Isolating and Mitigating Sequentially Dependent Perceptual Errors in Clinical Visual Search

ConditionVision
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18+
SponsorUniversity of California, Berkeley

About this trial

Remote-store-and-forward teledermatology has recently grown exponentially in popularity and use as an efficient, accurate, and cost-effective way to improve the health and well-being of countless patients. Despite advances in machine learning and computer vision, the screening and reading of dermatological images still depends on the visual system of human observers (e.g., clinicians), who receive extensive training to best recognize lesions and anomalies. In remote store-and-forward teledermatology settings, clinicians may examine hundreds of images on a daily basis, seeing several images one after the other. A main underlying assumption of their work is that clinician percepts and decisions about a current image are completely independent from prior viewings. However, we and other groups demonstrated that the visual system has visual serial dependencies (VSDs) at many levels, from perception to decision making, including in clinical tasks. These sequential dependencies, replicated hundreds of times in the literature, mean that what was seen in the past influences (and captures) what is seen and reported at this moment. Theoretically, VSDs are helpful in an autocorrelated natural world, but they are suboptimal in visual tasks conducted in artificial situations where images are not always related. Importantly, serial dependencies in perceptual processing could thus produce significant errors during diagnostic judgments of dermatological images. Our central hypothesis is that VSD can have a disruptive effect in asynchronous remote-store-and-forward teledermatology judgments that impairs accurate detection and recognition of lesions. This hypothesis is supported by our robust pilot data, which show that VSD strongly biases lesion classification in both untrained observers and expert clinicians. The rationale for the proposed research projects is that once it is known how serial dependence arises and how it impacts judgments, we can understand how to control for it. Hence, accuracy of lesion detection and diagnosis can significantly improve. The specific objectives of this proposal are to establish (Aim 1), identify (Aim 2) and mitigate (Aim 3) the impact of VSD on remote-store-and-forward dermatological judgments.

Eligibility criteria

This trial accepts healthy volunteers

Qualifiers

Subjects must have normal or corrected to normal vision with contacts or glasses.

Disqualifiers

Subjects may not be under the age of 18 to participate.

Subjects may not participate if they are blind.

Trial design

Design model

Single group

Treatments tested in this trial

  • psychophysics of sequential biases (no drug or patient work)

    Behavioral

    Psychophysical experiment on sequential effects in medical image perception. Observers, including clinicians, perform psychophysical continuous report match-to-sample and forced-choice discrimination judgments of medical images. Observer discrimination accuracy is measured on a trial-wise basis and sequential effects in those judgments are measured. Images can be presented with different interstimulus intervals and in different spatial locations and in different orders. Accuracy, and other signal detection metrics are computed as a function of these factors.

Treatment groups

10,120 Participants
are divided into 2 treatment groups
Group A: Healthy Typical AdultsExperimental treatment 1 intervention
Group B: Healthy typical adultsExperimental treatment 1 intervention

Trial outcomes

Primary outcomes

1

Serial Dependence Assessment using psychophysical procedures

This is a medical image perception experiment using psychophysical methods, including continuous report match-to-sample and method-of-constant stimuli designs. Human observers, including clinicians and untrained observers, are recruited to classify or discriminate medical images. Each observer participates in approximately 300 trials in a session. On each trial, observers view a medical image on a computer monitor and are asked to make either a match-to-sample or a two-alternative forced choice decisions about the image. Observer responses on each trial are classified in terms of their accuracy. Outcome measures include hit rate, false alarm rate, sensitivity, selectivity, d', and criterion. Changes in these metrics from trial-to-trial throughout the course of the experiment are quantified as metrics of sequential biases that might be present in observer judgments.

Time frame
Each participant is tested for 30-60 minutes in a psychophysical experiment.

Secondary outcomes

Other outcomes

Sponsors and contacts

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