Meltem Izzetoglu Optical Brain Imaging Team School of Biomedical Engineering, Science & Health Systems, Drexel University Philadelphia, PA Joint Studies with Britton Chance and His Team Adult and Pediatric Applications of Optical Brain Imaging June 3 & 4, 2011 Philadelphia PA, USA Britton Chance: Life, Times, & Legacy Symposium and Workshop

Outline Early joint studies with Dr. Chance and Optical Brain Imaging team at Drexel University  Signal processing algorithm developments and various applications  First prototype pediatric system development, testing and applications Influence of the early studies in the current algorithm developments, system designs and applications  Algorithms for motion artifact removal and applications  Evolution of the pediatric system to current wireless version and applications  Evolution of the phantom model and tests conducted

Algorithm developments and applications Single trial evoked hemodynamic response extraction (Izzetoglu et al, 2005)  Anagram Protocol (a linguistic problem solving study of graded difficulty)  Model Fitting for Single Trial Hemodynamic Response Detection o Oxygenation data (Oxy) is modeled as the summation of each single trial hemodynamic functions (HF) related to stimulus: o Each hemodynamic function is represented by a gamma function : o Unknown parameters of HFs are found by minimizing the mean square error between Oxy data and the model by using least mean squares curve fitting:

Algorithm developments and applications Single trial evoked hemodynamic response extraction  Results on 14 subject Anagram data collected at Dr. Chance’s Laboratory  Oxygenation rise times follow the same pattern as the behavioral response times (Pearson’s r = 0.92).  The rise time and maximum amplitude of oxygenation increase as the difficulty level of the anagram solutions increase

Algorithm developments and applications Arithmetic and Geometric Mathematical Problem Solving Study  Higher bilateral oxygenation is observed during tasks with higher difficulty compared to control tasks with less difficulty.  fNIR findings of are inline with fMRI literature that indicates higher prefrontal cortex activation during problem solving

First prototype pediatric system development One light source (with two built in LEDs at 730 and 850nm wavelengths) two detector wired pediatric system (Alper Bozkurt, Master’s thesis,2004)

Testing on phantoms and pediatric applications Testing on liquid phantom in Dr. Chance’s Laborator y (Bozkurt et al, 2005) Pediatric Application - Hearing test (Rosen et al, 2005)  NIRS measurements were obtained for 1 minute before, during, and 1 minutes after NJ State mandated hearing screen evaluation from two healthy newborns.

Influence of the early studies in algorithm developments, system designs and applications

Evolution of Signal Processing Algorithms and Applications Motion Artifact Removal  Adaptive, Wiener and Kalman Filters (Izzetoglu et al. 2005, 2010)  ICA/PCA based algorithm used in the operating room (Kurtulus Izzetoglu, Ph.D. thesis, 2008)  S-MAR used in BCI Settings and FAA Applications (Hasan Ayaz, Ph.D. thesis, 2010)

Evolution of Signal Processing Algorithms and applications Learning Disabilities in adults and children – Dyslexia and Discalculia  Lexical Decision Task (LDT): identification of words and pseudowords  22 adults and 25 7th grade children (all regular readers)  Age-related differences are found in left DLPFC.  Ongoing studies explore: brain activation differences in adults and children with and without reading or math difficulties using fNIR technology

Evolution of the pediatric system to current wireless version with application to pediatric pain assessment Wireless pediatric system Pediatric pain assessment (Izzetoglu et al, 2010)  5 healthy term infants  2 heel-stick blood draws,  2 intra-muscular vaccination,  1 circumcision and vaccination.  Texas Instrument’s ZigBee cc2430 System-on- Chip  60 feet wireless communication in open space  30 feet wireless communication in lab environment  Battery performance of 3 continuous hours

Evolution of the phantom model Multi Layer Dynamic Liquid Phantom  adult human head model with skin, skull, CSF and brain layers  Dynamic changes in Hb and HbO2 can be established  Allows measurement from skin and brain sides  Targets can be placed within the brain layer Tests conducted  effects of superficial layers at different source detector separations  Hematoma and edema tests

Thank You ________________________________________________________ Meltem Izzetoglu 3141 Chestnut St Philadelphia PA Tel: Fax: