Comparing signal detection models of perceptual decision confidence

When forced to choose humans often feel uncertain. Investigations of human perceptual decision-making often employ signal detection theory, which assumes that even when uncertain all available information is fully utilized. However, other studies have suggested or assumed that, when uncertain, human subjects guess totally at random, ignoring available information. When uncertain, do humans simply guess totally at random? Or do humans fully utilize complete information? Or does behavior fall between these two extremes yielding “above chance” performance without fully utilizing complete information? While it is often assumed complete information is fully utilized, even when uncertain, to our knowledge this has never been experimentally confirmed. To answer this question, we combined numerical simulations, theoretical analyses, and human studies performed using a self-motion direction-recognition perceptual decision-making task (did I rotate left or right?). Subjects were instructed to make forced-choice binary (left/right) and trinary (left/right/uncertain) decisions when cued following each stimulus. Our results show that humans 1) do not guess at random when uncertain and 2) make binary and trinary decisions equally well. These findings show that humans fully utilize complete information when uncertain for our perceptual decision-making task. This helps unify signal detection theory and other models of forced-choice decision-making which allow for uncertain responses. NEW & NOTEWORTHY Humans make many perceptual decisions every day. But what if we are uncertain? While many studies assume that humans fully utilize complete information, other studies have suggested and/or assumed that when we're uncertain and forced to decide, information is not fully utilized. While humans tend to perform above chance when uncertain, no earlier study has tested whether available information is fully utilized. Our results show that humans make fully informed decisions even when uncertain.

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Modelling visibility judgments using models of decision confidence

10.31219/osf.io/7dakz ◽

2018 ◽

Cited By ~ 3

Author(s):

Manuel Rausch ◽

Michael Zehetleitner

Keyword(s):

Signal Detection ◽

Visual Experience ◽

Channel Model ◽

Identification Task ◽

Detection Model ◽

Decision Confidence ◽

Standard Signal ◽

Sensory Evidence ◽

Evidence Model ◽

Subjective Reports

How can we explain the regularities in subjective reports of human observers about their subjective visual experience of a stimulus? The present study tests if a recent model of decisional confidence, the weighted evidence and visibility model, can be generalized from confidence to subjective visibility. In a masked orientation identification task, observers reported the subjective visibility of the stimulus after each single identification response. Cognitive modelling revealed that the weighted evidence and visibility model provided a superior fit to the data compared to the standard signal detection model, the signal detection model with unsystematic noise superimposed on ratings, the postdecisional accumulation model, the two-channel model, the response-congruent evidence model, the two-dimensional Bayesian model, and the constant noise and decay model. A comparison between subjective visibility and decisional confidence revealed that visibility relied more on the strength of sensory evidence about features of the stimulus irrelevant to the identification judgment and less on evidence for the identification judgment. It is argued that at least two types of evidence are required to account for subjective visibility, one related to the identification judgment, and one related to the strength of stimulation.

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Neural Mediators of Altered Perceptual Choice and Confidence Using Social Information

10.1101/516963 ◽

2019 ◽

Author(s):

Tiasha Saha Roy ◽

Bapun Giri ◽

Arpita Saha Chowdhury ◽

Satyaki Mazumder ◽

Koel Das

Keyword(s):

