Testing and Calibration of Non-Invasive Optical Imaging Technology for Functional Brain Imaging

Not Applicable

Completed

Conditions: Cognition

Interventions: Behavioral: Behavioral measures
Device: fNIRS Devices & Application
Other: Physiological measures

Registration Number: NCT01212029

Lead Sponsor: Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)

Brief Summary: Background:

- Non-invasive functional near infrared (fNIR) imaging techniques use infrared light to detect changes in blood volume and oxygen levels during brain activity. fNIR is being studied as a possible way to examine the brain activity of individuals who are unable to undergo standard brain function imaging techniques (such as functional magnetic resonance imaging, or fMRI). For instance, war veterans who have iron shrapnel in the body are not able to have fMRI scans, and very young children or children with autism and related disorders are often not able or willing to cooperate long enough in the MRI environment to allow full imaging studies to take place. Researchers are interested in comparing the results of fNIR and fMRI performed on healthy volunteers to determine if fNIR produces similarly accurate results.

Objectives:

- To examine the capabilities of non-invasive functional near infrared imaging techniques on healthy volunteers and compare the results with the existing outcomes of functional magnetic resonance imaging.

Eligibility:

- Healthy volunteers at least 18 years of age.

Design:

* Participants will have one study visit. Depending on the complexity of the task, the whole exam will take between 5 minutes and 1 hour to perform.

* Participants will be asked to sit as still as possible while wearing a headband that includes light sources and detectors (the fNIR device).

* Participants will be asked to perform a set of tasks (e.g., reading sentences or counting numbers in one s head). Data will be collected during these experiments.

Detailed Description: Objective: to a) cross-validate our near infrared spectroscopy (NIRS) imaging system with existing functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) data, and b) to investigate any significant technical issues associated with optode placement and motion artifacts, and to explore techniques that will potentially improve the feasibility and reliability of the system according to the needs of the population for whom existing imaging systems are unsuitable.

Study population: 250 healthy volunteers

Design: The study will look for correlations between NIRS signal changes in healthy subjects when performing functional tasks, and existing fMRI data.

Outcome Measures: graded changes in blood flow and oxygen, measured with NIRS, in response to different functional tasks.

Recruitment & Eligibility

Status: COMPLETED

Sex: All

Target Recruitment: 126

Inclusion Criteria

Not provided

Exclusion Criteria

Not provided

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
1/All Subjects	Behavioral measures	Imaging studies related to functional brain activation
1/All Subjects	fNIRS Devices & Application	Imaging studies related to functional brain activation
1/All Subjects	Physiological measures	Imaging studies related to functional brain activation

Primary Outcome Measures

Name	Time	Method
Relationship Between Prefrontal Cortex Activation and Respiratory Sinus Arrhythmia	During the assessment	Prefrontal cortex (PFC) activation is measured in term of change in oxyhemoglobin (O2Hb) using a functional Near-Infrared Spectroscopy (fNIRS) system at a person forehead. Respiratory Sinus Arrhythmia (RSA) is the variation of heart beat in response to breathing. It is calculated as changes in the lengths of interbeat interval as a result of breathing using root mean square successive difference (RMSSD). The relationship between activation of PFC and RSA is quantified as a linear regression coefficient, which represents the estimated average change in O2Hb concentration associated with a 1 unit increase in RMSSD in heartrate interbeat interval length.
Mean Change in Oxyhemoblobin Concentration in Left Dorsolateral Prefrontal Cortex Region After Impersonal Moral Judgement Dilemma	During the assessment	Moral judgment (MJ) is the process of evaluating what is right or wrong based on social norms. The classic Trolley Dilemma describes an impersonal MJ scenario in which a trolley is hurtling toward five workers on the track. One option presented is to flip a switch to divert the course of the trolley, which would result in the trolley hurtling toward one person on the opposite side of the track, killing this one person. The other is to do nothing and allow the five workers to die. Dorsolateral prefrontal cortex (DL-PFC) is responsible for utilitarian (logical) judgments that are thought to engage more cognitive processes and fewer emotional processes. Oxyhemoglobin (O2Hb) is measured using a functional Near-Infrared Spectroscopy (fNIRS) at prefrontal cortex.

Secondary Outcome Measures

Name	Time	Method
Number of Participants With Significant Issues Associated With NIRS	During the assessment	Assess any significant issues associated with NIRS optode placement and evaluate the effect of subject motion on data collection, quality, and noise. Data from participants with significant issues, which either due to NIRS optode placement or subject motion, data quality, and noise, are removed from further analysis.
Number of Participants With High Performance But Low Prefrontal Cortex Activation	During the assessment	High performance group include people with accuracy score greater than 90% during an n-back task.