TY - JOUR
T1 - Unraveling the role of the hippocampus in reversal learning
AU - Vilà-Balló, Adrià
AU - Mas-Herrero, Ernest
AU - Ripollés, Pablo
AU - Simó, Marta
AU - Miró, Júlia
AU - Cucurell, David
AU - López-Barroso, Diana
AU - Juncadella, Montserrat
AU - Marco-Pallarés, Josep
AU - Falip, Mercè
AU - Rodríguez-Fornells, Antoni
N1 - Publisher Copyright:
© 2017 the authors.
PY - 2017
Y1 - 2017
N2 - Research in reversal learning has mainly focused on the functional role of dopamine and striatal structures in driving behavior on the basis of classic reinforcement learning mechanisms. However, recent evidence indicates that, beyond classic reinforcement learning adaptations, individuals may also learn the inherent task structure and anticipate the occurrence of reversals. A candidate structure to support such task representation is the hippocampus, which might create a flexible representation of the environment that can be adaptively applied to goal-directed behavior. To investigate the functional role of the hippocampus in the implementation of anticipatory strategies in reversal learning, we first studied, in 20 healthy individuals (11 women), whether the gray matter anatomy and volume of the hippocampus were related to anticipatory strategies in a reversal learning task. Second, we tested 20 refractory temporal lobe epileptic patients (11 women) with unilateral hippocampal sclerosis, who served as a hippocampal lesion model. Our results indicate that healthy participants were able to learn the task structure and use it to guide their behavior and optimize their performance. Participants' ability to adopt anticipatory strategies correlated with the gray matter volume of the hippocampus. In contrast, hippocampal patients were unable to grasp the higher-order structure of the task with the same success than controls. Present results indicate that the hippocampus is necessary to respond in an appropriately flexible manner to high-order environments, and disruptions in this structure can render behavior habitual and inflexible.
SIGNIFICANCE STATEMENT Understanding the neural substrates involved in reversal learning has provoked a great deal of interest in the last years. Studies with nonhuman primates have shown that, through repetition, individuals are able to anticipate the occurrence of reversals and, thus, adjust their behavior accordingly. The present investigation is devoted to know the role of the hippocampus in such strategies. Importantly, our findings evidence that the hippocampus is necessary to anticipate the occurrence of reversals, and disruptions in this structure can render behavior habitual and inflexible.
AB - Research in reversal learning has mainly focused on the functional role of dopamine and striatal structures in driving behavior on the basis of classic reinforcement learning mechanisms. However, recent evidence indicates that, beyond classic reinforcement learning adaptations, individuals may also learn the inherent task structure and anticipate the occurrence of reversals. A candidate structure to support such task representation is the hippocampus, which might create a flexible representation of the environment that can be adaptively applied to goal-directed behavior. To investigate the functional role of the hippocampus in the implementation of anticipatory strategies in reversal learning, we first studied, in 20 healthy individuals (11 women), whether the gray matter anatomy and volume of the hippocampus were related to anticipatory strategies in a reversal learning task. Second, we tested 20 refractory temporal lobe epileptic patients (11 women) with unilateral hippocampal sclerosis, who served as a hippocampal lesion model. Our results indicate that healthy participants were able to learn the task structure and use it to guide their behavior and optimize their performance. Participants' ability to adopt anticipatory strategies correlated with the gray matter volume of the hippocampus. In contrast, hippocampal patients were unable to grasp the higher-order structure of the task with the same success than controls. Present results indicate that the hippocampus is necessary to respond in an appropriately flexible manner to high-order environments, and disruptions in this structure can render behavior habitual and inflexible.
SIGNIFICANCE STATEMENT Understanding the neural substrates involved in reversal learning has provoked a great deal of interest in the last years. Studies with nonhuman primates have shown that, through repetition, individuals are able to anticipate the occurrence of reversals and, thus, adjust their behavior accordingly. The present investigation is devoted to know the role of the hippocampus in such strategies. Importantly, our findings evidence that the hippocampus is necessary to anticipate the occurrence of reversals, and disruptions in this structure can render behavior habitual and inflexible.
KW - Epilepsy
KW - Flexible behavior
KW - Hippocampus
KW - Model-based strategies
KW - Reinforcement learning
KW - Reversal learning
KW - Nerve Net/anatomy & histology
KW - Reversal Learning/physiology
KW - Gray Matter/anatomy & histology
KW - Humans
KW - Middle Aged
KW - Male
KW - Epilepsy/pathology
KW - Hippocampus/anatomy & histology
KW - Adult
KW - Female
KW - Models, Neurological
KW - Anticipation, Psychological/physiology
KW - Discrimination Learning/physiology
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UR - http://www.scopus.com/inward/citedby.url?scp=85024095592&partnerID=8YFLogxK
U2 - 10.1523/JNEUROSCI.3212-16.2017
DO - 10.1523/JNEUROSCI.3212-16.2017
M3 - Article
C2 - 28592695
AN - SCOPUS:85024095592
SN - 0270-6474
VL - 37
SP - 6686
EP - 6697
JO - Journal of Neuroscience
JF - Journal of Neuroscience
IS - 28
ER -