Chronic pain is often associated with altered emotional processing and impaired motivation, and high comorbidities between chronic pain and affective disorders are a well-known phenomenon. Many overlaps in the neural processing of pain, motivation, and emotion have been reported. For example, multiple brain regions that are involved in the processing of pain are also implicated in the processing of affective events or information. Similarly, dysfunction of mesolimbic circuitry, which results in impaired motivated behavior and has been discussed as causal in affective disorders, has been observed in chronic pain. Accordingly, it has been proposed that altered functioning of brain circuits processing affect and saliency contribute to chronic pain. Apart from these neurophysiological overlaps, pain, motivation, and emotion show many similarities and interactions on a psychological level. For example, pain is a form of stress that shifts motivational systems and thus induces the urge for protective behaviors (e.g., escape, avoidance, and control). In addition, emotional experiences, positive as well as negative, can modulate the perception of pain. Based on these observations it is further conceivable that the joint pharmacological and nonpharmacological treatment of both pain and motivational-emotional disturbances could result in fruitful synergies improving not only the treated symptoms but possibly also other often related disturbances such as cognitive impairments.

This special issue aims at creating a multidisciplinary view on the phenomenon of chronic pain and altered emotional-motivational processing. Recent advances from basic to clinical research will be discussed, giving the reader novel insights into the intersection between chronic pain, emotion, and motivation, as well as into the mechanisms of comorbid affective disorders and possible new applications in pain therapy. Authors are invited to contribute original research as well as review articles on this highly important area of research illustrating the ongoing effort to understand these overlaps and comorbidities from the view of different disciplines ranging from molecular and behavioural studies in animal models to neuroimaging and psychological investigations in healthy volunteers and patients.

Potential topics include but are not limited to the following:

• Multidisciplinary characterizations of the intersection of pain and emotional-motivational processing
• Epidemiology of chronic pain and affective/motivational comorbidities (anxiety, depression, and anhedonia in chronic pain patients)
• Insights into the molecular processes underlying chronic pain, emotional and motivational processing, and affective comorbidities including synaptic plasticity and genetic/epigenetic mechanisms
• Recent discoveries on the role of neurotransmitters in chronic pain, emotional and motivational processing, and affective comorbidities
• Brain regions and circuits meditating the overlap of pain, emotion, and motivation
• Identification of psychological mechanisms explaining the overlap of chronic pain, altered emotional-motivational processing, and affective comorbidities
• Gender as a factor modulating motivational-emotional processes in chronic pain
• Models of chronic pain and affective comorbidities—the impact of chronic pain on affective/motivational behavior in animal pain models
• Effects of pharmacological and nonpharmacological treatments of chronic pain on motivational-emotional disturbances