Isolating and Mitigating Sequentially Dependent Perceptual Errors in Clinical Visual Search

NCT04332783 | Recruiting

• 1 other identifier: R01CA236793
• Study Type: interventional
• Target: 10,120
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

Vision

Keywords

Visual Perception; Psychophysics; Visual Search

Outcome Measures

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.

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

Study Arms (2)

Healthy Typical Adults

EXPERIMENTAL

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

Behavioral: psychophysics of sequential biases (no drug or patient work)

Healthy typical adults

EXPERIMENTAL

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

Behavioral: psychophysics of sequential biases (no drug or patient work)

Interventions

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.

Healthy Typical Adults; Healthy typical adults

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

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

You may not qualify if:

• Subjects may not be under the age of 18 to participate.
• Subjects may not participate if they are blind.

Sponsors & Collaborators

• University of California, Berkeley: lead

Study Sites (1)

University of California, Berkeley

Berkeley, California, 94720, United States

RECRUITING

Study Officials

• David Whitney, PhD

  University of California, Berkeley

  PRINCIPAL INVESTIGATOR

Central Study Contacts

Katrina Wolters, BA

CONTACT

510-642-5797‬; katrinaw@berkeley.edu

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor

Study Record Dates

• First Submitted: March 31, 2020
• First Posted: April 3, 2020
• Study Start: April 1, 2019
• Primary Completion (Estimated): June 30, 2031
• Study Completion (Estimated): October 30, 2032
• Last Updated: February 3, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will share
• Shared Documents: STUDY PROTOCOL, SAP, ANALYTIC CODE
• Time Frame: Upon request or as required by peer-reviewed journals.
• Access Criteria: None; access granted on request or by journals, as required for publication; in either case, a URL will be posted to access anonymized, de-identified data via an OSF link.

Locations

US (1)