Gray Pixel Research Articles

Effects of beta-cypermethrin on male rat reproductive system

To study adverse effects and underlying mechanisms of beta-cypermethrin (β-cyp) on male reproductive system, the 15-day intact male adult Sprague–Dawley (SD) rats assay was used as an in vivo test. Male adult SD rats were treated by oral gavage with 0, 15 and 30 mg β-cyp/kg BW for 15 days. After 15-day treatments, the testes, epididymis and seminal vesicles were excised and weighed, respectively. One testis was used for testicular sperm head counts, and the other was for immunohistochemistry test to characterize the expression of androgen receptors (ARs). There were substantial decreases of both sperm head counts and daily sperm production after β-cyp exposure. The expression of AR decreased significantly in rats treated with 15 and 30 mg β-cyp/kg BW, and the gray scale pixel values in the three groups (0, 15 and 30 mg β-cyp/kg BW) were 113.79 ± 13.58, 96.09 ± 5.95 and 77.27 ± 5.44, respectively. These findings suggested β-cyp has significant adverse effects on the reproductive system. Reducing the expression of AR is a potential mechanism of decreased sperm production caused by β-cyp.

Pre-processing of inputs to a neural network model for better performance in traffic scene analysis

Artificial neural networks, which hold considerable potential for recognising and classifying spatial and temporal patterns, have been used as an efficient method for automatic traffic surveillance, which is an important research topic of intelligent transport systems. An important element in the performance of the neural networks is the composition of the input and output vectors, as well as the network architecture. However, there has been little research on the performance in relation to the attributes of the input and output vectors. In this research, various input vector properties were applied to the backpropagation model, which is the most popular neural network model, to see how the general performance would be affected by the different types of input vector. Experiments were performed with the inclusion of various grey levels, image sizes, edge detection images and combinations of edge and pixel grey information as the input vectors. The experimental results showed that the network performance, in terms of computing cost for training and prediction accuracy, was highly dependent on the characteristics of the input vectors. Two combined input vectors, the grey scale pixels and edge detection image, produced better prediction performance than either the grey values on the pixel or edges alone.

442 ULTRASONOGRAPHIC TESTICULAR ECHOTEXTURE IN NELORE BULLS

The objective of this research was to determine the minimum area representative of the testicular parenchyma echotexture in Nelore bulls, and to evaluate the presence of echotexture homogeneity between the right and left testicles and between different regions of testicle. Twenty-nine Nelore bulls raised under extensive management and free of reproductive disorders were used. The average body weight was 352.8 ± 51.0 kg and age ranged between 18 and 24 months. Echotexture was assessed using a portable ultrasonography device equipped with a 7.5-MHz linear transducer. All measurement was done by a single, experienced operator, and scanner settings that affect image attributes (i.e. proximal, distal, and total gains; focus area; brightness and contrast) were standardized to predetermined values. In the examinations, a layer of gel was applied to the transducer scanning area, which was positioned in the testicular longitudinal plane, proceeding with enough pressure to capture an image. The frozen images were obtained with minimal artifacts (refraction, dispersion, and attenuation of ultrasound waves) taking care to avoid the mediastinum testis and tunica albuginea, and recorded as .bmp files in a USB pen drive connected to the ultrasound device. Echotexture was defined in terms of mean pixel value quantified using values from 0 (black) to 255 (white) through the ImageJ 1.41 software. After the selection of a specific area of testicular parenchyma, the average tonality of the gray pixels in the selected region was calculated by the software and expressed in 256 gray-scales. Squares selections of 400 (20 × 20), 1600 (40 × 40), 3600 (60 × 60), and 6400 (80 × 80) pixels were assessed from images of the extremitas capitata, middle, and extremitas caudata regions of both testicles to determine the minimum sampling area of an image needed to represent the echotexture of testicular parenchyma. The normal distribution verification (Lilliefors test) of the variable mean pixel value was tested in each area, followed by variance analysis. The averages were compared through Tukey’s test with 5% significance. There was no significant difference between the different pixel areas assessed (P > 0.05), indicating that all were samples representative of testicular echotexture. Furthermore, the extremitas capitata, middle, and extremitas caudata regions showed no significant difference in echotexture (P > 0.05) regardless of the area analyzed, and there was no significant difference between the right and left testicles (P > 0.05) in any of the assessed areas. In conclusion, this research shows that testicular echotexture assessments can be made in Nelore bulls through selections of 400, 1600, 3600, or 6400 pixels, and that images can be captured from any region of any testicle. Fundect - Fundação deApoio ao Desenvolvimento do Ensino, CiÊncia e Tecnologia do Estado de Mato Grosso do Sul.

