bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reading in a Regular Orthography: An fMRI Study Investigating the Role of Visual Familiarity
Authors: Ischebeck Anja , Indefrey Peter , Usui Nobuo , Nose Izuru , Hellwig Frauke , Taira Masato 
Published: June 2004

Abstract
In order to separate the cognitive processes associated with phonological encoding and the use of a visual word form lexicon in reading, it is desirable to compare the processing of words presented in a visually familiar form with words in a visually unfamiliar form. Japanese Kana orthography offers this possibility. Two phonologically equivalent but visually dissimilar syllabaries allow the writing of, for example, foreign loanwords in two ways, only one of which is visually familiar. Familiarly written words, unfamiliarly written words, and pseudowords were presented in both Kana syllabaries (yielding six conditions in total) to participants during an fMRI measurement with a silent articulation task (Experiment 1) and a phonological lexical decision task (Experiment 2) using an event-related design. Consistent over two experimental tasks, the three different stimulus types (familiar, unfamiliar, and pseudoword) were found to activate selectively different brain regions previously associated with phonological encoding and word retrieval or meaning. Compatible with the predictions of the dual-route model for reading, pseudowords and visually unfamiliar words, which have to be read using phonological assembly, caused an increase in brain activity in left inferior frontal regions (BA 44/47), as compared to visually familiar words. Visually familiar and unfamiliar words were found to activate a range of areas associated with lexico-semantic processing more strongly than pseudowords, such as the left and right temporo-parietal region (BA 39/40), a region in the left middle/inferior temporal gyrus (BA 20/21), and the posterior cingulate (BA 31).
Left But Not Right Temporal Involvement in Opaque Idiom Comprehension: A Repetitive Transcranial Magnetic Stimulation Study
Authors: Oliveri Massimiliano , Romero Leonor , Papagno Costanza 
Published: June 2004

Abstract
It has been suggested that figurative language, which includes idioms, is controlled by the right hemisphere. We tested the right hemisphere hypothesis by using repetitive transcranial magnetic stimulation (rTMS) to transiently disrupt the function of the frontal and temporal areas of the right versus left hemisphere in a group of normal participants involved in a task of opaque idiom versus literal sentence comprehension. Forty opaque, nonambiguous idioms were selected. Fifteen young healthy participants underwent rTMS in two sessions. The experiment was run in five blocks, corresponding to the four stimulated scalp positions (left frontal and temporal and right frontal and temporal) and a baseline. Each block consisted of 16 trials—8 trials with idioms and 8 trials with literal sentences. In each trial, the subject was presented with a written sentence, which appeared on the screen for 2000 msec, followed by a pair of pictures for 2500 msec, one of which corresponded to the sentence. The alternative corresponded to the literal meaning for idioms and to a sentence differing in a detail in the case of literal sentences. The subject had to press a button corresponding to the picture matching the string. Reaction times increased following left temporal rTMS, whereas they were unaffected by right hemisphere rTMS, with no difference between idiomatic and literal sentences. Left temporal rTMS also reduced accuracy without differences between the two types of sentences. These data suggest that opaque idiom and literal sentence comprehension depends on the left temporal cortex.
Predicting Success: Patterns of Cortical Activation and Deactivation Prior to Response Inhibition
Authors: Hester Robert L. , Murphy Kevin , Foxe John J. , Foxe Deirdre M. , Javitt Daniel C. , Garavan Hugh 
Published: June 2004

AbstractThe present study investigated the relationships between attention and other preparatory processes prior to a response inhibition task and the processes involved in the inhibition itself. To achieve this, a mixed fMRI design was employed to identify the functional areas activated during both inhibition decision events and the block of trials following a visual cue introduced 2 to 7 sec prior (cue period). Preparing for successful performance produced increases in activation for both the cue period and the inhibition itself in the frontoparietal cortical network. Furthermore, preparation produced activation decreases in midline areas (insula and medial prefrontal) argued to be responsible for monitoring internal emotional states, and these cue period deactivations alone predicted subsequent success or failure. The results suggest that when cues are provided to signify the imminent requirement for behavioral control, successful performance results from a coordinated pattern of preparatory activation in task-relevant areas and deactivation of task-irrelevant ones.
Effects of Strategies on Mental Rotation and Hemispheric Lateralization: Neuropsychological Evidence
Authors: Tomasino Barbara , Rumiati Raffaella I. 
Published: June 2004

