NCT06281457

Brief Summary

How does one know what to look at in a scene? Imagine a "Where's Waldo" game - it's challenging to find Waldo because there are many 'salient' locations in the picture, each vying for one's attention. One can only attend to a small location on the picture at a given moment, so to find Waldo, one needs to direct their attention to different locations. One prominent theory about how one accomplishes this claims that important locations are identified based on distinct feature types (for example, motion or color), with locations most unique compared to the background most likely to be attended. An important component of this theory is that individual feature dimensions (again, color or motion) are computed within their own 'feature maps', which are thought to be implemented in specific brain regions. However, whether and how specific brain regions contribute to these feature maps remains unknown. The goal of this study is to determine how brain regions that respond strongly to different feature types (color and motion) and which encode spatial locations of visual stimuli transform 'feature dimension maps' based on stimulus properties as a function of task instructions. The investigators hypothesize that feature-selective brain regions act as neural feature dimension maps, and thus encode representations of relevant location(s) based on their preferred feature dimension, such that the stimulus representation in the most relevant feature map is up-regulated to support adaptive behavior. The investigators will scan healthy human participants using functional MRI (fMRI) in a repeated-measures design while they view visual stimuli made relevant based on a cued feature dimension (e.g., color or motion). The investigators will employ state-of-the-art multivariate analysis techniques that allow them to reconstruct an 'image' of the stimulus representation encoded by each brain region to dissect how neural tissue identifies salient locations. Each participant will perform a challenging discrimination task based on the cued feature (report motion direction or color of stimulus dots) of a stimulus presented in the periphery, which are identical across trial types. Across trials the investigators will manipulate the attended feature value (color, motion, or fixation point). This manipulation will help the investigators fully understand these critical relevance computations in the healthy human visual system.

Trial Health

55
Monitor

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Enrollment
10

participants targeted

Target at below P25 for not_applicable

Timeline
Completed

Started Apr 2024

Geographic Reach
1 country

1 active site

Status
enrolling by invitation

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

February 16, 2024

Completed
12 days until next milestone

First Posted

Study publicly available on registry

February 28, 2024

Completed
1 month until next milestone

Study Start

First participant enrolled

April 1, 2024

Completed
9 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2024

Completed
6 months until next milestone

Study Completion

Last participant's last visit for all outcomes

June 30, 2025

Completed
Last Updated

August 21, 2024

Status Verified

August 1, 2024

Enrollment Period

9 months

First QC Date

February 16, 2024

Last Update Submit

August 19, 2024

Conditions

Outcome Measures

Primary Outcomes (3)

  • Blood Oxygenation Level Dependent (BOLD) fMRI signal

    The investigators will use BOLD activation patterns measured from each retinotopic ROI to fit quantitative models of spatial encoding. These models will be used to reconstruct stimulus representations on experimental trials to quantify how stimulus representations are encoded in each brain region studied, and how these representations change across experimental manipulations. These measurements will be used to test the impact of stimulus manipulations on stimulus representations in different brain regions.

    Through study completion, an average of two weeks

  • Gaze position

    The investigators will use the measured gaze position in (x,y) coordinates to verify stable fixation throughout the experiment. Trials with poor fixation performance may be excluded from further analyses.

    Through study completion, an average of two weeks

  • Behavioral response (button press)

    On attend-fixation trials, participants will be instructed to attend carefully to the fixation point and report the shape of a target '+' (wide or tall) by pressing one of two buttons held in their hand inside the scanner. The left button will indicate wide; the right button will indicate tall. On attend-color trials, participants will report whether more dots of the attended stimulus are orange (left button) or cyan (right button). On attend-motion trials, participants will report whether more of the dots of the attended stimulus are moving counterclockwise (left button) or clockwise (right button). The investigators will ensure participants are performing the task as instructed by assessing the accuracy of their behavioral responses.

