Extinguishing Extinction: Hemispheric Differences in the Modulation of TMS-induced Visual Extinction by Directing Covert Spatial Attention

2012 ◽  
Vol 24 (4) ◽  
pp. 809-818 ◽  
Author(s):  
Nina Bien ◽  
Rainer Goebel ◽  
Alexander T. Sack
Keyword(s):  
Spatial Attention ◽  
Cognitive Neuroscience ◽  
Early Stage ◽  
Hemispheric Lateralization ◽  
Hemispheric Differences ◽  
Behavioral Deficits ◽  
Stage Of Development ◽  
Great Relevance ◽  
Left And Right ◽  
The Right

The topic of spatial attention is of great relevance for researchers in various fields, including neuropsychology, cognitive neuroscience, and cognitive psychology, as well as for clinical practice. Deficits of spatial attentional arising from parietal brain damage remain largely confined to the left visual field. The mechanisms underlying this hemispheric asymmetry are still elusive. We mimicked the neuropsychological syndrome of contralesional extinction by temporarily inducing a spatial attentional bias in healthy volunteers with TMS. We investigated whether directing covert spatial attention could enhance or, more importantly, counteract the resulting behavioral deficits. Although both the left and right parietal TMS induced contralateral extinction, only left hemifield extinction following right parietal TMS was severely aggravated by a competing stimulus in the ipsilesional (right) hemifield. We put forward the hypothesis that an asymmetry with respect to the ability of detaching attention from a distractor is contributing to the right hemispheric lateralization with regard to extinction. On a broader level, we suggest that “virtual patients” might be used for evaluating neuropsychological treatment in an early stage of development, reducing the burden on actual patients.

scholarly journals The rodent hippocampus as a bilateral structure: A review of hemispheric lateralization

2017 ◽  
Author(s):  
Jake T. Jordan
Keyword(s):  
Brain Region ◽  
Spatial Information ◽  
Right Hemisphere ◽  
Neural Substrates ◽  
Hemispheric Lateralization ◽  
Hemispheric Differences ◽  
Functional Lateralization ◽  
Left And Right ◽  
The Right ◽  
Behavior And Cognition

AbstractThe left and right rodent hippocampi exhibit striking lateralization in some of the very neural substrates considered to be critical for hippocampal cognitive function. Despite this, there is an overwhelming lack of consideration for hemispheric differences in studies of the rodent hippocampus. Asymmetries identified so far suggest that a bilateral model of the hippocampus will be essential for an understanding of this brain region, and perhaps of the brain more widely. Although hypotheses have been proposed to explain how the left and right hippocampi contribute to behavior and cognition, these hypotheses have either been refuted by more recent studies or have been limited in the scope of data they explain. Here, I will first review data on human and rodent hippocampal lateralization. The implications of these data suggest that considering the hippocampus as a bilateral structure with functional lateralization will be critical moving forward in understanding the function and mechanisms of this brain region. In exploring these implications, I will then propose a hypothesis of the hippocampus as a bilateral structure. This discrete-continuous (DC) hypothesis proposes that the left and right hippocampi contribute to spatial memory and navigation in a complementary manner. Specifically, the left hemisphere stores spatial information as discrete, salient locations and that the right hemisphere represents space continuously, contributing to route computation and flexible spatial navigation. Consideration of hippocampal lateralization in designing future studies may provide insight into the function of the hippocampus and resolve debates concerning its function.

Hemispheric Differences in the Relationship Between Corticomotor Excitability Changes Following a Fine-Motor Task and Motor Learning

2004 ◽  
Vol 91 (4) ◽  
pp. 1570-1578 ◽  
Author(s):  
Michael I. Garry ◽  
Gary Kamen ◽  
Michael A. Nordstrom
Keyword(s):  
Motor Learning ◽  
Motor Performance ◽  
Fine Motor ◽  
Hemispheric Differences ◽  
Corticomotor Excitability ◽  
Hand Muscles ◽  
Right Hand ◽  
Left And Right ◽  
The Right ◽  
Intrinsic Hand Muscles

Motor performance induces a postexercise increase in corticomotor excitability that may be associated with motor learning. We investigated whether there are hemispheric differences in the extent and/or time course of changes in corticomotor excitability following a manipulation task (Purdue pegboard) and their relationship with motor performance. Single- and paired-pulse (3 ms) transcranial magnetic stimulation (TMS) was used to assess task-induced facilitation of the muscle evoked potential (MEP) and intracortical inhibition (ICI) for three intrinsic hand muscles acting on digits 1, 2, and 5. Fifteen right-handed subjects performed three 30-s pegboard trials with left or right hand in separate sessions. TMS was applied to contralateral motor cortex before and after performance. Number of pegs placed was higher with the right hand, and performance improved (motor learning) with both hands over the three trials. MEP facilitation following performance was short-lasting (<15 min), selective for muscles engaged in gripping the pegs, and of similar magnitude in left and right hands. ICI was reduced immediately following performance with the right hand, but not the left. The extent of MEP facilitation was positively correlated with motor learning for the right hand only. We conclude that the pegboard task induces a selective, short-lasting change in excitability of corticospinal neurons controlling intrinsic hand muscles engaged in the task. Only left hemisphere changes were related to motor learning. This asymmetry may reflect different behavioral strategies for performance improvement with left and right upper limb in this task or hemispheric differences in the control of skilled hand movements.

