How do I find research groups that do work in field X?
Well, I find reasonable numbers for research groups focusing on eyetracking by using Google and search operators. Of course, you should add some redundant similar terms (eye-movement, baby,...)

Notice, there are some patterns:


american universities nearly always have edu (actually it's even a domain) in their URL, german univ. uni. So using inurl:edu in google filters out a lot. Non-university institutes like german Max-Planck often have URL patterns too. 
further add  -filetype:pdf -filetype:doc -filetype:ppt -filetype:ps to filter out more useless results
add 2010..2012 to be sure the site/group is still active and the topic on their agenda.
add research | forschung (latter being german translation, but afaik nowadays most natural sciences groups in Germany have a english (&amp; german) page)


Some research branches also have a online directory, there exist also internet directories like dmoz (not sure if this stuff is up to date, probably some dead links):

http://www.eurosys.org/directory/  

http://www.dmoz.org/Science/Biology/Neurobiology/Research_Groups_and_Centers/   

http://www.ida.liu.se/ext/etai/actions/colloq/groups.html   

At least I can say that most research groups in Germany will have a english home page and short summary/research topics/open positions on it. So there should be no general problem to find them by some "serious" googling. But don't use too specific keywords, "eyetracking on infants", "dualistic view" is too special imho, use keywords being specific rather to the topic than the exact methodology. They are probably mainly interested in how the visual recognition system adapts and learns over time, this is the bigger thematic picture. You attract master and phd students not by naming a special experimental method, so you will not find these type of keywords often on a group page, where they often try to put in a minimum of time.