scholarly journals A circuit motif in the zebrafish hindbrain for a two alternative behavioral choice to turn left or right

eLife ◽  
2016 ◽  
Vol 5 ◽  
Author(s):  
Minoru Koyama ◽  
Francesca Minale ◽  
Jennifer Shum ◽  
Nozomi Nishimura ◽  
Chris B Schaffer ◽  
...  

Animals collect sensory information from the world and make adaptive choices about how to respond to it. Here, we reveal a network motif in the brain for one of the most fundamental behavioral choices made by bilaterally symmetric animals: whether to respond to a sensory stimulus by moving to the left or to the right. We define network connectivity in the hindbrain important for the lateralized escape behavior of zebrafish and then test the role of neurons by using laser ablations and behavioral studies. Key inhibitory neurons in the circuit lie in a column of morphologically similar cells that is one of a series of such columns that form a developmental and functional ground plan for building hindbrain networks. Repetition within the columns of the network motif we defined may therefore lie at the foundation of other lateralized behavioral choices.

2016 ◽  
Vol 113 (52) ◽  
pp. E8492-E8501 ◽  
Author(s):  
Roland G. Benoit ◽  
Daniel J. Davies ◽  
Michael C. Anderson

Imagining future events conveys adaptive benefits, yet recurrent simulations of feared situations may help to maintain anxiety. In two studies, we tested the hypothesis that people can attenuate future fears by suppressing anticipatory simulations of dreaded events. Participants repeatedly imagined upsetting episodes that they feared might happen to them and suppressed imaginings of other such events. Suppressing imagination engaged the right dorsolateral prefrontal cortex, which modulated activation in the hippocampus and in the ventromedial prefrontal cortex (vmPFC). Consistent with the role of the vmPFC in providing access to details that are typical for an event, stronger inhibition of this region was associated with greater forgetting of such details. Suppression further hindered participants’ ability to later freely envision suppressed episodes. Critically, it also reduced feelings of apprehensiveness about the feared scenario, and individuals who were particularly successful at down-regulating fears were also less trait-anxious. Attenuating apprehensiveness by suppressing simulations of feared events may thus be an effective coping strategy, suggesting that a deficiency in this mechanism could contribute to the development of anxiety.


2019 ◽  
Vol 23 (4) ◽  
pp. 448-455
Author(s):  
U. S. Drozd ◽  
E. V. Shaburova ◽  
N. N. Dygalo

The serotonergic system is one of the most important neurotransmitter systems that take part in the regulation of vital CNS functions. The understanding of its mechanisms will help scientists create new therapeutic approaches to the treatment of mental and neurodegenerative diseases and find out how this neurotransmitter system interacts with other parts of the brain and regulates their activity. Since the serotonergic system anatomy and functionality are heterogeneous and complex, the best tools for studying them are based on manipulation of individual types of neurons without affecting neurons of other neurotransmitter systems. The selective cell control is possible due to the genetic determinism of their functions. Proteins that determine the uniqueness of the cell type are expressed under the regulation of cell-specific promoters. By using promoters that are specific for genes of the serotonin system, one can control the expression of a gene of interest in serotonergic neurons. Here we review approaches based on such promoters. The genetic models to be discussed in the article have already shed the light on the role of the serotonergic system in modulating behavior and processing sensory information. In particular, genetic knockouts of serotonin genes sert, pet1, and tph2 promoted the determination of their contribution to the development and functioning of the brain. In addition, the review describes inducible models that allow gene expression to be controlled at various developmental stages. Finally, the application of these genetic approaches in optogenetics and chemogenetics provided a new resource for studying the functions, discharge activity, and signal transduction of serotonergic neurons. Nevertheless, the advantages and limitations of the discussed genetic approaches should be taken into consideration in the course of creating models of pathological conditions and developing pharmacological treatments for their correction.


SLEEP ◽  
2020 ◽  
Author(s):  
Kun-Hsien Chou ◽  
Pei-Lin Lee ◽  
Chih-Sung Liang ◽  
Jiunn-Tay Lee ◽  
Hung-Wen Kao ◽  
...  

Abstract Study Objectives While insomnia and migraine are often comorbid, the shared and distinct neuroanatomical substrates underlying these disorders and the brain structures associated with the comorbidity are unknown. We aimed to identify patterns of neuroanatomical substrate alterations associated with migraine and insomnia comorbidity. Methods High-resolution T1-weighted images were acquired from subjects with insomnia, migraine, and comorbid migraine and insomnia, respectively, and healthy controls (HC). Direct group comparisons with HC followed by conjunction analyses identified shared regional gray matter volume (GMV) alterations between the disorders. To further examine large-scale anatomical network changes, a seed-based structural covariance network (SCN) analysis was applied. Conjunction analyses also identified common SCN alterations in two disease groups, and we further evaluated these shared regional and global neuroanatomical signatures in the comorbid group. Results Compared with controls, patients with migraine and insomnia showed GMV changes in the cerebellum and the lingual, precentral, and postcentral gyri (PCG). The bilateral PCG were common GMV alteration sites in both groups, with decreased structural covariance integrity observed in the cerebellum. In patients with comorbid migraine and insomnia, shared regional GMV and global SCN changes were consistently observed. The GMV of the right PCG also correlated with sleep quality in these patients. Conclusion These findings highlight the specific role of the PCG in the shared pathophysiology of insomnia and migraine from a regional and global brain network perspective. These multilevel neuroanatomical changes could be used as potential image markers to decipher the comorbidity of the two disorders.


