Psychophysics of Sequential Biases in Vision

Overseen By Valerie Ekko, BA

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: University of California, Berkeley

Disqualifiers: Under 18, Blind

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

1650 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial aims to understand how past experiences with x-rays affect a radiologist's ability to detect and identify tumors accurately. Researchers seek to identify when these sequential biases occur and find ways to reduce their negative impact on tumor detection. Participants will engage in computer tasks that assess their perception and decision-making in spotting tumors on x-rays. The trial seeks adults with normal vision or those who wear glasses or contacts. As an unphased trial, this study offers participants the chance to contribute to important research that could enhance diagnostic accuracy in radiology.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications.

What prior data suggests that this method is safe for participants?

Research shows no specific safety information for the treatment called "Psychophysics of Sequential Biases in Vision." This involves computer tasks where participants, including radiologists and non-radiologists, examine x-rays to identify and label tumors. As this is not a typical drug or medical procedure, it likely lacks usual safety issues like side effects. Participants engage in visual tasks on a computer, which is generally safe. However, for any concerns or questions, contacting the trial coordinators is advisable. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about the Psychophysics of Sequential Biases in Vision trial because it explores how experts like radiologists process visual information when detecting tumors in x-ray images. Unlike traditional methods that focus purely on the technology of imaging, this approach investigates the human element of diagnosis, aiming to enhance how medical professionals interpret complex visual data. By understanding these visual biases, the trial has the potential to improve diagnostic accuracy and speed, ultimately leading to better patient outcomes.

What evidence suggests that this trial's methods could improve tumor detection in x-rays?

Research has shown that when radiologists review many x-rays consecutively, their decisions can be influenced by the images they've just seen. This phenomenon, known as serial dependence, affects how they interpret current images and can lead to mistakes, such as misclassifying a tumor based on the previous x-ray. The trial will involve healthy typical adults, including radiologists and non-radiologists, participating in computer-based tasks to study these biases. The studies aim to understand and reduce these errors to help radiologists make more accurate decisions. By understanding these biases, researchers hope to make x-ray reading more reliable and improve patient care. ^{1 6 7 8 9}

Who Is on the Research Team?

David Whitney, PhD

Principal Investigator

University of California, Berkeley

Are You a Good Fit for This Trial?

This trial is for individuals with normal or corrected-to-normal vision, such as those who wear glasses or contacts. It's designed to help radiologists improve their ability to detect and classify tumors in x-rays by understanding how previous images they've seen can affect their current work.

Inclusion Criteria

My vision is normal or corrected to normal with glasses or contacts.

Exclusion Criteria

Subjects must not participate if they are blind.

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Establishing Sequential Effects

Establish the presence of sequential effects in perceptual decision making in clinically relevant tasks such as tumor detection, classification, localization, and search times.

4-8 weeks

Multiple sessions (in-person)

Identifying Visual Serial Dependence

Identify the tuning and boundary conditions of visual serial dependence in tumor search to develop strategies to mitigate its harmful consequences.

4-8 weeks

Multiple sessions (in-person)

Mitigating Visual Serial Dependence

Develop task manipulations to mitigate the impact of visual serial dependence, improving visual search performance in radiologists.

4-8 weeks

Multiple sessions (in-person)

Follow-up

Participants are monitored for improvements in visual search performance and the effectiveness of mitigation strategies.

4 weeks

What Are the Treatments Tested in This Trial?

Interventions

• No Intervention
• Psychophysics of Sequential Biases

Trial Overview The study investigates how past visual experiences bias a radiologist's perception and decisions when examining sequential x-rays. The goal is to establish these biases, identify conditions that influence them, and develop strategies to mitigate their negative effects on tumor detection and classification.

How Is the Trial Designed?

Group I: Healthy Typical Adults Experimental Treatment 1 Intervention

Observers including radiologists and non-radiologists will be asked to participate in computer based tasks in which they visually search for, detect, localize, and categorize tumors in x-ray images.

Who Is Running the Clinical Trial?

University of California, Berkeley

Lead Sponsor

Trials

193

Recruited

716,000+

Published Research Related to This Trial

The study reveals that our recent decisions influence how we perceive sensory information, suggesting that the brain continuously computes probabilities to predict future events, even in unpredictable environments.

By using different learning models in experiments with auditory, vestibular, and visual stimuli, the research shows that serial dependence in decision-making is linked to tracking statistical patterns rather than just the order of stimuli presented.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Probabilistic integration of preceding responses explains response bias in perceptual decision making. Schlunegger, D., Mast, FW.[2023]

Sequential effects in perceptual judgments, such as assimilation and contrast effects, show how our recent experiences influence our current perceptions, indicating a dynamic bias in judgment.

The proposed framework based on human M/EEG findings suggests that these sequential biases evolve over time and are integrated into our current judgments, helping to explain how we adapt our perceptions based on temporal context.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

A neural-based account of sequential bias during perceptual judgment. Hsu, SM.[2021]

Pseudosequential effects in psychophysical judgments can occur when some subjects inaccurately judge stimuli, which can skew results and lead to misleading conclusions.

