scholarly journals Parietal area BA7 integrates motor programs for reaching, grasping, and bimanual coordination

2017 ◽  
Vol 117 (2) ◽  
pp. 624-636 ◽  
Author(s):  
Ada Le ◽  
Michael Vesia ◽  
Xiaogang Yan ◽  
J. Douglas Crawford ◽  
Matthias Niemeier
Keyword(s):  
Bimanual Coordination ◽  
Right Hemisphere ◽  
Brodmann Area ◽  
Reach To Grasp ◽  
Area 7 ◽  
Left And Right ◽  
Human Participants ◽  
The Right ◽  
The Brain

Skillful interaction with the world requires that the brain uses a multitude of sensorimotor programs and subroutines, such as for reaching, grasping, and the coordination of the two body halves. However, it is unclear how these programs operate together. Networks for reaching, grasping, and bimanual coordination might converge in common brain areas. For example, Brodmann area 7 (BA7) is known to activate in disparate tasks involving the three types of movements separately. Here, we asked whether BA7 plays a key role in integrating coordinated reach-to-grasp movements for both arms together. To test this, we applied transcranial magnetic stimulation (TMS) to disrupt BA7 activity in the left and right hemispheres, while human participants performed a bimanual size-perturbation grasping task using the index and middle fingers of both hands to grasp a rectangular object whose orientation (and thus grasp-relevant width dimension) might or might not change. We found that TMS of the right BA7 during object perturbation disrupted the bimanual grasp and transport/coordination components, and TMS over the left BA7 disrupted unimanual grasps. These results show that right BA7 is causally involved in the integration of reach-to-grasp movements of the two arms. NEW & NOTEWORTHY Our manuscript describes a role of human Brodmann area 7 (BA7) in the integration of multiple visuomotor programs for reaching, grasping, and bimanual coordination. Our results are the first to suggest that right BA7 is critically involved in the coordination of reach-to-grasp movements of the two arms. The results complement previous reports of right-hemisphere lateralization for bimanual grasps.

Bihemispheric Language: How the Two Hemispheres Collaborate in the Processing of Language

2004 ◽  
Author(s):  
Norman D. Cook
Keyword(s):  
Language Processing ◽  
Right Hemisphere ◽  
Central Question ◽  
Linguistic Processing ◽  
Figures Of Speech ◽  
Language Functions ◽  
Left And Right ◽  
Level Of Understanding ◽  
The Right

Speech production in most people is strongly lateralized to the left hemisphere (LH), but language understanding is generally a bilateral activity. At every level of linguistic processing that has been investigated experimentally, the right hemisphere (RH) has been found to make characteristic contributions, from the processing of the affective aspects of intonation, through the appreciation of word connotations, the decoding of the meaning of metaphors and figures of speech, to the understanding of the overall coherency of verbal humour, paragraphs and short stories. If both hemispheres are indeed engaged in linguistic decoding and both processes are required to achieve a normal level of understanding, a central question concerns how the separate language functions on the left and right are integrated. This chapter reviews relevant studies on the hemispheric contributions to language processing and the role of interhemispheric communications in cognition.

An Exploratory TMS Study on Prefrontal Lateralization in Valence Categorization of Facial Expressions

2017 ◽  
Vol 64 (4) ◽  
pp. 282-289 ◽  
Author(s):  
Chiara Ferrari ◽  
Lucile Gamond ◽  
Marcello Gallucci ◽  
Tomaso Vecchi ◽  
Zaira Cattaneo
Keyword(s):  
Facial Expressions ◽  
Emotional Processing ◽  
Right Hemisphere ◽  
Control Site ◽  
Emotional Facial Expressions ◽  
Left Dlpfc ◽  
Dorsolateral Prefrontal ◽  
Left And Right ◽  
The Right

Abstract. Converging neuroimaging and patient data suggest that the dorsolateral prefrontal cortex (DLPFC) is involved in emotional processing. However, it is still not clear whether the DLPFC in the left and right hemisphere is differentially involved in emotion recognition depending on the emotion considered. Here we used transcranial magnetic stimulation (TMS) to shed light on the possible causal role of the left and right DLPFC in encoding valence of positive and negative emotional facial expressions. Participants were required to indicate whether a series of faces displayed a positive or negative expression, while TMS was delivered over the right DLPFC, the left DLPFC, and a control site (vertex). Interfering with activity in both the left and right DLPFC delayed valence categorization (compared to control stimulation) to a similar extent irrespective of emotion type. Overall, we failed to demonstrate any valence-related lateralization in the DLPFC by using TMS. Possible methodological limitations are discussed.

