Mortimer B. Zuckerman Mind Brain Behavior Institute and The Kavli Institute for Brain Science, Columbia University, New York, United States; Department of Brain and Cognitive Sciences, University of Rochester, Rochester, United States
Jochen Ditterich
Center for Neuroscience and Department of Neurobiology, Physiology & Behavior, University of California, Davis, United States
Department of Neuroscience, Columbia University, New York, United States; Mortimer B. Zuckerman Mind Brain Behavior Institute and The Kavli Institute for Brain Science, Columbia University, New York, United States; Howard Hughes Medical Institute, Columbia University, New York, United States
Many tasks used to study decision-making encourage subjects to integrate evidence over time. Such tasks are useful to understand how the brain operates on multiple samples of information over prolonged timescales, but only if subjects actually integrate evidence to form their decisions. We explored the behavioral observations that corroborate evidence-integration in a number of task-designs. Several commonly accepted signs of integration were also predicted by non-integration strategies. Furthermore, an integration model could fit data generated by non-integration models. We identified the features of non-integration models that allowed them to mimic integration and used these insights to design a motion discrimination task that disentangled the models. In human subjects performing the task, we falsified a non-integration strategy in each and confirmed prolonged integration in all but one subject. The findings illustrate the difficulty of identifying a decision-maker’s strategy and support solutions to achieve this goal.
