcircuit connectivity within the medial prefrontal cortex (mPFC).
Project Summary Social interactions are critical to the physical and emotional health of a wide variety of species. Perturbations in social functioning, a hallmark symptom of many psychiatric and neurodevelopmental disorders such as autism and schizophrenia, can profoundly impair an individual’s ability to sustain healthy social relations. While a growing body of literature has elucidated neural circuits for dyadic social interactions (interactions between two individuals), our understanding of higher order interactions at the level of larger groups is remarkably weak.
PROJECT SUMMARY/ABSTRACT Parental care is essential for offspring well-being and survival yet requires a significant invest from adults without immediate benefit, suggesting the existence of hard-wired mechanisms governing its control. Despite the importance of this evolutionarily controlled behavior, parental behaviors vary greatly between animals of different sex, physiological state, and genetic background.
PROJECT SUMMARY/ABSTRACT Humans have highly advanced cognitive abilities and motor skills, characteristics which are reflected in the enlarged size and cell diversity of our central nervous system (CNS). My overall goal is to profile and compare progenitor cell diversity in humans, non-human primates and rodents, and thereby identify the origins of increased cell diversity and size of the human CNS.
PROJECT SUMMARY The world around us has a statistical structure that we can use to improve our choices. Learning the underlying structure by identifying key features, such as the rate of change, is useful for adapting and optimizing our decision-making strategies. However, learning these features requires accumulating evidence across multiple timescales: a short timescale that considers explicit evidence for the current decision, and a long timescale that supports latent environmental feature inference.
PROJECT SUMMARY / ABSTRACT. Research Project: Spatial memory – memory of where an event happened or an object was located – depends on the hippocampus in a wide range of vertebrate species, including mammals and birds. In humans, most spatial memories are formed through visual experience. However, it is unclear how visual information is processed by hippocampal memory circuits to support spatial memory formation.
This proposal describes a five-year career development program to prepare the candidate, Dr. Nan Xu, for a career as independent investigator at a major academic research institute, with the expertise of modeling dynamics of brain causal system to provide novel insights into the basic pathophysiology of neurologic disorders. This proposal develops upon Dr.