Abstract
We can predict how an object would look if we were to see it from different viewpoints by imagining its rotation. This essential human ability, called mental rotation (MR), guides individuals' actions by constantly updating their environmental consequences. It is, however, still under debate whether the way in which our brain accomplishes this operation is dete r mined by the type of stimulus or rather by a mental strategy. Here we present neuropsychological evidence sustaining the view that what matters is the type of strategy adopted in MR. Thus, independently of the type of stimulus, patients with left hemisphere lesions showed a selective deficit in MR as a consequence of their manual activity, whereas patients with right hemisphere lesions were found impaired in MR by means of a visual strategy. We conclude that MR is achieved by recruiting different strategies, implicitly triggered or prompted at will, each sustained by a unilateral brain network.
Multisensory Integration Sites Identified by Perception of Spatial Wavelet Filtered Visual Speech Gesture Information
Authors: Callan Daniel E. , Jones Jeffery A. , Munhall Kevin , Kroos Christian , Callan Akiko M. , Vatikiotis-Bateson Eric 
Published: June 2004

Abstract
Perception of speech is improved when presentation of the audio signal is accompanied by concordant visual speech gesture information. This enhancement is most prevalent when the audio signal is degraded. One potential means by which the brain affords perceptual enhancement is thought to be through the integration of concordant information from multiple sensory channels in a common site of convergence, multisensory integration (MSI) sites. Some studies have identified potential sites in the superior temporal gyrus/sulcus (STG/S) that are responsive to multisensory information from the auditory speech signal and visual speech movement. One limitation of these studies is that they do not control for activity resulting from attentional modulation cued by such things as visual information signaling the onsets and offsets of the acoustic speech signal, as well as activity resulting from MSI of properties of the auditory speech signal with aspects of gross visual motion that are not specific to place of articulation information. This fMRI experiment uses spatial wavelet bandpass filtered Japanese sentences presented with background multispeaker audio noise to discern brain activity reflecting MSI induced by auditory and visual correspondence of place of articulation information that controls for activity resulting from the above-mentioned factors. The experiment consists of a low-frequency (LF) filtered condition containing gross visual motion of the lips, jaw, and head without specific place of articulation information, a midfrequency (MF) filtered condition containing place of articulation information, and an unfiltered (UF) condition. Sites of MSI selectively induced by auditory and visual correspondence of place of articulation information were determined by the presence of activity for both the MF and UF conditions relative to the LF condition. Based on these criteria, sites of MSI were found predominantly in the left middle temporal gyrus (MTG), and the left STG/S (including the auditory cortex). By controlling for additional factors that could also induce greater activity resulting from visual motion information, this study identifies potential MSI sites that we believe are involved with improved speech perception intelligibility.
Consistent Chronostasis Effects across Saccade Categories Imply a Subcortical Efferent Trigger
Authors: Yarrow Kielan , Johnson Helen , Haggard Patrick , Rothwell John C. 
Published: June 2004

Abstract
Saccadic chronostasis refers to the subjective temporal lengthening of the first visual stimulus perceived after an eye movement, and is most commonly experienced as the “stopped clock” illusion. Other temporal illusions arising in the context of movement (e.g., “intentional binding”) appear to depend upon the volitional nature of the preceding motor act. Here we assess chronostasis across different saccade types, ranging from highly volitional (self-timed saccades, antisaccades) to highly reflexive (peripherally cued saccades, express saccades). Chronostasis was similar in magnitude across all these conditions, despite wide variations in their neural bases. The illusion must therefore be triggered by a “lowest common denominator” signal common to all the conditions tested and their respective neural circuits. Specifically, it is suggested that chronostasis is triggered by a low-level signal arising in response to efferent signals generated in the superior colliculus.
Neural Correlates of First-Person Perspective as One Constituent of Human Self-Consciousness
Authors: Vogeley K. , May M. , Ritzl A. , Falkai P. , Zilles K. , Fink G. R. 
Published: June 2004

Abstract
Taking the first-person perspective (1PP) centered upon one's own body as opposed to the third-person perspective (3PP), which enables us to take the viewpoint of someone else, is constitutive for human self-consciousness. At the underlying representational or cognitive level, these operations are processed in an egocentric reference frame, where locations are represented centered around another person's (3PP) or one's own perspective (1PP). To study 3PP and 1PP, both operating in egocentric frames, a virtual scene with an avatar and red balls in a room was presented from different camera viewpoints to normal volunteers (n = 11) in a functional magnetic resonance imaging experiment. The task for the subjects was to count the objects as seen either from the avatar's perspective (3PP) or one's own perspective (1PP). The scene was presented either from a ground view (GV) or an aerial view (AV) to investigate the effect of view on perspective taking. The factors perspective (3PP vs. 1PP) and view (GV vs. AV) were arranged in a two-factorial way. Reaction times were increased and percent correctness scores were decreased in 3PP as opposed to 1PP. To detect the neural mechanisms associated with perspective taking, functional magnetic resonance imaging was employed. Data were analyzed using SPM'99 in each subject and non-parametric statistics on the group level. Activations common to 3PP and 1PP (relative to baseline) were observed in a network of occipital, parietal, and prefrontal areas. Deactivations common to 3PP and 1PP (relative to baseline) were observed predominantly in mesial (i.e., parasagittal) cortical and lateral superior temporal areas bilaterally. Differential increases of neural activity were found in mesial superior parietal and right premotor cortex during 3PP (relative to 1PP), whereas differential increases during 1PP (relative to 3PP) were found in mesial prefrontal cortex, posterior cingulate cortex, and superior temporal cortex bilaterally. The data suggest that in addition to joint neural mechanisms, for example, due to visuospatial processing and decision making, 3PP and 1PP rely on differential neural processes. Mesial cortical areas are involved in decisional processes when the spatial task is solved from one's own viewpoint, whereas egocentric operations from another person's perspective differentially draw upon cortical areas known to be involved in spatial cognition.
Event-Related Potential Correlates of the Retrieval of Emotional and Nonemotional Context
Authors: Smith Adam P. R. , Dolan Raymond J. , Rugg Michael D. 
Published: June 2004