Decision Making ◽

Frontal Cortex ◽

Visual Processing ◽

Social Information ◽

Social Cues ◽

Perceptual Decision Making ◽

Neural Data ◽

Perceptual Decision ◽

Decision Confidence ◽

Significant Difference

AbstractUnderstanding how individuals utilize social information while making perceptual decisions and how it affects their decision confidence is crucial in a society. Till date, very little is known about perceptual decision making in humans under the influence of social cues and the associated neural mediators. The present study provides empirical evidence of how individuals get manipulated by social cues while performing a face/car identification task. Subjects were significantly influenced by what they perceived as decisions of other subjects while the cues in reality were manipulated independently from the stimulus. Subjects in general tend to increase their decision confidence when their individual decision and social cues coincide, while their confidence decreases when cues conflict with their individual judgments often leading to reversal of decision. Using a novel statistical model, it was possible to rank subjects based on their propensity to be influenced by social cues. This was subsequently corroborated by analysis of their neural data. Neural time series analysis revealed no significant difference in decision making using social cues in the early stages unlike neural expectation studies with predictive cues. Multivariate pattern analysis of neural data alludes to a potential role of frontal cortex in the later stages of visual processing which appeared to code the effect of social cues on perceptual decision making. Specifically medial frontal cortex seems to play a role in facilitating perceptual decision preceded by conflicting cues.

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Superior colliculus signals decisions rather than confidence: analysis of single neurons

Journal of Neurophysiology ◽

10.1152/jn.00152.2018 ◽

2018 ◽

Vol 120 (5) ◽

pp. 2614-2629 ◽

Cited By ~ 6

Author(s):

Piercesare Grimaldi ◽

Seong Hah Cho ◽

Hakwan Lau ◽

Michele A. Basso

Keyword(s):

Superior Colliculus ◽

Neuronal Cell ◽

Population Level ◽

Cell Types ◽

Perceptual Information ◽

Decision Accuracy ◽

Lateral Intraparietal Area ◽

Perceptual Decision ◽

Decision Confidence ◽

Normative Models

Recent findings indicate that monkeys can report their confidence in perceptual decisions and that this information is encoded in neurons involved in making decisions, including the lateral intraparietal area (LIP) and the supplementary eye field (SEF). A key issue to consider when studying confidence is that decision accuracy often correlates with confidence reports; when we are performing well, we generally feel more confident. Expanding on work performed in humans, we designed a novel task for monkeys that dissociates perceptual information leading to decisions from perceptual information leading to confidence reports. Using this task, we recently showed that decoded ensemble activity recorded from the superior colliculus (SC) reflected decisions rather than confidence reports. However, our previous population level analysis collapsed over multiple SC neuronal types and therefore left open the possibility that first, individual discharge rates might encode information related to decision confidence, and second, different neuronal cell types within the SC might signal decision confidence independently of decision accuracy. We found that when decision accuracy and decision confidence covaried, modulation occurred primarily in neurons with prelude activity (buildup neurons). However, isolating decision confidence from decision accuracy uncovered that only a few, primarily buildup neurons showed signals correlating uniquely with decision confidence and the effect sizes were very small. Based on this work and our previous work using decoding methods, we conclude that neuronal signals for decision confidence, independent of decision accuracy, are unlikely to exist at the level of single or populations of neurons in the SC. Our results together with other recent work call into question normative models of confidence based on the optimal readout of decision signals. NEW & NOTEWORTHY Models of decision confidence suggest that our sense of confidence is an optimal readout of perceptual decision signals. Here, we report that a subcortical area, the superior colliculus (SC), contains neurons with activity that signal decisions and confidence in a task in which decision accuracy and confidence covary, similar to area lateral intraparietal area in cortex. The signals from SC occur primarily in the neurons with prelude activity (buildup neurons). However, in a task that dissociates decision accuracy from decision confidence, we find that only a few individual neurons express unique signals of confidence. These results call into question normative models of confidence based on optimal readout of perceptual decision signals.

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Modelling visibility judgments using models of decision confidence

Attention Perception & Psychophysics ◽

10.3758/s13414-021-02284-3 ◽

2021 ◽

Author(s):

Manuel Rausch ◽

Sebastian Hellmann ◽

Michael Zehetleitner

Keyword(s):

