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We examined the underlying mechanisms of the apparent motion illusion of beta movement by obtaining neuromagnetic responses of event-related fields ERFs. A simple setting for visual stimulation of two circles, presented 10i¾? apart horizontally, was used in experiment 1. The first circle, with a duration of 16.7i¾?ms, was followed by the second with three conditions of stimulus-onset-asynchrony: a 16.7i¾?ms, the two circles seen almost simultaneously, b 83.3i¾?ms, perceived optimally as beta movement, and c 549.8i¾?ms occurring isolatedly. In experiment 2, three conditions of real motion for visual stimulation were set: a six circles presented successively for one animation, b 14 circles for one animation, and c 34 circles for one animation. We applied minimum current estimates MCEs to obtain the source activity of the ERFs for beta movement, then calculated an average amplitude for each five 100-ms epoch after the second stimulus onset in experiment 1, and after the first stimulus onset in experiment 2. As the results, the optimal condition showed maximum activities in the first 100-ms epoch at the parietal region in experiment 1, suggesting that the motion components of the MCEs were emerging from this epoch. In experiment 2, three conditions of real motion evoked prolonged MCE activities for the temporal and central areas, suggesting that these components were changed with the "speed" of motion perception. The neuromagnetic activities of beta movement and motion perception may originate from parietal areas within 100i¾?ms after the perception of movement.

Purpose To determine whether there are in vivo differences of γ-aminobutyric acid (GABA) levels in frontal and parietal regions of Alzheimer's disease (AD) patients, compared with healthy controls using magnetic resonance spectroscopy (1H-MRS). Materials and Methods Fifteen AD patients and fifteen age- and gender-matched healthy controls underwent 1H-MRS of the frontal and parietal lobes using the “MEGA-Point Resolved Spectroscopy Sequence” (MEGA-PRESS) technique, and cognitive levels of subjects were evaluated using Mini-Mental State Examination (MMSE) tests. MRS data were processed using the Gannet program. Because the signal detected by MEGA-PRESS includes contributions from GABA, macromolecules and homocarnosine, it is labeled as “GABA+” rather than GABA. Differences of GABA+/Cr ratios between AD patients and controls were tested using covariance analysis, adjusting for gray matter fraction. The relationship between GABA+/Cr and MMSE scores was also analyzed. Results Significant lower GABA+/Cr ratios were found in the parietal region of AD patients compared with controls (P = 0.041). In AD patients, no significant correlations between GABA+/Cr and MMSE scores were found in either the frontal (r = −0.164; P = 0.558) or parietal regions (r = 0.025; P = 0.929). Conclusion Decreased GABA+/Cr levels were present in the parietal region of patients with AD in vivo, suggesting that abnormalities of the GABAergic system may be present in the pathogenesis of AD. J. Magn. Reson. Imaging 2015;41:1326–1331. © 2014 Wiley Periodicals, Inc.

In the classic model of the arrector pili (AP) muscle, each hair follicle is independently associated with a single AP muscle. Recently, new models have been proposed based on interpretations of serial histological cross-sectional images. The purpose of this study was to confirm the morphology of the AP muscle in relation to the follicular unit (FU) using quantitative three-dimensional (3D) reconstruction of serially sectioned images. Skin samples were obtained from the parietal region of the scalp, and processed using routine histological procedures. The serially sectioned slides were stained with Masson's trichrome. All the hairs and hair follicles of the FU exhibited some degree of slanting, with the single AP muscle slanted in the same direction. The distal portion of the AP muscle was divided into branches, as in a bronchial tree. There was branching in the single AP muscle present in the FU, and it was inserted into all the hair follicles of the FU either tightly or loosely. We suggest that the classic anatomy of the AP muscle must be modified with this new model, now confirmed by computer-based 3D reconstruction.

