Brain Networks Involved in Inner World Control

NCT07469631 | Not Yet Recruiting

• 1 other identifier: 69HCL25_0796
• Study Type: interventional
• Target: 60
• Locations: 1 country
• Sites: 2

Brief Summary

Inner speech (the "little voice" in our heads) plays a central role in our ability to perform complex cognitive tasks such as problem solving, reading, writing, thinking, and self awareness. It is estimated that at least a quarter of our lives is accompanied by inner speech, whether deliberate (mentally making a list) or more spontaneous (mind wandering). Although central to human life, its neural bases remain poorly understood. It has been recently discovered a single region in the human prefrontal cortex absent in nonhuman primates, the prefrontal operculum (PFO), which shows a pattern of functional connectivity with the rest of the brain that could give it a role in controlling inner speech. The aim of this research is to understand how the brain generates and controls inner speech using functional magnetic resonance imaging (fMRI). Dysfunctions of inner speech, especially when spontaneous and wandering, can lead to severe mental disorders (anxiety disorders, depression, verbal auditory hallucinations). It is therefore crucial to identify the role of the PFO and the networks that involve it, particularly the precuneus, in controlling inner speech across its different manifestations. The first hypothesis is that the PFO and the networks that include it play a key role in the cognitive control of inner speech in participants who experience inner speech. The second hypothesis is that the PFO is hyperactive in participants who lack inner speech (so called aphantasics), preventing the production of inner speech. To test these hypotheses, participants will complete a battery of well established questionnaires to determine whether they can produce inner speech (control participants with typical inner speech) or not (aphantasic participants). These participants will take part in an fMRI study contrasting tasks that recruit inner speech that do or do not require cognitive control. The third hypothesis is that the extent of inner speech depends on the capacity for self representation, and thus on the interaction between the PFO and the precuneus. The investigator hypothesize a positive correlation between inner speech ability and self representation capacity, associated with stronger functional connectivity between the PFO and the precuneus. The investigator predict reduced self representation in aphantasic participants. To test this, participants will complete a battery of well established questionnaires. The investigator will compute correlations between 1) behavioral performance on inner speech tasks and questionnaire scores, and 2) the network measures identified in fMRI (task activation and connectivity) and questionnaire scores.

Conditions

Neurosciences

Keywords

Prefrontal operculum; precuneus; inner language; self; imaging

Outcome Measures

Primary Outcomes (1)

• To assess the role of the prefrontal operculum (PFO) (and the brain network to which it belongs)

  MRI measurement (without contrast injection) according to the conditions of inner speech used

  at 60 days

Secondary Outcomes (2)

• To assess the relation between MRI and behavioral measures - behavioral performance

  during 60 days

• To assess the relation between MRI and behavioral measures - inner speech

  during 60 days

Study Arms (2)

Neurotypical subjects

EXPERIMENTAL

The study population will consist of healthy adult human participants, male and female, with inner speech, whose native language is French

Behavioral: Neuropsychological evaluation, questionnaires, and training on the tasks that will be performed in the MRI.; Other: MRI visits

Aphantasic subjects

EXPERIMENTAL

The study population will consist of healthy adult human participants, male and female, without inner speech, whose native language is French

Behavioral: Neuropsychological evaluation, questionnaires, and training on the tasks that will be performed in the MRI.; Other: MRI visits

Interventions

Neuropsychological evaluation, questionnaires, and training on the tasks that will be performed in the MRI. BEHAVIORAL

The neuropsychological/questionnaires evaluation is a 3 hour visit during which participants will complete a battery of neuropsychological tests and respond to questionnaires assessing their capacity for inner speech and self representation. In a second 30 minute visit, they will be trained on the tasks (inner speech tasks and control tasks) that they will perform in the MRI.

Aphantasic subjects; Neurotypical subjects

MRI visits OTHER

There will be two 2 hour MRI visits. During the first visit, participants will perform the learned task conditions designed to test the control of inner speech; during the second visit, they will perform the control conditions and an anatomical MRI will be acquired, as well as a resting state fMRI scan to study functional connectivity and a DTI scan to study structural connectivity

Aphantasic subjects; Neurotypical subjects

Eligibility Criteria

• Age: 20 Years - 45 Years
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Registered with the national Social Security system.
• Right handed.
• Native French speakers.
• Visual acuity sufficient to read stimuli (contact lenses permitted).
• Willing to follow MRI instructions and recommendations.
• Able to provide written informed consent to participate in the study.

You may not qualify if:

• History of known neurological or psychiatric disorder.
• Respiratory pathologies (in particular persistent asthma) or cardiovascular diseases.
• Speech or language disorders (aphasia, dysphasia, dysarthria, stuttering, etc.).
• Hearing impairments.
• Memory disorders.
• Cognitive impairments limiting understanding of instructions.
• Recent use of psychotropic medications. Major treatments not permitted in this research include psychotropic drugs that can alter perception, sensations, mood, consciousness, or behavior, for example:
• Antipsychotics (valproic acid, amisulpride, aripiprazole, clozapine, cyamemazine, haloperidol, loxapine, olanzapine, risperidone).
• Antidepressants (amitriptyline, citalopram, clomipramine, duloxetine, escitalopram, fluoxetine, mianserin, mirtazapine, nortriptyline, paroxetine, sertraline, venlafaxine).
• Anxiolytics.
• Minors.
• Persons deprived of liberty by judicial or administrative decision.
• Persons admitted to a health or social institution for reasons other than research.
• Adults under legal protection measures (guardianship, conservatorship).
• Persons not affiliated with a social security scheme or with a similar scheme only.

Sponsors & Collaborators

• Hospices Civils de Lyon: lead

Study Sites (2)

CRNL, IMPACT team, INSERM U1028

Bron, France

Location

Plateforme PRIMAGE, Cermep

Bron, France

Location

MeSH Terms

Interventions

Surveys and Questionnaires

Intervention Hierarchy (Ancestors)

Data Collection; Epidemiologic Methods; Investigative Techniques; Health Care Evaluation Mechanisms; Quality of Health Care; Health Care Quality, Access, and Evaluation; Public Health; Environment and Public Health

Central Study Contacts

Fadila Hadj-Bouziane

CONTACT

04 72 91 34 04; fadila.hadj-bouziane@inserm.fr

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NON RANDOMIZED
• Masking: NONE
• Purpose: BASIC SCIENCE
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: February 24, 2026
• First Posted: March 13, 2026
• Study Start: May 1, 2026
• Primary Completion (Estimated): May 1, 2028
• Study Completion (Estimated): May 1, 2028
• Last Updated: March 13, 2026

Record last verified: 2026-03

Locations

FR (2)