scholarly journals The Rhinolith—A Possible Differential Diagnosis of a Unilateral Nasal Obstruction

2010 ◽  
Vol 2010 ◽  
pp. 1-4 ◽  
Author(s):  
Detlef Brehmer ◽  
Randolf Riemann
Keyword(s):  
Differential Diagnosis ◽  
Nasal Cavity ◽  
Foreign Bodies ◽  
Early Stage ◽  
Diagnostic Techniques ◽  
Nasal Discharge ◽  
Rare Occurrence ◽  
The Past ◽  
Stage Of Development ◽  
The Right

Rhinoliths are mineralised foreign bodies in the nasal cavity that are a chance finding at anterior rhinoscopy. Undiscovered, they grow appreciably in size and can cause a foul-smelling nasal discharge and breathing problems. Giant nasal stones are now a very rare occurrence, since improved diagnostic techniques, such as endoscopic/microscopic rhinoscopy, now make it possible to identify foreign bodies at an early stage of development. We report the case of a 37-year-old patient who, at the age of 5-6 years, introduced a foreign body, probably a stone, into his right nasal cavity. On presentation, he complained of difficulty in breathing through the right nostril that had persisted for the last 10 years. For the past four years a strong fetid smell from the nose had been apparent to those in his vicinity. Under general anaesthesia, the stone was removed in toto from the right nasal cavity. The possible genesis of the rhinolith is discussed, our case compared with those described in the literature, and possible differential diagnoses are considered.

scholarly journals Hemispheric Lateralization of Pain Processing by Amygdala Neurons

2009 ◽  
Vol 102 (4) ◽  
pp. 2253-2264 ◽  
Author(s):  
Guangchen Ji ◽  
Volker Neugebauer
Keyword(s):  
Receptive Fields ◽  
Hemispheric Lateralization ◽  
Central Nucleus ◽  
Recording Site ◽  
Peripheral Tissues ◽  
Arthritis Induction ◽  
Before And After ◽  
Pain State ◽  
Left And Right ◽  
The Right

Recent biochemical and behavioral data suggest right-hemispheric lateralization of amygdala functions in pain. Our previous electrophysiological studies showed pain-related neuroplasticity in the latero-capsular division of the central nucleus of the amygdala (CeLC) in the right brain hemisphere. Here we determined differences in the processing of pain-related signals in right versus left CeLC neurons. Individual CeLC neurons were recorded extracellularly before and after induction of an arthritis pain state in anesthetized rats. Brief innocuous and noxious test stimuli were applied to peripheral tissues ipsi- and contralateral to the recording site. A monoarthritis was induced in the ipsi- or contralateral knee by intraarticular injections of kaolin and carrageenan. Under normal conditions, CeLC neurons in the left amygdala had smaller receptive fields than those in the right, but the magnitude of background and evoked activity was not significantly different. After arthritis induction, neurons in the right, but not left, CeLC developed increased background activity and evoked responses, irrespective of the location of the arthritis (ipsi- or contralateral to the recording site). A protein kinase A (PKA) inhibitor decreased the activity of right CeLC neurons after arthritis induction but had no effect in the left amygdala. Forskolin, however, increased the activity of left and right CeLC neurons under normal conditions. The results show for the first time laterality of pain-related electrophysiological activity changes in individual amygdala neurons. Whereas both left and right amygdala neurons receive nociceptive inputs and can become sensitized in principle, a yet unknown mechanism prevents PKA activation and pain-related changes in the left amygdala.

scholarly journals W oczekiwaniu na wykonanie art. 23 TFUE i art. 35 TUE – wciąż niepełne prawo obywateli Unii Europejskiej do opieki dyplomatycznej i konsularnej

2020 ◽  
Vol 29 (5) ◽  
pp. 149
Author(s):  
Krzysztof Kozłowski
Keyword(s):  
International Law ◽  
Early Stage ◽  
Qualitative Change ◽  
Maastricht Treaty ◽  
Member States ◽  
Stage Of Development ◽  
Treaty Law ◽  
Legal Position ◽  
The Right

