Task-less optical mapping of brain function using resting state functional connectivity

Abstract

A method for utilizing an optical system for taskless mapping of brain function includes determining a time series of dynamic light measurements for a plurality of spatially distributed source-detector pairs, receiving the dynamic light measurements over a period of time using the source-detector pairs without dependence on either a task or a change in physiological condition, generating a plurality of temporal correlations between regions of a brain for the light measurements based on the time series of the spatially distributed source-detector pairs and the received dynamic light measurements, producing at least one map of a respective strength of each of a plurality of temporal correlations, producing overlapping source-detector pairs measurements using diffuse optical tomography (DOT) geometries, reconstructing data representative of the dynamic light measurements into an image space using at least one DOT algorithm, and co-registering DOT voxel images obtained by the reconstruction to anatomical information.

What is claimed is: 
     
         1 . A method for utilizing an optical system including a plurality of spatially distributed source-detector pairs for taskless mapping of brain function, the method comprising:
 determining a time series of dynamic light measurements for a plurality of spatially distributed source-detector pairs;   receiving the dynamic light measurements over a period of time using the source-detector pairs without dependence on either a task or a change in physiological condition;   generating a plurality of temporal correlations between regions of a brain for the light measurements based on the time series of the spatially distributed source-detector pairs and the received dynamic light measurements;   producing at least one map of a respective strength of each of a plurality of temporal correlations;   producing overlapping source-detector pairs measurements using diffuse optical tomography (DOT) geometries;   reconstructing data representative of the dynamic light measurements into an image space using at least one DOT algorithm; and   co-registering DOT voxel images obtained by the reconstruction to anatomical information.   
     
     
         2 . The method of  claim 1 , wherein co-registering DOT voxel images obtained by the reconstruction to anatomical information comprises co-registering DOT voxel images obtained by the reconstruction to anatomical information obtained using magnetic resonance imaging (MRI). 
     
     
         3 . The method of  claim 2 , further comprising obtaining the anatomical information using MRI. 
     
     
         4 . The method of  claim 1 , wherein co-registering DOT voxel images obtained by the reconstruction to anatomical information comprises co-registering DOT voxel images obtained by the reconstruction to anatomical information based on geometric models with affine transformed spheres to approximate head shapes. 
     
     
         5 . The method of  claim 1 , wherein co-registering DOT voxel images obtained by the reconstruction to anatomical information comprises co-registering DOT voxel images obtained by the reconstruction to anatomical information from an atlas-based head model. 
     
     
         6 . The method of  claim 1 , wherein receiving the dynamic light measurements comprises recording fluctuations in one of light absorption, scattering fluorescence, and coherence optical contrasts. 
     
     
         7 . The method of  claim 6 , wherein receiving the dynamic light measurements further comprises receiving the dynamic light measurements one of invasively and non-invasively. 
     
     
         8 . The method of  claim 7 , wherein receiving the dynamic light measurements further comprises receiving one of time resolved measurements, frequency domain measurements, and continuous wave measurements. 
     
     
         9 . The method of  claim 1 , wherein receiving the dynamic light measurements comprises receiving the dynamic light measurements using planar reflectance geometry. 
     
     
         10 . The method of  claim 1 , wherein receiving the dynamic light measurements comprises receiving the dynamic light measurements using one of a raster-scanning source-detector pair and a plurality of discrete spatially distributed independent source-detector pairs. 
     
     
         10 . The method of  claim 1 , further comprising obtaining a cortical surface image and mapping DOT voxel images obtained by the reconstruction onto the cortical surface image. 
     
     
         11 . The method of  claim 1 , further comprising generating the plurality of temporal correlations using a correlation analysis that is interpreted as a map of functional connections. 
     
     
         12 . The method of  claim 11 , further comprising removing extraneous global correlation structures prior to mapping the functional connections. 
     
     
         13 . The method of  claim 12 , wherein removing extraneous global correlation structures comprises removing the extraneous global correlation structures using one of averaged subsets of the measurements obtained by the plurality of source-detector pairs and regions of interest within an image. 
     
     
         14 . The method of  claim 13 , wherein removing global correlation structures comprises removing the extraneous global correlation structures using one of physiological monitoring and signals derived from alternative imaging modalities. 
     
     
         15 . The method of  claim 1 , further comprising generating the plurality of temporal correlations using a correlation analysis based on a plurality of seed regions. 
     
     
         16 . The method of  claim 15 , further comprising performing the correlation analysis using a comprehensive search of a plurality of voxels as seed regions, and ranking the correlated seed regions. 
     
     
         17 . The method of  claim 1 , further comprising generating the plurality of temporal correlations using a data-driven correlation analysis using one of a principal components analysis and an independent component analysis. 
     
     
         18 . The method of  claim 1 , further comprising combining attenuation data and measurements into at least one of hemoglobin concentrations and scattering contrasts. 
     
     
         19 . An optical system for taskless mapping brain function, the system comprising:
 a plurality of spatially distributed source-detector pairs, the source-detector pairs configured to receive dynamic light measurements over a period of time; and   a computer coupled to a display and to the plurality of spatially distributed source-detector pairs, the computer configured to:
 determine a time series of dynamic light measurements for the plurality of spatially distributed source-detector pairs; 
 receive the dynamic light measurements over a period of time using the spatially distributed source-detector pairs without dependence on either a task or a change in physiological condition; 
 generate a plurality of temporal correlations between regions of a brain for the light measurements based on the time series of the spatially distributed source-detector pairs and the received dynamic light measurements; 
 produce at least one map of a respective strength of each of a plurality of temporal correlations; 
 produce overlapping source-detector pairs measurements using diffuse optical tomography (DOT) geometries; 
 reconstruct data representative of the dynamic light measurements into an image space using at least one DOT algorithm; and 
 co-register DOT voxel images obtained by the reconstruction to anatomical information, wherein the anatomical information is one of anatomical information obtained using magnetic resonance imaging (MRI), anatomical information based on geometric models with affine transformed spheres to approximate head shapes, and anatomical information from an atlas-based head model. 
   
     
     
         20 . A computer program embodied on a non-transitory computer readable medium for taskless mapping of brain function using an optical system including a plurality of spatially distributed source-detector pairs, the computer program comprising at least one code segment that configures a processor to:
 determine a time series of dynamic light measurements for the plurality of spatially distributed source-detector pairs;   receive the dynamic light measurements over a period of time using the spatially distributed source-detector pairs without dependence on either a task or a change in physiological condition;   generate a plurality of temporal correlations between regions of a brain for the light measurements based on the time series of the spatially distributed source-detector pairs and the received dynamic light measurements;   produce at least one map of a respective strength of each of a plurality of temporal correlations;   produce overlapping source-detector pairs measurements using diffuse optical tomography (DOT) geometries;   reconstruct data representative of the dynamic light measurements into an image space using at least one DOT algorithm; and   co-register DOT voxel images obtained by the reconstruction to anatomical information, wherein the anatomical information is one of anatomical information obtained using magnetic resonance imaging (MRI), anatomical information based on geometric models with affine transformed spheres to approximate head shapes, and anatomical information from an atlas-based head model.