Schizophrenia has been associated with aberrant intrinsic functional organization of the brain but the relationship of such deficits to psychopathology is unclear. In this study, we investigated associations between resting-state networks and individual psychopathology in sixteen patients with paranoid schizophrenia and sixteen matched healthy control ...

... Right: Ratio of the RMS wavefront aberration to the original comatic RMS wavefront aberration as a function of the decenter E (full line), and the ...

Functional neuroimaging studies on cognitive dysfunction in schizophrenia have suggested regional brain activation changes in the dorsolateral prefrontal cortex and the medial temporal lobe. However, less is known about the functional coupling of these areas during cognitive performance. In this study, we used functional magnetic ...

We present the case of an 80-year-old female with acute right fronto-parietal stroke and an interesting neurological sign on clinical examination; the arm levitation sign. We discuss the imaging correlates of this sign and hypothesize on the possible functional etiology of the sign. We also discuss in brief, the possibility of neuronal misconnections ...

Adolescent offspring of schizophrenia patients (HR-S) are an important group in whom to study impaired brain function and structure, particularly of the frontal cortices. Studies of working memory have suggested behavioral deficits and fMRI-measured hypoactivity in fronto-parietal regions in these subjects. Independent structural MRI (sMRI) studies have ...

Several functional MRI (fMRI) activation studies have highlighted specific differences in brain response in social anxiety disorder (SAD) patients. Little is known, so far, about the changes in the functional architecture of resting state networks (RSNs) in SAD during resting state. We investigated statistical differences in RSNs on 20 SAD and 20 controls ...

... up lo several times the Airy disk (for ... of moments of the apodizing function and resulting ... linear equations of aberration functions which minimize the ...

A definition of a wave aberration as a phase shift upon composition of light waves in the image of a point is given using the concept of point eikonal. An expression that determines the total differential of a wave aberration function is obtained and the condition of its integrability is determined. The sequence of the wave ...

While schizophrenia is frequently characterized as a disorder of disturbed functional connectivity, the causes and pathophysiological origins of such disturbances remain unclear. The aim of this study was to better elucidate the mechanistic causes of abnormal functional connectivity in schizophrenia, measured as the extent of temporal correlation between ...

Page 1. AD Award Number: W81XWH-04-1-0049 TITLE: Aberrant AR Signaling as a Function of Declining Androgen PRINCIPAL ...

This event-related functional magnetic resonance imaging (fMRI) study was designed in such a manner so as to contribute to the present debate on behavioural and functional transfer effects associated with intensive language training. To address this novel issue, we measured professional simultaneous interpreters and control subjects while they performed a ...

Prefrontal-parietal networks are essential to many cognitive processes, including the ability to differentiate new from previously presented items. As patients with schizophrenia exhibit structural abnormalities in these areas along with well-documented decrements in recognition memory, we hypothesized that these patients would demonstrate memory-related abnormalities in prefrontal and parietal ...

The neural mechanism by which patients spontaneously recover cognitive function after brain injury is not understood. Here we demonstrate for the first time that aphasic patients, who have largely recovered language function, show increased frontoparietal integration. A similar change in functional connectivity is ...

... for various diffraction functions for optimum balanced third-order spherical aberration. ... from the design data for rotationally symmetric aberrations. ...

During childhood and adolescence, ongoing white matter maturation in the fronto-parietal cortices and connecting fiber tracts is measurable with diffusion-weighted imaging. Important questions remain, however, about the links between these changes and developing cognitive functions. Spatial working memory (SWM) performance improves significantly throughout ...

Developmental neuropsychology and functional neuroimaging evidence indicates that simple and complex mental calculation is subserved by a fronto-parietal network. However, the effective connectivity (connection direction and strength) among regions within the fronto-parietal network is still unexplored. Combining event-related fMRI and ...

The induction of chromosomal aberrations by radiation is an old and new problem in radiation biology. The studies on radiation-induced chromosomal aberrations have contributed to understanding the structure and function of chromosomes which are endowed wi...

A simple exact method is presented for evaluating the circularly symmetric Fresnel-Kirchhoff diffraction integral in the presence of Seidel aberrations, all orders of spherical aberration, and all orders of linear coma. The resultant formulas involve a simple quadrature over a single special function of mathematics.

The mitogen-activated protein kinases extracellular signal-regulated kinase (ERK)1 and 2 are essential intracellular mediators of numerous transmembrane signals. To investigate neural-specific functions of ERK2 in the brain, we used a Cre/lox strategy using Nestin:Cre to drive recombination in neural precursor cells. Nestin:Cre;ERK2^fl/fl conditional ...

Recent studies have reported that cognitive inflexibility associated with impairments in a frontal-striatal circuit and parietal region is a core cognitive deficit of obsessive-compulsive disorder (OCD). However, few studies have examined progressive changes in these regions following clinical improvement in obsessive-compulsive symptoms. To determine if treatment changes the ...

Asymptotic expressions are derived for the two-dimensional incoherent optical transfer function (OTF) of an optical system with defocus and spherical aberration. The two-dimensional stationary phase method is used to evaluate the aberrated OTF at large and moderately large defocus and spherical aberration. For ...

The quantitative analysis of the effect of aberrations in human eye on vision has important clinical value in the correction of aberrations. The wave-front aberrations of human eyes were measured with the Hartmann-Shack wave-front sensor and modulation transfer function (MTF) was computed from the wave-front ...

Spatial selective attention is widely considered to be right hemisphere dominant. Previous functional magnetic resonance imaging studies, however, have reported bilateral blood-oxygenation-level-dependent responses in dorsal frontoparietal regions during anticipatory shifts of attention to a location (Kastner et al., 1999; Corbetta et al., 2000; Hopfinger ...

Spatial selective attention is widely considered to be right hemisphere dominant. Previous functional magnetic resonance imaging (fMRI) studies, however, have reported bilateral blood-oxygenation-level-dependent (BOLD) responses in dorsal fronto-parietal regions during anticipatory shifts of attention to a location (Kastner et al., 1999; Corbetta et al., ...

