InformationSeekingMesolimbicEngagementStudy2

Temple University

Status: Enrolling

Conditions: Motivation

Treatments: Behavioral: Task Instructions

Study type: Interventional

Funder types: Other

Identifiers

NCT06257433

R01DA055259 (U.S. NIH Grant/Contract)

R01DA055259-2

Details and patient eligibility

About

Participants will complete a treasure task during neuroimaging where they have to learn which keys open a treasure chest, and then they are tested on the contents of the treasure chest.

Full description

Study 2 will use a treasure task (employed in C.2.1.1), in which participants select amongst 3 keys to learn which feature of keys unlocks the treasure chest, revealing a trial unique object image (Fig. 8b). On each encoding trial participants view three multi-featural keys and a treasure chest. Each key varies on three dimensions: color (red, blue, yellow), shape of the handle (square, circle, triangle), and number of ridges (one, two, three). On each trial, all 9 dimensions of the keys are represented, but the dimensions represented on each key are randomized across trials. During hypothesis testing runs, participants are instructed to find the feature of a key that opens the treasure chest to reveal a trial-unique image. Critically, there is one target feature of a key that deterministically opens the treasure chest. The target feature of the key randomly changes after participants successfully open the chest 4 consecutive times. This design manipulates goal-oriented exploration by allowing participants to resolve uncertainty until they identify the target feature of the key. Uncertainty resolution is the greatest after the target features switches and incrementally reduces via individuals' active hypothesis testing. During control runs, participants will be instructed to select specific keys, and key selection and outcomes will be yolked to prior hypothesis testing runs. Participants will complete 3 runs of hypothesis testing runs and 3 control runs. Trial number for each run is determined by participant behavior, in that hypothesis testing runs end when participants complete 4 rule switches (~30 trials). Encoding is incidental in this task. Following encoding, participants will complete an immediate and delayed item memory test. On each trial, participants will view objects from the hypothesis testing and control conditions as well as new foil objects. Memory will be tested for half the stimuli immediately and at a 24-hour delay. These memory measures will be related to uncertainty resolution estimated by reinforcement learning, to determine how prior knowledge during information seeking has subsequent effects on memory.

Enrollment: 80 estimated patients

Sex: All

Ages: 18 to 45 years old

Volunteers: Accepts Healthy Volunteers

Inclusion criteria

• 20/40 far acuity (either corrected or uncorrected)
• In good medical health

Exclusion criteria

• History of head injury
• History of illness with Central Nervous Systems implications
• On Medications that Affect blood flow response and alertness
• Consumption of smoking and/or coffee 30 minutes prior to laboratory testing
• Placement of a device contraindicated for magnetic resonance imaging including cardia pacemaker, aneurysm clip, cochlear implants, pregnancy, intra-uterine device, shrapnel, metal fragments in the eyes, neurostimulators
• Weight > 250lbs
• Claustrophobia

Trial design

Primary purpose: Basic Science

Allocation: N/A

Interventional model: Single Group Assignment

Masking: None (Open label)

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80 participants in 1 patient group

Motivation

Experimental group

Description:

Trials in which participants are motivated by hypothesis testing or not.

Treatment:

Behavioral: Task Instructions