Current methods for demonstrating genuine sequential effects are problematic, and there is still no definitive evidence proving that true sequence effects exist in psychophysical studies.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

[Sequence effects in absolute judgment? Critical comments on the method]. Haubensak, G.[2006]

In a study involving 20 experienced physicians and 20 medical students analyzing 234 complex radiographic images, only the medical students showed sequential context effects, indicating that their judgments were influenced by the order of images they viewed.

As medical students progressed through the training task, they shifted from making relative comparisons based on the sequence of images to relying more on their internalized standards for evaluating each image independently.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sequential dependencies in categorical judgments of radiographic images. Beckstead, JW., Boutis, K., Pecaric, M., et al.[2017]

The study found that the way people perceive visual stimuli can influence their subsequent choices in a positive manner, while their motor responses can create a repulsive effect, indicating a complex interaction between perception and action.

Individual differences in how people experience serial dependence in decision-making were highlighted, with some showing a positive bias, others a repulsive bias, and some showing no bias at all, suggesting that these differences may stem from how much weight individuals give to perceptual choices versus motor responses.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Individual difference in serial dependence results from opposite influences of perceptual choices and motor responses. Zhang, H., Alais, D.[2020]

The study shows that past decisions can bias current perceptual choices, indicating that the influence of previous decisions is a significant factor in decision-making processes.

Using a modified drift-diffusion model, the research found that keeping track of previous decisions improves the accuracy of current decisions, suggesting that decision-making is influenced by the accumulation of evidence from prior choices.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Residual Information of Previous Decision Affects Evidence Accumulation in Current Decision. Olianezhad, F., Zabbah, S., Tohidi-Moghaddam, M., et al.[2020]

In a study examining 3D motion perception, it was found that serial dependence—where decisions are influenced by previous stimuli—was stronger when the current trial had lower stimulus contrast, indicating a link between sensory uncertainty and bias.

Providing performance feedback, which reduced uncertainty, eliminated the serial dependence effect, suggesting that this bias may be a strategic response to manage uncertainty rather than a fixed perceptual mechanism.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Task feedback suggests a post-perceptual component to serial dependence. Fulvio, JM., Rokers, B., Samaha, J.[2023]

In a study involving 48 participants rating the attractiveness of male and female faces, it was found that attractiveness judgments are influenced by the ratings given in the preceding trial, demonstrating a sequential effect in subjective decision-making.

Providing participants with feedback on average attractiveness ratings from others reduced the sequential effect, indicating that external information can help mitigate biases in attractiveness judgments.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Sequential effects in face-attractiveness judgment. Kondo, A., Takahashi, K., Watanabe, K.[2017]

Citations

1. withpower.com withpower.com/trial/phase-3-2019-2276c

Psychophysics of Sequential Biases in Vision The research articles provided do not contain specific safety data for the treatment 'Psychophysics of Sequential Biases in Vision' or related interventions.

2. ctv.veeva.com ctv.veeva.com/study/isolating-and-mitigating-sequentially-dependent-perceptual-errors-in-clinical-visual-search

Isolating and Mitigating Sequentially Dependent Perceptual Errors ... The rationale for the proposed research projects is that once it is known how serial dependence arises and how it impacts visual search, we can understand how ...

3. sciencedirect.com sciencedirect.com/science/article/pii/S0042698999002448

The psychophysics of visual search Visual psychophysics provides theories of the representation of simple attributes such as color or orientation, and for the processes that yield a response in ...

4. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC9871508/

Serial dependence in visual perception: A review - PMC Sequential dependencies and regression in psychophysical judgments. Perception & Psychophysics, 14(3), 547–552, 10.3758/BF03211196. [DOI] ...

5. link.springer.com link.springer.com/article/10.3758/s13414-020-02045-8

The description-experience gap in visual search The effects of local prevalence and explicit expectations on search termination times. Attention, Perception, & Psychophysics, 74(1), 115– 123.

6. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC10902869/

Perceptual confirmation bias and decision bias underlie ... Perceptual confirmation bias and decision bias underlie adaptation to sequential regularities ... Attention, Perception, & Psychophysics, 80(7), ...

7. jneurosci.org jneurosci.org/content/43/21/3860

Perceptual History Biases Are Predicted by Early Visual- ... All the stimuli were generated using the Psychophysics Toolbox (Pelli, 1997; Kleiner et al., 2007) on MATLAB (version r2019b; The MathWorks). In ...

8. journalofcognition.org journalofcognition.org/articles/10.5334/joc.13

Visual Selection: Usually Fast and Automatic; Seldom Slow ... Perception & Psychophysics, 55, 485–496. DOI: https://doi.org/10.3758 ... The time course of attentional bias to cues of threat and safety. Cognition ...

9. edoc.ub.uni-muenchen.de edoc.ub.uni-muenchen.de/34266/2/Cheng_Si.pdf

The neural and behavioral basis of serial dependence in ... Perception & Psychophysics, 63(8), 1293–1313. Wiener, M., Thompson, J. C. ... A Bayesian and efficient observer model explains · concurrent attractive and ...