Last summer during my vacation in the
the highest disability worldwide.² But why do
French Alps I was making coffee, the old
people still feel pain, far beyond the healing
fashioned way. I sat in an uncomfortable
period of the initial injury?
campstool while stabilizing a thermos with my feet and poured boiling water into the
To understand the ambivalent role of pain, it
filter. Everything went well, until a horsefly
is important to explore the pain mechanism
decided to prey on my left foot. I was start-
itself. Below, I will briefly outline various
led by the sudden sting, accidently dropped
important components of this network and
the thermos and jumped up to prevent the
highlight psychological factors that are invol-
stream of outflowing coffee to touch my
ved in pain experience.
feet. For one moment I was satisfied by my quick response to this threat, but a burning
René Descartes’ pain
pain reminded me I was still pouring boiling
The example above relates to many painful
water from the cattle, only this time over my
experiences that we all have experienced:
hand and leg.
cuts, burns, strains, fractures, and other forms of injury and illness are part of our
This situation illustrates the vital importance
lives. In most of these occasions, our pain
of pain as an indicator of danger and thereby
system functions in accordance with our lay
as a system that contributes to survival. In
conception. That is, sensors in our skin (i.e.
response to this threat, I probably broke my
nociceptors) detect tissue damage and trans-
personal sprint record to reach the sanitary
port a ‘pain signal’ through our spinal cord to
building in desperate need for cooling.
our brain leading to pain. Subsequently, this
Furthermore, the rest of my vacation only the
signal will immediately direct our attention
slightest touch reminded me of my burned
towards the endangered area and motivates
skin, which facilitated protection and - more
us to protect the painful tissue. This simple
importantly - I outsourced coffee making to
model of pain is nicely illustrated by René
my more motorically gifted girlfriend.
Descartes (figure 1). In this situation: Harm causes hurt.
Despite the irrefutable benefits, pain is not always a useful indicator of danger as in the
Hurt does not equal harm
example above. In contrast, approximately
Although the ‘Descartes’ model’ can account
20% of the human population suffers from
for the immediate pain that I felt when the
long lasting (i.e. chronic) pain that often has
boiling water touched my skin, it fails to
a severe impact on daily life functioning. For
explain why even the slightest touch of the
example, many patients with chronic pain
burned skin in the days after the accident
report difficulties with attending social activi-
- which is not a damaging stimulus - still
ties (48%), sleep (65%), walking (47%), and
caused pain. An alternative way to explain
maintaining relationships with friends and
this ‘hurt without harm’ phenomenon, is to
family (27%). ¹ It is therefore not surprising
assume that the sensitivity of our nervous sys-
that back pain alone is ranked by the World
tem that transports signals from skin to brain
Health Organization as the illness that causes
can be modified. Indeed, many experiments
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