One possible explanation for CBT"s lack of effect on anxiety symptoms is that due to the nature of their ADHD, individuals with comorbid anxiety may not respond well to certain treatment methods used in CBT. For example, habituation and exposure therapy require the patient to be exposed to a stimulus that causes them anxiety for a certain amount of time without interruption. Therefore, such treatment would not work as well on someone who becomes distracted and struggles to pay attention. As a result, anxiety disorders such as OCD and social phobia may be especially difficult to treat using CBT as exposure therapy is a vital aspect of treatment.