Page 74 - BBC Focus - August 2017

UNDERSTAND
PAIN
In one tweet…
Pain, as an alarm, is essential for survival. Chronic
pain is bad and millions suffer, but scientific
discoveries bring hope.

2 the spinal cord to the brain, a large
network of brain regions is
activated, including the brainstem,
the thalamus and several regions of
the cortex. The subjective experience
of pain then emerges from this
brain activity.
Until the conscious brain processes
these incoming signals, we don’t
actually call it pain, but nociception
– this is the nervous system’s
response to the original tissue
damage. The relationship between the
extent of tissue damage and the
amount or quality of pain that the
person actually feels is not a simple s
one-to-one mapping. Incoming
signals can be amplified, attenuated
or reappraised by the brain, which
can dramatically change the
individual’s experience. So, being sad
about your pain or being anxious at
the dentist really will make it worse
– emotions are like amplifiers in your
brain, turning up the volume of pain.
Thankfully, we also have an inbuilt
system to lessen pain. The brain
system that’s responsible for the Pain signals arrive at the brain via the spinal cord
feelings of pain can talk to the spinal
cord and suppress nociceptive so on – and it doesn’t need a fully- A staggering one in five adults
signals, like a brake. This results in developed brain to take place. experiences it. It lasts, on average, for
less brain activity and less pain, at seven years, but for 20 per cent of
least until the brake is removed. This What is the difference between people it’s more than 20 years, and is
is what goes on in athletes and physical and emotional pain? more prevalent in women and the
soldiers during situations of high Historically, if people reported pain elderly. Chronic pain wreaks
arousal and battle, or when someone in the absence of an injury, it was suffering on patients and their
is distracted from their pain (for called ‘psychogenic’ pain – a families. It also brings significant
example, a parent desperately pejorative term due to a flawed costs to society, estimated annually at
distracting their child from the understanding of the mechanisms €200bn in Europe and $600bn in the
dreaded vaccine jab). It’s not a trick, involved. Emotional pain also has a US. Additional problems like
but real physiology. In fact, it’s this neural basis, and there are even depression, anxiety and sleeplessness
system, called the ‘descending pain overlaps with some brain regions can add to the suffering.
modulatory system’, that’s hijacked involved in physical pain. Chronic pain is one of the largest
when the placebo effect acts to reduce Understanding the basis of someone’s health problems worldwide, and
pain. This is known as ‘placebo pain is important if we’re going to current treatment options do not
analgesia’. help them. For example, is the pain provide adequate relief to the majority
Weirdly, it was once thought, not due to inputs from the body, or has of patients. Patients with chronic
too long ago, that because animals the brain generated an experience pain might have different conditions.
and babies have less developed brains independently? We shouldn’t think Nerve damage due to diabetes, being
than adults, they cannot feel pain. that physical pain is more ‘real’ or on chemotherapy, multiple sclerosis,
This is complete nonsense. Pain is an important than emotional pain. sustaining an injury, phantom limb
individualised and subjective pain, or arthritis, are a few examples.
experience that depends upon a What is chronic pain? Yet the signs and symptoms that
person’s mood, how much attention This is the system gone wrong. It’s patients describe are often similar.
they give to it, the context of the defined as pain that persists We are starting to consider chronic
situation in which they are hurt and beyond normal tissue healing time. pain as a disease in its own right,

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