Decision Makers May Be Blind To The Outcome Of Their Choice

Theauthors on this paper are Petter Johansson, a graduate student; LarsHall, a researcher; Sverker Sikström, an assistant professor; all fromLund University Cognitive Science; and Andreas Olsson, a graduatestudent in NYU's Department of Psychology.

Researchers showedpicture-pairs of female faces to the participants and asked them tochoose which face in each pair they found most attractive. In addition,immediately after their choice, they were asked to verbally describethe reasons for choosing the way they did. Unknown to the participants,on certain trials, a card magic trick was used to secretly exchange oneface for the other. Thus, on these trials, the outcome of the choicebecame the opposite of what they intended.

The researchersmeasured whether the participants noticed that something went wrongwith their choice, both concurrently, during the experimental task, andretrospectively through a post-experimental interview. Less than 10% ofall manipulations were detected immediately by the participants, andcounting all forms of detection no more than a fifth of all manipulatedtrials were exposed. The researchers call this effect choice blindness.

Theoriesabout decision-making generally assume that we recognize when ourintentions and the outcome of our choices do not match up, but thisstudy shows that this assumption is not necessarily correct. Byshedding new light on the links between intentions and outcomes, theseresults challenges both current theories of decision making, and commonsense notions of choice and self-knowledge.

The researchers alsosought to understand if the verbal reports given by the participantsdiffered between the faces that they actually chose, and the ones thatthey ended up with in a manipulated trial. "Based on common sense aloneone might suspect that the reports given for normal trials and for themanipulated trials would differ in many ways", said Hall. "After all,revealing the reasons behind a choice is something we very often do ineveryday life. But revealing the reasons behind a choice we did notmake is a very strange thing indeed."

However, using a variety ofmeasures, the researchers found that the two types of reports wereremarkably similar. ''When asked to motivate their choices, theparticipants delivered their verbal reports with the same confidence,and with the same level of detail and emotionality for the faces thatthat were not chosen, as for the ones that were actually chosen''Johansson said.

Despite the intimate familiarity we have witheveryday decision making, it is very difficult to determine what we canknow about this process from the 'inside', by reflection andintrospection. A great barrier for scientific research in this domainis the nature of subjectivity. How can researchers ever verify thereports of the participants involved, when they have no means ofchallenging them? But by using choice blindness as an instrument, theresearchers were able to 'get between' the decisions of theparticipants and the outcomes they were presented with. "Our experimentintroduces an entirely novel methodology that can be used toinvestigate choice and introspection'' Hall said. ''This may lead to animproved understanding of the processes behind both truthful andconfabulatory reports''