Bias for the Left Visual Field in Rapid Serial Visual Presentation: Effects of Additional Salient Cues Suggest a Critical Role of Attention

2015 ◽  
Vol 27 (2) ◽  
pp. 266-279 ◽  
Author(s):  
Kamila Śmigasiewicz ◽  
Dariusz Asanowicz ◽  
Nicole Westphal ◽  
Rolf Verleger
Keyword(s):  
Visual Field ◽  
Left Visual Field ◽  
Right Hemisphere ◽  
Critical Role ◽  
Visual Presentation ◽  
The Other ◽  
Early Posterior Negativity ◽  
Left And Right ◽  
The Right

Everyday experience suggests that people are equally aware of stimuli in both hemifields. However, when two streams of stimuli are rapidly presented left and right, the second target (T2) is better identified in the left hemifield than in the right hemifield. This left visual field (LVF) advantage may result from differences between hemifields in attracting attention. Therefore, we introduced a visual cue shortly before T2 onset to draw attention to one stream. Thus, to identify T2, attention was correctly positioned with valid cues but had to be redirected to the other stream with invalid ones. If the LVF advantage is caused by differences between hemifields in attracting attention, invalid cues should increase, and valid cues should reduce the LVF advantage as compared with neutral cues. This prediction was confirmed. ERP analysis revealed that cues evoked an early posterior negativity, confirming that attention was attracted by the cue. This negativity was earlier with cues in the LVF, which suggests that responses to salient events are faster in the right hemisphere than in the left hemisphere. Valid cues speeded up, and invalid cues delayed T2-evoked N2pc; in addition, valid cues enlarged T2-evoked P3. After N2pc, right-side T2 evoked more sustained contralateral negativity than left T2, least long-lasting after valid cues. Difficulties in identifying invalidly cued right T2 were reflected in prematurely ending P3 waveforms. Overall, these data provide evidence that the LVF advantage is because of different abilities of the hemispheres in shifting attention to relevant events in their contralateral hemifield.

scholarly journals The role of neurotransmitter systems separate the hemispheres of the brain in action the new antiepileptic compounds AGB-31

2013 ◽  
Vol 11 (2) ◽  
pp. 31-35
Author(s):  
Oleg Aleksandrovich Yarosh
Keyword(s):  
Nitric Oxide ◽  
Left Hemisphere ◽  
Glutamic Acid Decarboxylase ◽  
Right Hemisphere ◽  
Reduced Glutathione ◽  
Acid Decarboxylase ◽  
Decarboxylase Activity ◽  
The Right ◽  
The Brain

Compound AGB-31, a monocarbamate derivative, is shown to possess a high antiepileptic activity. The mechanisms of antiepileptic action are connected with significant increase in glutamic acid decarboxylase activity in the left hemisphere of the brain, with trend of the glutamate content decrease in the left hemisphere and the tendency to increase GABA in both hemispheres. AGB-31 significantly (more than 3-fold) increases syntase nitric oxide activity in the left hemisphere and has a tendency to reduce the NO content in both hemispheres. AGB-31 significantly (by 63.4%), reduced glutathione peroxydase activity in the right hemisphere without changing it in the left, with a tendency to increase the activity of glutathione reductase in both hemispheres.

scholarly journals Damage to the right insula disrupts the perception of affective touch

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Louise P Kirsch ◽  
Sahba Besharati ◽  
Christina Papadaki ◽  
Laura Crucianelli ◽  
Sara Bertagnoli ◽  
...  
Keyword(s):  
Right Hemisphere ◽  
Anterior Insula ◽  
Affective Touch ◽  
Cortical Organization ◽  
Touch Perception ◽  
Posterior Insula ◽  
The Right ◽  
Tactile System ◽  
The Brain

Specific, peripheral C-tactile afferents contribute to the perception of tactile pleasure, but the brain areas involved in their processing remain debated. We report the first human lesion study on the perception of C-tactile touch in right hemisphere stroke patients (N = 59), revealing that right posterior and anterior insula lesions reduce tactile, contralateral and ipsilateral pleasantness sensitivity, respectively. These findings corroborate previous imaging studies regarding the role of the posterior insula in the perception of affective touch. However, our findings about the crucial role of the anterior insula for ipsilateral affective touch perception open new avenues of enquiry regarding the cortical organization of this tactile system.

Troubles de l'orientation spatiale dans une épreuve de recherche d'itinéraire lors des lésions corticales unilaterales

Perception ◽  
1972 ◽  
Vol 1 (3) ◽  
pp. 325-330 ◽  
Author(s):  
H Hécaen ◽  
C Tzortzis ◽  
M C Masure
Keyword(s):  
Right Hemisphere ◽  
Parietal Lobe ◽  
Cortical Lesions ◽  
Route Finding ◽  
Left And Right ◽  
The Right ◽  
Better Than ◽  
Parietal Lesion

Previous studies on brain-damaged patients have shown impairments in orientation. When the results have been based on a route-finding test the impairment was found in both left and right parietal lesion groups, while when maze tests have been used, the impairment correlated clearly only with lesions of the right hemisphere. In the present study the route-finding test was given to 77 right-handed patients with unilateral cortical lesions (33 right-sided, and 44 left-sided), and to 24 controls. In order to evaluate the possible influence of kinesthetic afferents, the test was carried out under two different conditions: active (walking) and passive (in a pushchair). The results show the performances of subjects with lesions on the left side are significantly poorer than those of the controls, but better than those of subjects with lesions on the right side. For both groups the impairment associated with the lesion is the same under active and passive conditions, which does not support the hypothesis of the possible role of the kinesthetic afferents. Posterior lesions produce significantly more failures in both groups. The importance of the parietal lobe, however, was clearly seen only in subjects with lesions on the right side.

