section_path: Definitions
section_name: Definitions
paragraph_text: Definitions
  
  " Addiction " and " addictive behaviour " are polysemes denoting a category of mental disorders, of neuropsychological symptoms, or of merely maladaptive /harmful habits and lifestyles. A common use of "addiction" in medicine is for neuropsychological symptoms denoting pervasive/excessive and intense urges to engage in a category of behavioral compulsions or impulses towards sensory rewards (e.g. alcohol, betel quid, drugs, sex, gambling, video gaming). Addictive disorders or addiction disorders are mental disorders involving high intensities of addictions (as neuropsychological symptoms) that induce functional disabilities (i.e. limit subjects' social/family and occupational activities); the two categories of such disorders are substance-use addictions and behavioral addictions.
  
  Volkow et al. (2016) report that the DSM-5 defines addictions as the most severe degree of the addictive disorders, due to pervasive/excessive substance-use or behavioural compulsions/impulses. It is a definition that many scientific papers and reports use.
  
  " Dependence " is also a polyseme denoting either neuropsychological symptoms or mental disorders. In the DSM-5, dependences differ from addictions and can even normally happen without addictions; besides, substance-use dependences are severe stages of substance-use addictions (i.e. mental disorders) involving withdrawal issues. In the ICD-11, "substance-use dependence" is a synonym of "substance-use addiction" (i.e. neuropsychological symptoms) that can but do not necessarily involve withdrawal issues.