Biology subjects

O'Donnell, B. F.

Publications and source records attributed to O'Donnell, B. F..

2 recordsLinked to original sources

bioRxiv2019

Long-Term Aberrations To Cerebellar Endocannabinoids Induced By Early-Life Stress

Studies of early-life stress traditionally focus on glucocorticoid signaling as a modulator of neurodevelopmental risk, but emerging evidence points to the role of the endocannabinoid system in long-term stress-induced neural remodeling. Existing studies on stress-induced endocannabinoid dysregulation have focused on changes to cerebrum that are temporally proximal to stressors, but little is known about temporally distal effects, especially in cerebellum, which is vulnerable to early developmental stress and is dense with cannabinoid receptors. Further, sex-specific effects of stress on cerebellar endocannabinoid tone are understudied. Following a naturalistic rodent model of early-life stress, limited bedding at postnatal days 2-9, adult (postnatal day 70) cerebellar and hippocampal endocannabinoids and related lipids and mRNA were assessed, and behavioral performance was evaluated. Regional and sex-specific effects were present at baseline and following early-life stress. Limited bedding impaired peripherally-measured basal corticosterone in adult males only. In the CNS, early-life stress (1) decreased 2-arachidonoyl glycerol and arachidonic acid in the cerebellar deep nuclei in males only; (2) decreased 2-arachidonoyl glycerol in females only in cerebellar Crus I; and (3) increased dorsal hippocampus prostaglandins in males only. Transcriptomics for cerebellar interpositus nucleus revealed substantial sex effects, with minimal effects of stress. Stress did impair novel object recognition in both sexes and social preference in females. Taken together, the cerebellar endocannabinoids system exhibits robust sex-specific differences, malleable through early-life stress and perhaps also contributing to sexual differentiation of the brain. The current study may foster future research into stress as a risk factor for cerebellar-related dysfunctions.

neuroscience↗

bioRxiv2019

Regret Induces Rapid Learning from Experience-based Decisions: A Model-based Facial Expression Analysis Approach

Whether we are making life-or-death decisions or thinking about the best way to phrase an email, counterfactual emotions including regret and disappointment play an ever-present role in how we make decisions. Functional theories of counterfactual thinking suggest that the experience and future expectation of counterfactual emotions should promote goal-oriented behavioral change. Although many studies find empirical support for such functional theories, the generative cognitive mechanisms through which counterfactual thinking facilitates changes in behavior are underexplored. Here, we develop generative models of risky decision-making that extend regret and disappointment theory to experience-based tasks, which we use to examine how people incorporate counterfactual information into their decisions across time. Further, we use computer-vision to detect positive and negative affect (valence) intensity from participants faces in response to feedback, which we use to explore how experienced emotion may correspond to cognitive mechanisms of learning, outcome valuation, or exploration/exploitation--any of which could result in functional changes in behavior. Using hierarchical Bayesian modeling and Bayesian model comparison methods, we found that a model assuming: (1) people learn to explicitly represent and subjectively weight counterfactual outcomes with increasing experience, and (2) people update their counterfactual expectations more rapidly as they experience increasingly intense negative affect best characterized empirical data. Our findings support functional accounts of regret and disappointment and demonstrate the potential for generative modeling and model-based facial expression analysis to enhance our understanding of cognition-emotion interactions.

neuroscience↗