    Through study completion, an average of two weeks

Study Arms (1)

Manipulations of task demands (Expt 2.1)

EXPERIMENTAL

Participants will view a single stimulus containing dots moving in one of two directions (clock-wise or counterclockwise) and drawn in one of two colors (orange and cyan). To complete the correct task for a trial, a cue at fixation will be manipulated.

Other: Stimulus properties: task-defining feature

Interventions

The feature used to determine which stimulus feature to attend to will be varied across trials using a letter cue (M = motion-attend, C = color-attend, F = fixation-attend)

Manipulations of task demands (Expt 2.1)

Eligibility Criteria

Age18 Years - 55 Years
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64)

You may qualify if:

  • between 18 and 55 years of age
  • normal or corrected-to-normal vision

You may not qualify if:

  • neurological disease based on self-report
  • implanted medical devices (e.g., cardiac pacemaker; metallic aneurism clip)
  • non-removable metallic piercings
  • metal fragments in the body (e.g., from welding)
  • pregnant and have a chance of being pregnant (if female)
  • history of claustrophobia
  • history of hearing loss/damage

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

University of California, Santa Barbara

Santa Barbara, California, 93117, United States

Location

Related Publications (17)

  • Mackey WE, Winawer J, Curtis CE. Visual field map clusters in human frontoparietal cortex. Elife. 2017 Jun 19;6:e22974. doi: 10.7554/eLife.22974.

    PMID: 28628004BACKGROUND
  • Hallenbeck GE, Sprague TC, Rahmati M, Sreenivasan KK, Curtis CE. Working memory representations in visual cortex mediate distraction effects. Nat Commun. 2021 Aug 5;12(1):4714. doi: 10.1038/s41467-021-24973-1.

    PMID: 34354071BACKGROUND
  • Sprague TC, Itthipuripat S, Vo VA, Serences JT. Dissociable signatures of visual salience and behavioral relevance across attentional priority maps in human cortex. J Neurophysiol. 2018 Jun 1;119(6):2153-2165. doi: 10.1152/jn.00059.2018. Epub 2018 Feb 28.

    PMID: 29488841BACKGROUND
  • Sprague TC, Adam KCS, Foster JJ, Rahmati M, Sutterer DW, Vo VA. Inverted Encoding Models Assay Population-Level Stimulus Representations, Not Single-Unit Neural Tuning. eNeuro. 2018 Jun 5;5(3):ENEURO.0098-18.2018. doi: 10.1523/ENEURO.0098-18.2018. eCollection 2018 May-Jun. No abstract available.

    PMID: 29876523BACKGROUND
  • Sprague TC, Boynton GM, Serences JT. The Importance of Considering Model Choices When Interpreting Results in Computational Neuroimaging. eNeuro. 2019 Dec 20;6(6):ENEURO.0196-19.2019. doi: 10.1523/ENEURO.0196-19.2019. Print 2019 Nov/Dec.

    PMID: 31772033BACKGROUND
  • Laumann TO, Gordon EM, Adeyemo B, Snyder AZ, Joo SJ, Chen MY, Gilmore AW, McDermott KB, Nelson SM, Dosenbach NU, Schlaggar BL, Mumford JA, Poldrack RA, Petersen SE. Functional System and Areal Organization of a Highly Sampled Individual Human Brain. Neuron. 2015 Aug 5;87(3):657-70. doi: 10.1016/j.neuron.2015.06.037. Epub 2015 Jul 23.

    PMID: 26212711BACKGROUND
  • Allen EJ, St-Yves G, Wu Y, Breedlove JL, Prince JS, Dowdle LT, Nau M, Caron B, Pestilli F, Charest I, Hutchinson JB, Naselaris T, Kay K. A massive 7T fMRI dataset to bridge cognitive neuroscience and artificial intelligence. Nat Neurosci. 2022 Jan;25(1):116-126. doi: 10.1038/s41593-021-00962-x. Epub 2021 Dec 16.

    PMID: 34916659BACKGROUND
  • Fedorenko E. The early origins and the growing popularity of the individual-subject analytic approach in human neuroscience. Current Opinion in Behavioral Sciences. 2021; 40:105-112.

