My name is David Adam. I'm a journalist
and I have obsessive-compulsive disorder.
Lots of people say oh I'm a bit OCD but
unless you have it it's almost
impossible to comprehend just how severe
and crippling a condition it is. OCD can
make people wash their hands for hours
bleach until they're red raw. It can
maybe we'll check the front door is
locked 20, 30, 40 times before they leave
the house or maybe stop them leaving the
house at all. My own OCD is around HIV
and AIDS. From the moment that I woke up
until the time I would go to sleep, I was
consumed by repetitive, irrational
thoughts about how I might have caught the
disease. So I lived to that years and it
was only really when I started to
involve my daughter in my rituals and
project some of my fears onto her that,  I
went for help. I was lucky a
combination of medication and the
counseling that I received helped me keep
my condition under control.
When I started to feel a bit better I
think I reacted like a journalist
probably would and I wanted to know more
and to write about what had happened.
I wrote a book about my own experiences
which with OCD and the science and the
history of it but one of the things that
I didn't really address was the use of
animals to research the condition. I
think that's because I thought well what
can an animal's brain even a monkey's
brain tell us about what goes on inside
a human.
I've been invited to the University
of Cambridge to meet Professor Trevor
Robbins, a world expert on the science
behind OCD. He's offered to take me
behind closed doors to see how his team
studies the disorder.
OCD of course
is a psychiatric disorder which consists
of obsessions that's thinking the same
thing over and over again, often worrying
about it and compulsions which is doing
the same thing over and over again to no
good effect. Actually it's useless actually it's
incredibly disruptive of your life. This
is a very severe disorder and
understanding it is absolutely vital for
the future of psychiatry.
So two structures in particular in the brain
which seem to be involved in OCD
are the frontal lobes and they're
what here? They're all over here they're
huge in humans as you know and the
frontal lobes are composed of many
different areas which have different
functions. These are some of the most
mysterious parts of the brain and it's
only gradually that we're becoming to
appreciate and understand their
functions. The frontal lobes have very
important roles in controlling this very
important set of structures and in the
it's like a  fist in the hand of the brain.
This is this would be the cortex
including the frontal lobes and this
some of these structures are called the
basal ganglia and they go wrong in
conditions like Parkinson's and
Huntington's
but they've also been implicated in
addiction and also in OCD.  And somehow it
looks to us as though the relationships
between these structures the frontal
lobes and the basal ganglia are changed
in OCD. Now there may also be some
chemical changes associated with this
because there are chemical messengers
which modulate the functions of these
structures according to our moods, our
stress state and so-forth. These include
substance things like dopamine and
serotonin and one of the treatments as
you know that's been used in OCD is to
boost serotonin which to be honest has
not been that successful but it may help
some patients. Also dopamine, it's been
suggested to be too active in some
patients and so some drugs which
antagonise the effects are definitely
have been helpful in some severe cases.
As you know the other ways of treating
OCD are the talking treatments CBT and
also rather radically the deep brain
stimulation which is as you know only
used very severe cases which again does
depend on affecting the circuitry of
these structures in very particular ways.
So we see the symptoms of OCD in
humans how do you recreate or model
these in in animas.l Well the main
symptoms of course are the obsessions
obsessional thoughts which are very hard
to model directly in animals because
they can't talk to us but you can
measure the compulsions, the behaviours
that occur repetitively and in a very
disruptive fashion to ruin these
people's lives. You can actually do that
in a very simple way in the genetic
models OCD in the mouse.  So
some of these mice that have an abnormal
protein in the basal ganglia groom
themselves compulsively to a degree
where they cause skin lesions, damage
themselves which is obviously not good
but it's very parallel to
we've seen some patients without she
calls lesions for their hands. So that's
a very direct example another example be
checking behaviour. So patients may check
the repetitively whether they've
locked the door and this is incredibly
disruptive if they spend an hour to
doing that, they're late for work -  lose
their job. And you can measure checking
excessive checking in animals in very
clever ways but you could also get also
some of the thinking possibly no CD
which you can infer from studying the
behaviour of OCD patients and animals. So
you can present animals with situations
where they have to show flexibility in
their responding, in their attending to
the world. You change the situation and
in fact you can use more or less the
same test in animals and humans and show
that patients with OCD are also bad and
flexibly adjusting to changes in the
world in a similar way to animals but
the differences-  in the experimental
animal were able to understand the
mechanisms by which this rigidity occurs
which we can't in humans because we
can't use interventional techniques to
test the causality of the involvement of
that area in thinking or behaviour.
During the next film I look at how Cambridge
researchers are studying OCD using
animals-  the laboratory rat
more controversially, a small species of
monkey known as a marmoset.
