scholarly journals Neural signatures of syntactic variation in speech planning

PLoS Biology ◽  
2021 ◽  
Vol 19 (1) ◽  
pp. e3001038
Author(s):  
Sebastian Sauppe ◽  
Kamal K. Choudhary ◽  
Nathalie Giroud ◽  
Damián E. Blasi ◽  
Elisabeth Norcliffe ◽  
...  
Keyword(s):  
Time Course ◽  
Sentence Comprehension ◽  
Gaze Behavior ◽  
Syntactic Variation ◽  
Sentence Planning ◽  
Neural Processes ◽  
Theta Frequency ◽  
Production Flexibility ◽  
Speech Planning ◽  
The Brain

Planning to speak is a challenge for the brain, and the challenge varies between and within languages. Yet, little is known about how neural processes react to these variable challenges beyond the planning of individual words. Here, we examine how fundamental differences in syntax shape the time course of sentence planning. Most languages treat alike (i.e., align with each other) the 2 uses of a word like “gardener” in “the gardener crouched” and in “the gardener planted trees.” A minority keeps these formally distinct by adding special marking in 1 case, and some languages display both aligned and nonaligned expressions. Exploiting such a contrast in Hindi, we used electroencephalography (EEG) and eye tracking to suggest that this difference is associated with distinct patterns of neural processing and gaze behavior during early planning stages, preceding phonological word form preparation. Planning sentences with aligned expressions induces larger synchronization in the theta frequency band, suggesting higher working memory engagement, and more visual attention to agents than planning nonaligned sentences, suggesting delayed commitment to the relational details of the event. Furthermore, plain, unmarked expressions are associated with larger desynchronization in the alpha band than expressions with special markers, suggesting more engagement in information processing to keep overlapping structures distinct during planning. Our findings contrast with the observation that the form of aligned expressions is simpler, and they suggest that the global preference for alignment is driven not by its neurophysiological effect on sentence planning but by other sources, possibly by aspects of production flexibility and fluency or by sentence comprehension. This challenges current theories on how production and comprehension may affect the evolution and distribution of syntactic variants in the world’s languages.

scholarly journals Psilocybin-induced changes in brain network integrity and segregation correlate with plasma psilocin level and psychedelic experience

2021 ◽  
Author(s):  
Martin K. Madsen ◽  
Dea S. Stenbæk ◽  
Albin Arvidsson ◽  
Sophia Armand ◽  
Maja R. Marstrand-Joergensen ◽  
...  
Keyword(s):  
Time Course ◽  
Subjective Experience ◽  
Brain Network ◽  
Executive Control Network ◽  
Neural Processes ◽  
Dorsal Attention Network ◽  
Induced Changes ◽  
Serotonin 2A ◽  
The Brain ◽  
Insight Into

AbstractThe emerging novel therapeutic psilocybin produces psychedelic effects via engagement of cerebral serotonergic targets by psilocin (active metabolite). The serotonin 2A receptor critically mediates these effects by altering distributed neural processes that manifest as increased entropy, reduced functional connectivity (FC) within discrete brain networks (i.e., reduced integrity) and increased FC between networks (i.e., reduced segregation). Reduced integrity of the default mode network (DMN) is proposed to play a particularly prominent role in psychedelic phenomenology, including perceived ego-dissolution. Here, we investigate the effects of a psychoactive oral dose of psilocybin (0.2-0.3 mg/kg) on plasma psilocin level (PPL), subjective drug intensity (SDI) and their association in fifteen healthy individuals. We further evaluate associations between these measures and resting-state FC, measured with functional magnetic resonance imaging, acquired over the course of five hours after psilocybin administration. We show that PPL and SDI correlate negatively with measures of network integrity (including DMN) and segregation, both spatially constrained and unconstrained. We also find that the executive control network and dorsal attention network desegregate, increasing connectivity with other networks and throughout the brain as a function of PPL and SDI. These findings provide direct evidence that psilocin critically shapes the time course and magnitude of changes in the cerebral functional architecture and subjective experience following psilocybin administration. Our findings provide novel insight into the neurobiological mechanisms underlying profound perceptual experiences evoked by this emerging transnosological therapeutic and implicate the expression of network integrity and segregation in the psychedelic experience and consciousness.

