Study of the Effect of Proprioceptive Stimuli in the Stomatognathic Area on Visual Perception, With and Without Sound

NCT07051460 | Completed

• 1 other identifier: CEIm HOUB 43/2022
• Study Type: observational
• Target: 38
• Locations: 1 country
• Sites: 1

Brief Summary

The goal of this observational study is to investigate how oral proprioceptive stimuli affect visual perception and auditory-visual integration in healthy young adults. The main questions it aims to answer are:

• Can Oral Proprioceptive Stimuli (OPS) induce Visual pseudo-Scotomas (VS) in the absence of other stimuli?
• Can Oral Proprioceptive Stimuli (OPS) modulate or eliminate Visual pseudo-Scotomas (VS) induced by auditory stimuli? Researchers evaluated 38 healthy adults (aged 20-29) using the Vertical Maddox Test to detect functional visual alterations under different conditions. The study included four phases:
• Baseline assessment with no stimuli.
• Assessment with auditory stimuli alone.
• Assessment with simultaneous auditory and Oral Proprioceptive Stimuli (OPS), including tongue/lip positions (Combined Oral Stimuli) and dental pressure/traction stimuli (Dental Stimuli).
• Assessment with Oral Proprioceptive Stimuli (OPS) alone. Visual pseudo-scotomas were recorded based on participant responses. The study was approved by the local ethics committee and all participants gave informed consent.

Conditions

Proprioception; Visual Perception; Multisensory; Stomatognathic System

Keywords

Proprioception; Multisensory Integration; Trigeminal Nerve; Visual Perception; Periodontal Mechanoreceptors; Stomatognathic System

Outcome Measures

Primary Outcomes (1)

• Presence of Visual Pseudo-Scotomas (VS) under Auditory and/or Oral Proprioceptive Stimulation

  Participants were assessed for the occurrence of functional visual disturbances (pseudo-scotomas, or VS) during each phase of the protocol using the Vertical Maddox Test. Presence or absence of VS was recorded under three experimental conditions: auditory stimulation alone, combined auditory and oral proprioceptive stimulation, and oral proprioceptive stimulation alone.

  During 4-phase experimental protocol (single visit, approx. 45 minutes)

Secondary Outcomes (2)

• Elimination of Sound-Induced Visual Pseudo-Scotomas by Oral Proprioceptive Stimuli

  Day 1, during phase 3 (auditory + OPS) of the experimental protocol

• Presence of Visual Pseudo-Scotomas with Oral Proprioceptive Stimulation Alone

  Day 1, during phase 4 (OPS alone) of the experimental protocol

Study Arms (1)

Healthy adults

Healthy young adult participants (ages 20-29) underwent a 4-phase experimental protocol involving auditory and oral proprioceptive stimuli under controlled conditions, using the Vertical Maddox Test to assess transient visual changes.

Other: Baseline Condition (No Stimuli); Other: Auditory Stimulation only; Other: Auditory and Oral Proprioceptive Stimulation (OPS); Other: Oral Proprioceptive Stimulation Only (OPS)

Interventions

Baseline Condition (No Stimuli) OTHER

Participants underwent baseline evaluation using the Vertical Maddox Test with no auditory or oral proprioceptive stimulation. This phase was used to confirm the absence of spontaneous visual pseudo-scotomas and served as an internal control condition for each participant.

Also known as: Phase 1

Healthy adults

Auditory Stimulation only OTHER

Participants received bilateral auditory stimulation consisting of 500 Hz tones (500 ms duration, 50 dB) delivered through wireless headphones, without any accompanying oral stimuli. This condition was used to assess the isolated effect of sound on visual perception using the Vertical Maddox Test.

Also known as: Phase 2

Healthy adults

Auditory and Oral Proprioceptive Stimulation (OPS) OTHER

Participants received simultaneous auditory and oral proprioceptive stimuli while undergoing the Vertical Maddox Test. - Auditory: 500 Hz tones (500 ms, 50 dB) via headphones. - Oral Proprioceptive Stimuli (OPS): included Combined Oral Stimuli (e.g., tongue and lip self-administered positions) and Dental Stimuli (mechanical pressure or traction on central incisors using a calibrated probe). This condition aimed to assess whether OPS could modulate or eliminate sound-induced visual pseudo-scotomas.

Also known as: Phase 3

Healthy adults

Oral Proprioceptive Stimulation Only (OPS) OTHER

Participants received oral proprioceptive stimuli alone, without auditory input, during the Vertical Maddox Test. - Combined Oral Stimuli (COS): self-administered tongue/lip positions. - Dental Stimuli (DS): applied by the operator to central incisors. This condition was used to evaluate the independent effect of OPS on visual perception.

Healthy adults

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

The participants of the study were healthy young adults recruited among the students of the Faculty of Medicine and Health Sciences of the University of Barcelona, who did not present any of the exclusion criteria listed above.

You may not qualify if:

• General criteria:
• Treatment with psychotropic drugs
• Hearing loss in one or both ears
• Visual criteria:
• Visual acuity worse than 20/20 in one or both eyes
• Stereopsis (three-dimensional vision) less than 120 arc sec
• Vertical phoria greater than 0.75 Δ
• Strabismus operated on or not
• Ongoing optometric rehabilitation
• History of amblyopia
• Dental criteria:
• Missing one or more incisors
• Presence of conservative, prosthetic or orthodontic treatment on one or more incisors (fillings, root canal treatments, veneers, crowns, brackets, Invisalign type attachments...).

Sponsors & Collaborators

• Sophie Román Richon: lead
• Hospital Odontològic UB: collaborator

Study Sites (1)

Hospital Odontológico Universitat de Barcelona

Barcelona, Spain

Location

Related Publications (2)

• Quercia P, Pozzo T, Marino A, Guillemant AL, Cappe C, Gueugneau N. Alteration in binocular fusion modifies audiovisual integration in children. Clin Ophthalmol. 2019 Jul 4;13:1137-1145. doi: 10.2147/OPTH.S201747. eCollection 2019.

  PMID: 31308621 BACKGROUND

• Quercia P, Pozzo T, Marino A, Guillemant AL, Cappe C, Gueugneau N. Children with Dyslexia Have Altered Cross-Modal Processing Linked to Binocular Fusion. A Pilot Study. Clin Ophthalmol. 2020 Feb 13;14:437-448. doi: 10.2147/OPTH.S226690. eCollection 2020.

  PMID: 32103890 BACKGROUND

MeSH Terms

Interventions

Clinical Trials, Phase I as Topic; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic

Intervention Hierarchy (Ancestors)

Clinical Trials as Topic; Clinical Studies as Topic; Epidemiologic Study Characteristics; Epidemiologic Methods; Investigative Techniques; Health Care Evaluation Mechanisms; Quality of Health Care; Health Care Quality, Access, and Evaluation; Public Health; Environment and Public Health

Study Design

• Study Type: observational
• Observational Model: OTHER
• Time Perspective: CROSS SECTIONAL
• Target Duration: 1 Day
• Sponsor Type: OTHER
• Responsible Party: SPONSOR INVESTIGATOR
• PI Title: Associate Professor Department of Odontostomatology

Study Record Dates

• First Submitted: June 12, 2025
• First Posted: July 4, 2025
• Study Start: December 16, 2022
• Primary Completion: March 3, 2023
• Study Completion: March 3, 2023
• Last Updated: July 4, 2025

Record last verified: 2025-06

Locations

ES (1)