Speeded saccadic and manual visuo-motor decisions: Distinct processes but same principles

Area of Science:

• Cognitive Neuroscience
• Computational Neuroscience
• Decision Science

Background:

• Action selection models often use the saccadic eye movement system as a universal decision model.
• Manual response systems, like button presses, have distinct neural pathways and response characteristics.
• Understanding cross-modal decision-making principles is crucial for comprehensive action selection theories.

Purpose of the Study:

• To investigate if core concepts of action selection generalize from saccadic eye movements to manual responses.
• To identify similarities and differences in decision mechanisms across different motor effectors.
• To test the applicability of existing models to diverse response modalities.

Main Methods:

• Utilized the remote distractor effect (RDE) and 'saccadic inhibition' to compare saccadic and manual responses.
• Employed a biologically-inspired computational model (DINASAUR) to simulate and analyze response data.
• Adjusted model parameters to account for differences in input dynamics and non-decisional delays.

Main Results:

• Manual responses showed sensitivity to visual distractor interference, but to a lesser extent and over a shorter time window than saccades.
• The DINASAUR model successfully replicated both saccadic and manual response distributions and accuracy.
• Model adjustments reflected known neurophysiological and anatomical differences between saccadic and manual control networks.

Conclusions:

• Fundamental decision-making principles are conserved across different action modalities (saccadic and manual).
• Quantitative variations in parameters like input timing and non-decisional delays explain apparent qualitative differences in the literature.
• Action selection models can be generalized across effectors by accounting for specific network characteristics.