Reward-Based Decision-Making Engages Distinct Modes of Cross-Frequency Coupling

Area of Science:

• Neuroscience
• Cognitive Psychology
• Psychiatry

Background:

• The prefrontal cortex uses cross-frequency coupling to control sensory and motor systems.
• The role of these neural signals in reward-based decision-making and their alteration in major depressive episodes remain unclear.

Purpose of the Study:

• To investigate the role of prefrontal cortex cross-frequency coupling in reward-based decision-making.
• To determine if these neural dynamics are altered in individuals with major depressive episodes.

Main Methods:

• Electroencephalography (EEG) was used to record brain activity in participants with and without depression performing a reward-based decision-making task.
• Behavioral data quantified goal-directed behavior (effort for reward) and reward evaluation (incentive modulation).
• Factor analysis identified symptom dimensions in depression.

Main Results:

• Frontal-midline theta oscillation amplitude correlated positively with reward evaluation.
• Coupling between frontal theta phase and parieto-occipital gamma amplitude positively correlated with reward evaluation.
• Goal-directed behavior positively correlated with frontal delta phase and motor beta amplitude coupling.
• Mood symptoms tracked with reward evaluation, while motivation symptoms tracked with goal-directed behavior.

Conclusions:

• Two distinct modes of prefrontal top-down control instantiate different aspects of reward-based decision-making.
• These neural mechanisms are differentially modulated by distinct symptom dimensions of depression.