A method to measure wave aberrations in the isolated crystalline lens is demonstrated. The method employs a laser scanning technique in which the trajectories of narrow refracted laser beams are measured for an array of sample positions incident on the lens. The local slope of the emerging wavefront is calculated for each sample position, and a least squares procedure is used ...

Visual working memory (VWM) is used to maintain sensory information for cognitive operations, and its deficits are associated with several neuropsychological disorders. VWM is based on sustained neuronal activity in a complex cortical network of frontal, parietal, occipital, and temporal areas. The neuronal mechanisms that coordinate this distributed processing to sustain coherent mental images ...

Short-term memory (STM), or the ability to hold verbal information in mind for a few seconds, is known to rely on the integrity of a frontoparietal network of areas. Here, we used functional magnetic resonance imaging to ask whether a similar network is engaged when verbal information is conveyed through a visuospatial language, American Sign Language, ...

Survival can depend on the ability to change a current course of action to respond to potentially advantageous or threatening stimuli. This �reorienting� response involves the coordinated action of a right hemisphere dominant ventral frontoparietal network that interrupts and resets ongoing activity and a dorsal frontoparietal network specialized for ...

Many researchers have noted that the functional architecture of the human brain is relatively invariant during task performance and the resting state. Indeed, intrinsic connectivity networks (ICNs) revealed by resting-state functional connectivity analyses are spatially similar to regions activated during cognitive tasks. This suggests that patterns of ...

Mankind is unique in her ability for observational learning, i.e. the transmission of acquired knowledge and behavioral repertoire through observation of others' actions. In the present study we used electrophysiological measures to investigate brain mechanisms of observational learning. Analysis investigated the possible functional coupling between occipital (alpha) and motor ...

Recent studies in patients with disorders of consciousness (DOC) tend to support the view that awareness is not related to activity in a single brain region but to thalamo-cortical connectivity in the frontoparietal network. Functional neuroimaging studies have shown preserved albeit disconnected low-level cortical activation in response to external ...

The hypothesis that overdispersion of the chromosome aberration number per cell results from multiple aberrations per particle traversal is investigated in mathematical terms. At a given absorbed dose, Poisson distributions are assumed both for the number of ionizing particles traversing a cell nucleus and for the number of aberrations ...

The classical aberrations of an anamorphic optical imaging system, representing the terms of a power-series expansion of its aberration function, are separable in the Cartesian coordinates of a point on its pupil. We discuss the balancing of a classical aberration of a certain order with one or more such ...

synmclric Gaussian-!ikc function. By the tirnc you add aberrations and scanner ... smear is a Gaussian function with a I:WIIM of 1.313 spatial samples and a ...

Dysregulation in cognitive control networks may mediate core characteristics of drug addiction. Cocaine dependence has been particularly associated with low activation in the frontoparietal regions during conditions requiring decision making and cognitive control. This functional magnetic resonance imaging (fMRI) study aimed to examine differential ...

The transfer function of a grating interferometer with aberrated gratings is discussed. A geometrical configuration is developed that minimizes the aberrations of the output fringes in the interferometer, which is constructed with three hyperbolic gratings. Theoretical and experimental investigations show that it is possible to ...

aberration functions. For spherical aberration, this calculation was first done by Black and Linfoot.'9 Using-aperture sys- tems. Black and Linfoot and the present authors do not think so,but, as stated in Section 1,it. Linfoot, "Spherical aberration and the in- formation content of optical images," Proc. R. Soc. ...

... Abstract : Our group previously showed that FOXO proteins are aberrantly localized to the cytoplasm in cells that have sustained loss of functional ...

This is a very weak function of mask efficiency; the integration time favors masks that reduce sensitivity to aberrations at the expense of throughput. ...

... We have linked the work of cancer geneticists with cell biologists to begin to understand the functional role that some of the consistently aberrantly ...

... on diverse posttranslational modifications of amino termini (36, 47) and the more recently implicated globular domains of histones (6). These ...

... We explored the possibility that different testosterone levels may influence prostate tumor growth. We have completed the ...

In this article, we have reviewed recent findings from our laboratory, originally presented in Hugdahl et al. (2008). These findings reveal that auditory hallucinations in schizophrenia should best be conceptualized as internally generated speech mis-representations lateralized to the left superior temporal gyrus and sulcus, not cognitively suppressed due to enhanced attention to the �voices� ...

Although the retinal image is typically polychromatic, few studies have examined polychromatic image quality in the human eye. We begin with a conceptual framework including the formulation of a psychophysical linking hypothesis that underlies the utility of image quality metrics based on the polychromatic point-spread function. We then outline strategies for computing ...

The analysis models of Zernike aberrations of precision conformal aspheric optical windows are built, and the influences on Zernike aberrations of different aspheric optical window shapes and the variation laws of Zernike aberrations of precision conformal optical windows at different gimbal angles are analyzed using the ...

BackgroundThe default network is a set of brain regions that exhibit a reduction in BOLD response during attention-demanding cognitive tasks, and distinctive patterns of functional connectivity that typically include anti-correlations with a fronto-parietal network involved in attention, working memory, and executive control. The ...

This study investigates whether the monitoring role that has been ascribed to the right lateral prefrontal cortex in various cognitive domains also applies to the spatial domain. Specific questions of the study were (i) what kind of spatial contingencies trigger the putative monitoring function of right lateral prefrontal cortex and (ii) which other brain regions are ...

Dynamic changes in brain structure, activation, and cognitive abilities co-occur during development, but little is known about how changes in brain structure relate to changes in cognitive function or brain activity. By using cortical pattern matching techniques to correlate cortical gray matter thickness and functional brain activity over the entire brain ...

We present an experiment, well adapted for students of introductory optics courses, for the visualization of the impact of spherical aberration in the point spread function of imaging systems. The demonstrations are based on the analogy between the point-spread function of spherically aberrated systems, and the ...

Sensitivity theory divides the causes of challenging behavior into three categories, aberrant contingencies, aberrant environments, and aberrant motivation. This paper replies to criticism that sensitivity theory is circular and unsupported by empirical evidence by reporting on studies that support the theory and rejecting the idea ...