Background: In this study, the magnitude and spatial distribution of theta power in the resting EEG were examined to explore the changes in the neurophysiological status of the alcoholic brain. Some state- and trait-related issues of theta power increases in the EEG of alcoholics were also examined. Methods: Absolute theta (3–7 Hz) power in eyes-closed EEGs of 307 alcohol-dependent subjects and 307 age- and gender-matched unaffected controls were compared by using a repeated-measures ANOVA for the entire region and three subregions (frontal, central, and parietal) separately. Supplementary to the main analysis, the effect of three clinical variables on absolute theta power was examined separately for each gender by using correlation and regression analyses. Gender differences in the theta log power difference between alcoholics and controls were explored by using regional repeated-measures ANOVA. Results: Increased absolute theta power was seen in alcohol-dependent subjects at all scalp locations. The theta log power increase in male alcoholics was prominent at the central and parietal regions and in female alcoholics at the parietal region when compared with the respective matched controls. Correlation of drinking variables with log theta power exhibited no group-specific differences. Conclusions: Increased tonic theta power in the EEG may reflect a deficiency in the information-processing capacity of the central nervous system in alcoholics. The theta power increase may also be an electrophysiological index of the imbalance in the excitation-inhibition homeostasis in the cortex. It is likely that the theta power increase is a trait-related phenomenon and is expressed to differing degrees in the two genders.

Two spectral editing techniques for the simultaneous detection of glutathione (GSH) and lactate (Lac) in the human brain at 3 T are described and evaluated. These methods, ‘sMEGA’ (sinc-MEscher and GArwood) and ‘DEW’ (Double Editing With), were optimized to detect GSH and Lac simultaneously at 3 T using density-matrix simulations and validation in phantoms. Simulations to test for co-edited metabolites within the detected GSH region of the spectrum were also performed. In vivo data were acquired in the midline parietal region of seven subjects using both methods, and compared with conventional MEGA-PRESS (MEscher and GArwood-Point RESolved Spectroscopy) acquisitions of GSH and Lac. Simulations and phantom experiments showed that sMEGA and DEW had a high editing efficiency for both GSH and Lac. In the phantom, the editing efficiency of GSH was >88% relative to a conventional GSH MEGA-PRESS acquisition, whereas, for Lac, the editing efficiency was >95% relative to a conventional Lac MEGA-PRESS acquisition. Simulations also showed that the editing efficiency of both methods was comparable with separate MEGA-PRESS acquisitions of the same metabolites. In addition, simulations and in vivo spectra showed that, at a TE of 140 ms, there was a partial overlap between creatine (Cr) and GSH peaks, and that N-acetyl aspartate/N-acetyl aspartyl glutamate (NAA/NAAG) were sufficiently resolved from GSH. In vivo measurements showed that both sMEGA and DEW edited GSH and Lac reliably with the same editing efficiency as conventional MEGA-PRESS acquisitions of the same metabolites, with measured GSH integrals of 2.23 ± 0.51, 2.31 ± 0.38, 2.38 ± 0.53 and measured Lac integrals of 1.72 ± 0.67, 1.55 ± 0.35 and 1.53 ± 0.54 for MEGA-PRESS, DEW and sMEGA, respectively. Simultaneous detection of GSH and Lac using sMEGA and DEW is possible at 3 T with high editing efficiency.

‘Number sense’ is a short-hand for our ability to quickly understand, approximate, and manipulate numerical quantities. My hypothesis is that number sense rests on cerebral circuits that have evolved specifically for the purpose of representing basic arithmetic knowledge. Four lines of evidence suggesting that number sense constitutes a domain-specific, biologically-determined ability are reviewed: the presence of evolutionary precursors of arithmetic in animals; the early emergence of arithmetic competence in infants independently of other abilities, including language; the existence of a homology between the animal, infant, and human adult abilities for number processing; and the existence of a dedicated cerebral substrate. In adults of all cultures, lesions to the inferior parietal region can specifically impair number sense while leaving the knowledge of other cognitive domains intact. Furthermore, this region is demonstrably activated during number processing. I postulate that higher–level cultural devel-opments in arithmetic emerge through the establishment of linkages between this core analogical representation (the ‘number line’ ) and other verbal and visual representations of number notations. The neural and cognitive organization of those representations can explain why some mathematical concepts are intuitive, while others are so difficult to grasp. Thus, the ultimate foundations of mathematics rests on core representations that have been internalized in our brains through evolution.

Summary The occurrence of an os interparietale was studied in two transparent preparations of fetal red deer (Cervus elaphus) heads and in 14 dried skulls of fetal to early postnatal individuals from four Cervus species (C. elaphus, C. nippon, C. duvauceli and C. eldi). In 14 of the 16 specimens, an interparietal was present as either a paired or single bone. In only a neonate red deer and a 5-week-old sika deer this skull element was missing. We therefore conclude that an os interparietale, developing from paired centres of ossification, is normally present in Cervus species. This clearly distinguishes them from the fallow deer, where an interparietal is missing (Kierdorf and Kierdorf, 1992b). Our findings thus support the view that the fallow deer should be considered a distinct genus Dama instead of being included within Cervus.

