scholarly journals Contralateral White Noise Selectively Changes Right Human Auditory Cortex Activity Caused by a FM-Direction Task

2005 ◽  
Vol 93 (1) ◽  
pp. 414-423 ◽  
Author(s):  
Nicole Behne ◽  
Henning Scheich ◽  
André Brechmann
Keyword(s):  
Auditory Cortex ◽  
White Noise ◽  
Hemispheric Specialization ◽  
Critical Role ◽  
Excitatory Input ◽  
Human Studies ◽  
Response Properties ◽  
The Right ◽  
Noise Experiment

Animal and human studies suggest that directional categorization of frequency-modulated (FM) tones (rising vs. falling) is a function of the right auditory cortex (AC). To investigate this hemispheric specialization in more detail, we analyzed both the binaural and monaural representation of FM tones and the influence of contralateral white noise on the processing of FM tone direction. In two fMRI-experiments, FM tones with varied direction, center-frequencies, and duration were presented binaurally or monaurally without contralateral white noise (experiment 1) and with contralateral white noise (experiment 2) while the subjects had to perform the same directional categorization task. In experiment 1, contralateral FM tones led to strongest activation, binaural FM tones to intermediate, and ipsilateral FM tones to weakest activation in each AC. This is in accordance with binaural response properties of neurons in animal AC. In experiment 2, contralateral white noise had no significant effect on the activation of left AC by FM tones, whereas in right AC, it led to a significant increase in activation for ipsilateral FM tones. This result provides further support for the critical role of right AC for directional categorization of FM tones, which for ipsilateral input has to be processed in competition to the excitatory input of white noise via the direct contralateral pathway.

scholarly journals Role of Amygdala-Infralimbic Cortex Circuitry in Glucocorticoid-Induced Facilitation of Auditory Fear Memory Extinction

2021 ◽  
pp. 1-22
Author(s):  
Masoomeh Dadkhah ◽  
◽  
Abbas Ali Vafaei ◽  
Ali Rashidy-Pour ◽  
Parnia Trahomi ◽  
...  
Keyword(s):  
Critical Role ◽  
Fear Memory ◽  
Fear Extinction ◽  
Freezing Behavior ◽  
Extinction Training ◽  
Male Rats ◽  
Memory Extinction ◽  
The Right ◽  
Fear Expression

Purpose: The basolateral amygdala (BLA) and infralimbic area (IL) of medial prefrontal cortex (mPFC) are two inter-connected brain structures that mediate both fear memory expression and extinction. Besides the well-known role of the BLA in the acquisition and expression of fear memory, projections from IL to BLA inhibit fear expression and have a critical role in fear extinction. However, the details of IL-BLA interaction remain unclear. Here, we aimed to investigate the role of functional reciprocal interactions between BLA and IL in mediating fear memory extinction. Methods: Using lidocaine (LID), male rats underwent unilateral or bilateral inactivation of the BLA and then unilateral intra-IL infusion of CORT, prior to extinction training of auditory fear conditioning paradigm. Freezing behavior was reported as an index for the measurement of conditioned fear. Infusions were performed before the extinction training, allowing to examine the effects on fear expression and also further extinction memory. Experiments 1-3 investigated the effects of left or right infusion of CORT into IL, and LID unilaterally into BLA on fear memory extinction. Results: Results showed that intra-IL infusion of CORT in the right hemisphere reduced freezing behavior when administrated before the extinction training. Auditory fear memory extinction was impaired by asymmetric inactivation of BLA and CORT infusion in the right IL; however, the same effect was not observed with symmetric inactivation of BLA. Conclusion: It is concluded that that the IL-BLA neural circuit may provide additional evidence to contribution of this circuit in auditory fear extinction. This study demonstrate dissociable roles for right or left BLA in subserving the auditory fear extinction. Our finding also raise the possibility that left BLA-IL circuitry may contribute in mediating auditory fear memory extinction via underlying mechanisms, however further research is required.

scholarly journals Right Place at the Right Time: How Changes in Protocadherins Affect Synaptic Connections Contributing to the Etiology of Neurodevelopmental Disorders

