of interest? (AS)

[Leo Caves <***>]

I thought that this article (see below) on "neuroeconomics" might be of 
interest to the list - it provides evidence (via MRI) of brain activity 
that is interpreted as internal model building in the development of 
trust in a simple economic exchange game.

There is a short but very interesting interview with one of the authors 
on a BBC Science radio programme "Leading Edge" on 31 Mar 2005 that can 
be accessed at:
http://www.bbc.co.uk/radio4/science/leadingedge.shtml
(Click on the "Listen Again" link - requires RealOne player, interview 
starts at around 3:15 minutes or so; this link is will only be active 
for the following week - after that the programme should be accessible 
from the archives)

--Leo

Full article at:  
http://www.sciencemag.org/cgi/content/short/308/5718/78
Title and abstract below:
Getting to Know You: Reputation and Trust in a Two-Person Economic 
Exchange
 Brooks King-Casas,1 Damon Tomlin,1 Cedric Anen,3 Colin F. Camerer,3 
Steven R. Quartz,3 P. Read Montague1,2*

 Using a multiround version of an economic exchange (trust game), we 
report that reciprocity expressed by one player strongly predicts 
future trust expressed by their partner—a behavioral finding mirrored 
by neural responses in the dorsal striatum. Here, analyses within and 
between brains revealed two signals—one encoded by response magnitude, 
and the other by response timing. Response magnitude correlated with 
the "intention to trust" on the next play of the game, and the peak of 
these "intention to trust" responses shifted its time of occurrence by 
14 seconds as player reputations developed. This temporal transfer 
resembles a similar shift of reward prediction errors common to 
reinforcement learning models, but in the context of a social exchange. 
These data extend previous model-based functional magnetic resonance 
imaging studies into the social domain and broaden our view of the 
spectrum of functions implemented by the dorsal striatum.