THE ROUGH GUIDE TO PSYCHOLOGYworking out the cognitive processes that underlie consciousness. For
example, there are obvious links between attention and consciousness
whereby we tend to be conscious of those things that we pay atten-
tion to. Related to this are the neural correlates of consciousness. We
can study brain damaged patients to find out which brain areas and
biological systems are necessary for a person to remain conscious.
From this we’ve learned that consciousness doesn’t reside in any one
particular brain structure but instead reflects distributed activity across
the brain. A network involving the thalamus and the cortex seems to be
particularly important.
The so-called “hard problem” of consciousness, by contrast, refers to
the puzzle of how the brain can give rise to first-person experiences such
as what it feels like to stroke a dog, or why red has that redness about it.
From this flow all sorts of philosophical problems – for example, how
do we know that anyone else truly has these phenomenological experi-
ences? Perhaps they go through the motions of responding to incoming
sensory information and expressing their thoughts and feelings but, like
zombies, don’t actually experience that subjective essence of being. The
attitude of most leading researchers in this field is that by untangling the
cognitive and neural mechanisms underlying consciousness we might
find that the “hard problem” evaporates.
An exciting breakthrough in recent years has been the use of brain
imaging to detect signs of consciousness in patients diagnosed as being
in a persistent vegetative state (PVS), a form of waking coma in which
consciousness is presumed to be absent. In 2010, Martin Monti and
colleagues communicated with a PVS patient by asking him simple ques-
tions, such as “is your father’s name Alexander?”, and instructing him
to visualize playing tennis to indicate yes, or imagine walking around
his house to indicate no. These two mental tasks triggered contrasting
patterns of brain activity, and scans of the patient’s brain suggested he
was following the instructions and answering the questions correctly.
It’s hoped this approach could in the future be used to aid diagnosis and
help find out patients’ needs.
The brain on stand-by
In the early 1990s, the pioneering neurologist Marcus Raichle and his
colleagues identified one of the most intriguing functional networks in
the brain – a suite of regions (parts of the prefrontal cortex, the midline
and the parietal and temporal lobes) that grew more activated the less a