- seCtIon tHRee: BoDY AnD WoRLD
ACtIVItY 9.1
Getting out of bed on
a cold morningTry William James’s famous meditation (as he called
it) and watch what happens when you get out of bed
on a cold morning. If you don’t live somewhere cold
enough, just choose a morning when you really don’t
want to get up. Alternatively try getting out of a bath
when the water is going cold and you’ve been in there
too long, or out of a hot shower when you’re really
enjoying it.
Watch what happens. What thoughts go through your
mind as you struggle to get out? What emotions do
you feel? Do you speak to yourself or try to persuade
yourself? If so, who or what is struggling against
whom or what? What happens in the end? You might
like to write a short description as James did (1890, ii,
p. 524–525).
Comparing descriptions can make for a lively class
discussion. What are the implications for free will?We can look to see which parts of the brain and the rest of the
body are involved in such decision-making and, in principle at
least, trace how they lead to particular decisions and actions.
But is this any different from exploring Google’s search algo-
rithms to see how it chose which list of links to show me when
I asked it ‘what is consciousness?’? Google’s choices, we may
assume, are fully determined by its fiendishly complicated
algorithms so it could not, in those circumstances, have done
otherwise. Does Google need consciousness?THE NEUROANATOMY
OF VOLITION
Consciousness may feel like the cause of voluntary action, but
when we look inside the brain, we see lots of areas involved
in carrying out the different phases of a voluntary action (see
Haggard [2008, pp. 937–938] for simple models of the circuits
and the phases). An obvious question to ask is where, if any-
where, does consciousness come in?
An extensive network of brain regions in the medial and lat-
eral frontal cortex, as well as the parietal cortex, are thought
to be related to ‘internally guided’ behaviour (Brass et al.,
2013). Multiple areas of neural activity converge on primary
motor cortex, which carries out motor commands by sending
signals through the spinal cord to your muscles (Spence and
Frith, 1999). There are different pathways for ‘internally’ and ‘externally’ triggered
actions, although really there is a continuum between the two (Haggard, 2008).
Externally triggered actions show activation in the cerebellum and premotor cor-
tex. Intentional actions correlate with activity in prefrontal regions. These include
the supplementary motor area (SMA) involved in the sequencing and program-
ming of motor acts to fit a ‘motor plan’; the preSMA, which may be the source of
the early part of the readiness potential (the activity leading up to the muscle
movement); and the anterior cingulate, a complex area involved in emotion and
pain as well as attention to, and selection of, information needed for action. There
is also Broca’s area (in the left inferior frontal gyrus in most right-handed people),
which produces the motor output for speech.
Some of this is known from the effects of brain damage – for example, from
the famous case of railroad worker Phineas Gage. In 1848 a tamping iron was
blown straight through his frontal cortex, leaving him a changed personality
and no longer able to behave responsibly (Damasio, 1994). Damage to dor-
solateral prefrontal cortex can lead to a lack of spontaneous activity, and to
repetitive, stereotypic actions. People with lesions in the preSMA are prone
to automatic actions in response to environmental triggers, as though unable
to stop themselves eating an apple they see in front of them, or putting on a
garment because it’s there. Lesions of the prefrontal region and corpus callo-
sum can produce the extraordinary complaint of ‘alien hand’, in which patients
say that their hand has a will of its own. Damage to only the corpus callosum‘All theory is against the
freedom of the will; all
experience is for it’
(Samuel Johnson, 15 April 1778,
in Boswell, 1791/1952, p. 393)