A method for classifying a patient's eye includes the steps of: obtaining normal and abnormal wavefront aberration data from normal and abnormal eyes; fitting the normal and abnormal eye wavefront aberration data with a basis function to decompose the nor...

Modulation transfer function of the dioptrics of the human eye for white light were calculated for different pupil sizes from experimental data on the aberrations. The largest aberration is the chromatic difference of focus. Since this is well known quant...

BackgroundThe psychotomimetics ketamine and MK-801, non-competitive NMDA receptor (NMDAr) antagonists, induce cognitive impairment and aggravate schizophrenia symptoms. In conscious rats, they produce an abnormal behavior associated with a peculiar brain state characterized by increased synchronization in ongoing ? (30�80 Hz) oscillations in the frontoparietal (sensorimotor) ...

The advantages and disadvantages of single and double mirror systems are considered. Geometrical image aberrations of spherical and paraboloidal single mirrors are given as functions of the focal number and angle of field, and geometrical image aberrations of paraboloidal-hyperboloidal double mirror systems are given as ...

The definition of the generalized optical path function for a grating or mirror with a single plane of symmetry is reviewed. The generalized optical path function is then expanded in a series of wavefront aberration terms using only a few lines of code in the Mathematica{trademark} scientific programming environment. The use of the ...

This paper is an attempt to provide new insight into the behavior of near-field scalar diffraction phenomena by showing that the Rayleigh-Sommerfeld diffraction integral is equivalent to the Fourier transform integral of a generalized pupil function which includes a term that represents phase errors in the aperture. This term can be interpreted as describing a conventional ...

Visual line bisection is a reliable and valid laterality task that is typically used with patients with acquired brain damage to assess right hemisphere functioning. Neurologically normal individuals tend to bisect lines to the left of the objective midline whereas those with right parietal damage bisect lines to the right. In this study children with ADHD were matched with ...

Global workspace (GW) theory emerged from the cognitive architecture tradition in cognitive science. Newell and co-workers were the first to show the utility of a GW or "blackboard" architecture in a distributed set of knowledge sources, which could cooperatively solve problems that no single constituent could solve alone. The empirical connection with conscious cognition was made by Baars (1988, ...

We combined measures from event-related functional magnetic resonance imaging (fMRI), diffusion tensor imaging (DTI), and cognitive performance (visual search response time) to test the hypotheses that differences between younger and older adults in top-down (goal-directed) attention would be related to cortical activation, and that white matter integrity as measured by DTI ...

Vegetative and minimally conscious states diagnosis remained a major clinical challenge. New paradigms such as measurement of the global cerebral metabolism, the structural and functional integrity of fronto-parietal network, or the spontaneous activity in resting state have been shown to be helpful to disentangle vegetative from minimally conscious ...

BackgroundMost prior studies on selective attention in the setting of total sleep deprivation (SD) have focused on behavior or activation within fronto-parietal cognitive control areas. Here, we evaluated the effects of SD on the top-down biasing of activation of ventral visual cortex and on functional connectivity between cognitive control and other brain ...

Previous studies show that (1) two members of fos family transcription factors, c-Fos and FosB, are induced in frontal brain regions by methamphetamine; (2) null mutation of c-Fos exacerbates methamphetamine-induced neurotoxicity; and (3) null mutation of FosB enhances behavioral responses to cocaine. Here we sought a role of FosB in responses to methamphetamine by studying FosB null mutant (-/-) ...

Previous studies show that (1) two members of fos family transcription factors, c-Fos and FosB, are induced in frontal brain regions by methamphetamine; (2) null mutation of c-Fos exacerbates methamphetamine-induced neurotoxicity; and (3) null mutation of FosB enhances behavioral responses to cocaine. Here we sought a role of FosB in responses to methamphetamine by studying FosB null mutant (?/?) ...

Wave aberrations degrade the optical quality of the eye relative to the diffraction limit, but there are situations in which having slightly aberrated optics can provide some relative visual benefits. This fact led us to consider whether interactions among aberrations in the eye's wavefront produce an advantage for image quality ...

The development of technology to measure and correct the eye's higher-order aberrations, i.e., those beyond defocus and astigmatism, raises the issue of how much visual benefit can be obtained by providing such correction. We demonstrate improvements in contrast sensitivity and visual acuity in white light and in monochromatic light when adaptive optics corrects the eye's ...

A sixth-order theory of wave aberrations for axially symmetric systems is developed. Specific formulas for the sixth-order extrinsic and intrinsic wave aberration coefficients are given, as well as relations between pupil and image aberrations. Equations are developed for the wavefront propagation to the sixth order of approximation. ...

Two different methods have been derived and implemented for simulation of multipole imaging systems and aberration correctors. The first method uses an aberration theory for combinations of multipole lenses and deflectors, including primary and secondary aberrations up to the fifth order. A damped least-squares algorithm is used to ...

We derive the bit error rate (BER) of inter-satellite laser communication (lasercom) links with on�off-keying systems in the presence of both wave-front aberrations and pointing error, but without considering the noise of the detector. Wave-front aberrations induced by receiver terminal have no influence on the BER, while wave-front ...

This paper is focus on analyzing the telescopes used in atmosphere, which studies the effect of optical aberration of telescopes to the laser radar. The method of numerical simulation is used to calculate and analyze the characters of backward wave when laser beam propagates through atmosphere and reflects back. Then make use of optical transfer function ...

Even the best optical microscopes available on the market exhibit chromatic aberrations to some extent. In some types of study, chromatic aberrations of current optics cannot be neglected and a software correction is highly desirable. This paper describes a novel method of chromatic aberration measurement and software correction using ...

Volumetric memories based on the extension of conventional approaches by using the third dimension for multiple layers may offer dramatic increases in storage capacity. For such thick- media multilayer systems, the design of the optical head includes challenges in the control and tolerancing of aberration accumulation throughout the focal depth. In this paper we review the ...

We examine the effects of aberrations induced by a refractive index mismatch on the signal level and resolution of single-photon (1-p) and two-photon (2-p), conventional and confocal scanning microscopes. In particular, we consider the aberrations introduced by an interface between oil/glass and water. Resolution is defined in terms of enclosed ...

