The ethics of research involving animals - Nuffield Council on ...
The ethics of research involving animals - Nuffield Council on ...
The ethics of research involving animals - Nuffield Council on ...
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T h e e t h i c s o f r e s e a r c h i n v o l v i n g a n i m a l s<br />
accurate for primary pain, which can result, for example, from a knife cut or burn, but<br />
inaccurate for chr<strong>on</strong>ic deep-organ pain because there is no mapped representati<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> these<br />
areas in the human brain. 14<br />
4.16 Pain pathways also extend to other areas <str<strong>on</strong>g>of</str<strong>on</strong>g> the cortex, known as the associati<strong>on</strong> cortex, the<br />
great expansi<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> which is unique to humans and certain other primates, such as the great<br />
apes. <str<strong>on</strong>g>The</str<strong>on</strong>g>se areas are virtually n<strong>on</strong>-existent in the brains <str<strong>on</strong>g>of</str<strong>on</strong>g> rodents, where more than 70<br />
percent <str<strong>on</strong>g>of</str<strong>on</strong>g> the cortical structures are resp<strong>on</strong>sible for processing olfactory informati<strong>on</strong> (in<br />
humans, less than <strong>on</strong>e percent <str<strong>on</strong>g>of</str<strong>on</strong>g> cortical structures have this functi<strong>on</strong>). It is significant that<br />
the embeddedness <str<strong>on</strong>g>of</str<strong>on</strong>g> pain processing in the associati<strong>on</strong> cortex in humans c<strong>on</strong>tributes to the<br />
emoti<strong>on</strong>al dimensi<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> pain, which is a characteristic <str<strong>on</strong>g>of</str<strong>on</strong>g> suffering. It is therefore possible to<br />
interpret suffering as a higher-order phenomen<strong>on</strong> in that it relates to the experience <str<strong>on</strong>g>of</str<strong>on</strong>g><br />
chr<strong>on</strong>ic pain in a predominantly negative way. Furthermore, this finding suggests that<br />
<str<strong>on</strong>g>animals</str<strong>on</strong>g> such as mice, which lack similarly developed brain structures, may be very unlikely<br />
to experience suffering resulting from pain in a similar way, although they do suffer pain<br />
itself. <str<strong>on</strong>g>The</str<strong>on</strong>g>refore, evidence about differences in the way in which pain is embedded in the<br />
brains <str<strong>on</strong>g>of</str<strong>on</strong>g> different <str<strong>on</strong>g>animals</str<strong>on</strong>g> supports the view that care is required when ascribing states such<br />
as suffering to mice.<br />
4.17 <str<strong>on</strong>g>The</str<strong>on</strong>g> embeddedness <str<strong>on</strong>g>of</str<strong>on</strong>g> pain processing in the associati<strong>on</strong> cortex also appears to c<strong>on</strong>tribute to<br />
the phenomen<strong>on</strong> that suffering can be extremely variable between, and within, individuals.<br />
Some humans, and possibly also some closely related <str<strong>on</strong>g>animals</str<strong>on</strong>g>, have the ability to feel pain<br />
and suffering when there is no pain stimulus, to be untroubled by pain when there is what<br />
others would objectively describe as pain and even to enjoy pain being inflicted in sexual<br />
c<strong>on</strong>texts. In adults, the fear <str<strong>on</strong>g>of</str<strong>on</strong>g> the dentist can intensify innocuous sensati<strong>on</strong>s, but the belief<br />
that it is a price worth paying in order to avoid far greater suffering can also render the<br />
experience <str<strong>on</strong>g>of</str<strong>on</strong>g> the treatment less significant. <str<strong>on</strong>g>The</str<strong>on</strong>g> latter capacity is not usually found in<br />
children, which may suggest that beings with less developed rati<strong>on</strong>al capacities are not<br />
necessarily suffering less, but more, since they are not in a positi<strong>on</strong> to c<strong>on</strong>ceptualise the pain<br />
as a means to an end.<br />
Subjective and objective elements <str<strong>on</strong>g>of</str<strong>on</strong>g> assessing welfare: a correlative approach<br />
4.18 How, in practice, is it possible to assess whether or not <str<strong>on</strong>g>animals</str<strong>on</strong>g> experience pain, suffering or<br />
distress? And how far can our assessments be free from anthropomorphisms? Below we<br />
c<strong>on</strong>sider four approaches: 15<br />
(i)<br />
evaluati<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> clinical signs;<br />
(ii) study <str<strong>on</strong>g>of</str<strong>on</strong>g> <str<strong>on</strong>g>animals</str<strong>on</strong>g>’ choices;<br />
(iii) familiarity with ethological and ecological data; and<br />
(iv) c<strong>on</strong>siderati<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> physiological and neurological features.<br />
In discussing each approach, we also aim to assess how far the criteria used are likely to be<br />
biased by unjustified ascripti<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> human dispositi<strong>on</strong>s to <str<strong>on</strong>g>animals</str<strong>on</strong>g>, thus analysing further the<br />
feasibility <str<strong>on</strong>g>of</str<strong>on</strong>g> the c<strong>on</strong>cept <str<strong>on</strong>g>of</str<strong>on</strong>g> critical anthropomorphism (see paragraph 4.7).<br />
14 Primary pain is c<strong>on</strong>ducted excepti<strong>on</strong>ally quickly, resulting in rapid withdrawal <str<strong>on</strong>g>of</str<strong>on</strong>g> affected body parts where possible. By<br />
c<strong>on</strong>trast, pain brought about by tissue damage <str<strong>on</strong>g>of</str<strong>on</strong>g> internal organs is usually c<strong>on</strong>ducted more slowly, resulting in chr<strong>on</strong>ic,<br />
intense suffering. However, there are also excepti<strong>on</strong>s to this pattern, since colic causes a very acute pain, and b<strong>on</strong>e<br />
metastases can cause twinges <str<strong>on</strong>g>of</str<strong>on</strong>g> substantial pain.<br />
15 All four approaches come into play when defining good practice for assessing welfare, although specific categories may receive<br />
more attenti<strong>on</strong> than others. Since this chapter addresses the questi<strong>on</strong> <str<strong>on</strong>g>of</str<strong>on</strong>g> how to assess pain, suffering and distress in <str<strong>on</strong>g>animals</str<strong>on</strong>g><br />
from first principles, and since there is c<strong>on</strong>siderable overlap between approaches (i)–(iv), we discuss them under <strong>on</strong>e heading.<br />
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