Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, United States; Department of Engineering, University of Cambridge, Cambridge, United Kingdom
Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, United States; Kavli Institute for Brain Science, Columbia University, New York, United States
Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, United States; Howard Hughes Medical Institute, Columbia University, New York, United States
Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, United States; Department of Brain and Cognitive Sciences, University of Rochester, Rochester, United States
Zuckerman Mind Brain Behavior Institute, Department of Neuroscience, Columbia University, New York, United States; Kavli Institute for Brain Science, Columbia University, New York, United States; Howard Hughes Medical Institute, Columbia University, New York, United States
The brain is capable of processing several streams of information that bear on different aspects of the same problem. Here, we address the problem of making two decisions about one object, by studying difficult perceptual decisions about the color and motion of a dynamic random dot display. We find that the accuracy of one decision is unaffected by the difficulty of the other decision. However, the response times reveal that the two decisions do not form simultaneously. We show that both stimulus dimensions are acquired in parallel for the initial ∼0.1 s but are then incorporated serially in time-multiplexed bouts. Thus, there is a bottleneck that precludes updating more than one decision at a time, and a buffer that stores samples of evidence while access to the decision is blocked. We suggest that this bottleneck is responsible for the long timescales of many cognitive operations framed as decisions.