Neuroplasticity in an Extended Amygdala Network as a Target Mechanism for Attention Bias Modification Outcome

NCT ID: NCT03092609

Last Updated: 2022-01-12

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 119 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2017-12-15
• Study Completion Date: 2020-03-14

Brief Summary

Anxiety disorders are one of the most common psychological disorders. Underlying anxiety is an increased attentional bias to threat, which has been identified as a causal contributor in the development of anxiety. Given this causal relationship, attention bias modification was introduced as a treatment option where anxiety is reduced by training individuals to direct their attention away from threat and thereby decreasing anxiety. Over a decade of research using this approach, called attention bias modification (ABM), suggests that overall the approach is effective in reducing anxiety. Although ABM appears to be a very promising treatment option for anxiety, there are several factors limiting the effectiveness of ABM. These include the recognition of individual-level needs and a known underlying mechanism of action by which ABM is effective. Neuroimaging evidence suggests that attentional bias to visual threat is associated with a network of brain regions including the amygdala, anterior cingulate cortex, and visual cortex. In human participants, experience-dependent neuroplasticity is visible in voxel-based morphometry based measures of gray matter volume following training. Recently, voxel-based morphometry measures of gray matter volume have been linked to dendritic spine density-a known cellular mechanism for learning-related neuroplasticity. Thus, voxel-based morphometry measures are ideally suited to measure learning-related neuroplasticity following attention bias modification. In this proposal participants' level of attentional bias, anxiety, and gray matter volume will be measured before and after completing six weeks of attention bias modification training (N = 50) or attention control training (N= 50). The proposal aims to (1) establish that pre-treatment bias predicts variability in gray matter volume in the extended amygdala and anterior cingulate cortex, (2) assess the extent to which reduced extended amygdala and anterior cingulate cortex gray matter volume following ABM underlies reductions in attentional bias and anxiety, and (3) Establish pre-treatment bias as a predictor of successful ABM as measured by reduced bias, reduced anxiety, and reduced gray matter volume in the extended amygdala and anterior cingulate cortex. Consistent with the objectives of the AREA grant and NIMH's focus on identifying and validating new targets for treatment development that underlie disease mechanisms, the current proposal plans to involve students at a rural primarily undergraduate university in a research project aimed at establishing neuroplasticity in the extended amygdala and anterior cingulate cortex as a target mechanism for ABM training outcome, which could be used to objectively track training-related outcomes in anxiety treatment.

Conditions

Anxiety

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: TREATMENT
• Blinding Strategy: DOUBLE

Study Groups

Attention Bias Modification

Group Type: EXPERIMENTAL

Attention Bias Modification

Intervention Type: BEHAVIORAL

Attention bias modification (ABM) sessions will consist of a modified dot-probe task that only contains incongruent trials (i.e., target-dot - neutral stimulus 100% pairing).

Attention Control

Group Type: ACTIVE_COMPARATOR

Attention Control

Intervention Type: BEHAVIORAL

Attention control (AC) sessions, will consist of a standard dot-probe task (i.e., target-dot - neutral/threat stimulus 50% pairing). Thus, for AC participants, bias should remain the same, while ABM participants should show a reduced bias to threat.

Interventions

Attention Bias Modification

Attention bias modification (ABM) sessions will consist of a modified dot-probe task that only contains incongruent trials (i.e., target-dot - neutral stimulus 100% pairing).

Intervention Type: BEHAVIORAL

Attention Control

Attention control (AC) sessions, will consist of a standard dot-probe task (i.e., target-dot - neutral/threat stimulus 50% pairing). Thus, for AC participants, bias should remain the same, while ABM participants should show a reduced bias to threat.

Intervention Type: BEHAVIORAL

Eligibility Criteria

Inclusion Criteria

• Handedness (right handed)
• Normal Vision
• High Anxiety
• Preexisting Attentional Bias

Exclusion Criteria

• No MRI contraindications
• No History of Head Injury
• No Neurological History
• Psychological History
• Limited Recreational Drug Use, No Abuse
• Limited Prescription Drug Use, No Abuse
• No Claustrophobia
• Not Pregnant

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 37 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

National Institute of Mental Health (NIMH)

NIH

Sponsor Role: collaborator

Northern Michigan University

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Joshua M Carlson, PhD

Role: PRINCIPAL_INVESTIGATOR

Northern Michigan University

Locations

Northern Michigan University

Marquette, Michigan, United States

Countries

United States

References

Carlson JM, Fang L, Koster EHW, Andrzejewski JA, Gilbertson H, Elwell KA, Zuidema TR. Neuroplastic changes in anterior cingulate cortex gray matter volume and functional connectivity following attention bias modification in high trait anxious individuals. Biol Psychol. 2022 Jul;172:108353. doi: 10.1016/j.biopsycho.2022.108353. Epub 2022 May 13.

Reference Type: DERIVED

PMID: 35569575 (View on PubMed)

Carlson JM, Fang L. Attentional bias to threat and gray matter volume morphology in high anxious individuals. Cogn Affect Behav Neurosci. 2022 Jun;22(3):600-609. doi: 10.3758/s13415-021-00968-9. Epub 2021 Nov 9.

Reference Type: DERIVED

PMID: 34755317 (View on PubMed)

Other Identifiers

R15MH110951

Identifier Type: NIH

Identifier Source: secondary_id

View Link

HS13-555

Identifier Type: -

Identifier Source: org_study_id