Carving surface modeling of images based on quadratic Bezier curved surface

Carving surface was directly modeled using the quadratic Bezier curve surface according to the grey or color pixels information of the image with clear texture and simple construction.This method segmented the image,analyzed and computed the pixel values and their position parameters for the sub-images,and used those values as feature parameters for constructing the surface patches of the model.The modeling was implemented by limited smooth connection of surface patches.The established surface model can describe the basic structure characteristics of the original objects in the image,and satisfy the requirements of digital carving processing.It has low complexity and strong practicability.

Changes in Relative Glucose Metabolic Rate Following Cortisol Administration in Aging Veterans with Posttraumatic Stress Disorder: An FDG-PET Neuroimaging Study

Changes in Relative Glucose Metabolic Rate Following Cortisol Administration in Aging Veterans with Posttraumatic Stress Disorder: An FDG-PET Neuroimaging Study

Implementation of automatic white-balance based on adaptive-luminance

A novel automatic white-balance algorithm based on adaptive-luminance is proposed in this paper. This algorithm redefines the gray pixels region, which can filter the gray pixels accurately. Furthermore, with the relations between gray pixels’ luminance with standard light source and their chroma Cb, Cr shifts with other color temperatures, the algorithm establishes the equations between the captured pixels and the original ones, which can estimate the gains of RGB channels exactly. To evaluate the proposed algorithm, the objective comparison method and the subjective observation method are both used, and the test results prove that the effects of image emendated by the proposed algorithm are excelled to that by traditional algorithms. Finally, the algorithm is implemented with VLSI design, and the result of synthesis proves that it can satisfy real-time application.

Multianalyte imaging in one-shot format sensors for natural waters

A one-shot multisensor based on ionophore–chromoionophore chemistry for optical monitoring of potassium, magnesium and hardness in water is presented. The analytical procedure uses a black and white non-cooled CCD camera for image acquisition of the one-shot multisensor after reaction, followed by data treatment for quantitation using the grey value pixel average from a defined region of interest from each sensing area to build the analytical parameter 1 − α. In optimised experimental conditions, the procedure shows a large linear range, up to 6 orders using the linearised model and good detection limits: 9.92 × 10 −5 mM, 1.86 × 10 −3 mM and 1.30 × 10 −2 mg L −1 of CaCO 3 for potassium, magnesium and hardness, respectively. This analysis system exhibits good precision in terms of relative standard deviation (RSD%) from 2.3 to 3.8 for potassium, from 5.0 to 6.8 for magnesium and from 5.4 to 5.9 for hardness. The trueness of this multisensor procedure was demonstrated comparing it with results obtained by a DAD spectrophotometer used as a reference. Finally, it was satisfactorily applied to the analysis of these analytes in miscellaneous samples, such as water and beverage samples from different origins, validating the results against atomic absorption spectrometry (AAS) as the reference procedure.

Statistical evaluation of methods for quantifying gene expression by autoradiography in histological sections.

BackgroundIn situ hybridisation (ISH) combined with autoradiography is a standard method of measuring the amount of gene expression in histological sections, but the methods used to quantify gene expression in the resulting digital images vary greatly between studies and can potentially give conflicting results.ResultsThe present study examines commonly used methods for analysing ISH images and demonstrates that these methods are not optimal. Image segmentation based on thresholding can be subject to floor-effects and lead to biased results. In addition, including the area of the structure or region of interest in the calculation of gene expression can lead to a large loss of precision and can also introduce bias. Finally, converting grey level pixel intensities to optical densities or units of radioactivity is unnecessary for most applications and can lead to data with poor statistical properties. A modification of an existing method for selecting the structure or region of interest is introduced which performs better than alternative methods in terms of bias and precision.ConclusionBased on these results, suggestions are made to reduce bias, increase precision, and ultimately provide more meaningful results of gene expression data.

