Consciousness

• seCtIon tWo: tHe BRAIn

Pain - has an Element of Blank -

It cannot recollect

When it begun - Or if there were

A time when it was not -

(Emily Dickinson, The Poems of Emily Dickinson, 1999 [1890], pp. 339–340)

But what if you have no arm? Amputees who experience phantom limbs some-

times suffer excruciating pain in a knee, elbow, or finger that doesn’t physically

exist. Their pain feels as clearly physically located as yours does.

We began with ‘pain hurts’, but perhaps we should say ‘pain hurts me’. What makes

pain painful is the fact that I don’t like it; that it’s my pain and I wish I didn’t have it.

Can there then be pains without selves who feel them? And if a self is needed, just

how much of a self, and what could the NCs of those necessary selves be?

Consider the case of a dog whose spinal cord has

been severed. If a painful stimulus is applied to its leg,

the dog shows no signs of distress, but its leg auto-

matically withdraws. Occasionally the same thing

happens in humans if they have broken their neck

or spine. If prodded in the leg they will deny feeling

anything, although their leg pulls back. The isolated

spinal cord can even be taught to make responses

by training it with stimuli that would be painful for a

person with no such injury, but which are not felt at all

by the paralysed person.

So, does the spinal cord feel the pain? This is not a

daft question. The idea of conscious spinal cords may

seem silly, but if you reject this idea then you must

also reject the idea that simple animals who have

only the equivalent of spinal cords (and no human-

like brain) can feel pain. There are also problems

with the role of pain in learning. Is the actual feeling

of pain, or a pain quale, a necessary component of

avoidance learning? If you say ‘no’, you are led to

epiphenomenalism and the possibility of pain-free

zombies who learn without experiencing the pain. If

you say ‘yes’, then in a simple or damaged organism

surely the isolated spinal cord does feel pain, even

if it is not like pain in a much more complex whole

organism.

Euan Macphail (1998) is among those who deny

that other animals can feel pleasure and pain, even

though they can learn. Antonio Damasio argues that

a self is needed for feeling pain. He argues that neu-

ral patterns are not enough – for pain to be painful,

and to have the emotional qualities it does, you also

have to know that you are feeling it.

PHAntom PHenomenA

After losing an arm or leg, more than 90%

of people experience a vivid ‘phantom limb’

that can last for years or even decades.

there are also reports of phantom breasts,

phantom jaws, and even phantom penises

that have phantom erections. Phantom legs

can be cramped into uncomfortable positions

and hands clenched so hard that the fingers

seem to be cutting into the hand. the pain

can be excruciating and terribly hard to

treat (melzack, 1992; Ramachandran and

Blakeslee, 1998).

the thought of pain in a non-existent limb

is so odd that when silas Weir mitchell

coined the term ‘phantom limb’ in 1871,

after thousands who fought in the Ameri-

can Civil War had had limbs removed from

injury or gangrene, he wrote anonymously

for fear of ridicule. But it was later studied

by merleau-Ponty as a way of delving into the problems

of mind–body-dualism. so where is the pain, and what

causes it? An obvious theory is that damaged nerves in the

stump send signals to the brain which, wrongly, assumes

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4.2

Knowing that you have pain requires something

else that occurs after the neural patterns that

correspond to the substrate of pain – the

nociceptive signals – are displayed in the

appropriate areas of the brain stem, thalamus,

and cerebral cortex and generate an image of

pain, a feeling of pain.

(Damasio, 1999, p. 73)

This next stage is also in the brain. It is ‘the neu-

ral pattern of you knowing, which is just another

name for consciousness’ (p. 73). This means that

the necessary neural correlates for pain are to

have both the activity in the pain system, and the

neural pattern of self – and both are not just cor-

relates, but causes.

Saying that feeling pain depends on knowing

you are in pain allows Damasio to distinguish

between self-willed actions and automatic

reactions, such as removing your hand from

the hotplate before you even felt the pain  – in

this case, there is no pain before the action,

only afterwards once your knowledge catches

up. But Damasio undermines his own argument

by saying that even the first pattern alone

‘generate[s] an image of pain, a feeling of pain’

(Damasio, 1999, p. 73). He claims that the feel-

ing of pain depends on knowing one is in pain,

but at the same time he still relies on the more

traditional assumption that nociceptive signals

alone can be sufficient. Notice also that the neu-

ral patterns are ‘displayed’, and that the ‘feeling

‘the neural pattern of

you knowing, which is

just another name for

consciousness’

(Damasio, 1999, p. 73)