When Linda Sanet and Sue Barry speak, I pay close attention. So it was early this morning, when a subject that came up regarding binocular vision, that one of the world’s most obscure inventions came to mind. Jeopardy bonus points will come your way one day if you file away this picture of The Lyman Dingbat in your head.
Although no one seems to know the origin of the term, The Lyman Dingbat was the personal invention of an experimental psychologist, Adelbert Ames, Jr., who is widely known outside of Optometry for his elaboration of optical illusions. Ames was iconic in Optometry in the mid 1900s for his design of the leaf room to detect aniseikonia, and his collaboration with Paul Boeder and Robert Bannon at The Dartmouth Eye Institute to design eikonic spectacle lenses. Ames designed the Dingbat, a rotating type of Galilean telescope, to help compensate his significant cyclophoria associated with facial asymmetry and maintain fusion. I’ll have more to say about the role of prisms and optometric vision therapy in a subsequent blog.
You can envision why Ames had cyclophoria, looking at this photo in which his right eye slopes toward his right ear and lowered right shoulder – in essence everything on his right side sloping downward from the horizontal plane relative to his left side. The most exaggerated form of cyclophoria or tropia occurs in congenital superior oblique paresis or palsy. Midfacial hypoplasia occurs, with the more shallow side of the face in the same direction as the head tilt (see here). Facial asymmetry reportedly occurs in 75% of the cases of congenital SO palsy.
What causes the hypoplastic and smaller side of the face? There are two main theories, one involving a gravitational pull on one side of the face, and the other positing that this is an associated mild form of cranial plagiocephaly. Viola Frymann, a renowned osteopathic physician, advanced the association between skull deformities, facial asymmetries and strabismus, and the potential indications for osteopathic interventions.
Ames was a fascinating individual, and thinking back to the Lyman Dingbat prompted me to order a copy of a biography about him written in 2006 that has a chapter on the subject. From the Amazon description of the book:
Adelbert Ames, Jr. (1880-1955) was the creator of some of the most memorable scientific demonstrations of the 20th century. He created rooms where small children tower over their parents, demonstrations where playing cards and cigarette packs and matchbooks seem to change size and position in the blink of an eye. These demonstrations, dazzling and delightful as they are, were created with the intent of communicating Ames’s serious perceptual theories and philosophical ideas. In this book, W.C. Bamberger traces the life and work of this artist-cum-philosopher and his quest to unite the studies of biology, memory and perception with his idea of “becomingness”-the idea that all of us are in every moment recreating ourselves through every perception and experience we have-a fact that Ames viewed as central to all our lives.