#mogil

My entire world. by dedecs featuring strappy bikinis ❤ liked on Polyvore

Untitled #1211 by florabias featuring short dresses

by Rebecca Steinberg

Nearly all studies using animal models can be impacted by an animal’s stress level. Jeffrey Mogil’s group at McGill University noticed an extraordinary connection between the gender of an experimenter and how it confounded with their study on pain measurement.

Mice showed fewer signs of physical pain when in the presence of male researchers when measuring the intensity of their grimace. This observation is not merely based on the sight of a male, but is even offset by the odor of the experimenter. Mogil, et al. placed male and female odor-ridden T-shirts within the lab room and found a similar effect.

This decrease in pain was not merely a masking of pain, but an actual physical decrease in pain, according to Mogil’s group. This was measured by the amount of stress hormone released, the amount of fecal matter deposited, and the animal’s body temperature, among other methods. Mogil believes that this natural painkiller is part of a primordial response, established for eons. It may be an instinctive attempt to not appear weak in front of a threatening presence.

Stress levels are critical to the establishment of animal behavior. In a stressful environment, any recorded responses may differ vastly from responses in a relaxed state of mind. This may be a cause for the inability for certain labs to replicate studies (Grimm, D). There may even be human applications for this information, in comparing the pain responses to treatment by a male or female physician.

Future studies should take this confounder into consideration. The findings by Mogil, et al. serve as an eye-opening reminder of the many detailed factors that can make or break the results of an experiment.

  References:

  Grimm, D. (2014). Male Scent May Compromise Biomedical Research. Science/AAAS 3 May 2014. < http://news.sciencemag.org/brain-behavior/2014/04/male-scent-may-compromise-biomedical-research>.

  Sorge, RE, Loren, JM, Isbester, KA, Sotocinal, SG, Rosen, S, Tuttle, AB, Wieskopf, JS, Acland, EL, Dokova, A, Kadoura, B, Leger, P, Mapplebeck, JCS, McPhail, M, Delaney, A, Wigerblad, G, Schumann, AP, Quinn, T, Frasnelli, J, Svensson, CI, Sternberg, WF, Mogil, JS. (2014)  Olfactory exposure to males, including men, causes stress and related analgesia in rodents. Nat Meth 2014/04/28 online. http://www.nature.com/nmeth/journal/vaop/ncurrent/full/nmeth.2935.html.