Biomedical Engineering Reference
In-Depth Information
Figure 10
. Complex Adaptive Systems (CAS) Schema. Many natural systems (e.g., immune,
nervous system) are characterized by a behavior that is emergent as a result of often nonlinear
spatiotemporal (complex) interactions among a large number of component "parts" at differ-
ent levels of organization. The three principal inputs that drive the dynamics of the CAS are
information, matter, and energy. These systems tend to be nested and open to the environment
(have history); the parts cannot contain the whole; they are relational (short-range acting);
nonlinear; contain adaptive feedback loops (anticipatory) with boundaries that are difficult to
demarcate before. (Artwork by M. Clemens.)
physiological time-series data seem to be restricted in dimensional complexity to
3 to 6 degrees of freedom (see chapter 3.3 [by Glass], part III, this volume). The
whole-part dualistic nature of subsystems (e.g., heart), comprised of multiple
nested loops of nonlinear interacting regulators (homeostats), make them espe-
cially suitable/prone to chaotic behavior and thus amenable to finer/rapid con-
trol/adaptation (12).
6.1. The Living Organism as a Unit of Biological Organization
The questions that persist about biological functions and their interrelation-
ships are:
& Does life get more complicated? i.e.,
more effective func-
tions are associated with more complex structures whereas
diseases and death are the converse
.
