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Exploring Cognitive Functions in Babies, Children & Adults with Near Infrared Spectroscopy
Published on: July 28, 2009
Test-retest reliability of functional near infrared spectroscopy in infants
Anna Blasi1, Sarah Lloyd-Fox1, Mark H Johnson1
1Birkbeck, University of London , Centre for Brain and Cognitive Development, Malet Street, London WC1E 7HX, United Kingdom.
Insights
Functional near-infrared spectroscopy (fNIRS) shows promising test-retest reliability for infant brain activation studies. This measure is particularly reliable for group analyses in developmental research.
Area of Science:
- Neuroscience
- Developmental Psychology
- Biomedical Engineering
Background:
- Functional near-infrared spectroscopy (fNIRS) is increasingly used in human developmental research.
- Test-retest reliability of fNIRS brain activation measures in infants is not well-established.
Purpose of the Study:
- To assess the test-retest reliability of fNIRS brain activation measurements in infants.
- To evaluate reliability at both individual and group levels.
Main Methods:
- Utilized longitudinal data from 13 infants participating in an fNIRS social perception study at two time points, 8.5 months apart.
- Assessed inter- and intrasession reliability using oxyhemoglobin signals.
- Measured infant compliance and sensor placement consistency between sessions.
Main Results:
- Good group-level spatial overlap (0.941) and signal reliability were observed.
- Acceptable participant-level spatial overlap (average [Formula: see text]) was found, though individual signal reliability varied.
- Infant compliance and sensor placement were consistent across sessions.
Conclusions:
- fNIRS demonstrates encouraging test-retest reliability for infant brain activation studies.
- The findings support the use of fNIRS, especially for group-based analyses in developmental neuroscience.
- Further research may refine individual-level reliability assessments.
Abstract:
There has been a rapid rise in the number of publications using functional near infrared spectroscopy (fNIRS) for human developmental research over the past decade. However test-retest reliability of this measure of brain activation in infants remains unknown. To assess this, we utilized data from a longitudinal cohort who participated in an fNIRS study on social perception at two age points. Thirteen infants had valid data from two sessions held 8.5 months apart (4 to 8 months and 12 to 16 months). Inter- and intrasession fNIRS test-retest reliability was assessed at the individual and group levels using the oxyhemoglobin ([Formula: see text]) signal. Infant compliance with the study was similar in both sessions (assessed by the proportion of time infants looked to the stimuli), and there was minimal discrepancy in sensor placement over the targeted area between sessions. At the group level, good spatial overlap of significant responses and signal reliability was seen (spatial overlap was 0.941 and average signal change within an region of interest was [Formula: see text]). At participant level, spatial overlap was acceptable ([Formula: see text] on average across infants) although signal reliability varied between participants. This first study of test-retest reliability of fNIRS in infants shows encouraging results, particularly for group-based analysis.