Digital processing and evaluation of ultrasound images

With the help of workstations and PCs, on-site image processing has become possible. If the images are not available in digital form the video signal has to be A/D converted. In the case of colour images the colour channels R (red), G (green) and B (blue) have to be digitized separately. "Truecolour" imaging calls for an 8 bit resolution per channel, leading to 24 bits per pixel. Out of a pool of 2(24) possible values only the relevant 128 gray values and 64 shades of red and blue respectively needed for a colour-coded ultrasound image have to be isolated. Digital images can be changed and evaluated with the help of readily available image evaluation programmes. It is mandatory that during image manipulation the gray scale and colour pixels and LUTs (Look-Up-Table) must be worked on separately. Using relatively simple LUT manipulations astonishing image improvements are possible. Application of simple mathematical operations can lead to completely new clinical results. For example, by subtracting two consecutive colour flow images in time and special LUT operations, local acceleration of blood flow can be visualized (Colour Acceleration Imaging).

Black White Color and Gray Pixel Extraction Model

This is a design approach of software on image and pattern recognition, while eliminating the color and gray code of an image for comparison. This approach is quite effective for black and white and color images or scenes. Here we select particular part or parts of a given image and we compare with the contents of template-image (biometric) database. This approach will be the key idea for all the verifications and identification systems of Automated Biometric Analysis. Here the input is image (black and white or color) the output is a set of picture elements (pixels), we have various approaches they are (1) Minterm (minimized term) extraction for black and white image analysis and handling various gray levels through variables like A, B, C, D and the inverse (negative) image of the same with corresponding gray levels can also be maintained by their inverse like A', B',C',D'...respectively. (2) Maxterm (maximized term) the color images are generated by three primary colors (Red, Green, Blue) and this image can be recognized by both Minterm and Maxterm approaches and consider any one of the primary colors through Minterm approach and various gray levels of the primary color can be identified and analyzed by variables like A, B, C, D and the inverse (negative)image gray-levels can be performed by A',B',C',D',...respectively. Further the remaining two primary colors will be treated by the inverse of the earlier function of selected primary color (but not by the inverse variables) i.e., (A, B, C, D,) of primary color approach (maxterm approach).

Validation of a fully automated hippocampal segmentation method on patients with dementia.

We describe a fully automated method for hippocampal segmentation. The method uses SPM5 (http://www.fil.ion.ucl.ac.uk/spm/) software to segment the brain into grey/white matter, and spatially normalize the images to standard space. Grey matter pixels within a predefined hippocampal region in standard space are identified to segment the hippocampi. The method was validated on 36 subjects (9 each of Alzheimer's disease, dementia with Lewy bodies, vascular dementia, and healthy controls). The mean absolute difference in volume compared with manual segmentation was 11% (SD 9%). Linear regression between manual and automated volume gave V(auto) = V(manual) x 0.83 + 401 ml. The method provides an acceptable automated alternative to manual segmentation which may be of value in large studies.

PO polarography, contrast enhanced color duplex sonography (CDS), [18F] fluoromisonidazole and [18F] fluorodeoxyglucose positron emission tomography: validated methods for the evaluation of therapy-relevant tumor oxygenation or only bricks in the puzzle of tumor hypoxia?

BackgroundThe present study was conducted to analyze the value of ([18F] fluoromisonidazole (FMISO) and [18F]-2-fluoro-2'-deoxyglucose (FDG) PET as well as color pixel density (CPD) and tumor perfusion (TP) assessed by color duplex sonography (CDS) for determination of therapeutic relevant hypoxia. As a standard for measuring tissue oxygenation in human tumors, the invasive, computerized polarographic needle electrode system (pO2 histography) was used for comparing the different non invasive measurements.MethodsUntil now a total of 38 Patients with malignancies of the head and neck were examined. Tumor tissue pO2 was measured using a pO2-histograph. The needle electrode was placed CT-controlled in the tumor without general or local anesthesia. To assess the biological and clinical relevance of oxygenation measurement, the relative frequency of pO2 readings, with values ≤ 2.5, ≤ 5.0 and ≤ 10.0 mmHg, as well as mean and median pO2 were stated. FMISO PET consisted of one static scan of the relevant region, performed 120 min after intravenous administration. FMISO tumor to muscle ratios (FMISOT/M) and tumor to blood ratios (FMISOT/B) were calculated. FDG PET of the lymph node metastases was performed 71 ± 17 min after intravenous administration. To visualize as many vessels as possible by CDS, a contrast enhancer (Levovist®, Schering Corp., Germany) was administered. Color pixel density (CPD) was defined as the ratio of colored to grey pixels in a region of interest. From CDS signals two parameters were extracted: color hue – defining velocity (v) and color area – defining perfused area (A). Signal intensity as a measure of tissue perfusion (TP) was quantified as follows: TP = vmean × Amean.ResultsIn order to investigate the degree of linear association, we calculated the Pearson correlation coefficient. Slight (|r| > 0.4) to moderate (|r| > 0.6) correlation was found between the parameters of pO2 polarography (pO2 readings with values ≤ 2.5, ≤ 5.0 and ≤ 10.0 mmHg, as well as median pO2), CPD and FMISOT/M. Only a slight correlation between TP and the fraction of pO2 values ≤ 10.0 mmHg, median and mean pO2 could be detected. After exclusion of four outliers the absolute values of the Pearson correlation coefficients increased clearly. There was no relevant association between mean or maximum FDG uptake and the different polarographic- as well as the CDS parameters.ConclusionCDS and FMISO PET represent different approaches for estimation of therapy relevant tumor hypoxia. Each of these approaches is methodologically limited, making evaluation of clinical potential in prospective studies necessary.

