Final Report Summary - DA AND DECISIONS (The role of dopamine and novelty in decision-making in humans: behavioral and neuroimaging studies)
Using fMRI, we showed for the first time that neural responses to rewarding stimuli in the striatum were enhanced in the context of novelty. Using MEG we discovered that neural correlates of reward anticipation emerge as a modulation of oscillatory activity over frontal sensors within 150 ms. Finally, contextual novelty enhanced the effects of reward anticipation on oscillatory activity.
In a series of behavioural experiments we could show that after conditioning abstract stimuli to monetary wins or losses, the incidental presentation of these stimuli as contextual cues in an independent gamble task biased the participants’ decisions to choose between a gamble and a sure option. This contextual bias is analogous to the framing effect described in prospect theory of decision making, and suggests that the framing effect could be explained as arising from an influence of conditioned associations on goal directed decision making. Moreover, we conducted an fMRI study using the same task and found that activation of the amygdala was the brain correlate of the observed bias as has been described in previous fMRI experiments of the classical framing effect.
In a series of behavioural experiments we could show that after conditioning abstract stimuli to monetary wins or losses, the incidental presentation of these stimuli as contextual cues in an independent gamble task biased the participants’ decisions to choose between a gamble and a sure option. This contextual bias is analogous to the framing effect described in prospect theory of decision making, and suggests that the framing effect could be explained as arising from an influence of conditioned associations on goal directed decision making. Moreover, we conducted an fMRI study using the same task and found that activation of the amygdala was the brain correlate of the observed bias as has been described in previous fMRI experiments of the classical framing effect.
