A Novel Conditioning Approach to Counter Loneliness in Adults

This study aims to test the efficacy of a 6-session conditioning paradigm by investigating the conditioning-induced change in the socio-affective processing, loneliness, depressive symptoms, and neural correlates of lonely adults.

Study Overview

• Status: Recruiting
• Conditions: Loneliness
• Intervention / Treatment: Behavioral: Evaluative Conditioning with positive stimuli; Behavioral: Conditioning with neutral stimuli

Detailed Description

Potential participants will first be invited to complete a loneliness questionnaire online. Lonely adults will then be invited to undergo further screening. At baseline prior to the intervention training sessions, participants will first complete tests and questionnaires on loneliness, mood and depressive symptoms in addition to other socio-affective measures, and they will also be invited to receive resting-state functional MRI scanning in a 3T MRI scanner. Participants will then be allocated to one of the two intervention arms (the evaluative conditioning, and the control) in a randomized fashion with approximately half in each group. They will then complete the pre-conditioning phase of the allocated intervention arm, and their ratings on the stimuli presented during this phase will be assessed. In the conditioning phase, they will be invited to attend 6 sessions. After completing the conditioning phase, participants will be invited to complete the post- conditioning phase, providing ratings on the stimuli like the pre-conditioning phase. Immediately after, and also 3 months after, participants will be invited to complete again tests and questionnaires on loneliness, mood and depressive symptoms in addition to other socio-affective measures, and they will also be invited to receive resting-state functional MRI scanning in a 3T MRI scanner.

• Study Type: Interventional
• Enrollment (Estimated): 136
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Nichol ML Wong, PhD; Phone Number: 852-29487431; Email: nmlwong@eduhk.hk

Study Locations

• Hong Kong
  • Hong Kong, Hong Kong
    • Recruiting
    • The University of Hong Kong
    • Contact: Nichol ML Wong, PhD; Phone Number: 852-29487431; Email: nmlwong@eduhk.hk

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

• No histories of learning impairment, major psychiatric disorders or neurological disorders other than depression
• Normal intelligence
• At least primary school education

Exclusion Criteria:

• On medication or treatments within 2 weeks prior to the beginning of the study that would affect the individual's brain, cognitive and affective functions

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Evaluative conditioning group with positive stimuli; Participants will be exposed to social stimuli paired with positive stimuli across multiple sessions.	Behavioral: Evaluative Conditioning with positive stimuli; In the pre-conditioning phase, participants will be exposed to pictures that vary in their emotional (negative, positive) and social (non-social, social) content. For each picture, they are required to indicate their immediate perceived valence (between negative to positive), degree of social motivation (between none to high) on Likert-scales. In the conditioning phase, emotional social pictures will be selected and paired with non-social positive stimuli for trials in random order, for 6 sessions across 3 weeks. In the post-conditioning phase, participants will be asked to evaluate the valence of the stimuli again similar to that in pre-conditioning phase.
Active Comparator: Control group with neutral stimuli; Participants will be exposed to social stimuli paired with neutral stimuli across multiple sessions.	Behavioral: Conditioning with neutral stimuli; In the pre-conditioning phase, participants will be exposed to pictures that vary in their emotional (negative, positive) and social (non-social, social) content. For each picture, they are required to indicate their immediate perceived valence (between negative to positive), degree of social motivation (between none to high) on Likert-scales. In the conditioning phase, emotional social pictures will be selected and paired with with neutral non-social stimuli for trials in random order, for 6 sessions across 3 weeks. In the post-conditioning phase, participants will be asked to evaluate the valence of the stimuli again similar to that in pre-conditioning phase.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Self-reported loneliness	Loneliness is assessed based on the UCLA loneliness scale (Version 3), a 20-item 4-point Likert scale (score range 20 - 80) in which higher scores indicate greater degrees of loneliness.	Baseline, immediately after, and 3 months after the intervention
Implicit loneliness	Implicit loneliness will be measured by Implicit Association Test about the relative strength of association between our participants' target concept 'Self' and attribute 'Lonely'.	Baseline, immediately after, and 3 months after the intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Valence of social stimuli	For each stimuli, they are required to indicate their immediate perceived valence (between negative to positive) of the scenes on a 7-point Likert scale (1 = strongly positive, 7 = strongly negative).	Baseline, immediately after, and 3 months after the intervention
Social motivation towards social stimuli	For each stimuli, they are required to indicate their immediate perceived degree of social motivation (between none to high) of the scenes on a 7-point Likert scales (1 = no, 7 = very high).	Baseline, immediately after, and 3 months after the intervention
Loneliness-related activation patterns and connectivity in neural networks	Neural connectivity in Default Mode Network, Ventral Attention Network, Frontoparietal Network are assessed by fMRI	Baseline, immediately after, and 3 months after the intervention
Depressive symptoms	Depressive symptoms are assessed based on the Hospital Anxiety and Depression Scale, a 14-item scale assessing severity of depressive and anxiety symptom (score range 0 - 21 for both subscale), with higher scores indicating higher severity	Baseline, immediately after, and 3 months after the intervention
Daily loneliness	Daily loneliness is assessed based on a 5-minute self-report on a Likert scale	Through study completion, on average of 4 months

Collaborators and Investigators

• Sponsor: Education University of Hong Kong
• Collaborators: The University of Hong Kong
• Investigators: Principal Investigator: Nichol ML Wong, PhD, Education University of Hong Kong

Publications and helpful links

General Publications

• Wong NML, Lee TMC. Evaluating the effects of a conditioning training paradigm on loneliness, socio-affective processing, and brain connectivity: a study protocol of a two-arm randomised controlled trial. BMC Psychol. 2025 Aug 27;13(1):975. doi: 10.1186/s40359-025-03342-3.

Study record dates

Study Major Dates

• Study Start (Actual): August 19, 2025
• Primary Completion (Estimated): June 1, 2026
• Study Completion (Estimated): June 1, 2026

Study Registration Dates

• First Submitted: July 11, 2024
• First Submitted That Met QC Criteria: July 22, 2024
• First Posted (Actual): July 25, 2024

Study Record Updates

• Last Update Posted (Actual): March 2, 2026
• Last Update Submitted That Met QC Criteria: February 27, 2026
• Last Verified: February 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: E2022-2023-0082

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No