TY - JOUR
T1 - Transcranial direct current stimulation over the left prefrontal cortex increases randomness of choice in instrumental learning
AU - Turi, Zsolt
AU - Mittner, Matthias
AU - Opitz, Alexander
AU - Popkes, Miriam
AU - Paulus, Walter
AU - Antal, Andrea
N1 - Publisher Copyright:
© 2014 Elsevier Ltd.
PY - 2015/2/1
Y1 - 2015/2/1
N2 - Introduction: There is growing evidence from neuro-computational studies that instrumental learning involves the dynamic interaction of a computationally rigid, low-level striatal and a more flexible, high-level prefrontal component. Methods: To evaluate the role of the prefrontal cortex in instrumental learning, we applied anodal transcranial direct current stimulation (tDCS) optimized for the left dorsolateral prefrontal cortex, by using realistic MR-derived finite element model-based electric field simulations. In a study with a double-blind, sham-controlled, repeated-measures design, sixteen male participants performed a probabilistic learning task while receiving anodal and sham tDCS in a counterbalanced order. Results: Compared to sham tDCS, anodal tDCS significantly increased the amount of maladaptive shifting behavior after optimal outcomes during learning when reward probabilities were highly dissociable. Derived parameters of the Q-learning computational model further revealed a significantly increased model parameter that was sensitive to random action selection in the anodal compared to the sham tDCS session, whereas the learning rate parameter was not influenced significantly by tDCS. Conclusion: These results congruently indicate that prefrontal tDCS during instrumental learning increased randomness of choice, possibly reflecting the influence of the cognitive prefrontal component.
AB - Introduction: There is growing evidence from neuro-computational studies that instrumental learning involves the dynamic interaction of a computationally rigid, low-level striatal and a more flexible, high-level prefrontal component. Methods: To evaluate the role of the prefrontal cortex in instrumental learning, we applied anodal transcranial direct current stimulation (tDCS) optimized for the left dorsolateral prefrontal cortex, by using realistic MR-derived finite element model-based electric field simulations. In a study with a double-blind, sham-controlled, repeated-measures design, sixteen male participants performed a probabilistic learning task while receiving anodal and sham tDCS in a counterbalanced order. Results: Compared to sham tDCS, anodal tDCS significantly increased the amount of maladaptive shifting behavior after optimal outcomes during learning when reward probabilities were highly dissociable. Derived parameters of the Q-learning computational model further revealed a significantly increased model parameter that was sensitive to random action selection in the anodal compared to the sham tDCS session, whereas the learning rate parameter was not influenced significantly by tDCS. Conclusion: These results congruently indicate that prefrontal tDCS during instrumental learning increased randomness of choice, possibly reflecting the influence of the cognitive prefrontal component.
KW - Dorsolateral prefrontal cortex
KW - Exploitation
KW - Exploration
KW - Probabilistic learning task
KW - Transcranial direct current stimulation
KW - Working memory
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U2 - 10.1016/j.cortex.2014.08.026
DO - 10.1016/j.cortex.2014.08.026
M3 - Article
C2 - 25282053
AN - SCOPUS:84907710763
SN - 0010-9452
VL - 63
SP - 145
EP - 154
JO - Cortex
JF - Cortex
ER -