Little Albert – one of the most famous research participants in psychology’s history – but who was he?

For decades, the true identity and subsequent fate of this poor infant nicknamed "Little Albert" has remained a mystery.But recently this has changed, thanks to the tireless detective work of two independent groups of scholars. Now there are competing proposals for who Little Albert was and what became of him. Which group is correct – the one led by Hall Beck at Appalachian State University in North Carolina, or the other led by Russell Powell at MacEwan University in Alberta?

These developments are so new they have yet to be fully documented in any textbooks. Fortunately, Richard Griggs at the University of Florida has written an accessible outline of the evidence unearthed by each group. His overview will be published in the journal Teaching of Psychology in January 2015, but the Research Digest has been granted an early view.

The starting point for both groups of academics-cum-detectives was that Little Albert is known to have been the son of a wet nurse at Johns Hopkins. Hall Beck and his colleagues identified three wet nurses on the campus in that era, and they found that just one of them had a child at the right time to have been Little Albert. This was Arvilla Merritte, who named her son Douglas. Further supporting their case, Beck's group found a portrait of Douglas and their analysis suggested he looked similar to the photographs and video of Little Albert and could well be the same child.

The Merritte line of enquiry was further supported, although controversially so, when a clinical psychologist Alan Fridlund and his colleagues analysed footage of Little Albert and deemed that he was neurologically impaired. If true, this would fit with the finding that Douglas Merritte's medical records show he had hydrocephalus ("water on the brain"). Of course this would also mean that the Little Albert study was even more unethical than previously realised.

Perhaps the most glaring short-coming of the Merritte theory is why the original researchers John Watson and Rosalie Rayner called the baby Albert if his true name was Douglas Merritte. Enter the rival detective camp headed by Russell Powell. Their searches revealed that in fact another of the John Hopkins' wet nurses had given birth to a son at the right time to have been Little Albert. This child was William A. Barger, although he was recorded in his medical file as Albert Barger. Of course, this fits the nickname Little Albert (and in fact, in their writings, Watson and Rayner referred to the child as "Albert B").

Also supporting the William Barger story, Powell and his team found notes on Barger's weight which closely match the weight of Little Albert as reported by Watson and Rayner. This is also ties in with the fact that Little Albert looks healthily chubby in the videos (Merritte, by contrast, was much lighter). Meanwhile, other experts have criticised the idea of diagnosing Little Albert as neurologically impaired based on a few brief video clips, further tilting the picture in favour of the Barger interpretation. Indeed, summing the evidence for each side, Griggs decides in favour of Powell's camp. "Applying Occam's razor to this situation would indicate that Albert Barger is far more likely to have been Little Albert," he writes.

What do the two accounts mean for the fate of Little Albert? If he was Douglas Merritte, then the story is a sad one – the boy died at age six of hydrocephalus. In contrast, if Little Albert was Willam Barger, he in fact lived a long life, dying in 2007 at the age of 87. His niece recalls that he had a mild dislike of animals. Was this due to his stint as an infant research participant? We'll probably never know.