Cells ◽  
2020 ◽  
Vol 9 (12) ◽  
pp. 2711
Author(s):  
Maria Mancini ◽  
Silvia Bassani ◽  
Maria Passafaro
Keyword(s):  
Cell Adhesion ◽  
Neurodevelopmental Disorders ◽  
Synapse Formation ◽  
Large Fraction ◽  
Critical Role ◽  
Basic Research ◽  
Axon Pathfinding ◽  
Neurite Initiation ◽  
The Right

During brain development, neurons need to form the correct connections with one another in order to give rise to a functional neuronal circuitry. Mistakes during this process, leading to the formation of improper neuronal connectivity, can result in a number of brain abnormalities and impairments collectively referred to as neurodevelopmental disorders. Cell adhesion molecules (CAMs), present on the cell surface, take part in the neurodevelopmental process regulating migration and recognition of specific cells to form functional neuronal assemblies. Among CAMs, the members of the protocadherin (PCDH) group stand out because they are involved in cell adhesion, neurite initiation and outgrowth, axon pathfinding and fasciculation, and synapse formation and stabilization. Given the critical role of these macromolecules in the major neurodevelopmental processes, it is not surprising that clinical and basic research in the past two decades has identified several PCDH genes as responsible for a large fraction of neurodevelopmental disorders. In the present article, we review these findings with a focus on the non-clustered PCDH sub-group, discussing the proteins implicated in the main neurodevelopmental disorders.

Perspectives

1990 ◽  
Vol 15 (4) ◽  
pp. 3-10
Author(s):  
Jayanth R Varma ◽  
N Venkiteswaran
Keyword(s):  
Capital Market ◽  
Economic Activity ◽  
Critical Role ◽  
Regulatory Agencies ◽  
Recent Past ◽  
Positive Direction ◽  
Emerging Trends ◽  
The Government ◽  
The Right

The Indian capital market has shown signs of buoyancy and dynamism in the recent past. There is a very real need, therefore, to nurture and to give positive direction to the emerging trends in this sphere of economic activity. It is in this context that regulatory agencies have a critical role in providing the right kind of support to avoid bunching of issues as well as in protecting investors against manipulation by unscrupulous investors. Have Indian regulatory agencies risen to the occasion by formulating appropriate and adequate policies to facilitate the development of the capital markets in India? In this article, Varma and Venkiteswaran examine the role of Indian regulatory agencies and evaluate the methodology spelt out in the official guidelines for valuation of equity shares made public by the Government of India.

Tactile Discrimination of Direction of Lines in Relation to Hemispheric Specialization

1982 ◽  
Vol 54 (2) ◽  
pp. 655-660 ◽  
Author(s):  
Daniela Brizzolara ◽  
Gianni L. De Nobili ◽  
Giovanni Ferretti
Keyword(s):  
Right Hemisphere ◽  
Hemispheric Specialization ◽  
Line Orientation ◽  
Contralateral Hemisphere ◽  
Tactile Discrimination ◽  
Experimental Procedure ◽  
Left Hand ◽  
The Right ◽  
Exploratory Movements

The role of the right hemisphere in a task of haptic discrimination of line orientation was studied in 16 children aged 7–6 and 16 adults aged 25 yr. The exploratory movements were limited to hand and wrist, since it has been shown that distal movements are mediated by the contralateral hemisphere. A comparison of the performance of the two hands shows a clear superiority of the left hand and inferred right hemisphere in both children and adults. An especial emphasis in the discussion is given to the role of the experimental procedure in enhancing the effect of the hemispheric functional asymmetries.

scholarly journals Functional Topography of Auditory Areas Derived From the Combination of Electrophysiological Recordings and Cortical Electrical Stimulation

2021 ◽  
Vol 15 ◽  
Author(s):  
Agnès Trébuchon ◽  
F.-Xavier Alario ◽  
Catherine Liégeois-Chauvel
Keyword(s):  
Auditory Cortex ◽  
Language Processing ◽  
Hemispheric Specialization ◽  
Posterior Part ◽  
Primary Auditory Cortex ◽  
Epileptic Seizures ◽  
Superior Temporal Gyrus ◽  
Depth Electrodes ◽  
Electrophysiological Recordings ◽  
The Right

