Testing and Calibration of Non-Invasive Optical Imaging Technology for Functional Brain Imaging
Overview
- Phase
- Not Applicable
- Intervention
- Not specified
- Conditions
- Cognition
- Sponsor
- Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD)
- Enrollment
- 126
- Locations
- 1
- Primary Endpoint
- Relationship Between Prefrontal Cortex Activation and Respiratory Sinus Arrhythmia
- Status
- Completed
- Last Updated
- last year
Overview
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.
Investigators
Eligibility Criteria
Inclusion Criteria
- Not provided
Exclusion Criteria
- Not provided
Outcomes
Primary Outcomes
Relationship Between Prefrontal Cortex Activation and Respiratory Sinus Arrhythmia
Time Frame: 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
Time Frame: 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 Outcomes
- Number of Participants With Significant Issues Associated With NIRS(During the assessment)
- Number of Participants With High Performance But Low Prefrontal Cortex Activation(During the assessment)