<p>In 1992, with the adoption of the Maastricht Treaty, a new institution, namely EU citizenship, was created. The treaty introduced a qualitative change in the sphere of political and legal position of citizens of the Member States, who gained in these spheres a number of new powers. One of them is the right to diplomatic and consular protection. The analysis of these two rights leads to a conclusion about the great discrepancy that exists between treaty guarantees and the effective exercise of this right. The Member States did not agree with third countries on this subject, which is a requirement of international law. Secondary law also allows only a partial exercise of the treaty’s right to care in the territory of third countries. It has been reduced only to consular assistance and is still narrowly understood. The treaty law of EU citizens remains therefore at a very early stage of development.</p>

Semantic Networks in the Divided Cerebral Hemispheres

1995 ◽  
Vol 6 (4) ◽  
pp. 212-218 ◽  
Author(s):  
Alice Cronin-Golomb
Keyword(s):  
Right Hemisphere ◽  
Semantic Networks ◽  
Size Composition ◽  
Strongly Correlated ◽  
Hemispheric Differences ◽  
Semantic Organization ◽  
Left And Right ◽  
The Right ◽  
Or Organization ◽  
Visual Hemifields

Hemispheric differences in the recognition and manipulation of meaning may be based on distinctions in size, composition, or organization of the right and left semantic networks The present study describes these features of pictorially based semantic networks in 3 subjects with complete forebrain commissurotomy Stimuli were presented for prolonged viewing to the left and right visual hemifields For each trial, the subjects chose from a 20-choice array all pictures that were associated with a target, then indicated the member of each pair of chosen associates that was more closely related to the target The hemispheres' networks were found to be of similar size and composition, but were organized differently The right hemisphere more often produced linear rankings of semantic associates to a target than did the left, and rankings by the two hemispheres were not strongly correlated Hemispheric differences in semantic organization mirror differences in perceptual organization, with the right hemisphere specialized for conventional meaning and the left hemisphere specialized for detecting and processing deviations from standard meaning

Selective Attention to Faces in a Rapid Visual Stream: Hemispheric Differences in Enhancement and Suppression of Category-selective Neural Activity

2018 ◽  
Vol 30 (3) ◽  
pp. 393-410 ◽  
Author(s):  
Genevieve Quek ◽  
Dan Nemrodov ◽  
Bruno Rossion ◽  
Joan Liu-Shuang
Keyword(s):  
Selective Attention ◽  
Left Hemisphere ◽  
Right Hemisphere ◽  
Hemispheric Differences ◽  
Face Categorization ◽  
The Face ◽  
Left And Right ◽  
The Right ◽  
The Impact ◽  
Selective Activity

In daily life, efficient perceptual categorization of faces occurs in dynamic and highly complex visual environments. Yet the role of selective attention in guiding face categorization has predominantly been studied under sparse and static viewing conditions, with little focus on disentangling the impact of attentional enhancement and suppression. Here we show that attentional enhancement and suppression exert a differential impact on face categorization supported by the left and right hemispheres. We recorded 128-channel EEG while participants viewed a 6-Hz stream of object images (buildings, animals, objects, etc.) with a face image embedded as every fifth image (i.e., OOOOFOOOOFOOOOF…). We isolated face-selective activity by measuring the response at the face presentation frequency (i.e., 6 Hz/5 = 1.2 Hz) under three conditions: Attend Faces, in which participants monitored the sequence for instances of female faces; Attend Objects, in which they responded to instances of guitars; and Baseline, in which they performed an orthogonal task on the central fixation cross. During the orthogonal task, face-specific activity was predominantly centered over the right occipitotemporal region. Actively attending to faces enhanced face-selective activity much more evidently in the left hemisphere than in the right, whereas attending to objects suppressed the face-selective response in both hemispheres to a comparable extent. In addition, the time courses of attentional enhancement and suppression did not overlap. These results suggest the left and right hemispheres support face-selective processing in distinct ways—where the right hemisphere is mandatorily engaged by faces and the left hemisphere is more flexibly recruited to serve current tasks demands.

scholarly journals Formation and Development of Investigation of Misdemeanours as a Form of Pre-trial Investigation in Ukraine (the 18th–19th Centuries)

2021 ◽  
Vol 6 ◽  
pp. 28-37
Author(s):  
Volodymyr Galagan ◽  
Mykola Yakovenko
Keyword(s):  
Early Stage ◽  
Stage Of Development ◽  
Literary Sources ◽  
Wide Range ◽  
Long Time ◽  
The Russian Empire ◽  
The Moment ◽  
The Individual ◽  
The Right ◽  
Modern Form

