A touch of pleasure receives more than a touch of careful study in this report, which the researchers perhaps did prepare with a touch of pleasure:
“Vicarious responses to social touch in posterior insular cortex are tuned to pleasant caressing speeds,” India Morrison, Malin Björnsdotter and Håkan Olausson, Journal of Neuroscience, vol. 31, no. 26, 2011, pp. 9554-9562. The authors are at Sahlgrenska University Hospital, Gothenburg, Sweden and the University of Gothenburg.
BONUS: Citing that study, one researcher pursued the pleasure question to greater depth, as is evident even in the title of his report:
“Doing it… wild? On the role of the cerebral cortex in human sexual activity,” Janniko R Georgiadis, Socioaffective Neuroscience and Psychology, vol. 2, 2012. The author is at the University of Groningen, a place noted for its pursuit of sexual knowledge.