How does the brain distinguish between reality and fiction — and more importantly, does the brain distinguish between reality and fiction?
These questions served as the jumping off point for a new fMRI study that attempted to identify how the brain responds when exposed to contexts involving real people or fictional characters. The study followed up on a similar study conducted in 2008 entitled: “Meeting George Bush versus meeting Cinderella: the neural response when telling apart what is real from what is fictional in the context of our reality“.
In the present study, researchers evaluated subjects’ brain regions–specifically the anterior medial prefrontal and posterior cingulate cortices (amPFC, PCC)–while they were exposed to contexts involving three groups: (1) family and friends (high relevance), (2) famous people (medium relevance), and (3) fictional characters (low relevance). The working hypothesis was that exposure to contexts with a higher degree of relevance would result in stronger activation of the amPFC and PCC.
In previous studies, the amPFC and PCC were implicated in self-referential thinking and autobiographical memory retrieval. The idea behind the present hypothesis is that information about real people, as opposed to fictional characters, is coded in the brain in such a way that its elicits a self-referential and autobiographical response. The more personally relevant the context is, the stronger the response.
The results were consistent with the hypothesis, showing a gradient pattern of activation in which higher relevance entities were associated with stronger amPFC and PCC responses (as shown in the graphic below). This result also held true for several other brain regions to varying degrees.
In other words, for our brains, reality equals relevance.
This study is interesting because it sparks a new round of questions about personal “relevance.” For example, in a social networking context, how is relevance defined? If you never meet someone face-to-face, but talk to them often, can they still be as “relevant” to you as someone you see and talk to all the time? I foresee a future fMRI study that examines brain regions while subjects communicate online with people they talk to frequently (online) but have never seen.
It would also be interesting to know whether the brain’s reality-fiction differentiation system can be short-circuited. If the brain suffers damage to the amPFC and/or PCC, would one’s ability to determine degrees of personal relevance be handicapped? Is it possible that people who believe themselves to have closer relationships with others than they actually do suffer a deficit in this area?
This might be useful for a bit of pop culture analysis as well, such as someone believing they “know” a person 0n a reality TV show. The very nature of reality TV is set up to elicit this sort of response by supplying personal information about people on the show, which creates a sense of “knowing” them. In light of this study, I’m seeing that tactic as a way of tricking the brain into encoding information for higher relevance than it deserves.
Anna Abraham, & Yves von Cramon (2009). Reality = Relevance? Insights from Spontaneous Modulations of the Brain’s Default Network when Telling Apart Reality from Fiction PLoS ONE
Link to the study on PLoS ONE