Page 45 - Control Theory in Biomedical Engineering

32 Control theory in biomedical engineering

Fig. 28 Biofeedback therapy.

over such things as heart rate (Wheat and Larkin, 2010), muscle tension,
blood flow, pain perception and blood pressure. This process involves being
connected to a device with electrical sensors that provide feedback about
specific aspects of your body, as described in Fig. 28. This technique is
adopted in many clinics and hospitals (Badawi and El Saddik, 2020). Novel
research aims to utilize this technique outside clinics and hospitals to benefit
patients and healthy individuals.
Alternatively, in the physiological regulation, the concept of homeostasis
has undergone considerable revision. This new revision is characterized by
more contemporary definitions for this concept. An example of a revised
concept is allostasis, which is considered as an alternative view offering novel
insights relevant to efficiently regulate physiology and human behavior
(Ramsay and Woods, 2014). In fact, allostasis reflects the process whereby
the human physiological systems must be able to be adaptive to internal or
external stimulation by adjusting one or more regulated parameters
(Berntson et al., 2016). Indeed, the brain first detects stimulation and con-
sults its database, then it computes the best response (Schulkin and Sterling,
2019). Thus, the control center (brain) adjusts in real time to the dynamic
flows of energy and nutrients that reduce prediction errors for better adap-
tive control. For that, allostasis is now considered as a core principal in phys-
iological regulation. However, there are still many challenges to using
allostasis due to its significant computation costs.