Biomedical Engineering Reference
In-Depth Information
consideration that the ball might roll in your direction and that a child
may run after it. Good drivers anticipate in such a way, by changing
the speed and the route, that they can avoid the ball and children in all
possible cases. That is the core of building in safety margins.
By building in safety margins, the modern human brain has devel-
oped itself as a long-term planner and has incorporated risks as an
integral part of life. The safety margin needs to consider not only what
is there here and now but also what could be there and then. Our sys-
tem is not built to prevent all hazards but to find an optimum level of
risk taking.
2.4 STAGE 4, FROM 10 THOUSAND TO 200 YEARS AGO
—
THE
DEVELOPMENT OF RISK TOLERANCE
In the latest stage of evolution, theBronze(10,000to7,000years
ago) and Iron Ages (from 7,000 years ago), our environment changed
rapidly, and the brain was able to adjust to this only to a small
extent.
became farmers and were able to produce many
tools. All over the world, they created settlements in fertile areas.
Suddenly, it became possible to acquire property. Competition for
the same land led to wars. Within settlements, some of the previous
natural dangers were present only in mild forms. The control of food
production increased, and planning became more important. Man
became the biggest risk. Compared to the previous periods, most of
the conditioned alarm systems were hardly activated. The danger
arousal and anxiety systems in the brain developed a high level of
risk tolerance to the relatively few risks still present. We mostly felt
unsafe when meeting fellow citizens who appeared different. We still
associated them with members of different tribes that could steal
food or our children. The most common stimuli didn
Homo sapiens
telicitanxiety
anymore. Our warning systems had become lazy, and we became
quite tolerant of possible risks in our environment. In modern safety
management, we have to compensate for risk tolerance. The lesson to
be learned here is that we have a tendency to stay in our comfort
zone, even if this is not appropriate.
'
The brain has developed a tolerance against risks.
