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PubMedDate not supplied

[Visual evoked potentials in chessboard pattern reversion in children with optic neuritis].

Visual evoked potentials (VEP) to chess pattern reversion were studied in 17 children with optic neurites during the acute stage and in the course of convalescence 1-2 months and 1-3 years after the disease onset. Coarse VEP changes were detected in the patients during the acute stage of optic neuritis. A positive time course of VEP was followed up in late periods after the acute attack of the disease. Despite normalization of vision acuity, no complete restoration of VEP to small-cell chess patterns was seen. The findings evidence that studies of VEP to chess pattern reversion should be carried out to detect subclinical involvement of the optic nerve and to timely diagnose optic neuritis in children.

Acute Disease↗
PubMedDate not supplied

[Studies on cerebral visual evoked potentials in the differential diagnosis of macular edema and obscration amblyopia in children with artiphakia].

The cerebral cortex visual evoked potentials (VEP) to chess pattern reversion have been examined in 41 healthy children (41 eyes) and in 25 children (25 eyes) with artiphakia after traumatic cataract extraction, with macular edemas (ME) in 12 of these and obscuration amblyopia (OA) in 13. Comparison of the amplitude-time parameters of the VEP and of treir relationship with the cell size and the chess pattern contrast has shown a characteristic feature of ME, i. e. an increased peak latency (PL) of the first negative deviation (H1 peak) of the VEP to reversion of the chess pattern with 90% contrast. The mean values of PLHI (M +/- m) have been as follows: 107.1 +/- 3.9 ms in children with ME, 93.1 +/- 2.3 ms in those with OA, and 84.9 +/- 0.8 ms in the controls. An elevation of PLHI over 100ms has been recorded in 9 of the 12 patients with ME and only in 1 child with OA. Involvement of the ganglion cells of the central area of the retina is considered as a possible reason of the detected VEP disorders in ME.

Adolescent↗
PubMedDate not supplied

[Anxiety-related and depressive disorders in women during the premenopausal and menopausal period. Study of the efficacy and acceptability of tianeptine versus maprotiline].

This study was conducted to evaluate the effectiveness and acceptability of Tianeptine (T) versus Maprotiline (M) in the management of anxiodepressive disorders in menopausal and premenopausal women. Anxio-depressive women with a Montgomery Asberg Depression score (MADRS) > 20 and a Hamilton Anxiety score (HARS) > 15 were included in the study. T or M were the only psychotropes taken by the patients during the study. Eighty-three women were enrolled and given, by double blind assignment T 37.5 mg/day or M 75 mg/day (T n = 42; M n = 41). The effectiveness of therapy was assessed on D5, D15, D30 and D60 by the MADRS, HARS, CGI and CHESS scores; acceptability was assessed by the CHESS scale. To exclude placebo responders, the patients were treated with a placebo for 7 days prior to enrollment. A significant improvement in the MADRS score, compared with the previous score, remained until D60 for the T group and M group (p < 0.01). The improvement in the MADRS score was higher (p = 0.025) in the T group than in the M group. At D60, there was a statistically significant difference between T and M in favour of T (p = 0.04). Similar results were obtain with HARS and CGI (item 1). The incidence of side effect was significantly lower in the group treated with T than in the group treated with M. At any time point, there were more patients in the M group (p < 0.001) who complained of side effects than in the T group. The patients were divided into subgroups according to whether or not they were also receiving Hormone Replacement Therapy (HRT). The group taking HRT and T had a more significant reduction in HARS (p = 0.038) and CHESS (p = 0.015) than the group taking T only. T administrated as a single psychotropic agent showed an improvement in the symptoms of anxio-depression which were significantly more important than in the control group with better control of associated complaints.

Antidepressive Agents, Tricyclic↗
PubMed1975

Reflex epilepsy evoked by decision making.

A patient had seizures while playing chess or cards or when filling out complex forms, doing complex mathematical problems, and during certain parts of the neuropsychological testing. Seizures were myoclonic and accompanied and electroencephalographic dysrhythmia of the atypical spike and wave type. Evoked seizures were not related to visual, tactile, or auditory stimuli or clues. In chess, seizures occurred when he was on the defense and threatened. Simple decision making or physiologic stress did not evoke seizures nor did nonsequential decision making under verbal pressure. Evoking factors were complex decision making in a sequential fashion and with an element of stress or concern regarding the outcome of the decision making. Stimulus was usually nonverbal. Three major factors--decision complexity, sequential factor, and related stress or concern--may have some reciprocal relationships.

