Inclusion Criteria:  Service users in structured treatment for drug and/or alcohol misuse, Aged 18-65 Reporting / Self-reporting symptoms of depression and/or anxiety. Service users will need to be deemed suitable to take part in a group / individual setting by their key workers. Right-handedness  Exclusion Criteria:  Service users on medication for depression or anxiety, Services users who are currently receiving treatment as part of a Drug Rehabilitation Requirement (DRR) or Alcohol Treatment Requirement (ATR). Service users who are unable to provide informed consent due to a lack of mental capacity, Service users with little/no understanding of spoken English. Service users with a brain injury or history of epilepsy. Left-Handedness Mixed-Handedness Not registered with a General Practitioner (GP) / unable to provide GP details