Near infrared spectroscopy

Table of contents

• DO NOT
• Remind the parents…
• Study Procedure
• Experimenter Responsibilities for NIRS studies
  • Preparation
  • Consent
  • Before Testing
  • Placing the cap on the participant
  • communication with parents
  • Testing
  • After Testing

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DO NOT

• BREAK FOLD OR TANGLE THE WIRES (THEY ARE OPTIC FIBRES)
• LOOK DIRECTLY AT THE INFRARED LASER

Remind the parents…

1. Do not speak to infants and remain silent in the study
2. Do not shake their legs or tap infants in the study
3. Hold infants to restrain their body movements
4. If infants try to grab the fiber or cap, try to remove their hands gently
5. Sit comfortably in the couch

Study Procedure

1. Put the cap on the participant properly
2. Click on probe set

1. If there are too many red channels, this is likely caused by sensors not touching the scalp. - Move the corresponding sensors to improve contact - Run the Auto Gain again until the key regions turn green
2. Press “Ready” button on the NIRS machine

Stop the study if infants become fussy, crying, or constantly lose attention to the screen

Experimenter Responsibilities for NIRS studies

E1: primary experimenter

E2: assistant experimenter

E3: assistant experimenter (if there is a sibling)

E1 and E2 should arrive at the lab at least 30 mins before the scheduled time.

E1 and E2 should mute cell phones during testing.

Preparation

E1:

1. Turn on NIRS machine and input participant information (ID, name, age, gender)
   1. Check the NIRS cap
   2. Fibers should not be tangled
   3. Sensors are placed in the right holders
   4. Turn on the NIRS monitor camera (make sure dial is on camera mode and press the red button to start recording)
2. Test study program
   1. Run the study program to see if everything works well
   2. Adjust the volume if necessary

E2:

• Prepare documents
  • Study tracking sheet on the study computer
  • Questionnaire, if necessary
  • Letter of Information (on iPad) Parent and Lab copies
  • Image consent form: Infant and Adult copies
  • Parking pass

1. Prepare toys for infant participants

Consent

E1:

• Debrief study content
• Explain each document
• Help parent finish the questionnaire

E2:

• Take care of infant participant

Before Testing

E1:

• Introduce the testing room
  • NIRS: machine, cap, and cable belt
  • Eye tracker (if possible)
  • Camera
  • Headphones if used
• Remind the parent to silence their cell phone

E2:

• Help parent wear cable belt

Placing the cap on the participant

E2:

• Use a toy to distract the participant’s attention
• Bring the cap over the parent’s shoulder
• Collect the NIRS cap cables with the velcro on the cable belt

E1:

• Put the NIRS cap on the participant
• Make sure the cap is on the right spot and fasten the cap

communication with parents

Testing

E1

• Turn off light
• Check channel connection
• Start program
• Start camera recording

E2

• Monitor infant’s status
• Ask parents to calm the infant if they become fussy
• Stop infants from grabbing the cap or fiber gently
• Wear parent blindfold (if necessary)

After Testing

E1:

• Debrief the study
• Check and save data on NIRS machine
• Rewind the NIRS camera
• Clean the testing room

E2:

• Clean testing room and toys
• Update testing sheet
• Input all the documents/questionnaire if applicable