The posterior part of the superior temporal gyrus (STG) has long been known to be a crucial hub for auditory and language processing, at the crossroad of the functionally defined ventral and dorsal pathways. Anatomical studies have shown that this “auditory cortex” is composed of several cytoarchitectonic areas whose limits do not consistently match macro-anatomic landmarks like gyral and sulcal borders. The only method to record and accurately distinguish neuronal activity from the different auditory sub-fields of primary auditory cortex, located in the tip of Heschl and deeply buried in the Sylvian fissure, is to use stereotaxically implanted depth electrodes (Stereo-EEG) for pre-surgical evaluation of patients with epilepsy. In this prospective, we focused on how anatomo-functional delineation in Heschl’s gyrus (HG), Planum Temporale (PT), the posterior part of the STG anterior to HG, the posterior superior temporal sulcus (STS), and the region at the parietal-temporal boundary commonly labeled “SPT” can be achieved using data from electrical cortical stimulation combined with electrophysiological recordings during listening to pure tones and syllables. We show the differences in functional roles between the primary and non-primary auditory areas, in the left and the right hemispheres. We discuss how these findings help understanding the auditory semiology of certain epileptic seizures and, more generally, the neural substrate of hemispheric specialization for language.

scholarly journals Hemispheric specialization for communicative processing: neuroimaging data on the role of the right hemisphere

2009 ◽  
Vol 2 (1) ◽  
Author(s):  
Rochele Paz Fonseca ◽  
Lilian Cristine Scherer ◽  
Camila Rosa de Oliveira ◽  
Maria Alice de Mattos Pimenta Parente
Keyword(s):  
Right Hemisphere ◽  
Hemispheric Specialization ◽  
Neuroimaging Data ◽  
The Right

scholarly journals Differential contributions of the two human cerebral hemispheres to action timing

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Anja Pflug ◽  
Florian Gompf ◽  
Muthuraman Muthuraman ◽  
Sergiu Groppa ◽  
Christian Alexander Kell
Keyword(s):  
Auditory Cortex ◽  
Hemispheric Specialization ◽  
Sensory System ◽  
Cerebral Hemispheres ◽  
Finger Tapping ◽  
Beta Oscillations ◽  
Sensory Cortices ◽  
Sensorimotor Interactions ◽  
The Right ◽  
Action Timing

Rhythmic actions benefit from synchronization with external events. Auditory-paced finger tapping studies indicate the two cerebral hemispheres preferentially control different rhythms. It is unclear whether left-lateralized processing of faster rhythms and right-lateralized processing of slower rhythms bases upon hemispheric timing differences that arise in the motor or sensory system or whether asymmetry results from lateralized sensorimotor interactions. We measured fMRI and MEG during symmetric finger tapping, in which fast tapping was defined as auditory-motor synchronization at 2.5 Hz. Slow tapping corresponded to tapping to every fourth auditory beat (0.625 Hz). We demonstrate that the left auditory cortex preferentially represents the relative fast rhythm in an amplitude modulation of low beta oscillations while the right auditory cortex additionally represents the internally generated slower rhythm. We show coupling of auditory-motor beta oscillations supports building a metric structure. Our findings reveal a strong contribution of sensory cortices to hemispheric specialization in action control.

scholarly journals Handedness Does Not Impact Inhibitory Control, but Movement Execution and Reactive Inhibition Are More under a Left-Hemisphere Control

Symmetry ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1602
Author(s):  
Christian Mancini ◽  
Giovanni Mirabella
Keyword(s):  
Left Hemisphere ◽  
Inhibitory Control ◽  
Right Hemisphere ◽  
Dominant Role ◽  
Hemispheric Specialization ◽  
Arm Movement ◽  
Proactive Inhibition ◽  
Stop Signal Task ◽  
The Right

