Animal Minds: Animal Pain (1)

1. Today's topics

Theory approach to consciousness
Epistemic approach
Biological/evolutionary approach (next week, with focus on octopus)

Focus: Animal pain
Do they have it?
Is it different from human pain?
Why does it matter?

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2. The meaning of "pain"

Patrick Mahomes in pain

Focussed on playing...still in pain?

Nociception--nociceptors are specialized neurons that respond to mechanical, thermal, and chemical injury and transmit signals that travel up the spinal chord to the brain
Pain--conscious, phenomenal, there's a "what it's like" to it
Suffering--more complex emotions, cognitive impact

elementary brain info

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3. Do animals feel pain? The theory approach

We start with a theory of what pain IS -- how to explain the mystery of feeling in naturalistic terms.

Representationalism

explanation for the feeling of conscious pain is that pain represents something (but what?) and the representation is "poised" to influence other representations and behavior

HOT theory

explanation for the feeling conscious pain is representation PLUS metarepresentation (Gennaro's "I-thoughts")

Gennaro: yes, animals can have these I-thoughts
Some HOT theorists (Peter Carruthers): animals can't have HOTS, so they have no conscious pain

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4. Do animals feel pain? the epistemic* approach

"Epistemic" means pertaining to knowledge. We can leave it a mystery what conscious pain IS, but still come to KNOW whether animals have it and how theirs compares to ours.

Direct perception (Andrews, chapter 1.3.4)

You see an animal in pain and you just know they're in pain...does this make sense?

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Reasoning based on neural and behavioral similarities

Sir Isaac Newton: "The causes assigned to natural effects of the same kind must be, as far as possible, the same." (Andrews, p. 86, quoting Michael Tye)

Humans and dogs both exhibit behaviors A, B, C...
In humans pain is the cause A, B, C
Same effects have same causes. THEREFORE,
In dogs pain is the cause of A, B, C

Can you turn it around?

Humans and dogs both have brain states X, Y, Z ...
In humans brain states X, Y, Z cause pain.
Same causes have same effects. THEREFORE,
In dogs brain states X, Y, Z cause pain.

Both together: Like causes like.

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Problem: how should we reason about animals when they have different brains or different behavior?

Like causes like

Different causes different???

If this guy has green slime
for a brain and never exhibits human-typical
pain behavior, could he still have pain?

Multiple realizability

Clocks can be made out of different things and behave differently
Minds can be out of different things

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5. Animals a lot like us

Temple Grandin

Animal science professor, slaughterhouse designer, a person with autism and an author of books about autism

Distress in animals: Is it Fear, Pain, or Physical Distress?

Animals in Translation

Cattle and other herd animals (e.g. sheep)

Nociceptors
Similar pathways
Respond to analgesics and opioids
Have endogenous opioids and opioid receptors
Avoid noxious stimuli
Injury guarding, wound tending
Vocalization
Effects on heart-rate and respiration
Differences in behavior: stoicisim in herd animals, less time recuperating
Differences in brains: much smaller prefrontal cortex

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Temple Grandin's hypothesis: these animals are like ...

Leucotomy patients

Had frontal lobe partially severed, to reduce severe chronic pain
They still feel pain, but say it doesn't bother them as much
They take aspirin but not morphine
They can still feel new pain stimuli
They suffer less than normal people

The argument

Animals may be similar to leucotomy patients because: (a) smaller prefrontal cortex than humans, and (b) less extreme pain behavior
Leucotomy patients don't suffer as much as normal people. THEREFORE,
Animals don't suffer as much as people.

Is this a good argument?

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6. Animals less like us

Virginia Braithwaite, Can Fish Feel Pain? -- Yes (dominant view now)

J. D. Rose, "Can fish really feel pain?" -- No

Vinegar and bee venom injected into lips....

nociceptors (22 in face alone) -- trout dissected
pathways to brain -- dissection, study under microscope, electrical stimulation
elevated heart rate and respiration and reduced hunger
wound tending -- they rub snout on gravel on sides of tank after vinegar/bee venom injection
morphine changes these behaviors
But a very different brain -- no cortex (Rose thinks that matters)