Signal Detection ◽

Visual Experience ◽

Channel Model ◽

Identification Task ◽

Detection Model ◽

Decision Confidence ◽

Standard Signal ◽

Sensory Evidence ◽

Evidence Model ◽

Subjective Reports

AbstractHow can we explain the regularities in subjective reports of human observers about their subjective visual experience of a stimulus? The present study tests whether a recent model of confidence in perceptual decisions, the weighted evidence and visibility model, can be generalized from confidence to subjective visibility. In a postmasked orientation identification task, observers reported the subjective visibility of the stimulus after each single identification response. Cognitive modelling revealed that the weighted evidence and visibility model provided a superior fit to the data compared with the standard signal detection model, the signal detection model with unsystematic noise superimposed on ratings, the postdecisional accumulation model, the two-channel model, the response-congruent evidence model, the two-dimensional Bayesian model, and the constant noise and decay model. A comparison between subjective visibility and decisional confidence revealed that visibility relied more on the strength of sensory evidence about features of the stimulus irrelevant to the identification judgment and less on evidence for the identification judgment. It is argued that at least two types of evidence are required to account for subjective visibility, one related to the identification judgment, and one related to the strength of stimulation.

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Separable neural signatures of confidence during perceptual decisions

eLife ◽

10.7554/elife.68491 ◽

2021 ◽

Vol 10 ◽

Author(s):

Tarryn Balsdon ◽

Pascal Mamassian ◽

Valentin Wyart

Keyword(s):

Decision Making ◽

Neural Circuit ◽

Spectral Power ◽

Brain Activity ◽

Neural Representation ◽

Perceptual Decision Making ◽

Perceptual Decision ◽

Decision Confidence ◽

Electrical Brain Activity ◽

Human Participants

Perceptual confidence is an evaluation of the validity of perceptual decisions. While there is behavioural evidence that confidence evaluation differs from perceptual decision-making, disentangling these two processes remains a challenge at the neural level. Here, we examined the electrical brain activity of human participants in a protracted perceptual decision-making task where observers tend to commit to perceptual decisions early whilst continuing to monitor sensory evidence for evaluating confidence. Premature decision commitments were revealed by patterns of spectral power overlying motor cortex, followed by an attenuation of the neural representation of perceptual decision evidence. A distinct neural representation was associated with the computation of confidence, with sources localised in the superior parietal and orbitofrontal cortices. In agreement with a dissociation between perception and confidence, these neural resources were recruited even after observers committed to their perceptual decisions, and thus delineate an integral neural circuit for evaluating perceptual decision confidence.

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The positive evidence bias in perceptual confidence is not post-decisional

10.1101/2020.03.15.991513 ◽

2020 ◽

Cited By ~ 2

Author(s):

Jason Samaha ◽

Rachel Denison

Keyword(s):

Signal Detection ◽

Decision Processes ◽

Memory Bias ◽

Perceptual Task ◽

Positive Evidence ◽

Perceptual Decision ◽

Evidence Accumulation ◽

Subjective Estimate ◽

Perceptual Confidence ◽

Stimulus Offset

AbstractConfidence in a perceptual decision is a subjective estimate of the accuracy of one’s choice. As such, confidence is thought to be an important computation for a variety of cognitive and perceptual processes, and it features heavily in theorizing about conscious access to perceptual states. Recent experiments have revealed a “positive evidence bias” (PEB) in the computations underlying confidence reports. A PEB occurs when confidence, unlike objective choice, over-weights the evidence for the chosen option, relative to evidence against the chosen option. Accordingly, in a perceptual task, appropriate stimulus conditions can be arranged that produce selective changes in confidence reports but no changes in accuracy. Although the PEB is generally assumed to reflect the observer’s perceptual and/or decision processes, post-decisional accounts have not been ruled out. We therefore asked whether the PEB persisted under novel conditions that eliminated two possible post-decisional accounts: 1) post-decision evidence accumulation that contributes to a confidence report solicited after the perceptual choice, and 2) a memory bias that emerges in the delay between the stimulus offset and the confidence report. We found that even when the stimulus remained on the screen until observers responded, and when observers reported their choice and confidence simultaneously, the PEB still emerged. Signal detection-based modeling also showed that the PEB was not associated with changes to metacognitive efficiency, but rather to confidence criteria. We conclude that once-plausible post-decisional accounts of the PEB do not explain the bias, bolstering the idea that it is perceptual or decisional in nature.

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