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Full-Text Articles in Behavior and Behavior Mechanisms

An Integration-To-Bound Model Of Decision-Making That Accounts For The Spectral Properties Of Neural Data, Ramón Guevara Erra, Marco Arbotto, Aaron Schurger Jun 2019

An Integration-To-Bound Model Of Decision-Making That Accounts For The Spectral Properties Of Neural Data, Ramón Guevara Erra, Marco Arbotto, Aaron Schurger

Psychology Faculty Articles and Research

Integration-to-bound models are among the most widely used models of perceptual decision-making due to their simplicity and power in accounting for behavioral and neurophysiological data. They involve temporal integration over an input signal (“evidence”) plus Gaussian white noise. However, brain data shows that noise in the brain is long-term correlated, with a spectral density of the form 1/fα (with typically 1 < α < 2), also known as pink noise or ‘1/f’ noise. Surprisingly, the adequacy of the spectral properties of drift-diffusion models to electrophysiological data has received little attention in the literature. Here we propose a model of accumulation of evidence for decision-making that takes into consideration the spectral properties of brain signals. We develop a generalization of the leaky stochastic accumulator model using a Langevin equation whose non-linear noise term allows for varying levels of autocorrelation in the time course of the decision variable. We derive this equation directly from magnetoencephalographic data recorded while subjects performed a spontaneous movement initiation task. We then propose a nonlinear model of accumulation of evidence that accounts for the ‘1/f’ spectral properties of brain signals, and the observed variability in the power spectral properties of brain signals. Furthermore, our model outperforms the standard drift-diffusion model at approximating the empirical waiting time distribution.


Rationale, Design, And Baseline Characteristics Of Walkit Arizona: A Factorial Randomized Trial Testing Adaptive Goals And Financial Reinforcement To Increase Walking Across Higher And Lower Walkable Neighborhoods, Marc A. Adams, Jane Hurley, Christine Phillips, Michael Todd, Siddhartha Angadi, Vincent Berardi, Melbourne F. Hovell, Steven Hooker May 2019

Rationale, Design, And Baseline Characteristics Of Walkit Arizona: A Factorial Randomized Trial Testing Adaptive Goals And Financial Reinforcement To Increase Walking Across Higher And Lower Walkable Neighborhoods, Marc A. Adams, Jane Hurley, Christine Phillips, Michael Todd, Siddhartha Angadi, Vincent Berardi, Melbourne F. Hovell, Steven Hooker

Psychology Faculty Articles and Research

Little change over the decades has been seen in adults meeting moderate-to-vigorous physical activity (MVPA) guidelines. Numerous individual-level interventions to increase MVPA have been designed, mostly static interventions without consideration for neighborhood context. Recent technologies make adaptive interventions for MVPA feasible. Unlike static interventions, adaptive intervention components (e.g., goal setting) adjust frequently to an individual's performance. Such technologies also allow for more precise delivery of “smaller, sooner incentives” that may result in greater MVPA than “larger, later incentives”. Combined, these factors could enhance MVPA adoption. Additionally, a central tenet of ecological models is that MVPA is sensitive to neighborhood environment …


Delay Discount Rate Moderates A Physical Activity Intervention Testing Immediate Rewards, Christine B. Phillips, Jane C. Hurley, Siddhartha S. Angadi, Michael Todd, Vincent Berardi, Melbourne Hovell, Marc A. Adams Apr 2019

Delay Discount Rate Moderates A Physical Activity Intervention Testing Immediate Rewards, Christine B. Phillips, Jane C. Hurley, Siddhartha S. Angadi, Michael Todd, Vincent Berardi, Melbourne Hovell, Marc A. Adams

Psychology Faculty Articles and Research

Financial incentives can increase physical activity (PA), but differences in the immediacy of reward delivery and individual differences in delay discount rates (i.e., higher discount values associated with less tolerance for delayed rewards) may explain differential responding. The current study tested whether delay discount rate moderated the relative effectiveness of immediate financial rewards on increasing daily PA. Inactive, overweight adults (ages 18–60, N = 96) were randomized to receive either smaller, immediate goal-contingent rewards or larger, delayed rewards for participation. Delay discount rates were derived for those who completed the Monetary Choice Questionnaire (N = 85). Linear mixed models tested …