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

NCT03092609 | Completed

• 2 other identifiers: HS13-555R15MH110951
• Study Type: interventional
• Target: 119
• Locations: 1 country
• Sites: 1

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

Keywords

Attentional Bias to Threat

Outcome Measures

Primary Outcomes (1)

• Attentional Bias

  Reaction time difference to congruent and incongruent trials in the dot-probe task, which measure heightened attentional bias to threat.

  Baseline and after 6 weeks of the intervention

Secondary Outcomes (1)

• State and Trait Anxiety

  Baseline and after 6 weeks of the intervention

Other Outcomes (2)

• MRI measures of gray matter volume

  Baseline and after 6 weeks of the intervention

• MRI measures of structural and functional connectivity

  Baseline and after 6 weeks of the intervention

Study Arms (2)

Attention Bias Modification

EXPERIMENTAL

Behavioral: Attention Bias Modification

Attention Control

ACTIVE COMPARATOR

Behavioral: Attention Control

Interventions

Attention Bias Modification 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 Bias Modification

Attention Control 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.

Attention Control

Eligibility Criteria

• Age: 18 Years - 37 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

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

You may not qualify if:

• 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

Sponsors & Collaborators

• Northern Michigan University: lead
• National Institute of Mental Health (NIMH): collaborator

Study Sites (1)

Northern Michigan University

Marquette, Michigan, 49855, United States

Location

Related Publications (2)

• 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.

  PMID: 35569575 DERIVED

• 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.

  PMID: 34755317 DERIVED

MeSH Terms

Conditions

Anxiety Disorders

Condition Hierarchy (Ancestors)

Mental Disorders

Study Officials

• Joshua M Carlson, PhD

  Northern Michigan University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: DOUBLE
• Who Masked: PARTICIPANT, INVESTIGATOR
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: March 14, 2017
• First Posted: March 28, 2017
• Study Start: December 15, 2017
• Primary Completion: March 14, 2020
• Study Completion: March 14, 2020
• Last Updated: January 12, 2022

Record last verified: 2022-01

Data Sharing

• IPD Sharing: Will share

Locations

US (1)