Global gain modulation generates time-dependent urgency during perceptual choice in humans

Area of Science:

• Cognitive Neuroscience
• Decision Science
• Computational Neuroscience

Background:

• Optimal decision-making involves balancing information gathering with deliberation costs.
• Dynamic adjustment of the speed/accuracy trade-off is crucial for reward maximization.
• Human capacity for time-dependent decision adjustments remains unclear.

Purpose of the Study:

• To identify signatures of time-dependency in human perceptual decision-making.
• To explore the neural underpinnings of these time-dependent adjustments.
• To investigate the role of neural gain modulation in decision urgency.

Main Methods:

• Behavioral analyses of perceptual decision-making under deadline pressure.
• Model-based analyses to quantify decision strategies.
• Electrophysiological and pupillometry measures to assess neural activity and gain modulation.

Main Results:

• Subjects lowered their evidence criterion as deadlines approached, indicating increased speed pressure.
• Evidence-independent urgency signals were observed, pushing motor preparation closer to a threshold.
• Task-related pupil diameter fluctuations correlated with neural gain modulation, suggesting a mechanism for urgency.

Conclusions:

• Human perceptual decision-making exhibits context-sensitive time-dependency.
• Urgency signals, modulated by neural gain, are a key component of these dynamic adjustments.
• Findings highlight the flexibility of human decision processes in response to temporal constraints.