The relationship between handedness, laterality, and inhibitory control is a valuable benchmark for testing the hypothesis of the right-hemispheric specialization of inhibition. According to this theory, and given that to stop a limb movement, it is sufficient to alter the activity of the contralateral hemisphere, then suppressing a left arm movement should be faster than suppressing a right-arm movement. This is because, in the latter case, inhibitory commands produced in the right hemisphere should be sent to the other hemisphere. Further, as lateralization of cognitive functions in left-handers is less pronounced than in right-handers, in the former, the inhibitory control should rely on both hemispheres. We tested these predictions on a medium-large sample of left- and right-handers (n = 52). Each participant completed two sessions of the reaching versions of the stop-signal task, one using the right arm and one using the left arm. We found that reactive and proactive inhibition do not differ according to handedness. However, we found a significant advantage of the right versus the left arm in canceling movements outright. By contrast, there were no differences in proactive inhibition. As we also found that participants performed movements faster with the right than with the left arm, we interpret our results in light of the dominant role of the left hemisphere in some aspects of motor control.

Lateralization of Language

2019 ◽  
pp. 876-906
Author(s):  
Lise Van der Haegen ◽  
Qing Cai
Keyword(s):  
Human Brain ◽  
Speech Processing ◽  
Right Hemisphere ◽  
Hemispheric Specialization ◽  
Unique Contribution ◽  
Language Impaired ◽  
Language Functions ◽  
Hemisphere Dominance ◽  
The Right

It is intriguing that the two brain halves of the human brain look so similar, but are in fact quite different at the anatomical level, and even more so at the functional level. In particular, the highly frequent co-occurrence of right-handedness and left hemisphere dominance of language has led to an abundance of laterality research. This chapter discusses the most important recent finding on laterality (i.e., left or right hemisphere) and degree of hemispheric specialization for speech production, auditory speech processing, and reading. Following a descriptive overview of these three core sub-processes of language, the chapter summarizes possible influences on the lateralization of each, including anatomical, evolutionary, genetic, developmental, and experiential factors, as well as handedness and impairment. It will become clear that language is a heterogeneous cognitive function driven by a variety of underpinning origins. Next, the often-underestimated role of the right hemisphere for language is discussed with respect to prosody and metaphor comprehension, as well as individual differences in the lateralization of healthy and language-impaired brains. Finally, recent insights into the relationship between lateralized language and non-language functions are discussed, highlighting the unique contribution of lateralization research to the growing knowledge of general human brain mechanisms.

The rhetoric of New Zealand's COVID-19 response

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Binh Bui ◽  
Olayinka Moses ◽  
John Dumay
Keyword(s):  
Critical Role ◽  
Decision Makers ◽  
Response Strategy ◽  
Content Type ◽  
Rhetorical Strategy ◽  
The Public ◽  
Government Documents ◽  
The Right ◽  
Public Policy Decisions

PurposeThe authors unpack the critical role of rhetoric in developing and justifying the New Zealand (NZ) government's coronavirus disease 2019 (COVID-19) lockdown strategy.Design/methodology/approachUsing Green's (2004) theory of rhetorical diffusion, the authors analysed government documents and media releases before, during and after the lockdown to reconstruct the government's rationale.FindingsThe blending of kairos (sense of urgency and “right” time to act), ethos (emphasis on “saving lives”), pathos (fear of disruption and death) and selective use of health-based logos (shrinking infection rates), prompted fast initial adoption of the lockdown. However, support for the rhetoric wavered post-lockdown as absence of robust logos became apparent to the public.Research limitations/implicationsThe authors implicate the role of rhetoric in decision-makers’ ability to successfully elicit support for a new practice under urgency and the right moment to act using emotionalisation and moralisation. The assessment of the NZ government's response strategy provides insights decision-makers could glean in developing policies to tame the virus.Practical implicationsThis study’s analysis demonstrates the unsustainability of rhetoric in the absence of reliable information.Originality/valueThe authors demonstrate the consequences of limited (intermittent) evidence and disregard for accounting/accountability data in public policy decisions under a rhetorical strategy.

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