MEG and Aphantasia (MEGAPHANTASIA)

Cerebral Oscillations During Covert Actions in Aphantasia

Covert actions are cognitive processes that involves the motor system. They include motor imagery, movement preparation, action observation or action language. They imply mental simulations, based on activations of neural networks, involved in specific operations such as perceiving or acting. These mental phenomena have intrigued and still intrigue philosophers, psychologists, and neuroscientists, as they are complex and introspective processes, which play a major role in human cognition.

To decipher similarities and differences between these types of covert actions, the investigators will focus on persons living with aphantasia, which is a neurocognitive specificity present in a small proportion of the population (5 to 8%). Aphantasia is characterized by the alteration or the absence of explicit mental representations.

This population offers an ideal testbed to disentangle the involvement of cognitive and motor processes in different forms of covert actions.

By means of magnetoencephalography, this study aims to identify and compare brain patterns and their temporal dynamics in alpha and beta bands during covert actions in two groups of healthy volunteers: aphantasics and non-aphantasics (i.e., having a non-altered imagery capacity).

If covert actions indeed share brain networks, the investigators expect aphantasics to present reduced neural and behavioral activation during the explicit (i.e., motor imagery) and implicit (movement preparation, action language and action observation) forms of covert actions.

Study Overview

• Status: Not yet recruiting
• Conditions: Aphantasia
• Intervention / Treatment: Other: MEG; Other: MRI; Behavioral: Vividness of motor imagery questionnaire - second version

• Study Type: Interventional
• Enrollment (Estimated): 40
• Phase: Not Applicable

Contacts and Locations

• Study Contact: Name: Florent LEBON, PhD; Phone Number: +336 450 445 26; Email: florent.lebon@univ-lyon1.fr

Study Locations

• France
  • Bron, France
    • CERMEP
    • Contact: Yves ROSSETTI, Professor; Phone Number: +334.78.86.50.21; Email: yves.rossetti@inserm.fr
    • Principal Investigator: Yves ROSSETTI, Professor

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

• Aged 18 to 60 years
• Willing to actively participate in the study
• Having signed an informed consent form to participate in the study

Inclusion Failure Criteria:

Identification of individuals with and without aphantasia based on responses to a questionnaire validated in the literature: Vividness of Movement Imagery Questionnaire, second version (VMIQ-2):

Scores required for inclusion in the aphantasic group

• VMIQ-2: internal visual imagery score = 55-60
• VMIQ-2: kinesthetic imagery score = 55-60

Scores required for inclusion in the non-aphantasic group

• VMIQ-2: internal visual imagery score = 20-36
• VMIQ-2: kinesthetic imagery score = 20-36

Exclusion Criteria:

• Neurological or psychiatric disorders
• History of neurological or psychiatric disorders
• Sleep disorders that may affect data variability or quality, or participant cooperation and retention, as assessed by the principal investigator or co-investigator during the inclusion interview
• Volunteers presenting standard contraindications to MEG and MRI examinations:
• Presence of incompatible metal in the body (pacemaker, implanted pump including insulin pump, neurostimulator, cochlear implants or other hearing devices, metallic prosthesis, intracerebral/surgical aneurysm clips, implantable defibrillator, ferromagnetic foreign bodies in the eyes or brain in the upper body, ventriculoperitoneal shunt valves, dental braces or steel posts in root canals, ferromagnetic foreign bodies in the upper body)
• Claustrophobia
• Pregnant or breastfeeding women
• Individuals under guardianship, curatorship, or legal protection
• Individuals deprived of liberty
• Individuals undergoing psychiatric care
• Individuals admitted to a health or social institution for reasons other than clinical research
• Individuals not affiliated with a social security system or not beneficiaries of such a system

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Basic Science
• Allocation: Non-Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Aphantasics; Healthy individuals with altered mental imagery (score between 55 and 60 for each modality at the vividness of motor imagery questionnaire - second version)	Other: MEG; Within a single session, measure of brain oscillations during four types of covert actions (motor imagery, action observation, action language and movement preparation).; Other: MRI; Anatomical MRI, performed once; Behavioral: Vividness of motor imagery questionnaire - second version; Before MEG and MRI, measure of vividness for internal visual imagery, external visual imagery and kinesthetic imagery (for 12 actions).
Active Comparator: Non-aphantasics; Healthy individuals with non-altered mental imagery (score between 20 and 36 for each modality at the vividness of motor imagery questionnaire - second version)	Other: MEG; Within a single session, measure of brain oscillations during four types of covert actions (motor imagery, action observation, action language and movement preparation).; Other: MRI; Anatomical MRI, performed once; Behavioral: Vividness of motor imagery questionnaire - second version; Before MEG and MRI, measure of vividness for internal visual imagery, external visual imagery and kinesthetic imagery (for 12 actions).

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Whole-brain power of beta band (Tesla2)	Power of beta band with whole brain analysis during each of the four covert actions (motor imagery, action observation, movement preparation and action language).	During MEG recording

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Whole-brain power of alpha band (Tesla2)	Power of alpha band with whole brain analysis during each of the four covert actions (motor imagery, action observation, movement preparation and action language).	During MEG recording
Power of beta band (Tesla2) in the primary motor cortex	Power of beta band in M1 during each of the four covert actions (motor imagery, action observation, movement preparation and action language).	During MEG recording
Power of alpha band (Tesla2) in the primary motor cortex	Power of alpha band in M1 during each of the four covert actions (motor imagery, action observation, movement preparation and action language).	During MEG recording

Collaborators and Investigators

• Sponsor: Hospices Civils de Lyon
• Investigators: Principal Investigator: Yves ROSSETTI, Professor, Hospices Civils de Lyon; Study Director: Florent LEBON, PhD, Laboratoire Interuniversitaire de Biologie de la Motricité (LIBM UR7424)

Study record dates

Study Major Dates

• Study Start (Estimated): September 1, 2026
• Primary Completion (Estimated): September 1, 2028
• Study Completion (Estimated): September 2, 2028

Study Registration Dates

• First Submitted: June 1, 2026
• First Submitted That Met QC Criteria: June 1, 2026
• First Posted (Actual): June 5, 2026

Study Record Updates

• Last Update Posted (Actual): June 5, 2026
• Last Update Submitted That Met QC Criteria: June 1, 2026
• Last Verified: June 1, 2026

More Information

Terms related to this study

• Keywords: MEG; Covert actions; Aphantasia
• Other Study ID Numbers: 69HCL26_0176; 2026-A01303-48 (Other Identifier: ID-RCB)

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No