Abstract
In two experiments, we examined event-related potentials (ERPs) elicited in an old/new recognition memory test by emotionally neutral visual objects that, at encoding, had been associated with neutrally, negatively, or positively valenced background contexts. In Experiment 2, subjects also judged the context in which the item had been studied. In Experiment 1, “left parietal” old/new ERP effects were elicited by correctly recognized items. Items encoded in emotional contexts, but not those studied in neutral contexts, elicited additional effects early in the recording epoch over lateral temporal scalp and, later, over left temporo-frontal scalp. In Experiment 2, “left parietal” and “right frontal” ERP effects were elicited by recognized items that attracted correct source judgments. Additional effects, an early lateral temporal positivity and a late-onset, left-sided positivity, were elicited by items studied in emotionally valenced contexts and attracting correct source judgments. Together, the findings indicate that retrieval processing is influenced by the emotional valence of the context in which an item is encoded, regardless of whether contextual information is task relevant.
Shape Saliency Modulates Contextual Processing in the Human Lateral Occipital Complex
Authors: Altmann Christian F. , Deubelius Arne , Kourtzi Zoe 
Published: June 2004

AbstractVisual context influences our perception of target objects in natural scenes. However, little is known about the analysis of context information and its role in shape perception in the human brain. We investigated whether the human lateral occipital complex (LOC), known to be involved in the visual analysis of shapes, also processes information about the context of shapes within cluttered scenes. We employed an fMRI adaptation paradigm in which fMRI responses are lower for two identical than for two different stimuli presented consecutively. The stimuli consisted of closed target contours defined by aligned Gabor elements embedded in a background of randomly oriented Gabors. We measured fMRI adaptation in the LOC across changes in the context of the target shapes by manipulating the position and orientation of the background elements. No adaptation was observed across context changes when the background elements were presented in the same plane as the target elements. However, adaptation was observed when the grouping of the target elements was enhanced in a bottom-up (i.e., grouping by disparity or motion) or top-down (i.e., shape priming) manner and thus the saliency of the target shape increased. These findings suggest that the LOC processes information not only about shapes, but also about their context. This processing of context information in the LOC is modulated by figure–ground segmentation and grouping processes. That is, neural populations in the LOC encode context information when relevant to the perception of target shapes, but represent salient targets independent of context changes.
Involvement of the Superior Temporal Cortex and the Occipital Cortex in Spatial Hearing: Evidence from Repetitive Transcranial Magnetic Stimulation
Authors: Lewald Jörg , Meister Ingo G. , Weidemann Jürgen , Töpper Rudolf 
Published: June 2004

Abstract
The processing of auditory spatial information in cortical areas of the human brain outside of the primary auditory cortex remains poorly understood. Here we investigated the role of the superior temporal gyrus (STG) and the occipital cortex (OC) in spatial hearing using repetitive transcranial magnetic stimulation (rTMS). The right STG is known to be of crucial importance for visual spatial awareness, and has been suggested to be involved in auditory spatial perception. We found that rTMS of the right STG induced a systematic error in the perception of interaural time differences (a primary cue for sound localization in the azimuthal plane). This is in accordance with the recent view, based on both neurophysio-logical data obtained in monkeys and human neuroimaging studies, that information on sound location is processed within a dorsolateral “where” stream including the caudal STG. A similar, but opposite, auditory shift was obtained after rTMS of secondary visual areas of the right OC. Processing of auditory information in the OC has previously been shown to exist only in blind persons. Thus, the latter finding provides the first evidence of an involvement of the visual cortex in spatial hearing in sighted human subjects, and suggests a close interconnection of the neural representation of auditory and visual space. Because rTMS induced systematic shifts in auditory lateralization, but not a general deterioration, we propose that rTMS of STG or OC specifically affected neuronal circuits transforming auditory spatial coordinates in order to maintain alignment with vision.
Severe hemochromatosis in a Portuguese family associated with a new mutation in the 5′-UTR of the HAMP gene
Authors: Matthes Thomas , Aguilar-Martinez Patricia , Pizzi-Bosman Loredana , Darbellay Régis , Rubbia-Brandt Laura , Giostra Emilio , Michel Martine , Ganz Tomas , Beris Photis 
Published: June 2004