    BACKGROUND
  • Naselaris T, Allen E, Kay K. Extensive sampling for complete models of individual brains. Current Opinion in Behavioral Sciences. 2021; 40:45-51.

    BACKGROUND
  • Poldrack RA. Diving into the deep end: a personal reflection on the MyConnectome study. Current Opinion in Behavioral Sciences. 2021; 40:1-4.

    BACKGROUND
  • Pritschet L, Taylor CM, Santander T, Jacobs EG. Applying dense-sampling methods to reveal dynamic endocrine modulation of the nervous system. Curr Opin Behav Sci. 2021 Aug;40:72-78. doi: 10.1016/j.cobeha.2021.01.012. Epub 2021 Feb 25.

    PMID: 35369044BACKGROUND
  • Gratton C, Nelson SM, Gordon EM. Brain-behavior correlations: Two paths toward reliability. Neuron. 2022 May 4;110(9):1446-1449. doi: 10.1016/j.neuron.2022.04.018.

    PMID: 35512638BACKGROUND
  • Smith PL, Little DR. Small is beautiful: In defense of the small-N design. Psychon Bull Rev. 2018 Dec;25(6):2083-2101. doi: 10.3758/s13423-018-1451-8.

    PMID: 29557067BACKGROUND
  • Sprague TC, Serences JT. Attention modulates spatial priority maps in the human occipital, parietal and frontal cortices. Nat Neurosci. 2013 Dec;16(12):1879-87. doi: 10.1038/nn.3574. Epub 2013 Nov 10.

    PMID: 24212672BACKGROUND
  • Itthipuripat S, Vo VA, Sprague TC, Serences JT. Value-driven attentional capture enhances distractor representations in early visual cortex. PLoS Biol. 2019 Aug 9;17(8):e3000186. doi: 10.1371/journal.pbio.3000186. eCollection 2019 Aug.

    PMID: 31398186BACKGROUND
  • Poltoratski S, Tong F. Resolving the Spatial Profile of Figure Enhancement in Human V1 through Population Receptive Field Modeling. J Neurosci. 2020 Apr 15;40(16):3292-3303. doi: 10.1523/JNEUROSCI.2377-19.2020. Epub 2020 Mar 5.

    PMID: 32139585BACKGROUND
  • Poltoratski S, Ling S, McCormack D, Tong F. Characterizing the effects of feature salience and top-down attention in the early visual system. J Neurophysiol. 2017 Jul 1;118(1):564-573. doi: 10.1152/jn.00924.2016. Epub 2017 Apr 5.

    PMID: 28381491BACKGROUND

Study Officials

  • Tommy C Sprague

    University of California, Santa Barbara

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Masking Details
Participants will typically be unaware of the conditions presented, though because these involve manipulations of stimuli or task demands, they may be aware of the manipulation. This is not expected to impact the primary outcome measures (e.g., BOLD signal activation patterns).
Purpose
BASIC SCIENCE
Intervention Model
SINGLE GROUP
Model Details: This is a basic science study in which all participants will participate in all task conditions within each experiment (repeated-measures design).
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

February 16, 2024

First Posted

February 28, 2024

Study Start

April 1, 2024

Primary Completion

December 31, 2024

Study Completion

June 30, 2025

Last Updated

August 21, 2024

Record last verified: 2024-08

Data Sharing

IPD Sharing
Will share

Processed fMRI and raw behavioral data will be shared with researchers immediately upon publication

Shared Documents
STUDY PROTOCOL, SAP, ICF, ANALYTIC CODE
Time Frame
Data will be available indefinitely beginning with publication of results
Access Criteria
Processed fMRI data and raw behavioral/eyetracking data will be publicly available on the lab's Open Science Framework page (https://osf.io/ufjzl/), and analysis code will be available on GitHub (an online tool for storing and managing code; github.com/SpragueLab). Raw, unprocessed fMRI data will be made available upon justifiable request from qualified researchers
More information

Locations