This thesis comprises of three sections including a literature review, research paper, and a critical appraisal. Initially, with the aim of exploring adults’ experiences of receiving a diagnosis of ADHD in adulthood, including capturing life pre- and-post diagnosis, a meta-synthesis was conducted of seven qualitative papers. In applying a meta-ethnographic approach, three core concepts emerged: 1) Living with the ‘unknown’ and trying to survive; 2) Receiving a diagnosis of ADHD: a blessing and a curse; and 3) Adjusting to the diagnosis and re-evaluating life. The findings highlight the challenges adults encountered, pre- and post-diagnosis and their responses to this, before moving to a position of self-acceptance.

The research paper focused on exploring adults’ prior experiences of living with undiagnosed ASD, including the process of pursuing, receiving, and adjusting to a diagnosis in adulthood. IPA was used to explore adults’ lived experiences and identified four superordinate themes: 1) ‘Lost in space’: Feeling different and like an outsider; 2) The process of pursuing an explanation for the difference; 3) Shock, disappointment, and relief: the emotional responses to receiving a diagnosis; and 4) Adjusting to the diagnosis: rediscovering myself and learning to accept the difference. These findings captured the journey adults embarked on in attempting to make sense of themselves in a ‘neurotypical’ world, including the barriers they had to overcome in the process.

Both experiences of living without a diagnosis of a neurodevelopmental ‘disorder’ and receiving one later in life, represented a ‘trauma’ which stemmed from an awareness of being ‘different’ and not ‘fitting-in’ to a ‘neurotypical’ world. In response to this, adults defaulted to a ‘fight or flight’ position, with the ultimate aim of surviving. These findings illustrate the importance of providing support to the ‘neuro-diverse’ community and raising awareness of their unique attributes to alleviate feelings of ‘difference’.