Spatial-Temporal Current Source Correlations and Cortical Connectivity

The purpose of this study was to explore spatial-temporal correlations between 3-dimensional current density estimates using Low Resolution Electromagnetic Tomography (LORETA). The electroencephalogram (EEG) was recorded from 19 scalp locations from 97 subjects. LORETA current density was computed for 2,394 gray matter pixels. The gray matter pixels were grouped into 33 left hemisphere and 33 right hemisphere regions of interest (ROIs) based on groupings of Brodmann areas. The average source current density in a given region of interest (ROI) was computed for each 2 second epoch of EEG and then a Pearson product correlation coefficient was computed over the time series of successive 2 second epochs of current density between all pairwise combinations of ROIs during the resting eyes-closed EEG session. Rhythmic changes in source correlation as a function of distance were present in all regions of interest. Also, maximum correlations at certain frequencies were present independent of distance. The occipital regions exhibited the highest short distance correlations and the frontal regions exhibited the highest long distance correlations. In general, the right hemisphere exhibited higher intra-hemispheric source correlations than the left hemisphere especially in the temporal, parietal and occipital cortex. The strongest left vs. right hemisphere differences were in the alpha frequency band (8-12 Hz) and in the gamma frequency band (37-40 Hz). The pattern of spatial frequencies in different cortical lobules is consistent with differences in neural packing density and the operation of 'U' shaped fiber systems. The general conclusions were: 1--the higher the packing density then the greater the intra-cortical connection contribution to LORETA source correlations, 2--spatial frequencies are primarily due to intra-cortical 'U' shaped fiber connections and long distance fiber connections, 3--posterior and temporal cortical intra-hemispheric coupling is generally stronger in the right hemisphere than in the left hemisphere.

Contrast-Enhanced Color Duplex Sonography (CDS): an Alternative for the Evaluation of Therapy-Relevant Tumor Oxygenation?

To evaluate the predictive value of radiotherapeutically relevant tumor hypoxia by contrast-enhanced color duplex sonography (CDS). The objectification was based on pO2 histography. 25 patients with metastatic neck lymph node from a primary squamous carcinoma of the head and neck were examined. To visualize as many vessels as possible, a contrast enhancer (Levovist®, Schering Corp., Germany) was administered. Horizontal and longitudinal sonographic scans with a thickness of 5 mm were performed on the metastatic neck lymph node. Color pixel density (CPD) was defined as the ratio of colored to gray pixels in a region of interest. It represents the extent of vascularization in the investigated slice. To assess the biological and clinical relevance of oxygenation measurement, the relative frequency of pO2 readings ≤2.5, 5.0, and 10.0 mmHg, as well as mean and median pO2, were documented. In order to investigate the degree of linear association, the Pearson correlation coefficient was calculated. Moderate (|r| > 0.5) to high (|r| > 0.7) correlation was found between the CPD and the parameters of hypoxic fraction (pO2 readings with values ≤5.0 and 10.0 mmHg, as well as mean and median). There was only a slight correlation between CPD and the fraction of pO2 values ≤2.5 mmHg (r = −0.479). CPD represents the mean degree of vascularization. As a noninvasive measurement, this method seems feasible for evaluating the state of global oxygenation in superficial tumors. Nevertheless, this method is limited through its deficiency in describing the vascular heterogeneity of tumors.

