Oxygen Absorption in Hemoglobin and Brain Activity Measurement · Motivation zA need for non-invasively measuring cognitive function Current methods of measuring brain function include

Oxygen Absorption in Hemoglobin and Brain Activity Measurement

Quantitation of Oxygen ConcentrationShakera Guess

Advisor: Dr. Britton Chance Ph. D, Sc. D, M.D

Motivation

Current methods of lie detection– Polygraph

Breathing rate, pulse, blood pressure, perspirationAnxiety Detector

Motivation

Current methods of lie detection– fMRI

Brain mappingCurrently most favorableImmobilizationExpensive

Motivation

A need for non-invasively measuring cognitive function

Current methods of measuring brain function include positron emission tomography (PET imaging) and electroencephalography (EEG).

Background

•Near Infrared Spectroscopy (NIRS)•Many benefits

•Used in a variety of procedures

•700-900 nmLCC HbOHbOHbHbeGII )(

022αα +−=

– Absorption in body contains information about hemoglobin level changes

– Thinking = BV level changes

– Biological tissue transparent 700-900 nm

– NIRS can predict certain thought processes

Background

Project Goals

Different methods of quantitationNIRS and Cognosensor

Oxygen Absorption in Yeast

Oxygen Absorption Measurement in Yeast UsingOxygen Electrode

0

50

100

150

200

1 2 3 4 5 6 7

Time (min)

Absorption

Yeast

Water

•Results of experiment performed with Clarke Oxygen Electrode, yeast, and water.

•Electrode used to connect with the non-metallic part of a circuit

using equation

O2 + H2O + 2e- → H2O2 + 2OH-

Oxygen Absorption in Hemoglobin

Oxygen Electrode Data 7/19

0

50

100

150

200

250

0 7

14

21

28

35

42

49

56

63

70

77

Time

Intensity

Intensity•Results of oxygen absorption measurement in hemoglobin performed with Clarke Oxygen Electrode.

Oxygen (Electrode) and Hemoglobin (Brain Probe)Data Merged

-300

-200

-100

0

100

2000

27.7

50.5

53.3

61.1

88.8

117

144

Time

Intensity/Blood

Volume

Oxygen

Hemoglobin (x5)

Further Uses

Early breast cancer detection– Women under 40– High risk– Underserved population

Right Left Right Left

Further Uses

Lie detection– Many ground-

breaking studies– Changes in blood

oxygenation in cortex– Cognitive components

of deception and emotional response

– NIRS used to differentiate

Conclusions

Near Infra-Red Spectroscopy (NIRS) used to measure the change of blood volumes in the brainSimple and cheap handheld device used to non-invasively measure cognitive functionMany uses including lie detection and early breast cancer detection

Acknowledgements

SUNFEST ParticipantsDr. Britton ChanceDr. Van der Spiegel– His office, DeloresSpecial thanks to the

National Science Foundation and the University of Pennsylvania.

Thank You!

Shakera Guess