Trading accuracy for speed over the course of a decision

Humans and other animals often need to balance the desire to gather sensory information (to make the best choice) with the urgency to act, facing a speed-accuracy tradeoff (SAT). Given the ubiquity of SAT across species, extensive research has been devoted to understanding the computational mechanisms allowing its regulation at different timescales, including from one context to another, and from one decision to another. However, animals must frequently change their SAT on even shorter timescales - i.e., over the course of an ongoing decision - and little is known about the mechanisms that allow such rapid adaptations. The present study aimed at addressing this issue. Human subjects performed a decision task with changing evidence. In this task, subjects received rewards for correct answers but incurred penalties for mistakes. An increase or a decrease in penalty occurring halfway through the trial promoted rapid SAT shifts, favoring speeded decisions either in the early or in the late stage of the trial. Importantly, these shifts were associated with stage-specific adjustments in the accuracy criterion exploited for committing to a choice. Those subjects who decreased the most their accuracy criterion at a given decision stage exhibited the highest gain in speed, but also the highest cost in terms of performance accuracy at that time. Altogether, the current findings offer a unique extension of previous work, by suggesting that dynamic changes in accuracy criterion allow the regulation of the SAT within the timescale of a single decision.

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Dynamic changes in urgency over the course of a decision

10.1101/2020.04.02.022327 ◽

2020 ◽

Author(s):

Gerard Derosiere ◽

David Thura ◽

Paul Cisek ◽

Julie Duque

Keyword(s):

Late Stage ◽

Human Subjects ◽

Sensory Information ◽

Dynamic Environments ◽

Unique Extension ◽

Dynamic Changes ◽

Decision Stage ◽

Accuracy Criterion ◽

Speed Accuracy ◽

Accuracy Tradeoff

AbstractWhile making decisions, humans and other animals always need to balance the desire to gather sensory information (to make the best choice) with the urge to act, facing a speed-accuracy tradeoff (SAT). Given the ubiquity of the SAT across species, extensive research has been devoted to understanding the computational mechanisms allowing its regulation at different timescales, including from one context to another, and from one decision to another. However, in dynamic environments, animals often need to change their SAT on even shorter timescales – i.e., over the course of an ongoing decision – and very little is known about the mechanisms that allow such rapid adaptations. The present study aimed at addressing this issue. Human subjects performed a modified version of the tokens task, where an increase or a decrease in penalty occurring halfway through the trial promoted rapid SAT shifts, favoring speeded decisions either in the early or in the late stage of the trial. Importantly, these shifts were associated with stage-specific adjustments in the accuracy criterion exploited for committing to a choice and relatedly, with dynamic, non-linear changes in urgency. Those subjects who decreased the most their accuracy criterion at a given decision stage presented the highest gain in speed, but also the highest cost in terms of accuracy at that time. Altogether, the current findings offer a unique extension of former work, by revealing that dynamic changes in urgency allow the regulation of the SAT within the timescale of a single decision.

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Adaptive integration of habits into depth-limited planning defines a habitual-goal–directed spectrum

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1609094113 ◽

2016 ◽

Vol 113 (45) ◽

pp. 12868-12873 ◽

Cited By ~ 62

Author(s):

Mehdi Keramati ◽

Peter Smittenaar ◽

Raymond J. Dolan ◽

Peter Dayan

Keyword(s):

Decision Making ◽

Decision Process ◽

Time Pressure ◽

Human Subjects ◽

Mental Simulation ◽

Adaptive Integration ◽

Accurate Evaluation ◽

The Cost ◽

Speed Accuracy ◽

Accuracy Tradeoff

Behavioral and neural evidence reveal a prospective goal-directed decision process that relies on mental simulation of the environment, and a retrospective habitual process that caches returns previously garnered from available choices. Artificial systems combine the two by simulating the environment up to some depth and then exploiting habitual values as proxies for consequences that may arise in the further future. Using a three-step task, we provide evidence that human subjects use such a normative plan-until-habit strategy, implying a spectrum of approaches that interpolates between habitual and goal-directed responding. We found that increasing time pressure led to shallower goal-directed planning, suggesting that a speed-accuracy tradeoff controls the depth of planning with deeper search leading to more accurate evaluation, at the cost of slower decision-making. We conclude that subjects integrate habit-based cached values directly into goal-directed evaluations in a normative manner.

