PROJECT ABSTRACT Osteoarthritis (OA) is a major and growing public health problem that negatively impacts quality of life. The prevalence of painful arthritis in the U.S. likely approaches ~90 million adults and clinical sequela of OA-associated pain include decreased mobility and compromised activity. Importantly, the chronic pain experience in humans frequently includes profound and debilitating effects on the emotional state, with significant negative impacts on quality of life and function. Consequences also include impaired performance on cognitive tasks, particularly those requiring working memory or attentional switching. These effects compound the clinical picture, contributing to the pain-related depression, anxiety, and emotional distress (the `experience' of chronic pain). Research relying on rodent models is not translating into new, effective treatments. One reason for the lack of translational success is that despite the clear importance of emotion and cognition in the human chronic pain experience, current models of chronic pain in animals frequently ignore these critical domains. The major goal of the proposed studies is to bridge this `model gap' and significantly advance translational research capability by developing and rigorously validating a battery of assays for assessment of emotions and cognitive function in the pet dog model of persistent OA pain. Pet dogs with naturally occurring persistent OA pain are already considered a good model of the sensory- discriminative aspects of OA pain in humans; enhancing the capability of this model will allow researchers, for the first time, to access a clinically relevant full biopsychosocial animal model of persistent pain. We will achieve this through developing, refining and rigorously validating (test-retest, structural, discriminative, responsiveness, and criterion validity) a battery of emotional and cognitive domain tests, benchmarking against validated measures of pain and the impact of pain. Applying advanced statistical techniques, we will create a concise battery that can be feasibly performed in clinical research settings. We bring together diverse expertise with proven track records of collaboration and established facility resources to successfully address this critical gap in modeling the pain experience of humans. Successful completion of this proposed work will validate a highly clinically relevant biopsychosocial animal model of persistent musculoskeletal pain that has the potential to radically increase the translation of pre-clinical knowledge into effective, non-addictive analgesic treatments for humans suffering from persistent musculoskeletal pain.