Analog to digital: artificial intelligence-based anatomic research

Analog to digital: artificial intelligence-based anatomic research

When Casey Holliday and other scientists first started studying anatomy, they had to use scalpels, scissors, and even their own hands. But because of recent technological advancements, Holliday and his colleagues are now able to look inside an animal or a person—down to a single muscle fiber—without ever creating an incision. They achieve this by employing artificial intelligence (AI).

According to Holliday, an associate professor of pathology and anatomical sciences, his lab at the MU School of Medicine is one of just a few in the world that now use this cutting-edge methodology.

AI has the capacity to instruct computer algorithms to recognize a muscle fiber in a CAT scan-like picture.

Then, according to Holliday, researchers may use that information to create in-depth 3-D computer models of muscles to better understand how the body’s muscles interact with one another to govern movement.

When they started researching the force of a crocodile’s bite, Holliday and a few of his current and previous pupils did that later.

“The oddity of crocodile heads is that they are flat, yet the majority of animals who have evolved to bite very hard, such as hyenas, lions, T. rexes, and even humans, have fairly tall skulls because all those jaw muscles are oriented vertically, according to Holliday. They are constructed in such a way that whatever they consume is exposed to a powerful vertical biting force. However, a crocodile’s muscles are positioned more horizontally.”

The researchers may be able to establish how the muscles are arranged in crocodile heads to improve the biting force using the 3-D models of muscle architecture. Currently, a postdoctoral researcher at the University of Chicago, Kaleb Sellers, a former student of Holliday’s, is assisting in leading this project.

“Jaw muscles have long been examined in animals with the assumption that relatively simple descriptors of muscle architecture may tell you a great lot about skull function,” thus according to Sellers. This research demonstrates how intricate a reptile group’s jaw muscle architecture is.

About a decade ago, Holliday’s lab started testing 3-D imaging.

With research in Integrative Organismal Biology that demonstrated the formation of a 3-D model of the skeletal muscles in a European starling, some of their preliminary findings were published in 2019.

Holliday said that historically, anatomical study entailed dissecting animals with a knife or scissors, or what he called a “analog” technique, much like what he did when he was a child. The advantages of utilizing digital photos to study anatomy initially came to his attention when he joined the “Sue the T. rex” initiative in the late 1990s. It is still one of the biggest and best-preserved Tyrannosaurus rex specimens that have ever been found.

Holliday remembers the occasion when the T. rex’s enormous head was shipped to Boeing’s Santa Susana Field Laboratory in California to be photographed in one of the big CAT scanners typically used to examine jet engines on passenger jets.

At the time, it was the only CAT scanner in the whole world large enough to accommodate a T. rex skull and powerful enough to push X-rays through boulders, according to Holliday. After graduation, I considered training to be a radiology technician, but working on the Sue project allowed me to understand all about how something was CAT scanned, and that really piqued my interest.

The “cutting edge” imaging and modeling techniques that he and his colleagues are developing are already being used by many of Holliday’s current and previous students at MU to learn about anatomy. Emily Lessner is one of those students; she recently graduated and credits working in Holliday’s lab sparking her interest in “long-dead creatures.”

Lessner asserts that “The digitization process is used in more than only our lab and research. It helps us to communicate our discoveries with other researchers to advance science more quickly and to make them accessible to the general public as tools for conservation and education.

Particularly, my study of these animals’ soft tissues and bony correlates has not only raised a huge number of unanswered problems but also made clear a great deal of previously unknown information. In this approach, I was able to learn imaging skills that would be useful for my future profession and have access to more opportunities than I could ever explore in a lifetime.

Plans, according to Holliday, are also in the works to extend the use of their 3-D anatomical models by examining the evolutionary development of human hands. Funding from the Leakey Foundation was been awarded to the initiative, which is still in its early phases.

Two of Holliday’s colleagues from MU, Kevin Middleton, an assistant professor of biological sciences, and Carol Ward, a curator’s Distinguished Professor of pathology and anatomical sciences, will work with him on the project.

Despite the fact that around 90% of the research conducted in Holliday’s lab examines contemporary phenomena, he said that the information they gather can also help us understand the fossil record, such as by providing more information about the T. rex’s movements and bodily functions.

The ability of the T. rex to perform fine motor functions and more complex actions, such as bite force and feeding behavior, may be better understood with a greater understanding of actual muscle structure, according to Holliday.

Translate »