Role of Anterior and Posterior Attention Networks in Hemispheric Asymmetries during Lexical Decisions

1991 ◽  
Vol 3 (4) ◽  
pp. 313-321 ◽  
Author(s):  
Atsuko Nakagawa
Keyword(s):  
Left Hemisphere ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Reaction Times ◽  
Attention Networks ◽  
Priming Task ◽  
Left And Right ◽  
The Right ◽  
Prime Target

The role of the left and right hemisphere was examined during semantic priming by antonyms, remote associates, and unrelated words. Targets presented directly to the left hemisphere showed an early facilitation and a late developing inhibition, while targets presented directly to the right hemisphere showed a late developing facilitation of strong and weak associations and little evidence of inhibition. When a visual cue was given prior to each target word, reaction times were facilitated equally in both visual fields and for all prime target relationships. When the priming task was combined with shadowing, reaction times generally increased and all evidence of inhibition in left hemisphere processing disappeared. This supported the idea that the inhibition found in the left hemisphere was due to its interaction with the anterior attention network.

scholarly journals Behavioural lateralisation in reindeer

Rangifer ◽  
2002 ◽  
Vol 22 (1) ◽  
pp. 51 ◽  
Author(s):  
Yngve Espmark ◽  
Knut Kinderås
Keyword(s):  
Rangifer Tarandus ◽  
Right Hemisphere ◽  
Experimental Studies ◽  
Reindeer Husbandry ◽  
Average Group ◽  
Left And Right ◽  
The Right ◽  
Free Ranging ◽  
The Brain ◽  
Average Group Size

Reindeer (Rangifer tarandus) kept in corrals or otherwise forced to clump typically start milling in response to stressing events. This behaviour is generally considered to have an antipredator effect. An inquiry on herd behaviour, to which 35 Norwegian reindeer husbandry districts responded, showed that 32 experienced that corralled rein¬deer consistently circled leftwards, whereas the remaining three reported consistently rightward circling. Regular monitoring of a reindeer herd in central Norway over a two-year period (1993-94), and experimental studies on a fraction of the same herd, revealed the following traits. Free-ranging reindeer showed no right- or left-turning preference during grazing or browsing, but when the reindeer were driven into corrals or forced to clump in the open they invariably rotated leftwards. The circling of corralled reindeer was triggered at an average group size of 20 to 25 animals, apparently independently of the age and sex of the animals. When they dug craters in the snow to reach food, the reindeer used their left foreleg significantly more often than their right. In 23 out of 35 reindeer, the right hemisphere of the brain was heavier than the left. However, in the sample as a whole, the weights of the left and right hemispheres did not differ significantly. Lateralised behaviour in reindeer is thought to be determined by natural and stress induced asymmetries in brain structure and hormonal activity. In addition, learning is probably important for passing on the behaviour between herd members and generations. Differences in lateralised behaviour between nearby herds are thought to be related primarily to different exposure to stress and learning, whereas genetical and environmental fac¬tors (e.g. diet), age structure and sex ratio are probably more important for explaining differences between distant pop¬ulations.

scholarly journals Role of frontal cortex in inferential reasoning: Evidence from the Word Context Test

2005 ◽  
Vol 11 (4) ◽  
pp. 426-433 ◽  
Author(s):  
KATRINA KEIL ◽  
JULIANA BALDO ◽  
EDITH KAPLAN ◽  
JOEL KRAMER ◽  
DEAN C. DELIS
Keyword(s):  
Right Hemisphere ◽  
Prior Experience ◽  
Special Role ◽  
Inferential Reasoning ◽  
Discourse Comprehension ◽  
Frontal Lobe Lesions ◽  
Word Context ◽  
Left And Right ◽  
The Right

Problem: Inferential reasoning in language involves the ability to deduce information based on context and prior experience. This ability has been generally studied as a right-hemisphere function. Recent research, however, has suggested that inferencing involves anterior regions of both the left and right hemispheres. Methods: We further explored this idea by testing a group of non-aphasic, focal frontal patients (right and left hemisphere) on a new test of inferencing, the Word Context Test. The Word Context Test requires examinees to identify the meaning of a made-up word (e.g., prifa) based on its use in a series of sentences. Findings: Patients with frontal lobe lesions were significantly impaired on this task relative to a group of age- and education-matched controls. Contrary to earlier research focusing on a special role for the right hemisphere in inferencing, there was considerable overlap in performance of right- and left-frontal patients, with right-frontal patients performing better. Conclusions: These findings suggest that inferencing is disrupted following focal frontal injury and have implications for discourse comprehension in non-aphasic patients. (JINS, 2005, 11, 426–433.)

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