Abstract
Juvenile hereditary hemochromatosis is a genetically heterogeneous disorder transmitted as an autosomal recessive trait. It is most often caused by mutations in the HJV gene and rarely in the HAMP gene. Hepcidin is considered to constitute a negative regulator of iron absorption, and its production is increased in inflammatory states and iron overload. We report the detection of a new mutation in the HAMP gene leading to juvenile hemochromatosis in 2 members of a Portuguese family. The mutation lies in the 5′-UTR (untranslated region) of the gene and creates a new initiation codon in the context of a Kozak sequence. We found no trace of hepcidin protein in the patients' urine, suggesting that ribosomes select the mutant initiation codon for translation. The decrease of hepcidin production would thus lead to increased iron absorption, resulting in iron deposition in parenchymal tissues. Phlebotomy therapy of the 2 patients resulted in impressive clinical improvement. (Blood. 2004;104: 2181-2183)
Extended β-globin locus control region elements promote consistent therapeutic expression of a γ-globin lentiviral vector in murine β-thalassemia
Authors: Hanawa Hideki , Hargrove Phillip W. , Kepes Steven , Srivastava Deo K. , Nienhuis Arthur W. , Persons Derek A. 
Published: June 2004

Abstract
Since increased fetal hemoglobin diminishes the severity of β-thalassemia and sickle cell anemia, a strategy using autologous, stem cell–targeted gene transfer of a γ-globin gene may be therapeutically useful. We previously found that a γ-globin lentiviral vector utilizing the β-globin promoter and elements from the β-globin locus control region (LCR) totaling 1.7 kb could correct murine β-thalassemia. However, therapeutic consistency was compromised by chromosomal position effects on vector expression. In contrast, we show here that the majority of animals that received transplants of β-thalassemic stem cells transduced with a new vector containing 3.2 kb of LCR sequences expressed high levels of fetal hemoglobin (17%-33%), with an average vector copy number of 1.3. This led to a mean 26 g/L (2.6 g/dL) increase in hemoglobin concentration and enhanced amelioration of other hematologic parameters. Analysis of clonal erythroid cells of secondary spleen colonies from mice that underwent transplantation demonstrated an increased resistance of the larger LCR vector to stable and variegating position effects. This trend was also observed for vector insertion sites located inside genes, where vector expression was often compromised, in contrast to intergenic sites, where higher levels of expression were observed. These data emphasize the importance of overcoming detrimental position effects for consistent therapeutic globin vector expression.
Mitogenic Action of Calcium-Sensing Receptor on Rat Calvarial Osteoblasts
Authors: Chattopadhyay Naibedya , Yano Shozo , Tfelt-Hansen Jacob , Rooney Paul , Kanuparthi Deepthi , Bandyopadhyay Sanghamitra , Ren Xianghui , Terwilliger Ernest , Brown Edward M. 
Published: June 2004

AbstractThe parathyroid calcium-sensing receptor (CaR) plays a nonredundant role in systemic calcium homeostasis. In bone, Ca2+o, a major extracellular factor in the bone microenvironment during bone remodeling, could potentially serve as an extracellular first messenger, acting via the CaR, that stimulates the proliferation of preosteoblasts and their differentiation to osteoblasts (OBs). Primary digests of rat calvarial OBs express the CaR as assessed by RT-PCR, Northern, and Western blot analysis, and immunocolocalization of the CaR with the OB marker cbfa-1. Real-time PCR revealed a significant increase in CaR mRNA in 5- and 7-d cultures compared with 3-d cultures post harvesting. High Ca2+o did not affect the expression of CaR mRNA during this time but up-regulated cyclin D (D1, D2, and D3) genes, which are involved in transition from the G1 to the S phase of the cell cycle, as well as the early oncogenes, c-fos and early growth response-1; high Ca2+o did not, however, alter IGF-I expression, a mitogenic factor for OBs. The high Ca2+o-dependent increase in the proliferation of OBs was attenuated after transduction with a dominant-negative CaR (R185Q), confirming that the effect of high Ca2+o is CaR mediated. Stimulation of proliferation by the CaR involves the Jun-terminal kinase (JNK) pathway, as high Ca2+o stimulated the phosphorylation of JNK in a CaR-mediated manner, and the JNK inhibitor SP600125 abolished CaR-induced proliferation. Our data, therefore, show that the parathyroid/kidney CaR expressed in rat calvarial OBs exerts a mitogenic effect that involves activation of the JNK pathway and up-regulation of several mitogenic genes.