title: Revisiting the evidence for collapsing boundaries and urgency signals in perceptual decision-making.
abstract: For nearly 50 years, the dominant account of decision-making holds that noisy information is accumulated until a fixed threshold is crossed. This account has been tested extensively against behavioral and neurophysiological data for decisions about consumer goods, perceptual stimuli, eyewitness testimony, memories, and dozens of other paradigms, with no systematic misfit between model and data. Recently, the standard model has been challenged by alternative accounts that assume that less evidence is required to trigger a decision as time passes. Such "collapsing boundaries" or "urgency signals" have gained popularity in some theoretical accounts of neurophysiology. Nevertheless, evidence in favor of these models is mixed, with support coming from only a narrow range of decision paradigms compared with a long history of support from dozens of paradigms for the standard theory. We conducted the first large-scale analysis of data from humans and nonhuman primates across three distinct paradigms using powerful model-selection methods to compare evidence for fixed versus collapsing bounds. Overall, we identified evidence in favor of the standard model with fixed decision boundaries. We further found that evidence for static or dynamic response boundaries may depend on specific paradigms or procedures, such as the extent of task practice. We conclude that the difficulty of selecting between collapsing and fixed bounds models has received insufficient attention in previous research, calling into question some previous results.
authors: School of Psychology, University of Newcastle, Callaghan, NSW 2308, Australia, guy.e.hawkins@gmail.com.
authors: Guy E
authors: GE
authors: Hawkins
authors: Amsterdam Brain and Cognition and.
authors: Birte U
authors: BU
authors: Forstmann
authors: Department of Psychology, University of Amsterdam, Amsterdam 1018WS, The Netherlands, and.
authors: Eric-Jan
authors: EJ
authors: Wagenmakers
authors: Department of Psychology, The Ohio State University, Columbus, Ohio 43210.
authors: Roger
authors: R
authors: Ratcliff
authors: School of Psychology, University of Newcastle, Callaghan, NSW 2308, Australia.
authors: Scott D
authors: SD
authors: Brown
mesh_terms: D000465:Algorithms; D000818:Animals; D003657:Decision Making / Q000502:physiology*; D004192:Discrimination, Psychological; D005260:Female; D006801:Humans; D008253:Macaca mulatta; D008297:Male; D008959:Models, Neurological; D009039:Motion Perception; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: decision-making; diffusion model; human; nonhuman primate; response time