We examine the effects of aberrations induced by a refractive index mismatch on the signal level and resolution of single-photon (1-p) and two-photon (2-p), conventional and confocal scanning microscopes. In particular, we consider the aberrations introduced by an interface between oil/glass and water. Resolution is defined in terms of enclosed ...

The ability to actively locate potential threats in our environment is highly adaptive. To investigate mediating neural mechanisms, we designed a visual search task in which central cues signaled future location and emotional expression (angry or neutral) of a target face. Cues predicting angry targets accelerated subsequent attention shifts, indicating that endogenous signals predicting ...

The coupling process between observed and performed actions is thought to be performed by a fronto-parietal perception-action system including regions of the inferior frontal gyrus and the inferior parietal lobule. When investigating the influence of the movements' characteristics on this process, most research on action observation has focused on only one particular variable ...

The coupling process between observed and performed actions is thought to be performed by a fronto-parietal perception-action system including regions of the inferior frontal gyrus and the inferior parietal lobule. When investigating the influence of the movements' characteristics on this process, most research on action observation has focused on only one particular variable ...

Reaching and grasping in primates depend on the coordination of neural activity in large frontoparietal ensembles. Here we demonstrate that primates can learn to reach and grasp virtual objects by controlling a robot arm through a closed-loop brain�machine interface (BMIc) that uses multiple mathematical models to extract several motor parameters (i.e., hand position, ...

Organisms operate within both a perceptual domain of objects and events, and a mnemonic domain of past experiences and future goals. Each domain requires a deliberate selection of task-relevant information, through deployments of external (perceptual) and internal (mnemonic) attention, respectively. Little is known about the control of attention shifts in working memory, or whether voluntary ...

Dexterous manipulation requires both strength, the ability to produce fingertip forces of a specific magnitude, and dexterity, the ability to dynamically regulate the magnitude and direction of fingertip force vectors and finger motions. Although cortical activity in fronto-parietal networks has been established for stable grip and pinch forces, the cortical regulation in the ...

According to the Baddeley-Hitch model, phonological and visuospatial representations are separable components of working memory (WM) linked by a central executive. The traditional view that the separation reflects the relative contribution of the 2 hemispheres (verbal WM--left; spatial WM--right) has been challenged by the position that a common bilateral frontoparietal ...

For a diverging electron beam with parabolic space-charge density distribution, first-order perturbation theory is used to derive an analytic expression, yielding the aberrations as a function of the covered distance. Application of the derived expression shows that the performance of electrostatic projection TV guns may be severely degraded by the ...

Presented here is a characterization of aberration in medical ultrasound imaging. The characterization is optimal in the sense of maximizing the expected energy in a modified beamformer output of the received acoustic backscatter. Aberration correction based on this characterization takes the form of an aberration correction filter. ...

Impaired consciousness requires altered cortical function. This can occur either directly from disorders that impair widespread bilateral regions of the cortex or indirectly through effects on subcortical arousal systems. It has therefore long been puzzling why focal temporal lobe seizures so often impair consciousness. Early work suggested that altered consciousness may occur ...

and the associated PSFs for one of the sub- jects. The desired aberrations were kept stable by the AO system working aberrations(a) 0 45 90 135 180 225 270 315 40arcmin rotated PSFs(b) Figure 2. Example of the wavefront aberration (a) and the asso- ciated point-spread functions (PSFs) (b) for the normal (0) and the ...

A matrix method to do nonlinear calculations is described. This is possible only under the special condition when a transformation maps a zero vector onto a zero vector. Geometrical optics conform to this condition and hence matrix methods can be applied to calculate aberrations. Methods to reduce computational complexities using symmetry arguments are provided. The formalism ...

Evidence suggests that the right inferior frontal cortex (IFC) plays a specialized role in response inhibition. However, more recent findings indicate a broader role for this region in attentional control. Here, we used functional magnetic resonance imaging to examine the functional role of the right IFC in attention, inhibition, and response control in 2 ...

Turner syndrome is associated with spatial and numerical cognitive impairments. We hypothesized that these nonverbal cognitive impairments result from limits in spatial and temporal processing, particularly as it affects attention. To examine spatiotemporal attention in girls with Turner syndrome versus typically developing controls, we used a multiple object tracking task during ...

Turner syndrome is associated with spatial and numerical cognitive impairments. We hypothesized that these nonverbal cognitive impairments result from limits in spatial and temporal processing, particularly as it affects attention. To examine spatiotemporal attention in girls with Turner syndrome versus typically developing controls, we used a multiple object tracking task during ...

Mar 1, 2011 ... IPO is so named because it computes wave-front aberrations of the telescope from digitized pointspread functions (PSFs) measured in infocus ...

Apr 21, 2011 ... Because induction of chromosome aberrations is a non-linear function of radiation dose, a graded series of four different radiation ...

systems which have no chromatic aberrations and whose transmission losses are a function of the spectral reflectivity of the mirror coatings. ...

and limphocytes, RMC, HCT116, 80S4 Tumor induction and Tamoxifen protective effects and chromosomal aberrations B

... Abstract : Our hypothesis that the human PPC-1 prostate tumor cell lines with experimentally altered Ets transcription factor function, which show a ...

... Abstract : Our hypothesis that the human PPC-1 prostate tumor cell lines with experimentally altered Ets transcription factor function, which show a ...

... to demonstrate that BCSG1 expression in breast cancer cells directly inhibits the mitotic checkpoint function and induces aneuploidy in a BubRI ...

... to demonstrate that BCSG1 expression in breast cancer cells directly inhibits the mitotic checkpoint function and induces aneuploidy in a BubR1 ...

... volume of a 2.54 cm focal length aberration ... function which, in turn, is caused by free ... as the multiphoton-polaron absorption mechanisms of laser ...

incidence angle on the array. The average over all incidence angles is also ... as a function of velocity aberration and incidence angle are also listed for ...

