Neural mechanisms of speed-accuracy tradeoff

Area of Science:

• Neuroscience
• Cognitive Science
• Computational Neuroscience

Background:

• Intelligent agents balance response speed and decision accuracy.
• Stochastic accumulator models explain this speed-accuracy tradeoff via response threshold adjustments.
• Neural correlates of this tradeoff are not well-described.

Purpose of the Study:

• Investigate the neurophysiological mechanisms of speed-accuracy tradeoff.
• Examine neural activity in the frontal eye field during a speed-accuracy task.
• Compare experimental findings with predictions from stochastic accumulator models.

Main Methods:

• Trained macaque monkeys on a visual search task requiring speed-accuracy tradeoffs.
• Recorded neuronal activity in the frontal eye field.
• Analyzed modulations in visually responsive and movement neurons.

Main Results:

• Speed-accuracy tradeoff involves distinct neural adjustments beyond threshold.
• Visually responsive neurons modulated baseline firing rate, sensory gain, and processing duration.
• Movement neurons showed activity modulation opposite to model predictions.

Conclusions:

• Current stochastic accumulator models provide an incomplete account of speed-accuracy tradeoffs.
• A diverse set of neural mechanisms contributes to this cognitive function.
• An integrated accumulator model, considering motor system constraints, reconciles these findings.