36 | New Scientist | 9 November 2019
And for treatment-resistant IBS, there is
overwhelming evidence that hypnosis
can improve symptoms and quality of life.
“During hypnosis, patients might picture
the gentle waves of the sea, and imagine their
bowels are moving in a similar regular, quiet
rhythm,” says Carla Flik at University Medical
Centre Utrecht in the Netherlands.
In the US, both the American Psychological
Association and the National Institutes of
Health now promote hypnosis as part of
standard care for pain. Numerous studies have
shown that it can improve a variety of chronic
problems, such as lower back pain and side
effects of cancer treatments – often offering
more relief than physical therapy and cognitive
behavioural therapies alone.
Hypnosis can be so effective for pain
relief that, since 1992, it has been used
in many surgical procedures – including
biopsies, laparoscopies and plastic surgery –
as an alternative to general anaesthesia.
The technique is simple, says Aurore Marcou
at the Curie Institute in Paris, France. “The
patient receives a local anaesthetic and mild
sedation. We sit beside them and guide them
to concentrate on their inner world, their
breathing, and help them bring their
attention to a safe space. We help them
relive experiences in the past. All of your
brain is focused on those memories.”
The major benefit is fewer side effects.
“You don’t feel drowsy, or sick from the general
anaesthetic,” says Marcou.
Guy Montgomery at the Icahn School of
Medicine at Mount Sinai, New York, has found
that women who had hypnosis before breast
cancer surgery reported less pain, anxiety,nausea and fatigue afterwards. And the
benefits weren’t just physical. His team
predicted that if 90 per cent of people
needing a breast cancer biopsy in the US
were to undergo hypnosedation, it would save
the country more than $135 million a year.Going deeper
This reported reduction in mental and physical
symptoms makes it no surprise that pregnant
women like Shona flock to hypnobirthing
classes. Officially, though, the jury is still out on
this one – a 2011 review of 13 studies concluded
that hypnobirthing “holds promise” as an
intervention for labour pain, but so many of
the trials were poorly designed that a more
definitive answer wasn’t possible. A 2015 trial
found the technique made little difference to
whether women requested pain relief duringBURGER
/PHANIE/SCIENCE^ PHOTOLIBRARYchildbirth, but it did significantly reduce their
reported levels of fear and anxiety.
Indeed, many see promise for its use in
mental health. Anxiety disorders are some of
the most impairing and common conditions
in the US. This year, in the first analysis of its
kind, Keara Valentine at the University of
Hartford, Connecticut, and her colleagues
quantified the effect of hypnosis for reducing
anxiety by analysing all of the controlled
studies of this intervention. The results were
impressive: the average participant receiving
hypnosis showed more improvement than
84 per cent of people who didn’t receive it.
What’s more, there was no difference in benefit
between those who used self-hypnosis and
those given guided hypnotherapy.
Hypnosis isn’t just used for pain and anxiety,
of course. It is increasingly popular as a way to
help people learn new behaviours or kick bad
habits. But, again, the research is mixed
because of poor trial design. In June, Jamie
Hartmann-Boyce at the University of Oxford
and her colleagues published a review of
14 studies analysing the use of hypnosis to
help people give up smoking and couldn’t
find sufficient evidence to recommend it. The
problem wasn’t that hypnosis definitely didn’t
help, she says, but that the trials were a mess.
“They had lots of bias, were imprecise or had
too few participants,” Hartmann-Boyce says.
“It’s such an important issue that we need to
produce bigger, better trials.”
In other areas, results are more consistent.
For instance, in the early 1990s, a meta-analysis
of weight-loss studies showed that adding
hypnosis to cognitive behavioural therapy
more than doubled how much weight people
lost. Another meta-analysis done in 2018 had
equally encouraging results.
Despite this increasing evidence ofNHS trusts
now offer
hypnobirthing
coursesNo hypnotist can make
you do something against
your will, despite what TV
mentalist Derren Brown’s
stunts may suggest. Back in
1939, scientists did show
that hypnotised volunteers
would perform risky acts, like
picking up poisonous snakes,
suggesting they weren’t
acting of their own volition.
But later experimentsrevealed that most people
would do these things
whether hypnotised or not,
merely because they had
been put under pressure by
a person in authority. When
asked to perform the same
acts outside such settings,
participants all said no.
“It’s true that the people
who are brought on stage
and hypnotised feelcompelled to behave in the
way they do,” says Michael
Heap, a clinical psychologist
at the University of Sheffield,
UK. “Mainly it’s because
these people are placed in
front of an audience. They
know what’s expected of
them. They’re actually just
obeying the hypnotist,
they’re cooperating,
complying with authority.”Smoke and mirrors