... We reasoned that aberrant 4.1 expression could engender defects in functions of centrosomes, mitotic spindles and in cytokinesis. ...

... Jour. Motion Picture and Television Engineers, Vol.69, ... 6 2, 1956 5 HH Hopkins Wave Theory of Aberrations, 0.UP, 1950 ...

... sites identified as related to S ... Defense (DoD) Issuances (current and cancelled ... PILOT STUDIES, MICE, SENSE ORGANS, ANATOMICAL MODELS. ...

Mar 1, 2011 ... IPO is so named because it computes wave-front aberrations of the telescope from digitized pointspread functions (PSFs) measured in infocus ...

During sustained periods of a taxing cognitive workload, humans typically display time-on-task (TOT) effects, in which performance gets steadily worse over the period of task engagement. Arterial spin labeling (ASL) perfusion functional magnetic resonance imaging (fMRI) was used in this study to investigate the neural correlates of TOT effects in a group of 15 subjects as they ...

During sustained periods of a taxing cognitive workload, humans typically display time-on-task (TOT) effects, in which performance gets steadily worse over the period of task engagement. Arterial spin labeling (ASL) perfusion functional magnetic resonance imaging (fMRI) was used in this study to investigate the neural correlates of TOT effects in a group of 15 subjects as they ...

Several current models hold that frontoparietal areas exert cognitive control by biasing task-relevant processing in other brain areas. Previous event-related functional magnetic resonance imaging (fMRI) studies have compared prosaccades and antisaccades, which require subjects to look toward or away from a flashed peripheral stimulus, respectively. These ...

A network of brain regions including the ventral premotor cortex (vPMc) and the posterior parietal cortex (PPc) is consistently recruited during processing of multisensory stimuli within peripersonal space (PPS). However, to date, information on the causal role of these fronto-parietal areas in multisensory PPS representation is lacking. Using low-frequency repetitive TMS ...

Behavioral studies indicate that subjects are able to divide attention between multiple streams of information at different locations. However, it is still unclear to what extent the observed costs reflect processes specifically associated with spatial attention, versus more general interference due the concurrent monitoring of multiple streams of stimuli. Here we used a factorial design to ...

by multiplying the pupil function by a calculated aberration function. PSFs calculated from such a modified pupil function closely match the corresponding measured PSFs collected under the aberrated imaging conditions. When used for image deconvolution of simulated objects, these ...

Functional analysis results for multiple topographies of aberrant behavior were graphed in an aggregate fashion and then separately for 48 clients. The results indicated that multiple topographies of behavior may be maintained by different contingencies. These results indicate that graphing functional analysis data in an aggregate ...

Previous reports suggest that the internal organization of semantic memory is in terms of different "types of knowledge," including "sensory" (information about perceptual features), "action" (motor-based knowledge of object utilization), and "functional" (abstract properties, as function and context of use). Consistent with this view, a specific loss of ...

Behavioral and functional neuroimaging studies indicate deficits in verbal working memory (WM) and frontoparietal dysfunction in individuals with dyslexia. Additionally, structural brain abnormalities in dyslexics suggest a dysconnectivity of brain regions associated with phonological processing. However, little is known about the ...

Behavioral and functional neuroimaging studies indicate deficits in verbal working memory (WM) and frontoparietal dysfunction in individuals with dyslexia. Additionally, structural brain abnormalities in dyslexics suggest a dysconnectivity of brain regions associated with phonological processing. However, little is known about the ...

When using a laser guide star (LGS) adaptive optics (AO) system, quasi-static aberrations are observed between the measured wavefronts from the LGS wavefront sensor (WFS) and the natural guide star (NGS) WFS. These LGS aberrations, which can be as much as 1200 nm RMS on the Keck II LGS AO system, arise due to the finite height and structure of the sodium ...

The analysis and measurement of the wavefront aberration function are very important tools that allow us to evaluate the performance of any specified optical system. This technology has been adopted in visual optics for the analysis of optical aberrations in the human eye, before and after being subjected to laser refractive surgery. ...

BackgroundPrimary leptomeningeal astrocytomas are rare intracranial tumors. These tumors are believed to originate from cellular nests which migrate by means of aberration, ultimately settling in the leptomeningeal structure. They may occur in both solitary and diffuse forms. The literature reports only fifteen cases of solitary primary intracranial leptomeningeal ...

Adhesion-GPCRs provide essential cell-cell and cell-matrix interactions in development, and have been implicated in inherited human diseases like Usher Syndrome and bilateral frontoparietal polymicrogyria. They are the second largest subfamily of seven-transmembrane spanning proteins in vertebrates, but the function of most of these receptors is still not ...

Event knowledge is organized on the basis of goals that enable the selection of specific event sequences to organize everyday life activities. Although the medial prefrontal cortex represents event knowledge, little is known about its role in mediating event knowledge complexity. We used functional MRI to investigate the patterns of brain activation while healthy volunteers ...

Adhesion-GPCRs provide essential cell-cell and cell-matrix interactions in development, and have been implicated in inherited human diseases like Usher Syndrome and bilateral frontoparietal polymicrogyria. They are the second largest subfamily of seven-transmembrane spanning proteins in vertebrates, but the function of most of these receptors is still not ...

AbstractObjectiveThis article reviews the available scientific literature concerning the neurobiological substrates of Tourette's disorder (TD).MethodsThe electronic databases of PubMed, ScienceDirect, and PsycINFO were searched for relevant studies using relevant search terms.ResultsNeuropathological as well as structural and functional neuroimaging studies of TD implicate ...

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an inherited neurologic disorder with macrocephaly before the age of one and slowly progressive deterioration of motor functions. Magnetic resonance imaging shows diffusely abnormal and swollen white matter of the cerebral hemispheres and the presence of subcortical cysts in the anterior-temporal region and ...

In an object-centered representation, the position of the subparts of an object are encoded with respect to a set of axes and an origin centered on the object. Several physiological and neuropsychological results support the existence of such representations in humans and monkeys. An explicit representation would involve neurons with invariant response properties in object-centered coordinates. We ...