Contrast-Enhanced Color Duplex Sonography (CDS): an Alternative for the Evaluation of Therapy-Relevant Tumor Oxygenation?

To evaluate the predictive value of radiotherapeutically relevant tumor hypoxia by contrast-enhanced color duplex sonography (CDS). The objectification was based on pO(2) histography. 25 patients with metastatic neck lymph node from a primary squamous carcinoma of the head and neck were examined. To visualize as many vessels as possible, a contrast enhancer (Levovist), Schering Corp., Germany) was administered. Horizontal and longitudinal sonographic scans with a thickness of 5 mm were performed on the metastatic neck lymph node. Color pixel density (CPD) was defined as the ratio of colored to gray pixels in a region of interest. It represents the extent of vascularization in the investigated slice. To assess the biological and clinical relevance of oxygenation measurement, the relative frequency of pO(2) readings < or = 2.5, 5.0, and 10.0 mmHg, as well as mean and median pO(2), were documented. In order to investigate the degree of linear association, the Pearson correlation coefficient was calculated. Moderate (/r/ > 0.5) to high (/r/ > 0.7) correlation was found between the CPD and the parameters of hypoxic fraction (pO(2) readings with values < or = 5.0 and 10.0 mmHg, as well as mean and median). There was only a slight correlation between CPD and the fraction of pO(2) values < or = 2.5 mmHg (r = -0.479). CPD represents the mean degree of vascularization. As a noninvasive measurement, this method seems feasible for evaluating the state of global oxygenation in superficial tumors. Nevertheless, this method is limited through its deficiency in describing the vascular heterogeneity of tumors.

Accurate atmospheric correction of ASTER thermal infrared imagery using the WVS method

The water vapor scaling (WVS) method involves an atmospheric correction algorithm for thermal infrared (TIR) multispectral data, designed mainly for the five TIR spectral bands of the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on the Terra satellite. First, this method is improved for better applicability to ASTER/TIR imagery. The major improvement is the determination of a water vapor scaling factor on a band-by-band basis, which can reduce most of the errors induced by various factors such as algorithm assumptions. Next, the WVS method is validated by assessing the surface temperature and emissivity retrieved for a global-based simulation model (416 448 conditions), 183 ASTER scenes selected globally, and ASTER scenes from two test sites, Hawaii Island and Tokyo Bay. In situ lake surface temperatures measured in 13 vicarious calibration experiments, Moderate Resolution Imaging Spectroradiometer sea surface temperature products, and a climatic lake temperature are also used in validation. All the results indicate that although the ASTER/TIR standard atmospheric correction algorithm performs less well in humid conditions, the WVS method will provide more accurate retrieval of surface temperature and emissivity in most conditions including notably humid conditions. The expected root mean square error is about 0.6 K in temperature. Since the WVS method will be degraded by errors in gray pixel selection and cloud detection, these processing steps should be applied accurately.

Image Reconstruction Using a Genetic Algorithm for Electrical Capacitance Tomography

Electrical capacitance tomography (ECT) has been used for more than a decade for imaging dielectric processes. However, because of its ill-posedness and non-linearity, ECT image reconstruction has always been a challenge. A new genetic algorithm (GA) developed for ECT image reconstruction uses initial results from a linear back-projection, which is widely used for ECT image reconstruction to optimize the threshold and the maximum and minimum gray values for the image. The procedure avoids optimizing the gray values pixel by pixel and significantly reduces the search space dimension. Both simulations and static experimental results show that the method is efficient and capable of reconstructing high quality images. Evaluation criteria show that the GA-based method has smaller image error and greater correlation coefficients. In addition, the GA-based method converges quickly with a small number of iterations.