2021 ◽  
pp. 147-155
Author(s):  
Mark Selikowitz

All the medicines used to treat ADHD aim to normalize the amount of neurotransmitter in the frontal lobes of the brain. Each child with ADHD needs medication that is selected with care and based on several considerations. Medicine can potentially reduce many difficulties experienced by children with ADHD, although some may not need medication. This chapter discusses medicines in the treatment of ADHD, including how they work, how to find the right medicine for a particular child and aspects of ADHD that are helped by medicines (learning, behaviour, social skills, emotional state). It also covers the place of medicine in the treatment of ADHD, treatment of ADHD without medication, and how to explain the role of medications to a child.


1995 ◽  
Vol 73 (2) ◽  
pp. 246-254 ◽  
Author(s):  
Chantal Bard ◽  
Michelle Fleury ◽  
Normand Teasdale ◽  
Jacques Paillard ◽  
Vincent Nougier

The absence of muscular proprioception, whether at a segmental or at a central level, impairs performance in several ways. The contribution of proprioception to movement control and learning is not easily dissociated from that of other sources of sensory information (e.g., vision). Therefore, the rare clinical cases of extensive neuropathy, depriving the brain massively and permanently of its presumed main sources of dynamogenic information from skin and muscles, are of very special interest. Two such patients and controls were tested in experiments investigating (i) force production, (ii) amplitude coding, (iii) spatial reference frames in pointing, and (iv) prismatic adaptation. Overall, our results highlight the key role of proprioceptive afferents for calibrating the spatial motor frame of reference, and the powerful substitutive properties of the central nervous system.Key words: proprioception, deafferentation, space calibration, motor control.


2019 ◽  
Author(s):  
J. Shashi Kiran Reddy ◽  
Georg Northoff

Antón-Bolaños et al. (2019) report a newly identified neural pathway mechanism, where the patterned spontaneous activity regulates the excitability of a neural network essential for the formation and maintenance of functional sensory maps in the brain. Findings from the study suggest that the patterned spontaneous activity prevalent during the embryonic development of the brain; at the early stages of innervation to the cortex, contributes to the formation of these sensory maps. Synesthesia is a neural phenomenon caused by the unusual links between sensory information, where synesthetic subjects demonstrate atypical functional and neural connectivity caused by the differences in cortical wiring during brain development. So, based on the findings from Antón-Bolaños et al. (2019), one can anticipate the role of spontaneous activity in promoting synesthetic condition. Thus, it will be interesting to study, if the intrinsic spontaneous activity influences the differential cortical wiring and the formation of sensory maps in synesthesia.


2020 ◽  
Author(s):  
Matteo Saponati ◽  
Jordi Garcia-Ojalvo ◽  
Enrico Cataldo ◽  
Alberto Mazzoni

AbstractThe thalamus is a key element of sensory transmission in the brain, as all sensory information is processed by the thalamus before reaching the cortex. The thalamus is known to gate and select sensory streams through a modulation of its internal activity in which spindle oscillations play a preponderant role, but the mechanism underlying this process is not completely understood. In particular, how do thalamocortical connections convey stimulus-driven information selectively over the background of thalamic internally generated activity (such as spindle oscillations)? Here we investigate this issue with a spiking network model of connectivity between thalamus and primary sensory cortex reproducing the local field potential of both areas. We found two features of the thalamocortical dynamics that filter out spindle oscillations: i) spindle oscillations are weaker in neurons projecting to the cortex, ii) the resonance dynamics of cortical networks selectively blocks frequency in the range encompassing spindle oscillations. This latter mechanism depends on the balance of the strength of thalamocortical connections toward excitatory and inhibitory neurons in the cortex. Our results pave the way toward an integrated understanding of the sensory streams traveling between the periphery and the cortex.


2013 ◽  
Vol 11 (2) ◽  
pp. 31-35
Author(s):  
Oleg Aleksandrovich Yarosh

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.


eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Louise P Kirsch ◽  
Sahba Besharati ◽  
Christina Papadaki ◽  
Laura Crucianelli ◽  
Sara Bertagnoli ◽  
...  

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.


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