Brain Imaging (fNIRS) in Healthy InfantsC. Butler, N. Malek, R.Nishiyori, S. Meehan

Developmental Neuromotor Control Lab, School of Kinesiology University of Michigan

It is difficult to track any neuro-progression in an infants brain. Many behavioral development studies have been successful in infants, but cognitive development still lacks fundamental data. To learn more about these disabilities, we must first understand a healthy infant’s brain. Functional near-infrared spectroscopy (fNIRS) has become the optimal method for making the same types of observations in infants that we make in adults. FNIRS measures the oxyhemoglobin and deoxyhemoglobin levels in the blood of the brain. By measuring these levels in the brain, we could see where there was neural activity. Using this, we can see how the infant brain develops. While motor development in an infant starts immediately after birth, grasping and walking come a little later in the infants growth period.

INTRODUCTION

Using the data obtained from a healthy infants brain, we will be able to compare the brains of infants with disabilities. To learn more about these disabilities, we first had to understand a healthy infant’s brain. We studied the development of healthy infant brains to see how they develop.

PURPOSE

METHODParticipants: 8 healthy male and female (4 Female), Older: ~52.5 weeks, Younger: ~26.07 weeksAll participants performed 10 + reaching and stepping tasks with 30 seconds of rest after each trial.Reaching (FIG 2):• Toys presented at mid-line and within reach (FIG

1)Stepping (FIG 3):• Held above a moving treadmill to prompt steps.

Figure 1: Toys used for reaching

FNIRS Measurements(TechEn Inc., Milford, MA)• Headgear centered at Cz, extends to C3 and C4 (FIG 4)• 12 channels (4 emitters, 6 detectors) (FIG 5, 6)• Measures the changes in oxygenated hemoglobin

(HbO) and deoxygenated hemoglobin (HbR) as infants perform tasks (FIG 7).

We were able to use fNIRS to detect changes in brain activity as infants performed functional motor skills. As infants grow, they become better and more efficient at performing these activities. There was more defined channel activity in the younger participants than the older participants for both tasks. As the participants get older, they are more familiar with the task. For future analysis, we hope to look at the pre frontal cortex to see how focus changes after a task is familiar to infants. We also hope to study infants with disabilities in order to recognize the discrepancies in their brain development , so their motor cortex development can improve more efficiently.

Video clips are behavior coded to identify tasks of interest. These events are then aligned with the fNIRS data using preprocessing software (Homer2). We then identified which channels were active using a t-test (p < 0.05) during each activity.

DISCUSSION

Figure 3: Infant steppingFigure 2: Infant reaching

Figure 4: Coordinates headgear covers

Figure 6: Channel positions

Figure 5: Placement of emitter (red) and detector

(blue) optodes

Figure 7: Measurement of change in light

RESULTS