Training

Project Summary Uncertainty is an often pervasive, stressful experience that arises when making judgments about others' beliefs, intentions, or emotions (i.e., ambiguous social situations). Excessive uncertainty can have pernicious effects upon memory, mood, and physical and mental outcomes. Yet, we understand little of how judgments of social certainty form over time, the neural circuitry underlying these judgments, and how these judgments meaningfully differ from non-social uncertainty sources (e.g., calculations, perceptions).

Hypothalamic tanycytes have limited postnatal neurogenic competence, but the extrinsic and intrinsic factors that promote this are not well understood. My predoctoral research identified a defined developmental window during which neurogenic competence is lost from hypothalamic tanycytes. I have also identified the neurogenic bHLH transcription factor Ascl1 as a candidate activator of neurogenic competence in tanycytes and identified Shh signaling as potentially promoting the survival of tanycyte-derived neurons.

PROJECT SUMMARY Poor sleep is common in neurodevelopment disorders such as autism spectrum disorder (ASD), with up to 93% of ASD individuals reporting sleep problems. These problems worsen quality of life and core symptoms of ASD and likely precede an ASD diagnosis, suggesting they start early in life. The potential adverse impact of early life sleep disruption is supported by animal model studies showing long term functional consequences on behavior. However, little is known about the underlying molecular consequences of sleep deprivation (SD) early in life.

Project Summary Visual attention differences are a promising diagnostic marker for autism spectrum conditions (ASC). Yet, despite mounting evidence for group-level differences in visual attention, particularly for visual attention directed toward socially relevant information (i.e., “social gaze”) between autistic and non-autistic individuals, the source of gaze differences in autism remains unclear. Prominent theories of social gaze differences focus heavily on a particular category of visual stimuli, namely: faces.

PROJECT SUMMARY/ABSTRACT After a stroke, walking ability can be compromised, which can lead to reduced quality of life and decreased ability to perform activities of daily living. Post-stroke walking recovery is mediated by nervous system reorganization (e.g., neuroplasticity), however our understanding of these processes related to improvements in walking function are limited due to the neurophysiological complexity of walking itself. Additionally, current practices of assessing stroke- impacted neuroplasticity are heavily focused on the motor system.

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.