Kiara R. Timpano, Ph.D. - US grants

ABSTRACT Pathological hoarding behaviors represent a massive public health burden. Approximately 3-5% of the population is estimated to have hoarding disorder, which is characterized by difficulties discarding, severe clutter, and excessive acquiring. These symptoms can range on a spectrum from normative and benign collecting, to extremely debilitating symptoms that rival the impairment noted in other severe and persistently ill psychiatric populations (e.g., schizophrenia). The course of hoarding is chronic and, if left untreated, symptoms can have serious and even life threatening ramifications for the patient and their larger community. Despite remarkable advances in understanding the phenomenology of hoarding, vulnerability or maintaining factors are still poorly understood, and hoarding is also considered difficult to treat, with only modest treatment gains noted for existing interventions. Gaining better insight into the phenomenology of hoarding is critical to identifying effective treatment targets. Decision making deficits have been widely proposed as a central psychopathological feature of hoarding based on clinical reports and preliminary neuroimaging data. A definitive gap in the extant research is that neuropsychological studies of decision making in hoarding have produced strikingly mixed results. We suggest that a potential explanation for these varied results is that decision-making impairments in HD may largely be specific to emotion-based decision making, and these studies have failed to account for the influence of emotional processes on decision paradigms. The primary aim of this study is to examine the role of emotion-based decision making in individuals who hoard. We seek to characterize these impairments by examining decision-making impairments across two measures derived within behavioral neuroeconomics, including one task that will examine value-based decision making under highly relevant domains of risk and ambiguity, as well as one task that captures multi-attribute decision making. In both tasks, an emotionally neutral condition will be compared to a stressful condition, allowing us to examine the emotion-cognition interaction in hoarding. To examine whether decision-making impairments are specific to those who hoard, a hoarding sample will be compared with age-matched individuals with anxious distress and healthy controls. Our secondary aims are to explore potential mechanisms of these decision making impairments, examining candidate moderators including peripheral physiologic response and subjective distress tolerance. The approach is innovative, because it represents an integration of psychology, neuroscience, and behavioral economics to create a more nuanced understanding of HD-related deficits. The proposed research is significant because it has the potential to explain a great deal of the overt symptoms of HD and functional impairments, and will directly inform future translational studies of novel treatment approaches (e.g., cognitive remediation, innovative technology) in hoarding and related conditions.

PROJECT ABSTRACT Much attention has been focused on dysfunction associated with high or low approach motivation, or with deficits in effortful control. Recent evidence suggests, however, that it is important to consider these two dimensions jointly. We suggest that high approach motivation is related to externalizing syndromes, low approach motivation is related to internalizing syndromes, and that high effortful control dampens the effects of both of these extremes of approach motivation. We propose to take a multi-level approach to systematically investigate a broad range of internalizing and externalizing syndromes. This project will address two critical gaps: 1) Researchers to date have rarely considered approach motivation and cognitive control jointly. 2) Researchers have not examined how models of approach and effortful control can explain a broad range of both internalizing and externalizing syndromes. To address these gaps, our proposal has three specific aims: Aim 1: Investigate associations between neural, behavioural, and self-report indices of approach motivation. Aim 2: Investigate associations between neural, behavioral, and self-report indices of effortful control. Aim 3: Investigate how the confluence of high approach motivation and low effortful control predict a range of externalizing syndromes in a community outpatient sample. Aim 4: Investigate how the confluence of low approach motivation and low effortful control predict a range of internalizing syndromes in the same sample. Knowledge gained will provide information about core motivational and control deficits in psychopathology and their neural basis, and provide an important base for treatment development. The aims of this project fit NIMH goals of integrating basic research with clinical science to enhance outcomes for those with mental illness.