Title :
4D Functional Imaging in the Freely Moving Rat
Author :
Holzer, Matthew ; Schmitz, Christoph ; Pei, Yaling ; Graber, Harry ; Abdul, Rehman-Ansari ; Barry, Jeremy ; Muller, Robert ; Barbour, Randall
Author_Institution :
Dept. of Physiol. & Pharmacology, State Univ. of New York, Buffalo, NY
fDate :
Aug. 30 2006-Sept. 3 2006
Abstract :
We describe a two-frequency diffuse optical tomographic (DOT) imaging and EEG recording system suitable for the study of real-time hemodynamic and neural activities in freely moving rats. The system uses a bundle of 16 optical fibers that both deliver light and capture its reemission. This bundle runs in parallel with a cable carrying EEG signals from 16 microelectrodes. Both data collection arrays terminate in a precision-machined cap that is surgically attached to the skull. Free movement is enabled by suspending the cables with an elastic cord. Rats are also tracked with a video system so their behavior can be compared to hemodynamic and neural activity. Optical measurements are done with 760 and 830 nm laser diodes using a time-multiplexed, frequency-encoded illumination scheme at a source-switching speed of 68 Hz. EEG, optical and video data are all timestamped with the same clock, ensuring information synchrony. Automated optical system set-up and control is done with a LabVIEW interface that allows on-the-fly adjustment of gain, data integrity checks and system calibration, among other functionalities. EEG recording is done with a Neuralynx (Tucson, AZ) recording system. Collected optical data are converted to volumetric images either in real-time or offline. The integrated system includes comprehensive image formation, display and time-series analysis software suitable for processing data independently or in combination
Keywords :
bioelectric phenomena; biomedical electrodes; biomedical optical imaging; computerised instrumentation; data integrity; electroencephalography; haemodynamics; laser applications in medicine; measurement by laser beam; medical image processing; microelectrodes; neurophysiology; optical fibres; optical tomography; optical tracking; 4D functional imaging; 68 Hz; 760 nm; 830 nm; EEG recording system; LabVIEW interface; automated optical system; calibration; data integrity; elastic cord; frequency-encoded illumination scheme; image formation; laser diodes; microelectrodes; neural activities; on-the-fly adjustment; optical fibers; optical measurements; real-time hemodynamic activities; source-switching speed; time-multiplexed illumination scheme; time-series analysis software; tracking; two-frequency diffuse optical tomographic imaging; video system; volumetric images; Electroencephalography; Hemodynamics; Optical fiber cables; Optical imaging; Optical recording; Rats; Real time systems; Tomography; US Department of Transportation; Video recording;
Conference_Titel :
Engineering in Medicine and Biology Society, 2006. EMBS '06. 28th Annual International Conference of the IEEE
Conference_Location :
New York, NY
Print_ISBN :
1-4244-0032-5
Electronic_ISBN :
1557-170X
DOI :
10.1109/IEMBS.2006.260037