The article deals with the preconditions of differentiation of forms of pre-trial investigation in Ukraine in the 18th–19th centuries. The concept of investigation of misdemeanours as a form of pre-trial investigation at different stages of social development are considered. The base source of the Russian Empire is examined, with the aspects of using of the term “investigation of misdemeanours” in law enforcement practice thoroughly covered. It is established that this term at the legislative level and in the literary sources held for a long time is subject to transformation in terms of its functional direction. The paper offers a description of the study of the early stage of development and a comparison with the modern form of pre-trial investigation. It is established that at all stages of its development there is a common feature: the provision of a simplified order.The article presents the key differences between the knowledge at the early stage of its creation and the modern form of pre-trial investigation. However, the investigation of misdemeanours starts from the moment of the illegal act until the end of the pre-trial investigation. At first, this investigation of misdemeanours had few signs of research verification. The collected materials were examined by the proceedings and could not be determined by full evidence without appropriate “legalization” procedures. The investigation of misdemeanours had not clearly defined a procedural form and was not limited to specific deadlines, and depended almost entirely on the inner convictions of the individual who conducted this knowledge. In the legislation of the pre-revolutionary period, the investigation of misdemeanours should be carried out by a wide range of authorized persons (police ranks, military and civilian authorities, clergy, government officials, village elders, and others). The investigation of misdemeanours was carried out in everything without exception of crime, regardless of its severity at those times.It is proved that the modern model of pre-trial investigation represents the positive historical experience and the right opinion. Today we can observe a consistent procedure of the implementation of the exercise, a special circle of authorized persons, and the introduction of a balance of appropriate differentiation of forms of pre-trial investigation.

scholarly journals Transection of the ventral hippocampal commissure impairs spatial reference but not contextual or spatial working memory

2021 ◽  
Vol 29 (1) ◽  
pp. 29-37
Author(s):  
Jake T. Jordan ◽  
Yi Tong ◽  
Carolyn L. Pytte
Keyword(s):  
Working Memory ◽  
Learning And Memory ◽  
Spatial Working Memory ◽  
Hemispheric Lateralization ◽  
Long Term Memory ◽  
Substrate Stability ◽  
Short And Long Term ◽  
Left And Right ◽  
The Right

Plasticity is a neural phenomenon in which experience induces long-lasting changes to neuronal circuits and is at the center of most neurobiological theories of learning and memory. However, too much plasticity is maladaptive and must be balanced with substrate stability. Area CA3 of the hippocampus provides such a balance via hemispheric lateralization, with the left hemisphere dominant in providing plasticity and the right specialized for stability. Left and right CA3 project bilaterally to CA1; however, it is not known whether this downstream merging of lateralized plasticity and stability is functional. We hypothesized that interhemispheric convergence of input from these pathways is essential for integrating spatial memory stored in the left CA3 with navigational working memory facilitated by the right CA3. To test this, we severed interhemispheric connections between the left and right hippocampi in mice and assessed learning and memory. Despite damage to this major hippocampal fiber tract, hippocampus-dependent navigational working memory and short- and long-term memory were both spared. However, tasks that required the integration of information retrieved from memory with ongoing navigational working memory and navigation were impaired. We propose that one function of interhemispheric communication in the mouse hippocampus is to integrate lateralized processing of plastic and stable circuits to facilitate memory-guided spatial navigation.

scholarly journals Lateralization of face processing in the human brain

2012 ◽  
Vol 279 (1735) ◽  
pp. 2052-2061 ◽  
Author(s):  
Ming Meng ◽  
Tharian Cherian ◽  
Gaurav Singal ◽  
Pawan Sinha
Keyword(s):  
Face Processing ◽  
Inhibitory Influence ◽  
Hemispheric Differences ◽  
Response Dynamics ◽  
Activation Patterns ◽  
Face Selectivity ◽  
Left And Right ◽  
The Right ◽  
Processing Mechanisms

Are visual face processing mechanisms the same in the left and right cerebral hemispheres? The possibility of such ‘duplicated processing’ seems puzzling in terms of neural resource usage, and we currently lack a precise characterization of the lateral differences in face processing. To address this need, we have undertaken a three-pronged approach. Using functional magnetic resonance imaging, we assessed cortical sensitivity to facial semblance, the modulatory effects of context and temporal response dynamics. Results on all three fronts revealed systematic hemispheric differences. We found that: (i) activation patterns in the left fusiform gyrus correlate with image-level face-semblance, while those in the right correlate with categorical face/non-face judgements. (ii) Context exerts significant excitatory/inhibitory influence in the left, but has limited effect on the right. (iii) Face-selectivity persists in the right even after activity on the left has returned to baseline. These results provide important clues regarding the functional architecture of face processing, suggesting that the left hemisphere is involved in processing ‘low-level’ face semblance, and perhaps is a precursor to categorical ‘deep’ analyses on the right.

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