Proefschrift_Holstein

Reward modulation of cognitive function: the nucleus accumbens

performance in the low reward condition, in combination with marginally impaired task- switching performance in the high reward context in animals without an intact AcbC. Importantly, lesions of the AcbC did not impair flexible control per se (i.e. lesions did not affect accuracy on the task-switching paradigm). This finding fits remarkably well with previous studies, although none assessed directly whether manipulating the amount of reward earned when executing an appropriate action alters cognitive control. Classical learning paradigms

High Low Reward

6

4

2

0

-2

Switch cost (repeat - switch) in terms of accuracy (correct > incorrect)

-4

improved performance (lower switch cost)

-6

pre

post

pre

post

Surgery

Surgery

Sham

Lesion

Group

Figure 6.4 | Performance (accuracy) in terms of switch cost (repeat – switch) We observed no effect of sham surgery on overall or rewarded task-switching performance, while an effect of surgery on rewarded task-switching performance was observed in the group with lesions of the accumbens core, without affecting overall accuracy. Error bars represent standard errors of the difference.

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