Evaluation and Validity of a LORETA Normative EEG Database

To evaluate the reliability and validity of a Z-score normative EEG database for Low Resolution Electromagnetic Tomography (LORETA), EEG digital samples (2 second intervals sampled 128 Hz, 1 to 2 minutes eyes closed) were acquired from 106 normal subjects, and the cross-spectrum was computed and multiplied by the Key Institute's LORETA 2,394 gray matter pixel T Matrix. After a log10 transform or a Box-Cox transform the mean and standard deviation of the *.lor files were computed for each of the 2394 gray matter pixels, from 1 to 30 Hz, for each of the subjects. Tests of Gaussianity were computed in order to best approximate a normal distribution for each frequency and gray matter pixel. The relative sensitivity of a Z-score database was computed by measuring the approximation to a Gaussian distribution. The validity of the LORETA normative database was evaluated by the degree to which confirmed brain pathologies were localized using the LORETA normative database. Log10 and Box-Cox transforms approximated Gaussian distribution in the range of 95.64% to 99.75% accuracy. The percentage of normative Z-score values at 2 standard deviations ranged from 1.21% to 3.54%, and the percentage of Z-scores at 3 standard deviations ranged from 0% to 0.83%. Left temporal lobe epilepsy, right sensory motor hematoma and a right hemisphere stroke exhibited maximum Z-score deviations in the same locations as the pathologies. We conclude: (1) Adequate approximation to a Gaussian distribution can be achieved using LORETA by using a log10 transform or a Box-Cox transform and parametric statistics, (2) a Z-Score normative database is valid with adequate sensitivity when using LORETA, and (3) the Z-score LORETA normative database also consistently localized known pathologies to the expected Brodmann areas as an hypothesis test based on the surface EEG before computing LORETA.

Automatic normalization of satellite images using unchanged pixels within urban areas

Radiometric normalization is often required in remote sensing image analysis particularly in land change analysis. The normalization minimizes different imaging condition effects in analysis and rectifies radiometry of images in such a way as if they have been acquired at the same imaging conditions. Relative radiometric normalization which is normally applied in image preprocessing stage does not remove all unwanted effects. In this paper, an automatic normalization method has been developed based on regression applied on unchanged pixels within urban areas. The proposed method is based on efficient selection of unchanged pixels through image difference histogram modeling using available spectral bands and calculation of relevant coefficients for dark, gray and bright pixels in each band. The coefficients are applied to produce the normalized image. The idea has been implemented on two TM image datasets. The capability of the approach in taking into account the imaging condition differences and effectively excluding real land change pixels from the normalization process has shown better performance in the evaluation stage.

Parametric vs. Non-Parametric Statistics of Low Resolution Electromagnetic Tomography (LORETA)

This study compared the relative statistical sensitivity of non-parametric and parametric statistics of 3-dimensional current sources as estimated by the EEG inverse solution Low Resolution Electromagnetic Tomography (LORETA). One would expect approximately 5% false positives (classification of a normal as abnormal) at the P < .025 level of probability (two tailed test) and approximately 1% false positives at the P < .005 level. EEG digital samples (2 second intervals sampled 128 Hz, 1 to 2 minutes eyes closed) from 43 normal adult subjects were imported into the Key Institute's LORETA program. We then used the Key Institute's cross-spectrum and the Key Institute's LORETA output files (*.lor) as the 2,394 gray matter pixel representation of 3-dimensional currents at different frequencies. The mean and standard deviation *.lor files were computed for each of the 2,394 gray matter pixels for each of the 43 subjects. Tests of Gaussianity and different transforms were computed in order to best approximate a normal distribution for each frequency and gray matter pixel. The relative sensitivity of parametric vs. non-parametric statistics were compared using a "leave-one-out" cross validation method in which individual normal subjects were withdrawn and then statistically classified as being either normal or abnormal based on the remaining subjects. Log10 transforms approximated Gaussian distribution in the range of 95% to 99% accuracy. Parametric Z score tests at P < .05 cross-validation demonstrated an average misclassification rate of approximately 4.25%, and range over the 2,394 gray matter pixels was 27.66% to 0.11%. At P < .01 parametric Z score cross-validation false positives were 0.26% and ranged from 6.65% to 0% false positives. The non-parametric Key Institute's t-max statistic at P < .05 had an average misclassification error rate of 7.64% and ranged from 43.37% to 0.04% false positives. The nonparametric t-max at P < .01 had an average misclassification rate of 6.67% and ranged from 41.34% to 0% false positives of the 2,394 gray matter pixels for any cross-validated normal subject. In conclusion, adequate approximation to Gaussian distribution and high cross-validation can be achieved by the Key Institute's LORETA programs by using a log10 transform and parametric statistics, and parametric normative comparisons had lower false positive rates than the non-parametric tests.