Motivations for Science

Where do cognitive scientists get subjects for their studies?

There is a certain amount of variation, but the workhorse of cognitive science is the Psych 100 student. At many universities, introductory psychology students are required to participate in studies (though I believe there is often an option for people who strongly object).

This is billed as an educational experience, and more or less effort is put into making it educational (I've been very impressed with both Harvard and MIT on this point), but it is also part of the machinery that makes the science possible.

The other option typically is to pay participants. Currently, the going rate at Harvard is $10/hour. This is supposed to be compensation for time, travel, etc., but certainly lots of undergraduates who are not currently enrolled in a psych class use it to generate pocket cash.

Conflicting Goals

One potential drawback of this system is that the motivations of the participants and of the researchers are not always aligned. The researcher typically wants to get good data; the participant may just want their $10 or course credit.

The truth is the vast majority of participants give the experiment a good faith effort, but there are always some (I'd say about 5-10%, in my experience) who just answer randomly and quickly in order to get out as soon as possible.

There are ways to help realign the participants' and researchers' interests. One is to the program the experiment such that if you get all the answers right, you finish sooner than if you guess randomly. That makes guessing a bit less tempting a strategy. (An easy way of doing this in a computerized experiment is to have the computer respond with a long error message every time a question is answered incorrectly, with the effect that participants who make many errors take longer to finish.)

What Motivations do Parents Have?

Prior to working in a developmental lab, I wondered what motivations parents have for bringing in their children for developmental studies. It takes them more time, since unlike our "adult" subjects, they typically do not live on campus, and they get compensated less (we give our participants a cheap toy plus $5 for gas -- and $5 means a lot less to a parent than a college student).

I had heard it rumored that many are hoping the "affiliation" with Harvard will help their kids in the future or that they are very interested in having a scientist study their kid and discover what a genius the kid is. This frankly made me a bit uncomfortable.

Now I've actually interacted with a lot of parents and kids, and if those are their motivations, I don't see it. The main motivation seems to be that the kids really enjoy coming to the lab. We have a big bin full of toys, and we usually play with them for a while when they first come in. And then, the experiments are tailored such that kids really find them entertaining. Finally, many seem to really enjoy collecting the stuffed animals we give them as prizes at the end.

Parents are always looking for ways to keep their children entertained. It never occurred to me that taking the kids to a developmental lab would be one of those ways, but it appears that it is.

(Some parents are also definitely motivated by participating in science. At the end of the experiment, I always describe the experiment to them. Some are clearly not overly interested, but others may stay an extra 10-15 minutes to talk about the study.)