There are also a considerable amount of ethical and philosophical arguments for and against the use of non-human animals in psychological research. The first issue commonly raised is that of the suffering that animals are commonly subjected to in psychological research. A commonly-cited example of this is Calhoun's rats study in which the rats reproduced rapidly so that the researcher could see the effects of overcrowding. It may be considered arrogant to believe that humans can subject animals to suffering if such suffering would be considered unethical if humans were subjected to it; this is the argument from those who note that animals' physical similarities may lead them to feel pain in the same way that humans do.
A cost-benefit analysis may be carried out prior to conducting research involving animals. One method of doing this is Bateson's decision cube, which takes into account three dimensions before saying whether or not the research should go ahead: the quality of the research, the certainty of benefit, and the amount of animal suffering involved. This is advantageous as it allows researchers to consider several criteria before carrying out their research, preventing research from going ahead just because the certainty of benefit is high (even if animal suffering is very high as well). However, it is often criticised for being too simplistic: it is impossible to quantify the amount of suffering an animal will receive, for example. It is also hard to assess the quality of research before the research has actually been carried out. This means that Bateson's decision cube may not be a reliable method of assessing the ethics of carrying out a study.
There may be times when animal suffering can be justified. For example, if the research is going to produce significant benefits for humans, or even for the type of animals used in the study. An example of this is in stress research, where animals may be subjected to high levels of stress or given treatments to test if they will reduce stress levels. Should such findings be successful, the benefits would be large in terms of reducing stress in patients. This justification is debateable, however, on the grounds that it may be a 'speciesist' stance to say that the suffering of animals can be justified by benefits for humans. However, evolutionists may argue that humans are on the top of the phylogenetic tree, and therefore are obliged to use lower animals in testing if such research would be for the greater benefit of mankind.
Psychological research on animals is often justified by those who argue that animals do not have the same feelings as humans. Indeed, Sneddon et al. (2003) found that fish do not feel pain. Additionally, a traditional view is that humans and non-humans can be differentiated by the fact that non-humans do not have a soul and therefore can not have real feelings or emotions. This would imply that it is not unethical to subject animals to harsh conditions in research if it is for the good of humans, as there would be no true suffering involved. However, this viewpoint may fall back on itself, in that if it is true that animals cannot have the same minds as humans, the findings of any psychological research carried out on them would not extrapolate.
Modern psychological research, at least in the UK and USA, accounts for the modern views of issues such as animal rights. All research must abide by the British Psychological Society (BPS) guidelines, which outline what is acceptable in the treatment of animals; and the research must also be within the law. Recently, less invasive methods of investigation using animals have been developed and being used in research, which minimises animal suffering and allows for a moral justification for animal research. These still do not take into account the strictest notion of animal rights; that is, that they have the same (or similar) rights as humans. This would include the right not to participate in research, or to withdraw at any time during the research or retrospectively. As this is impossible for animals to do, it could be argued that psychological research using animals is unethical in itself. There are other modern approaches that could be used as alternatives to animal research, such as brain scans and computer modelling of cognitive processes.
In conclusion, the ethics of using animals in psychological research is debateable, but certain uses of them may be considered more acceptable than others. Scientifically, their use for studying animal behaviour of course carries advantages, but extrapolation of their behaviour to explain human behaviour may not be suitable; or more suitable with some animals than with others. Nonetheless, animal psychological research, although still commonplace, is becoming less frequent and less invasive, in favour of alternative methods of research.
