Wednesday, 12 October 2011
That's according to an international team of psychologists who say the devices allow for experimentation on an unprecedented scale. "The use of smartphones allows us to dramatically increase the amount of data collected without sacrificing precision," say Stephane Dufau and his colleagues, "and thus has the potential to uncover laws of mind that have previously been hidden in the noise of small-scale experiments." In contrast, they argue that conducting cognitive psychology experiments over the internet has not been a great success because of problems obtaining the necessary precision of timing.
To illustrate their point, the researchers developed an iPhone/iPad App that replicates the classic "lexical decision task" used by psychologists to study the sub-second mental processes involved in reading. Participants are presented with a series of letter strings and simply have to indicate as quickly as possible whether each one is a real word or not. The App was launched as a seven-language international effort in December 2010 and after just four months data had been collected from over four thousand participants. By way of comparison, it took more than three years to collect a similar amount of data via conventional means. It will be easy to add further languages to the App, including non-Romanic alphabet languages like Chinese.
The free Science XL App presents the task to users as a test of word power and offers a choice of task lengths from two to six minutes. Once enrolled, participants use Yes/No buttons on the touch-screen display to indicate whether the letter strings that appear are real words or not. Each participant's performance stats are presented at the end and they are given the option of forwarding their results to the researchers via email. Extreme negative outliers were excluded from further analysis. There is the obvious issue of participants choosing to only send in favourable performance data. However, this doesn't spoil the ability to examine the effect of different factors on performance. For example, the data collected via the App matched many known features of lexical decision time data: reaction times were quicker for more common words and mean reaction times correlated with data collected in psychology labs.
Using smartphones "has wide multidisciplinary applications in areas as diverse as economics, social and affective neuroscience, linguistics, and experimental philosophy," say Dufau and his collaborators. "Finally it becomes possible to reliably collect culturally diverse data on a vast scale, permitting direct tests of the universality of cognitive theories."
This isn't the first time that psychology researchers have aired their excitement about the potential of mobile technologies to revolutionise their methods. A 2009 study used mobile phones to monitor participants' social movements and phone calls.
Dufau, S., Duñabeitia, J., Moret-Tatay, C., McGonigal, A., Peeters, D., Alario, F., Balota, D., Brysbaert, M., Carreiras, M., Ferrand, L., Ktori, M., Perea, M., Rastle, K., Sasburg, O., Yap, M., Ziegler, J., and Grainger, J. (2011). Smart Phone, Smart Science: How the Use of Smartphones Can Revolutionize Research in Cognitive Science. PLoS ONE, 6 (9) DOI: 10.1371/journal.pone.0024974
-Thanks to Marc Brysbaert for the tip-off.
Post written by Christian Jarrett for the BPS Research Digest.