An expression has been deduced theoretically from a schematic-eye model, for the transverse or lateral chromatic aberration (TCA) after refractive surgery. The aim was to investigate analytically how chromatic aberration varies after the emmetropization process. These changes in the TCA have been characterized from changes in corneal asphericity. The ...

The mechanism of coating induced polarization state variation is analysed by the Jones matrix. Pauli spin matrices are used to establish the relationship between coating induced polarization state variation and polarization aberrations. To reduce coating induced polarization aberrations, we propose that ? = 0 and Ts = Tp at arbitrary incident angle should ...

Polychromatic defocus could affect the optimal residual spherical aberration that could yield the best image quality for patients with intraocular lenses (IOLs). Modulation transfer functions (MTFs) were generated using a model that included polychromatic defocus. The maximum MTF volume occurred at + 0.05 ?m of overall ocular spherical ...

Adaptive optics systems typically include an optical relay that simultaneously images the science field to be corrected and also a set of pupil planes conjugate to the deformable mirror of the system. Often, in the optical spaces where DM's are placed, the pupils are aberrated, leading to a displacement and/or distortion of the pupil that varies according to field ...

Tourette syndrome (TS) is a developmental disorder characterized by unwanted, repetitive behaviours that manifest as stereotyped movements and vocalizations called �tics�. Operating under the hypothesis that the brain's control systems may be impaired in TS, we measured resting-state functional connectivity MRI (rs-fcMRI) between 39 previously defined putative control ...

Tourette syndrome (TS) is a developmental disorder characterized by unwanted, repetitive behaviours that manifest as stereotyped movements and vocalizations called "tics". Operating under the hypothesis that the brain's control systems may be impaired in TS, we measured resting-state functional connectivity MRI (rs-fcMRI) between 39 previously defined putative control regions ...

Task switching requires executive control processes that undergo age-related decline. Previous neuroimaging studies have identified age-related differences in brain activation associated with global switching effects (dual-task blocks vs. single-task blocks), but age-related differences in activation during local switching effects (switch trials vs. repeat trials, within blocks) have not been ...

For the analyses of dose-relations of radiation-induced chromosome aberrations a weighted least squares method has to be carried out since the variance of observed aberration yields are different at different doses. Consequently identical statistical weights have to be used for the comparison of dose-response functions. For this reason ...

Information from imaging and diffraction planes, or real and reciprocal spaces, of transmission electron microscopes (TEM) can be combined using iterative transformation algorithms to reconstruct the complex wave function, to improve image resolution and to remove residual aberrations in the case of aberration corrected TEM. Here, we ...

Spherical aberration limits the ability of a human eye to form a clear image. The amount of Spherical Aberration found in a given eye is different across a population and is actively changing as a function of accommodation, light level, and age. Any attempt made to correct spherical aberration will need to have an ...

Third-order aberrations at the first and the second focus planes of double focus Wien filters are derived in terms of the following electric and magnetic field components--dipole: E1, B1; quadrupole: E2, B2; hexapole: E3, B3 and octupole: E4, B4. The aberration coefficients are expressed under the second-order geometrical aberration ...

Executive functions deficits are among the most frequently reported symptoms of autism spectrum disorders (ASDs), however, there have been few functional magnetic resonance imaging (fMRI) studies that investigate the neural substrates of executive functions deficits in ASDs, and only one in adolescents. The current study examined ...

Recent neuroimaging research has shown sex-related differences in the relationship between brain structure and cognitive function. Anatomical studies have shown a greater reliance for cognitive function on white matter structure in adult females, and a greater reliance on gray matter structure in adult males. Functional neuroimaging ...

Murine monoclonal antibodies (mAbs) are widely used but have limitations if administered in humans. The use of chimeric or humanized mAbs can reduce immunogenicity. The first step in producing such mAbs is to clone murine variable genes from a hybridoma, but it is possible to amplify both functional and aberrant variable genes, as they coexist in the ...

Interferometric synthetic aperture microscopy (ISAM) reconstructs the scattering potential of a sample with spatially invariant resolution, based on the incident beam profile, the beam scan pattern, the physical model of light sample interaction, and subsequent light collection by the system. In practice, aberrations may influence the beam profile, particularly at higher NA, ...

We study the effects of primary spherical aberration on the three-dimensional point spread function (PSF) of the two-color (two-photon) excitation (2CE) (2PE) fluorescence microscope with two confocal excitation beams that are separated by an angle ?. The two excitation wavelengths ?1 and ?2 are related to the single-photon excitation wavelength ?e by: ...

Chromosomal aberration production was studied in V-79 Chinese hamster tissue culture cells by uv light administered during the post-DNA-synthetic G/sub 2/ phase of the cell cycle. The treatment produced achromatic lesions ond some chromatid deletions in the first post-irradiation mitosis, but no isochromatid deletions or chromatid exchange oberrations. In contrast, ...

Many factors of intracavity perturbation will degrade the output power and beam quality for high power passive Q-switched slab laser. In the paper, the experiment test on the output beam quality of a passive Q-switched zig-zag slab Nd:YAG laser has been performed by adopting Hartmann-Shack (H-S) wavefront sensor and Zernike mode reconstruction theory. In this way, the PV and RMS values of the ...

A novel deformable mirror using 52 independent magnetic actuators (MIRAO 52, Imagine Eyes) is presented and characterized for ophthalmic applications. The capabilities of the device to reproduce different surfaces, in particular Zernike polynomials up to the fifth order, are investigated in detail. The study of the influence functions of the deformable mirror reveals a ...

Evidence from lesion and cortical-slice studies implicate the neocortical cholinergic system in the modulation of sensory, attentional and memory processing. In this review we consider findings from sixty-three healthy human cholinergic functional neuroimaging studies that probe interactions of cholinergic drugs with brain activation profiles, and relate these to contemporary ...

The modulation transfer function (MTF) and the corresponding point spread function is defined for an imaging system and the relation to detector size and optical aberration is explained. An analytical expression for the combined effect of pixel size and a...

The transfer function of an ideal reticle with an aberration is derived by numerical analysis; this transfer function permits the reconstruction of the spectral distribution obtained by a reticulated spectroscope. The role of noise in this process is disc...

