Figure 2.

Strategies for regenerative medicine

Two fundamental broad approaches toward the control of biological function in biomedicine. The first (A) focuses on the structure of a specific pathway and seeks to enhance functionality or repair a disease state via hardware rewiring—adding or deleting nodes or changing relationships between nodes. In practical terms, this means gene therapy (e.g., CRISPR) to modify the pathway at the lowest level of control. The second, elaborated in this perspective (B), sees function as the interplay of a pathway machine with its context, using multi-scale relationships with other components of the body to pursue anatomical or physiological goal states. This leads to the specific and testable proposal that optimal control over system-level phenotypes can be exerted using techniques from a discipline ideally suited for control of fundamentally multi-level phenomena: behavioral neuroscience. Image used with the permission of Jeremy Guay.