fnirs and bcis

Question 1

fnirs temp and spatial res?

Answer 1

temporal: hundreds of ms
spatial: 1 cm2, outer cortex 2-4mm

Question 2

fnirs advantages disadvantages

Answer 2

+ cheap, portable, eco valid settings, more comfortable, can measure broader range pps
+ good SNR, less issues with audio, metal, motion
+ 2 measures: Hb and OxyHb
- scattering of signal, differential attenuation by skin pigments
- locations that can be measured depends on electrode placement, limited spatial standardization, uses reference points

Question 3

how does fnirs work

Answer 3

source sends out near IR light with wavelengths 750 for Hb and 850 for HbO2. in this optical window, they have different responses, are chromophores. at the detector measured how much light is let reflected (instead of absorped). With Beer lambert law calculated how much concentration of each is. due to neurovascular coupling, active regions have BOLD response with more HbO2 during activity. now you have 2 DVs each specifying how much activated the region is under the electrodes.

Question 4

sorger expeirment

Answer 4

1. localizer run to determine which optode pair discriminates best