Adult↗
PubMed1999

Off-resonance metabolite magnetization transfer measurements on rat brain in situ.

Off-resonance metabolite magnetization transfer (MT) experiments were performed on rat brain in vivo and post mortem, with short (18 msec) and long (144 msec) echo-time 1H nuclear magnetic resonance (NMR) spectroscopy. In vivo and post mortem, the methyl protons of total creatine and all protons from glutamate/glutamine showed a strong MT effect on off-resonance saturation, as well as the methyl protons from lactate post mortem. Other resonances, like that of A-acetyl aspartate, showed a much smaller, but detectable, MT effect. The results obtained were confirmed by combining off-resonance saturation with two-dimensional correlation spectroscopy. Three water suppression techniques, i.e., presaturation, chemical shift-selective (CHESS), and selective water eliminated Fourier transform (WEFT) were evaluated for their ability to generate an MT effect, to assess their possible influence on metabolite quantification. Presaturation and selective WEFT led to alterations of the total creatine, lactate, and N-acetyl aspartate resonance intensities, while CHESS had no effect. Finally, it was shown that water protons play an important role in the generation of the observed metabolite MT effects.

Animals↗
PubMedDate not supplied

Fat suppression at 7T using a surface coil: application of an adiabatic half-passage chemical shift selective radiofrequency pulse.

The selective suppression of fat using chemical shift selective (CHESS) sinc, gaussian presaturation, or binomial radiofrequency pulses are widely implemented techniques in magnetic resonance imaging. For applications wherein transmitter coils that generate inhomogeneous magnetic (B1), fields are used (e.g., surface coils), adiabatic radiofrequency pulses that are less susceptible to spatial variations in B1 amplitude will improve the spatial homogeneity of spin excitation angle. Herein, we describe the application of an adiabatic half-passage hyperbolic secant CHESS pulse suitable for acquiring fat-suppressed magnetic resonance images with surface coils on high-field systems. Images obtained from a water/fat phantom and from the abdominal region of a rat are presented indicating excellent suppression of fat signal from the entire coil-sensitive volume.

Abdomen↗
PubMed1986

Multipurpose NMR imaging using stimulated echoes.

STEAM (stimulated-echo acquisition mode) imaging techniques recently introduced by the authors are demonstrated to provide a versatile tool for improving the parametric specificity in NMR imaging. Stimulated echoes can be excited by a sequence of at least three rf pulses with flip angles of 90 degrees or less. The main characteristics of the STEAM method are based on the great functional flexibility of an imaging sequence comprising three rf pulses unequal to 180 degrees and three intervals prior to acquisition of the data. Major advantages are the easy access to contiguous multiplanar images, to CHESS (chemical-shift-selective) images, and to T1 information. Moreover, the rf power deposition is considerably reduced as compared to spin-echo NMR imaging sequences. Here first in vivo results on human extremities are presented including contiguous multislice images, multiple CHESS images, and spin-lattice relaxation time images calculated from a series of simultaneously recorded T1-weighted STEAM images.

Biophysical Phenomena↗
PubMed1997

Improved water and lipid suppression for 3D PRESS CSI using RF band selective inversion with gradient dephasing (BASING).

A T1 insensitive solvent suppression technique-band selective inversion with gradient dephasing (BASING)-was developed to suppress water and lipids for 1H magnetic resonance spectroscopy (MRS). BASING, which consists of a frequency selective RF inversion pulse surrounded by spoiler gradient pulses of opposite signs, was used to dephase stopband resonances and minimally impact passband metabolites. Passband phase linearity was achieved with a dual BASING scheme. Using the Shinnar-Le Roux algorithm, a highpass filter was designed to suppress water and rephase the lactate methyl doublet independently of TE, and water/lipid bandstop filters were designed for the brain and prostate. Phantom and in vivo experimental 3D PRESS CSI data were acquired at 1.5 T to compare BASING with CHESS and STIR suppression. With BASING, the measured suppression factor was over 100 times higher than with CHESS or STIR causing baseline distortions to be removed. It was shown that BASING can be incorporated into a variety of sequences to offer improved suppression in the presence of B1 and T1 inhomogeneites.

Brain Chemistry↗
PubMed1991

Rook's tour representation of the genetic code.

