Brain Changes in EEG and Brain Pulsatility to Novel Stimuli (Electro-PulCe) (Electro-Pulce)

Modifications Electrophysiologiques et de la Pulsatilité Cérébrale à la détection de Stimuli Nouveaux (Electro-PulCe)

The oddball paradigm is one of the most widely used methods of brain exploration for the study of attentional processes. It allows the measurement, by means of an Electro-Enchephalogram (EEG), of evoked potentials reflecting the electrophysiological reactivity to the detection of novel stimuli within a stream of standard stimuli.

Other studies have recently suggested that, in addition to neuronal activation, certain other physiological processes related to cerebrovascular reactivity, such as the Brain Tissue Pulsatility (BTP), could also be sensitive to various cognitive processes and in particular to attentional processes.

In one of the latest studies published in collaboration with our group, it was shown that the amplitude of the electrophysiological response classically associated with attentional activity (P300 wave) was significantly correlated with the amplitude of BTP, suggesting the involvement of cerebrovascular processes in attentional functions. Nevertheless, in this study, the two methods of EEG and Tissue Pulsatility Imaging (TPI) were not synchronized, since TPI was performed at rest and not during the oddball task itself, and to date no study has sought to couple the methods of EEG and ultrasound TPI in an oddball paradigm, for a simultaneous characterization of neuronal and cerebrovascular responsiveness during attentional processes.

The general objective of this study will be to evaluate changes in BTP during the detection of novel stimuli in an oddball task in healthy volunteers, in which the two methods of TPI and EEG will be coupled and synchronized.

Study Overview

• Status: Completed
• Conditions: Healthy Volunteers
• Intervention / Treatment: Other: Registration; Other: Auditive oddball task

Detailed Description

The oddball paradigm is one of the most widely used methods of brain exploration for the study of attentional processes. It allows the measurement, by means of an Electro-Enchephalogram (EEG), of evoked potentials reflecting the electrophysiological reactivity to the detection of novel stimuli within a stream of standard stimuli. Numerous studies have thus used the oddball paradigm to identify the neuronal reactivity involved in attentional orientation towards target stimuli.

Other studies have recently suggested that, in addition to neuronal activation, certain other physiological processes related to cerebrovascular reactivity, such as the Brain Tissue Pulsatility (BTP), could also be sensitive to various cognitive processes and in particular to attentional processes. Ultrasound measurement of BTP is made possible by recent advances in both the development of ultrasound equipment and ultrasound signal processing. Our team and others have validated the measurement of BTP by ultrasound (Tissue Pulsatility Imaging - TPI) in healthy volunteers and clinical populations, and our results suggest that the mechanisms of BTP are significantly influenced by cerebrovascular physiology.

In one of the latest studies published in collaboration with our group, it was shown that the amplitude of the electrophysiological response classically associated with attentional activity (P300 wave) was significantly correlated with the amplitude of BTP, suggesting the involvement of cerebrovascular processes in attentional functions. Nevertheless, in this study, the two methods of EEG and TPI were not synchronized, since TPI was performed at rest and not during the oddball task itself, and to date no study has sought to couple the methods of EEG and ultrasound TPI in an oddball paradigm, for a simultaneous characterization of neuronal and cerebrovascular responsiveness during attentional processes.

The general objective of this study will be to evaluate changes in BTP during the detection of novel stimuli in an oddball task in healthy volunteers, in which the two methods of TPI and EEG will be coupled and synchronized.

• Study Type: Observational
• Enrollment (Actual): 25

Contacts and Locations

Study Locations

• France
  • Tours, France, 37044
    • Paedopsychiatry department, University Hospital, Tours

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 45 years (Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Non-Probability Sample

Study Population

Healthy volunteer

Description

Inclusion Criteria:

• Age between 18 and 45 years old included
• Normal hearing

Exclusion Criteria:

• History of neurologic, psychiatric or cardiologic diseases (stroke, severe head trauma, mood disorder, psychotic disorder, coronary syndrome, heart rhythm disorder, etc.)
• Treatment which could impact Brain Tissue Pulsatility (Beta-Blockers, Neuroleptics, etc...) and electrophysiological (Sedatives, Benzodiazepines, etc...) parameters.
• Legal protection measures
• Opposition to data processing

Study Plan

How is the study designed?

Design Details

• Observational Models: Other
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
Healthy volunteers	Other: Registration; Synchronized recording of BTP in ultrasound, brain activity by EEG, heart rate and blood pressure.; Other: Auditive oddball task; Presentation of an auditory sequence, comprising 'Standard' (probability of occurrence: p = 0.90) and 'Deviants' (p = 0.10, targets) sounds via loudspeakers.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Brain Tissue Pulsatility indexes	Measured by the Tissue Pulsatility Imaging technique - TPI	Baseline and during the auditive oddball task (20 minutes)

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
P300 wave	Evoked potential P300 measured by Electroencephalogram (EEG)	Baseline and during the auditive oddball task (20 minutes)
Heart Rate changes and Heart Rate Variability	Measured by electrocardiogram (ECG)	Baseline and during the auditive oddball task (20 minutes)
Arterial pressure blood	Measured by a non-invasive and continuous blood pressure bracelet.	Baseline and during the auditive oddball task (20 minutes)

Collaborators and Investigators

• Sponsor: University Hospital, Tours
• Investigators: Principal Investigator: Thomas Desmidt, Md-PhD, University Hospital, Tours

Study record dates

Study Major Dates

• Study Start (Actual): February 21, 2022
• Primary Completion (Actual): June 17, 2022
• Study Completion (Actual): June 17, 2022

Study Registration Dates

• First Submitted: January 4, 2021
• First Submitted That Met QC Criteria: January 8, 2021
• First Posted (Actual): January 11, 2021

Study Record Updates

• Last Update Posted (Actual): July 19, 2022
• Last Update Submitted That Met QC Criteria: July 18, 2022
• Last Verified: February 1, 2022

More Information

Terms related to this study

• Keywords: Electroencephalogram (EEG); Brain Tissue Pulsatility (BTP); Auditive oddball task; Tissue Pulsatility Imaging (TPI)
• Other Study ID Numbers: RIPH3-RNI19 / Electro-Pulce; IDRCB (Other Identifier: 2025-A01568-41)

Drug and device information, study documents

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