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The Role of Cerebral Metabolism in Improving Time Pressured Decisions

Frontiers in Psychology ◽

10.3389/fpsyg.2021.690198 ◽

2021 ◽

Vol 12 ◽

Author(s):

An Thanh Vu ◽

David A. Feinberg

Keyword(s):

Time Pressure ◽

Cerebral Metabolism ◽

Human Subjects ◽

Sensory Information ◽

Oxygen Metabolism ◽

Initial Dip ◽

And Behavior ◽

Speed Accuracy ◽

Speed And Accuracy

Speed-accuracy tradeoff (SAT) theory dictates that decisions can be made more quickly by sacrificing accuracy. Here we investigate whether the human brain can operate in a brief metabolic overdrive to overcome SAT and successfully make decisions requiring both high levels of speed and accuracy. In the context of BOLD fMRI we expect “a brief metabolic overdrive” to involve an increase in cerebral oxygen metabolism prior to increased cerebral blood flow–a phenomenon known as the “initial dip” which results from a sudden drop in oxyhemoglobin in perfusing blood. Human subjects performed a motion discrimination task consisting of different difficulties while emphasizing either accuracy (i.e., without time pressure) or both speed and accuracy (i.e., with time pressure). Using simultaneous multi-slice fMRI, for very fast (333 ms) measurement of whole brain BOLD activity, revealed two modes of physiological overdrive responses when subjects emphasized both speed and accuracy. The majority of subjects exhibited the hypothesized enhancement of initial dip amplitude in posterior visual cortex (PVC) with the size of the enhancement significantly correlated with improvement in behavioral performance. For these subjects, the traditionally analyzed post-stimulus overshoot was not affected by task emphasis. These results demonstrate the complexity and variability of the BOLD hemodynamic response. The discovered relationships between BOLD response and behavior were only observed when subjects emphasized both speed and accuracy in more difficult trials suggesting that the brain can perform in a state of metabolic overdrive with enhanced neural processing of sensory information specifically in challenging situations.

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Neuroticism and Speed-Accuracy Tradeoff in Self-Paced Speeded Mental Addition and Comparison

Journal of Individual Differences ◽

10.1027/1614-0001/a000021 ◽

2010 ◽

Vol 31 (3) ◽

pp. 130-137 ◽

Cited By ~ 12

Author(s):

Hagen C. Flehmig ◽

Michael B. Steinborn ◽

Karl Westhoff ◽

Robert Langner

Keyword(s):

Reaction Time ◽

Response Speed ◽

Time Variability ◽

Reaction Time Variability ◽

Comparison Task ◽

Processing Efficiency ◽

Mental Addition ◽

Speed Accuracy ◽

The Relationship ◽

Accuracy Tradeoff

Previous research suggests a relationship between neuroticism (N) and the speed-accuracy tradeoff in speeded performance: High-N individuals were observed performing less efficiently than low-N individuals and compensatorily overemphasizing response speed at the expense of accuracy. This study examined N-related performance differences in the serial mental addition and comparison task (SMACT) in 99 individuals, comparing several performance measures (i.e., response speed, accuracy, and variability), retest reliability, and practice effects. N was negatively correlated with mean reaction time but positively correlated with error percentage, indicating that high-N individuals tended to be faster but less accurate in their performance than low-N individuals. The strengthening of the relationship after practice demonstrated the reliability of the findings. There was, however, no relationship between N and distractibility (assessed via measures of reaction time variability). Our main findings are in line with the processing efficiency theory, extending the relationship between N and working style to sustained self-paced speeded mental addition.

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