Scince
I'm
not guilty but
my brain is
A
leading neuroscientist caused a sensation by claiming crimes
are the result of brain abnormalities. LAURA SPINNEY
investigates a slanging match between scientists and philosophers
Last
month, the case against Patrizia Reggiani was reopened in
Italy. She is serving a 26-year jail sentence for having
ordered the killing of her husband, the fashion supremo
Maurizio Gucci. At the first trial in 1998, expert witnesses
dismissed her lawyers' claims that surgery for a brain tumour
had changed her personality. The new trial has been granted
because her lawyers believe that brain imaging techniques
developed since then will reveal damage that was previously
undetectable, and strengthen their case for an acquittal.
The
idea that someone should not be punished if their abnormal
neural make-up leaves them no choice but to break the law
is contentious but not new. However, one prominent neuroscientist
has sparked a storm by picking it up and turning it round.
Writing in the Frankfurter Allgemeine Zeitung, one of Germany's
leading newspapers, Wolf Singer argued that crime itself
should be taken as evidence of brain abnormality, even if
no abnormality can be found, and criminals treated as incapable
of having acted otherwise.
His
claims have brought howls of outrage from academics across
the sciences and humanities. But Singer counters that the
idea is nothing but a natural extension of the thesis that
free will is an illusion - a theory that he feels is supported
by decades of work in neuroscience.
The
head of the Max Planck Institute for Brain Research in Frankfurt,
Singer is best known for his work on the so-called binding
problem of perception. This is the conundrum of how we perceive
an object as an integrated whole, when we know that the
brain processes the various elements of it - colours, angles,
and so on - separately. His group was among the first to
suggest, and then demonstrate, that the answer lay in the
synchronisation encoding the separate features. He has since
extrapolated those ideas to the process by which we make
decisions, which has led him to question whether we are
really the free-acting agents we imagine ourselves to be.
His
argument goes like this. Neurobiology tells us that there
is no centre in the brain where actions are planned and
decisions made. Decisions emerge from a collection of dynamic
systems that run in parallel and are underpinned by nerve
cells that talk to each other - the brain. If you look back
in evolution to say, the sea slug Aplysia, you see that
the building blocks of this brain have not changed. The
amino acids, the nerve cells, the signalling pathways and
largely the genes, are the same. "It's the same material
[in humans], just more complex," says Singer. "So
the same rules must govern what humans do. Unavoidable conclusion."
He
argues that the human brain has to be complex to compute
all the myriad variables that influence each decision we
make - genetic factors, socially learned factors, momentary
triggers including commands and wishes, to name a few. And
because it considers most of those variables at a subconscious
level, we are not aware of all the factors that make us
behave in a certain way, just as we are not aware of all
the elements of an object that are processed separately
by our visual brains. As humans, however, we are able to
extract some of those factors and make them the focus of
attention; that is, render them conscious. And with our
behaviour, as with the world we see, we yearn to build a
coherent picture. So we might justify our decisions in ways
that have nothing to do with our real, subconscious motivations.
The
most striking example of this is hypnotism. Singer himself
learned how to hypnotise while a student at Cambridge University.
At a party, he instructed a Royal Air Force pilot to remove
the bulb from a light fitting and place it in a flowerpot,
on hearing the word Germany. The pilot did so in mid-conversation,
much to the amusement of the onlookers. They were amateurs,
they didn't debrief him properly. And when they told him
what he had done, because he had no recollection of doing
it, he was extremely disturbed.
According
to Singer, what the pilot did is explained by the structure
of his brain and its inherent weakness, if you see it as
a weakness to be susceptible to hypnotism. The same goes
for a murderer or a thief, he says. We live in a society
where people whose behaviour is considered to deviate from
the norm - as determined arbitrarily by that society - answer
to the justice system. But the way they are treated by that
system is, he believes, inconsistent.
If
some abnormality is found in a person's brain, the doctor's
report is submitted as mitigating evidence and the defendant
may be treated more leniently. If nothing is discovered,
they are not. Take the case of the British man who terrorised
200 officials because he thought they intended to have him
sectioned under the Mental Health Act. Psychiatrists found
no sign of a mitigating mental illness, and he was jailed
for life. But, Singer says, if a person does something antisocial,
the reason for it is in the brain. The underlying cause
may be a twist in a gene, or a tiny hormonal imbalance that
cannot be detected with current technology. "It could
have multiple reasons," he says. "But these reasons
must all manifest themselves in brain architecture."
In
practice, he says, the change in thinking he advocates wouldn't
change the way we treat criminals all that much. People
considered a danger to society should be kept away from
society, re-educated as far as possible and in cases where
this is not possible, simply kept away, as they already
are. But he would like to see the courts place less burden
on psychiatrists, who are not capable of identifying all
the subtle structural changes that lead individuals to behave
as they do. "As long as we can't identify all the causes,
which we cannot and will probably never be able to do, we
should grant that for everybody there is a neurobiological
reason for being abnormal," he says.
He
does not argue that a criminal should not be held responsible
for their crime. After all, if a person is not responsible
for his/her own brain, who is? Neither does he argue that
we should do away with concepts of good and evil. "We
judge our fellow men as either conforming to our rules or
breaking them," he says. "We need to continue
to assign values to our behaviour, because there is no other
way to organise society." However, he does argue that
when people commit crimes, they are not acting independently
of the nerve cells and amino acids that make up their brains,
and that behave according to certain deterministic principles.
One
important implication of his argument is that treatment
meted out to offenders should be less about revenge and
punishment, and more about assessing their risk of re-offending,
given the brain they have. Of course, this already happens.
If a woman has been driven to a crime of passion after severe
provocation, having otherwise lived an exemplary life, she
is considered less of a danger to society than a man who
has frequently abducted teenage girls, raped and murdered
them. Another corollary of Singer's ideas that he recognises
will be harder for people to swallow, is that the consequences
of a crime should be considered less important than they
are, since an individual can only control his own actions
and not those of others. For example, a driver seen running
a red light should be treated the same way whether or not
he hit the child who, unseen from the wheel, stepped into
the road at the same moment.
"Breathtaking,"
is how Ted Honderich, a philosopher at University College
London, scathingly describes Singer's foray into traditional
philosophical territory. Honderich says philosophers have
discussed different definitions of freedom for centuries,
one of which is perfectly compatible with the sort of determinism
Singer describes. That is, if free action is defined as
action caused by your character - whatever hereditary and
environmental influences contributed to that character -
then you are free even if your brain does resemble that
of a slug.
And
although the discussion might appear to have degenerated
into a slanging match between scientists and philosophers,
neuroscientists have also criticised Singer. "We don't
know enough to make such conclusions," says Cornelius
Weiller, an expert in brain imaging at Hamburg University.
Singer is right, he says, that there is no homunculus in
the brain, making our decisions for us. But the question
remains, how do all those parallel computations become integrated,
and how does the self feel that "I" made the decision?
Science has yet to answer the binding problem of decision-making.
In
response to the accusation that he is rehashing old ideas,
Singer points out that the German newspaper debate got under
way without him, and he was merely responding. So the more
interesting question, perhaps, is why the public is interested
again now. One reason, he thinks, is that people look at
their societies, see that the totalitarian ones failed,
and realise that the most complex are self-organising and
impossible to steer or control. "You free yourself
from authorities, including the gods, but you find yourself
part of an evolving system," he says. "Now you
realise that you don't really have influence on the dynamics
of the systems in which you are. I think this gives a feeling
of helplessness."
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(R) thedailystar.net 2004
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