Thursday, February 7, 2013

Parental care of rodents is not the same as socioeconomic status in humans.

The question of socioeconomic status in scientific research is an interesting one. Many experiments do not take socioeconomic status into account, yet studies show that socioeconomic status can significantly alter the human brain. The article, “Socioeconomic status and the brain: mechanistic insights from human and animal research” addresses some of these issues. However, one of the main problems I noticed with this article is the equivalence of socioeconomic status with quality of parental care. The article seems to associate lower socioeconomic status with parental neglect. Conversely, higher socioeconomic status is associated with higher quality parental care. While there may in fact be a correlation, status is by no means a perfect predictor of parental quality.

Parental care in rats (source)

One of the studies cited in the article uses lack of grooming in rats as a model for low socioeconomic status based on the idea that parental care is equated to status. However, this model shows no more than the effects of early life stress and parental neglect. It would not be appropriate to extend this to make conclusions about socioeconomic status. For one thing, rats do not have a social hierarchy, and without the concept of social status one should not draw conclusions.

Even primates with clearly defined social hierarchies do not innately have a concept of economy. It would be interesting to extend this study into nonhuman primates, but it would be necessary to introduce the concept of money into the system. A similar construct has been demonstrated by Keith Chen and Laurie Santos of Yale University. These researchers trained a group of capuchin monkeys to use money as a means of exchange. Aside from observing the first nonhuman prostitute, they showed that species other than humans can be taught the concept of money. If one were to combine this technique with a species that has a well defined, complex social hierarchy, say the Rhesus macaque, then you would truly have an animal model of socioeconomic status. Basically, rats aren’t cutting it.

--Michael McKinnon

Want to cite this post?

McKinnon, M. (2012). Parental care of rodents is not the same as socioeconomic status in humans. The Neuroethics Blog. Retrieved on , from


Martha J. Farah said...

Whoa, slow down there, Michael. If you are going to call for greater conceptual clarity in distinguishing among fuzzy and evolving concepts such as socioeconomic status and quality of parenting, then you should be as clear as possible with your own facts and arguments!

First, my co-authors and I did not write that low SES and poor parenting are the same thing. Rather, we cited strong empirical evidence of a correlation between SES and certain parenting behaviors that affect child development, and we explained the correlation in terms of the generally higher levels of stress on parents of lower SES. We also pointed out that this is one among many mechanisms reviewed in our article whereby childhood SES could impact brain development.

Second, the idea that an animal model would need to involve money or an economy to be relevant to SES is not correct. The first S in SES encompasses many potent causal factors, which contribute to the differences we observe in mental and physical health between rich and poor. Social and economic factors are tightly intertwined in human society. Nevertheless, or perhaps especially because of this, animals can provide valid models for testing hypotheses about specific social factors.

I wanted to respond here because other readers may get the wrong idea about this very sensitive subject. The biology of social inequality can easily be misunderstood as fatalistic or blaming the victim. So let’s all try to be especially clear in our writing on this subject.

Samuel josuah said...

Yeah! I go with Farah. Environmental enrichment, parental care and such external (socioeconomic) factors in mice/rats, though cannot be exactly extrapolated to human settings, such models would definitely be valuable tools in the SES research.