BackgroundI know our bodies have a handful of ways to threshold our awareness of sensory stimuli:
- Sensory acuity
- I assume really tiny stimuli could fit between receptors
- e.g., Oaklander (2001) found nociceptor densities of 2-4000/mm2
- Impacts summative abilities to surpass postsynaptic impulse thresholds
Varying thresholds of individual receptors.
- Dubin & Patapoutian (2010), for example, show variations in classes of neurons based on their temperature (°C) and mechanical force (milli-newtons) thresholds (see thresholds listed in Tables 1 and 2).
Reticular formation involvement in regulating what we are consciously aware of
Which of the above physiological mechanism(s) are primarily responsible for our lack of sensation (or lack of conscious awareness) regarding microbes on our skin?
Update: My question is explicitly about physiology. Regardless of the impacts, benefits, evolution ,etc. of not feeling them, they're there. But even though we're covered in microbes, we don't sense them -- how not? I want to know by what physiological mechanism(s) we don't feel microbes on our skin.