Disconnected recurrences of the stop signal, serine and arginine appear in the original representation of the genetic code, and of the stop signal, arginine, serine and leucine in the codon ring representation. To achieve connectedness along with structural continuity, a rook's tour representation is presented here. On the basis of structural similarities and disparities in their side groups, each of the 20 amino acids is associated with a domain comprised of from one to six contiguous squares on the chess board. As the rook moves on the chess board, it reaches all 64 squares in the ordering of the codon numbers, which prescribe the codons by a simple formula based on the position and size of the nucleotides in a triplet. Recurrences of the stop signal, arginine and serine occur naturally on the tour as the rook enters each of the latter domains for the second time. A mathematical equivalent of the rook's tour may enter as a programming device in the implementation of the code by the RNAs.

Amino Acids↗
PubMed2002

Increase in detrusor wall thickness indicates bladder outlet obstruction (BOO) in men.

Detrusor wall thickness decreases continuously while the bladder fills to 50% of its capacity and then remains constant until 100%. Therefore, detrusor wall measurements were performed in patients when the bladder was filled to maximum capacity only. Mean detrusor wall thickness for unobstructed (n = 14), equivocal (n=23) and obstructed patients (n=33) were 1.33, 1.62 and 2.4 mm, respectively (P <0.001). With increasing CHESS letters and CHESS numbers, the thickness of the detrusor wall increased as well (P< 0.001). The positive predictive value of detrusor wall measurement (95.5% for a cut-off value greater than or equal to 2 mm) was superior to all other predictors investigated. The thickness of the detrusor wall increases depending on the extent of BOO. Both constrictive and compressive BOO lead to an increase in detrusor wall thickness. BOO is found in 95.5% of men with a detrusor wall thickness greater than or equal to 2 mm. Measuring the thickness of the detrusor wall can be used as a screening test to detect BOO.

Adolescent↗
PubMed1993

Reconstructive remembering of the scientific literature.

In this paper we investigate the role of reconstructive memory in citation errors that occur in the scientific literature. We focus on the case of de Groot's (1946) studies of the memory for chess positions by chess experts. Previous work has shown that this research is very often cited incorrectly. In Experiment 1 we show that free recall of this work by research psychologists replicates most of the errors found in the published literature. Experiment 2 shows that undergraduates reading a correct account of the de Groot study also make the same set of errors in recall. We interpret these findings as showing that consistent errors in secondary accounts of experimental findings are frequently reconstructive memory errors due to source confusion and schema-based processes. Analysis of a number of other examples of scientific literature that have been frequently cited incorrectly add additional support to the reconstructive account. We conclude that scientists should be aware of the tendency of reconstructive memory errors to cause violations of the scientific norm of accurate reporting of the scientific literature.

Adult↗
PubMed1995

Controlled comparison of the effects and abrupt discontinuation of buspirone and lorazepam.

1. The purpose of this study was to compare the effects and abrupt discontinuation of buspirone 15 or 20 mg tid and lorazepam 3 or 4 mg tid following 8 weeks of treatment. A total of 43 outpatients with generalized anxiety disorder were included in the study and 39 entered the withdrawal phase. 2. Clinical assessments were performed at baseline, 2, 4, 6 and 8 weeks (active phase) and after 9 and 10 weeks (withdrawal phase). These included the Hamilton anxiety scale, the visual analogue scale, the CHESS 84 (a check list for the evaluation of somatic symptoms) and the Lader tranquilizer withdrawal scale (translated in french). 3. Results show similar efficacy for lorazepam and buspirone during the active phase with a higher significant difference for buspirone on the CHESS 84 in relation with neurovegetatives symptoms: lorazepam D0 :16.30 +/- 3.14 D56: 5.10 +/- 0.93 (p < or = 0.01) buspirone D0 :18.82 +/- 3.4 D56: 4.73 +/- 1.18 (p < or = 0.001) No withdrawal phenomena was observed for both drugs using HAM-A lorazepam D63 :12.59 +/- 2.26 D70: 12.0 +/- 1.75 (p = ns) buspirone D63 :10.05 +/- 1.28 D70: 10.32 +/- 1.82 (p = ns) and the same significant difference using Lader scale: lorazepam D63 :4.44 +/- 0.89 D70: 6.96 +/- 1.28 (p < or = 0.05) buspirone D63 :2.95 +/- 0.66 D70: 4.15 +/- 0.92 (p < or = 0.05). 4. This study confirmed that buspirone was as effective as lorazepam at D56 in monitored outpatients with generalized anxiety disorder.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMedDate not supplied

A comparison of selective saturation and selective echo chemical shift imaging techniques.

