Catecholamine precursor modulation of human exploration: Evidence from a large gender-balanced sample

Area of Science:

• Neuroscience
• Cognitive Psychology
• Computational Psychiatry

Background:

• The catecholamine precursor Tyrosine is associated with cognitive enhancement.
• Its specific effects on decision-making and reinforcement learning, processes modulated by catecholamines, are not well understood.

Purpose of the Study:

• To investigate the impact of a single 2g dose of Tyrosine on reinforcement learning and exploration.
• To explore the computational mechanisms underlying Tyrosine's effects on decision-making.

Main Methods:

• A within-subjects, preregistered study with 63 participants.
• Assessment of reinforcement learning and exploration following Tyrosine administration.
• Computational modeling using established reinforcement learning models.

Main Results:

• Tyrosine significantly improved reinforcement learning performance.
• Computational modeling indicated increased value-driven exploitation and reduced directed exploration under Tyrosine.
• Further analysis revealed reductions in value-independent perseveration.

Conclusions:

• Tyrosine enhances reinforcement learning by increasing exploitation and reducing exploration, stabilizing choice patterns to optimize reward accumulation.
• These findings highlight Tyrosine's role in modulating catecholamine-influenced computational mechanisms relevant to decision-making.