Dr David McGrath
Spine Physician
MB BS (Hons) FAFOM, RACP, FAFMMMaster of Pain Medicine
Disturbance Barriers
We can distinguish two types.
1. Fixed
2. Variable
Fixed barriers are designed to EXCLUDE a type of disturbance that is ALWAYS unwelcome. Examples are:
1. Skin with fatty secretions exclude bacteria intrusion
2. IgA secreted into the lumen of the GIT tract and IgE into respiratory spaces to neutralize bacteria
Variable barriers are designed to EXCLUDE under some conditions while ADMITTING under other circumstances.
1. Eyelids open and close, depending on the strength of the corneal and retinal stimulation.
2. Nervous system DISTURBANCE depends on the CURRENT state of activation of the nervous system. (EMOTION)
(to be continued)
©Copyright 2007 Dr David McGrath. All rights reserved