Human breast cancer genesis and progression is caused by the aberrant function of genes that positively and negatively regulate aspects of cell proliferation, apoptosis, genome stability, angiogenesis, invasion and metastasis( 1). Discovery and functional...

... 2. Fackenthal JD and Godley LA. (in preparation) Aberrant RNA splicing and its functional consequences in cancer cells. CONCLUSION: ...

The main aim of the present coordinate-based meta-analysis is to identify brain regions that are commonly activated in functional magnetic resonance imaging studies (fMRI) investigating number processing and calculation in children. Here, we include 19 developmental fMRI papers, five of which also examine children diagnosed with developmental dyscalculia and/or mathematical ...

Structural magnetic resonance imaging data from 308 twins, 64 singleton siblings of twins, and 228 singletons were analyzed using structural equation modeling and selected multivariate methods to identify genetically mediated intracortical associations. Principal components analyses (PCA) of the genetic correlation matrix indicated a single factor accounting for over 60% of the genetic variability ...

The aim of this functional magnetic resonance imaging study is to identify neuroanatomical substrates underlying phonological processing of segmental (consonant, rhyme) and suprasegmental (tone) units. An auditory verbal recognition paradigm was employed in which native speakers of Mandarin Chinese were required to match a phonological unit that occurs in a list of three ...

A brain imaging study was conducted in the case of a catatonic type of schizophrenia (DSM-IIIR) by applying (i) positron emission tomography (PET) and (ii) single photon emission computed tomography (SPECT). A PET study using [18F]-2-fluoro-2-deoxy-D-glucose revealed a lower glucose utilization in the dorsal frontal and parietal lobes of both cerebral hemispheres. Correlative SPECT studies using ...

Building on animal and human lesion evidence, neuroimaging studies are increasingly identifying abnormalities in corticolimbic circuits mediating aggressive behavior. This review focuses on three neural systems involved in impulsive/reactive aggression: 1) subcortical neural systems that support the production of aggressive impulses; 2) decision-making circuits and social-emotional information ...

As the industry drives to lower k1 imaging we commonly accept the use of higher NA imaging and advanced illumination conditions. The advent of this technology shift has given rise to very exotic pupil spread functions that have some areas of high thermal energy density creating new modeling and control challenges. Modern scanners are equipped with advanced lens manipulators ...

A filter for aberration correction in medical ultrasound imaging is presented. The filter is optimal in the sense of maximizing the expected energy in a modified beamformer output of the received acoustic backscatter. The situation considered is frequently found in applications when imaging organs through a body wall: aberration is introduced in a layer ...

Aging has readily observable effects on the ability to resolve conflict between competing stimulus attributes that are likely related to selective structural and functional brain changes. To identify age-related differences in neural circuits subserving conflict processing, we combined structural and functional MRI and a Stroop Match-to-Sample task ...

Aging has readily observable effects on the ability to resolve conflict between competing stimulus attributes that are likely related to selective structural and functional brain changes. To identify age-related differences in neural circuits subserving conflict processing, we combined structural and functional MRI and a Stroop Match-to-Sample task ...

Recent research indicates that language processing relies on brain areas dedicated to perception and action. For example, processing words denoting manipulable objects has been shown to activate a fronto-parietal network involved in actual tool use. This is suggested to reflect the knowledge the subject has about how objects are moved and used. However, information about how ...

Egocentric tactile perception is crucial for skilled hand motor control. In order to better understand the brain functional underpinnings related to this basic sensorial perception, we performed a tactile perception functional magnetic resonance imaging (fMRI) experiment with two aims. The first aim consisted of characterizing the neural substrate of two ...

The theory of wavefront analysis of a noncircular wavefront is given and applied for a systematic comparison of the use of annular and Zernike circle polynomials for the analysis of an annular wavefront. It is shown that, unlike the annular coefficients, the circle coefficients generally change as the number of polynomials used in the expansion changes. Although the wavefront fit with a certain ...

PURPOSETo evaluate the influence of spherical aberration on contrast sensitivity using adaptive optics.SETTINGVision Science and Advanced Retinal Imaging Laboratory, Department of Ophthalmology & Vision Science, University of California, Davis Medical Center, Sacramento, California, USA.METHODSContrast sensitivity at 8 cycles per degree was evaluated using an adaptive ...

The incidence of chromosome aberrations in peripheral blood lymphocytes of 197 dockyard workers has been followed over a 10-yr period. These workers were exposed to mixed neutron-gamma radiation during the refuelling of nuclear reactors, but most exposures were below the internationally accepted maximum permissible level of 5 rem per yr. There was a significant increase in ...

Translated from Zh. Tekh. Fiz.; 42: No. 11, 2279-2287(Nov A method which allows determinations of the paraxial propenties of electrostatic axially symmetric mirrors and calculation of the aberration of these mirrors is given. The equations do not contain the time as a parameter. The field distribution functions in the principal optical axis of ...

We demonstrate that a transmission electron microscope fitted with two spherical-aberration correctors can be operated as an energy-filtered scanning confocal electron microscope. A method for establishing this mode is described and initial results showing 3D chemical mapping with nanoscale sensitivity to height and thickness changes in a carbon film are presented. ...

We demonstrate that a transmission electron microscope fitted with two spherical-aberration correctors can be operated as an energy-filtered scanning confocal electron microscope. A method for establishing this mode is described and initial results showing 3D chemical mapping with nanoscale sensitivity to height and thickness changes in a carbon film are presented. ...

A simple geometrical method to measure the aberration of astigmatism present in the wavefront that emerges from a telescope is presented. The method is based on the analysis of the external contour of the image of a slightly defocused star. An expression elliptical edge is obtained, which links the rms value of Z22 to the geometric parameters of the ellipse. This expression is ...

Adolescents spend a significant part of their leisure time watching TV programs and movies that portray violence. It is unknown, however, how the extent of violent media use and the severity of aggression displayed affect adolescents' brain function. We investigated skin conductance responses, brain activation and functional brain connectivity to media ...