We report on a comparative study of two methods of chemical shift imaging which can be used to selectively image fat and water in vivo. Both methods require a B0 field sufficiently homogenous to resolve the methylene and water spectral lines. One method, called CHESS, uses a chemically selective pulse to saturate the unwanted spectral line. The other method, called SECSI, achieves chemical selectivity by using a soft 180 degree RF pulse in forming a spin echo image. Both methods require that the strength of the B1 RF field be accurately calibrated and homogenous. We show by theoretical analysis that the suppression of unwanted spectral lines is sensitive to the first power of B1 errors in the CHESS method but to the second power of B1 errors in the SECSI method. Experiments with phantoms confirmed the expected non linearity of the SECSI method, and showed superior water suppression factors in phantoms with it. Experiments with a large phantom and a living rabbit showed superior results using the SECSI method, and the best results were obtained using a combination of the two techniques.

Adipose Tissue↗
PubMed1992

Fat suppression with an improved selective presaturation pulse.

Chemical shift selective (CHESS) imaging is an efficient and easily implemented technique for suppression of the fat component in clinical images. A Gaussian pulse is widely used as the selective presaturation pulse in the CHESS technique. However, a Gaussian pulse hardly performs well even if the magnetic field is very carefully shimmed. In clinical applications, the fat and water peaks are always inhomogeneously broadened. We have analyzed the performance of the Gaussian pulse in the presence of magnetic field inhomogeneities and present a more efficient selective presaturation pulse developed by applying the conjugate gradient method. The resulting pulse performs well without any requirement for magnetic field homogeneity greater than needed for routine diagnostic MR imaging.

Adipose Tissue↗
PubMed2003

A functional MRI study of high-level cognition. II. The game of GO.

GO is a board game thought to be different from chess in many aspects, most significantly in that GO emphasizes global strategy more than local battle, a property very difficult for computer programs to emulate. To investigate the neural basis of GO, functional magnetic resonance imaging (fMRI) was used to measure brain activities of subjects engaged in playing GO. Enhanced activations were observed in many cortical areas, such as dorsal prefrontal, parietal, occipital, posterior temporal, and primary somatosensory and motor areas. Quantitative analysis indicated a modest degree of stronger activation in right parietal area than in left. This type of right hemisphere lateralization differs from the modest left hemisphere lateralization observed during chess playing.

Brain Mapping↗
PubMed2005

Are gender differences in high achievement disappearing? A test in one intellectual domain.

Males traditionally predominate at upper achievement levels. One general view holds that this is due only to various social factors such as the 'glass ceiling' and lack of female role models. Another view holds that it occurs partly because of innate ability differences, with more males being at upper ability levels. In the last few decades, women have become more achievement focused and competitive and have gained many more opportunities to achieve. The present study examined one intellectual domain, international chess, to quantify its gender differences in achievement and to see if these have been diminishing with the societal changes. Chess is a good test domain because it is a meritocracy, it has objective performance measures, and longitudinal data of a whole population are available. Performance ratings overall and in the top 10, 50 and 100 players of each sex show large gender differences and little convergence over the past three decades, although a few females have become high achievers. The distribution of performance ratings on the January 2004 list shows a higher male mean and evidence for more male variation, just as with traits such as height. Career patterns of players first on the list between 1985 and 1989 show that top males and females entered the list at about the same age but females tend to play fewer games and have shorter careers. In this domain at least, the male predominance is large and has remained roughly constant despite societal changes.

Achievement↗
PubMed2006

IQ, visuospatial ability and the gender divide: a reply to Bilalić and Mcleod.

Bilalic and McLeod's arguments fall short on several grounds. There are excellent logical reasons to expect strong ability/chess expertise links and specific research evidence to date is sparse, with mixed findings. Data are presented from Georgia, which has a high female participation rate in chess, which suggest that differing gender motivation levels and participation rates impact relatively little on chess performance differences at the extreme.

Achievement↗
PubMed2000

Critical Notice.

"Goodness of Fit": Clinical Applications from Infancy through Adult Life. By Stella Chess & Alexander Thomas. Brunner/Mazel, Philadelphia, PA, 1999. pp. 229. pound24.95 (hb). Chess and Thomas's pioneering longitudinal studies of temperamental individuality started over 40 years ago (Thomas et al., 1963). Their publications soon became and remain classics. Their concept of "goodness of fit" emerges out of this monumental work but has had a long gestation period. In their new book, the authors distinguish between behaviour disorders that are reactive to the child's life circumstances, including life events, and which are self-correcting or responsive to the relevant changes in their environment, and more serious disorders.

Journal Article↗