Being creative means having the ability to produce ideas, actions or works that are original and different from what we have already done. This process involves mental flexibility, in particular the association of distant ideas or divergent thinking. This creative potential is complex and depends on a number of factors, both internal (personality, motivation, emotional state, stress) and external to the individual (socio-cultural context). The generation of creative ideas involves the fronto-striatal circuit, with a balance between flexibility and perseverance. The striatum is central to the reward system and mental flexibility, while the prefrontal cortex is involved in executive control, underpinning perseverance functions. Dopamine plays a key role in this balance, and changes in dopamine levels, depending on the type of receptor activated, will have a direct impact on the transition between mental flexibility and perseverance. Furthermore, in the context of chronic pain, changes in connectivity and activity can be observed in neuroimaging in these same regions of the reward circuit. This suggests that the dopaminergic system is also involved in the chronicisation of pain. The creative process would therefore be correlated with the dopaminergic reward system, involving several dimensions, both cognitive in terms of mental flexibility, coping strategies and perseverance, and motivational. In this context, art therapy treatments are beginning to be studied, particularly in patients suffering from Alzheimer's or Parkinson's disease, showing improvements in anxiety and depression.

Art therapy has not yet been widely proposed or studied for patients suffering from chronic pain. A more detailed behavioural study would confirm and clarify the clinical benefits for patients, by exploring the neuronal circuits involved, particularly the dopaminergic reward system.

Inclusion Criteria:

• Patient aged 18 and over
• Consent to participate in the study
• Available for protocol visits
• Treated for chronic pain

Exclusion Criteria:

• Progressive neurodegenerative neurological pathology impairing cognitive function
• Untreated clinical depressive syndrome
• Fibromyalgia in the foreground
• High doses of opioid treatment (greater than 100 mg/d of morphine equivalent)
• Impaired judgement or inability to receive information that prevents performance of behavioural tasks
• Absolute contraindication to MRI (e.g. pacemaker and implantable stimulator not MRI compatible, intra-orbital metallic foreign body);
• Persons benefiting from a legal protection measure
• Pregnant or breast-feeding women
• Patient deprived of liberty
• Patient suffering from mental disorders

In order to limit biases linked to the absence of blinding and to potential patient preferences for one or other of the interventions, a "consent to postponed information" type of consent (Boter et al. 2003) will be used.