Conflict-dependent dynamic of subthalamic nucleus oscillations during moral decisions.
Although lesional, neuroimaging, and brain stimulation studies have provided an insight into the neural mechanisms of judgement and decision-making, all these works focused on the cerebral cortex, without investigating the role of subcortical structures such as the basal ganglia. Besides being an effective therapeutic tool, deep brain stimulation (DBS) allows local field potential (LFP) recordings through the stimulation electrodes thus providing a physiological "window" on human subcortical structures. In this study we assessed whether subthalamic nucleus LFP oscillations are modulated by processing of moral conflictual, moral nonconflictual, and neutral statements. To do so, in 16 patients with Parkinson's disease (8 men) bilaterally implanted with subthalamic nucleus (STN) electrodes for DBS, we recorded STN LFPs 4 days after surgery during a moral decision task. During the task, recordings from the STN showed changes in LFP oscillations. Whereas the 14--30 Hz band (beta) changed during the movement executed to perform the task, the 5--13 Hz band (low-frequency) changed when subjects evaluated the content of statements. Low-frequency band power increased significantly more during conflictual than during nonconflictual or neutral sentences. We conclude that STN responds specifically to conflictual moral stimuli, and could be involved in conflictual decisions of all kinds, not only those for moral judgment. LFP oscillations provide novel direct evidence that the neural processing of conflictual decision-making spreads beyond the cortex to the basal ganglia and encompasses a specific subcortical conflict-dependent component.
Università degli Studi di Milano, Milan, Italy.
Manuela
M
Fumagalli
Gaia
G
Giannicola
Manuela
M
Rosa
Sara
S
Marceglia
Claudio
C
Lucchiari
Simona
S
Mrakic-Sposta
Domenico
D
Servello
Claudio
C
Pacchetti
Mauro
M
Porta
Marco
M
Sassi
Roberta
R
Zangaglia
Angelo
A
Franzini
Alberto
A
Albanese
Luigi
L
Romito
Sylvie
S
Piacentini
Stefano
S
Zago
Gabriella
G
Pravettoni
Sergio
S
Barbieri
Alberto
A
Priori
D000368:Aged; D001479:Basal Ganglia / Q000502:physiology; D002540:Cerebral Cortex / Q000502:physiology; D003220:Conflict, Psychological; D003657:Decision Making / Q000502:physiology*; D046690:Deep Brain Stimulation; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008959:Models, Neurological; D009014:Morals; D010300:Parkinson Disease / Q000503:physiopathology / Q000523:psychology / Q000628:therapy*; D020531:Subthalamic Nucleus / Q000502:physiology*