AbstractAttention deficit hyperactivity disorder (ADHD) and autism are two neurodevelopmental disorders associated with prominent executive dysfunction, which may be underpinned by disruption within fronto-striatal and fronto-parietal circuits. We probed executive function in these disorders using a sustained attention task with a validated brain-behaviour ...

Neural correlates of working memory (WM) based on the Sternberg Item Recognition Task (SIRT) were assessed in 40 children with moderate-to-severe traumatic brain injury (TBI) compared to 41 demographically-comparable children with orthopedic injury (OI). Multiple magnetic resonance imaging (MRI) methods assessed structural and functional brain correlates of WM, including ...

Rhythm of brain activities represents oscillations of postsynaptic potentials in neocortex, therefore it can serve as an indicator of the brain activity state. In order to check the connectivity of brain rhythm, this paper develops a new method of constructing functional network based on phase synchronization. Electroencephalogram (EEG) data were collected while subjects ...

The importance of quality of vision (QOV) along with quality of life (QOL) in medicine has been recently widely recognized. We have conducted studies to quantitatively analyze factors related to QOV. Irregular astigmatism can be a significant obstacle for achieving satisfactory QOV. Videokeratography data were broken down using Fourier harmonic series analysis into spherical power, regular ...

Chronic marijuana use during adolescence is frequently comorbid with heavy alcohol consumption and associated with CNS alterations, yet the influence of early cannabis and alcohol use on microstructural white matter integrity is unclear. Building on evidence that cannabinoid receptors are present in myelin precursors and affect glial cell processing, and that excessive ethanol exposure is ...

A phase/amplitude mask on the aperture of an imaging system results in a pupil function that is multiplicative with the lens function, resulting in a morphological transformation of the imaging wavefront. It was shown that such amplitude and phase functions can be implemented using polarization masks, with the advantage that the phase ...

... dynamic aberrations. For the dynamic aberration case, elimination of ... dynamic aberrations. For the dynamic aberration case, elimination of ...

Interferon was obtained by injecting mice with virus-containing allantoic fluid from chick embryos. After incubation of L cells with interferon, they were exposed to gamma radiation. The results of experiments to determine the effect of interferon on share of aberrant cells as function of postradiation (300 R) time show that there are no differences in ...

The oxide compositions (OCs) model is established for discussing the chromatic aberrations of a gradient refractive index rod lens. The chromatic aberrations for Na(+)/Li(+), K(+)/Cs(+), and K(+)/Tl(+) ion exchanges are discussed based on the OC model and the Huggins-Sun-Davis (HSD) model. Theoretical results indicate that the function ...

A pinhole diagnostics system has been used to measure beam aberrations as a function of steering angle for an expanded beam at the ANL Neutral Particulate Beam Test Stand. The experiment began with a low-abberation unsteered beam. The horizontal steering angle was varied through the range {plus minus}3.5 mrad, and the vertical steering angle varied though ...

The dose-yield relationships for individual classes of chromosome aberrations were measured for cells irradiated in early S after release from thymidine block. It was found that the yield for asymmetrical chromosome exchanges as a function of dose was quadratic, whereas that for sister unions was linear. These data cannot be reconciled with the ...

We outline a novel method for estimating a fixed aberration that is in the image path but not in the wave-front-sensor (WFS) path of an adaptive optics (AO) imaging system. We accomplish this through a nontraditional application of the Gonsalves [Proc. SPIE 207, 32 (1997)] least-squares phase-diversity technique, using an ensemble of images and WFS data. The diversity phases ...

Research has shown that noncontingent reinforcement (NCR) can be an effective behavior-reduction procedure when based on a functional analysis. The effects of NCR may be a result of elimination of the contingency between aberrant behavior and reinforcing consequences (extinction) or frequent and free access to reinforcers that may reduce the participant's ...

The yields of dicentric and ring chromosomes were recorded during telecobalt therapy for mammary carcinoma. The data were fitted to a power or a quadratic function and were compared with those obtained in patients treated for ankylosing spondylitis and nuclear dockyard workers as well as with the results of an in vitro blood irradiation. As expected, the ...

We discuss a method for the study of the spatial statistics of the ocular aberrations, based on the direct use of the Hartmann-Shack centroid displacements, avoiding the wavefront reconstruction step. Centroid diagrams are introduced as a helpful aid to visualize basic properties of the aberration datasets, and slope-related second-order statistical ...

In a 2{ital N}-pole electromagnetic system, defining the electron optical Hamiltonian function, we have derived both general algebraic expressions (arbitrary {ital N}) and special numerical formulas ({ital N}=3,4,5,6,7) for different aberrations from lower to higher order (i.e., the order of {ital N}{minus}1, {ital N}+1, 2{ital N}{minus}3, 2{ital ...

We propose a new method for ray tracing in the living human eye. It consists of delivering a narrow light pencil from an unexpanded laser beam and recording the integrated energy and position of the aerial image formed by the outgoing beam (after reflection off the retina and passage through the fully open pupil of the eye and camera lens). The lateral displacement of the aerial image is ...

Aberration correted electron microscopy (ACEM) has improved resolution to sub-angstrom regime, which allows us to study materials with light elements, with dopants and defects, and with electronic, magnetic and optical functions. Developments of ACEMs and applications that undertaken in the world are briefly reviewed, being focused particularly on 50 pm ...

We derive a simple to implement method to approximately measure the aberration function for a crystalline specimen from an inline hologram. We demonstrate measurement of aberrations up to third order for a scanning transmission electron microscope from both dynamical simulations and experimental Ronchigrams. This method should allow ...

Treatment of radiobiological data taken with different LET distributions in order to determine the true curve of response versus JET is demonstrated. For chromosomal aberrations in Tradescantia neither the energy average nor the track average LET is appropriate for plotting data. For chromatid aberrations in Tradescantia an empirical fit was ...

We show that phase aberrations in an imaging system can be mitigated using binary-amplitude masks that reduce destructive interference in the image spatial frequency domain. Appropriately designed masks increase the magnitude of the optical transfer function and prevent nulls. This offers a low-cost, transmission-mode alternative to phase correction as ...