This is a follow-up study to earlier investigations on neural tube defects (NTD) in the Kyoto collection of human embryos. It includes an extensive examination of abnormal embryos which have been photographed and serially sectioned following routine histological preparation. Two new types of NTD are described in the parietal region (the roof of the third ventricle) which had previously been overlooked. These anomalies were found most commonly in embryos at the developmental period. Carnegie stage [CS] 16-23 (embryonic days 38-52). Hypotheses are advanced regarding the genesis of NTD and whether encephaloceles and NTD are part of a spectrum of malformation. This study also reinforces evidence that the occurrence of NTD is significantly higher in the embryonic period than at birth. Animal studies, using the guinea-pig are discussed with regard to the investigation of hypotheses put forward to explain the genesis of NTD.

In contrast to the situation in roe deer (Kierdorf and Kierdorf, in press) and other cervid species, an os interparietale was missing in the fallow deer cranium. Absence of this skull element in Dama dama is regarded as an apomorphic character state. The area covered by the interparietals in Capreolus was occupied by the parietals in Dama. This condition (loss of interparietals, enlargement of parietals) is in accord with a trend seen in vertebrate evolution, that is, progressive reduction in the number of skull elements concomitant with enlargement of the remaining bones. Synostosis of the parietals in Dama started a few days post partum and was completed at about 7 to 8 months of age. In males, obliteration of the sutura parietooccipitalis commenced in adult life, whereas in females only closure of the central region of this suture was occasionally observed.

Summary In contrast to the situation in roe deer (Kierdorf and Kierdorf, in press) and other cervid species, an os interparietals was missing in the fallow deer cranium. Absence of this skull element in Dama dama is regarded as an apomorphic character state. The area covered by the interparietals in Capreolus was occupied by the parietals in Dama. This condition (loss of interparietals, enlargement of parietals) is in accord with a trend seen in vertebrate evolution, that is, progressive reduction in the number of skull elements concomitant with enlargement of the remaining bones. Synostosis of the parietals in Dama started a few days post partum and was completed at about 7 to 8 months of age. In males, obliteration of the sutura parietooccipitalis commenced in adult life, whereas in females only closure of the central region of this suture was occasionally observed.

Efferent cortical projections of posterior parietal cortex were determined by degeneration and autoradiographic methods in owl monkeys. Intraregional connections were to the immediate surround of the injection or lesion site, and to distinct foci within the posterior parietal region. The extraregional ipsilateral connections were with (1) previously established subdivisions of visual association cortex (the Dorsomedial Area, the Medial Area, the Dorsolateral Area, and the Middle Temporal Area), (2) other locations in caudal neocortex, and (3) frontal cortex. The callosal projections were to separate foci in posterior parietal cortex of the contralateral cerebral hemisphere. The separate foci of both ipsilateral and contralateral terminations in posterior parietal cortex raise the possibility that this region contains more than one functional subdivision. The connections with visual association cortex suggest a role for parietal cortex in visual behavior. Other foci in caudal neocortex indicate the possible locations of additional subdivisions of association cortex.

Summary Electroenccphalograms recorded from the parietal region of 3 normal subjects and 10 schizophrenic patients were brought under investigation. Changes in the postconvulsive state were devided into 5 stages and, beside the consideration of the expected relation of clinical picture to physiological sleep, narcosis and epileptic disorder, the factor and mechanism for each stage were commented electroenceplialographically. As the effective factors of the electric shock treatment, the narcotic action of electric stimulation and the intensifying of the metabolism in the cerebral tissue were made responsible.

This case must be considered one of suppuration of the petrous pyramid because of the following facts: 1. Following an acute mastoiditis, the development of intense deepseated pain behind the eye, severe pain over the right eye-brow and the parietal region; 2. The sudden profuse discharge of pus from the mastoid wound and to some degree from the external auditory canal; 3. The period of low grade sepsis following the mastoidectomy, until the flare-up of the temperature from the seventh to the tenth day after the first operation, when the inflammation in the petrous pyramid was at its height; 4. The extensively pneumatized development of the mastoid; 5. The roentgenologic findings showing positive evidence of bone destruction at the medial end of the right petron, and further evidence seven months later that there was some regeneration of the bone in this region; and 6. The abatement of the pain in the eye and the sudden improvement of the patient following the operation on his petrous pyramid.

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