Cognition and behavior: Brain scans probe joint attention
Using functional magnetic resonance imaging (fMRI), researchers have for the first time identified brain regions activated by joint attention, the process in which two people direct their attention to the same object, person or topic of conversation. The findings appeared 16 April in Human Brain Mapping1.
Joint attention skills emerge in the first two years of life. Children with autism tend to have trouble both initiating and responding to interactions involving joint attention.
Most studies investigating the neural underpinnings of joint attention have looked at how individuals with autism respond to other people’s eye movements2. The new study is the first to measure brain activity during real-time social interactions between an individual with autism and another person.
In the new study, 13 high-functioning adults with autism spectrum disorder and two sets of typical controls played a game with the experimenter called ‘Catch the Mouse.’ In this game, the experimenter and the participant simultaneously watch a cartoon mouse move between cheese houses in the four corners of the screen. Sometimes the participant sees a clue — a tail peeking out — of where to look for the mouse, and at others, the experimenter sees the clue. The mouse does not fully appear until both parties are looking at the correct corner.
In both the autism and control groups, when the participant initiates the joint attention — that is, when the participant sees the clue, rather than the experimenter — it takes longer for the pair to find the correct mouse location, the study found. The duration and direction of gaze in the autism and control groups are also similar.
The brain activation patterns vary, however. But only when the experimenter initiates joint attention.
Surprisingly, when participants initiate the joint attention, there is little difference in brain activation patterns between autism and control groups, the study found. The researchers speculate that this may be because the participants are focused on a game with explicit instructions and a concrete goal, rather than “sharing for sharing’s sake.” They suggest that researchers should attempt to assess more spontaneous social interactions.
1: Redcay E. et al. Hum. Brain Mapp. Epub ahead of print (2012) PubMed
2: Pitskel N.B. et al. J. Autism Dev. Disord. 41, 1686-1693 (2011) PubMed