Ashley specializes in Anglo-Saxon art and examines early patristic writings on the five senses and the application of this doctrine within specific contexts in Anglo-Saxon Era England, from the 7th to 11th centuries. Her work interfaces with the study of the five senses and the body in later Medieval art by considering its beginnings in the Late Antique and Early Medieval era.

Her dissertation focuses on monstrosity in a series of case studies, looking at the range of monstrous forms present in Anglo-Saxon art and literature and in particular the ways in which monstrosity can develop our understanding of conceptions of the body, the five senses, and spiritual practices in Anglo-Saxon England. Case studies from her dissertation include the monstrous initials in the Lindisfarne Gospels, select objects from the Staffordshire Hoard and their roles as both spiritually and physically protective objects, the Wonders of the East text and accompanying images in the Cotton MS. Tiberius B. V. a secular, scientific manuscript that looks to foreign cultures and the distant lands of the East as a way of understanding social, bodily, and religious difference, and 11th-century, Anglo-Saxon hell-mouth imagery that depicts the physical torments of damnation in judgement scenes and scenes depicting the battle for souls.

Ashley is interested in understanding the ways in which Anglo-Saxons grappled with boundaries between the self and God, the physical body and the spiritual world, England, the Holy Land and other distant lands, the monstrous and human, and the fluid areas of identity that lurk behind the images of the monstrous in Anglo-Saxon era. She is also interested in tools, processes of production, and material as intrinsically meaningful and often supportive of iconography in religious art.