Language Functions in the Brain: From Auditory Input to Sentence Comprehension

2017 ◽  
Author(s):  
Angela D. Friederici ◽  
Noam Chomsky
Keyword(s):  
Language Comprehension ◽  
Medial Temporal Lobe ◽  
Time Course ◽  
Sentence Comprehension ◽  
Brain Regions ◽  
Auditory Input ◽  
Thematic Role ◽  
Complex Sentences ◽  
Pitch Information ◽  
The Brain

Chapter 1 presents the neurocognitive model of language comprehension with its functional processing components and processing steps from auditory input to comprehension. The different functional components in the model are described with respect to their brain location and their time course. Topics covered include the identification of language-relevant sounds in speech input; the role of the temporal gyri together with the medial temporal lobe and the hippocampus in access to the lexicon and information encoded in the lexical entry; the combinatorics of language elements; neuroscientific studies relevant for the initial phrase structure building as assumed by syntax-first models; syntactic computation and the processing of syntactically complex sentences; the network of brain regions that support semantic processes; thematic role assignment (i.e., “who is doing what to whom”); and linguistic prosody and the processing of pitch information. Finally, the chapter concludes with a coherent view and respective model of the brain basis of language comprehension, with respect to the neuroanatomy of the brain regions supporting syntactic, semantic, and syntactic processes as well as the temporal relation and interaction of these different functions as comprehension proceeds.

scholarly journals The Orofacial Somatosensory System Is Modulated During Speech Planning and Production

2020 ◽  
Vol 63 (8) ◽  
pp. 2637-2648
Author(s):  
Brianna J. McGuffin ◽  
Julie M. Liss ◽  
Ayoub Daliri
Keyword(s):  
Time Course ◽  
Somatosensory System ◽  
Silent Reading ◽  
Staircase Method ◽  
Lower Lip ◽  
Reading Condition ◽  
Speech Planning ◽  
Detection Ratio ◽  
The Brain ◽  
Perceptual Threshold

Purpose In our previous studies, we showed that the brain modulates the auditory system, and the modulation starts during speech planning. However, it remained unknown whether the brain uses similar mechanisms to modulate the orofacial somatosensory system. Here, we developed a novel behavioral paradigm to (a) examine whether the somatosensory system is modulated during speech planning and (b) determine the somatosensory modulation's time course during planning and production. Method Participants ( N = 20) completed two experiments in which we applied electrical current stimulation to the lower lip to induce somatosensory sensation. In the first experiment, we used a staircase method (one-up, four-down) to determine each participant's perceptual threshold at rest (i.e., the stimulus that the participant detected on 85% of trials). In the second experiment, we estimated each participant's detection ratio of electrical stimuli (with a magnitude equivalent of their perceptual threshold) delivered at various time points before speaking and during a control condition (silent reading). Results We found that the overall detection ratio in the silent reading condition remained unchanged relative to the detection ratio at rest. Approximately 536 ms before speech onset, the detection ratio in the speaking condition was similar to that in the silent reading condition; however, the detection ratio in the speaking condition gradually started to decrease and reached its lowest level at 58 ms before speech onset. Conclusions Overall, we provided compelling behavioral evidence that, as the speech motor system prepares speech movements, it also modulates the orofacial somatosensory system in a temporally specific manner.

Morphological Changes in the Brain of Acutely Ill and Weight-Recovered Patients with Anorexia Nervosa

2014 ◽  
Vol 42 (1) ◽  
pp. 7-18 ◽  
Author(s):  
Jochen Seitz ◽  
Katharina Bühren ◽  
Georg G. von Polier ◽  
Nicole Heussen ◽  
Beate Herpertz-Dahlmann ◽  
...  
Keyword(s):  
Anorexia Nervosa ◽  
Cognitive Deficits ◽  
Time Course ◽  
Morphological Changes ◽  
Meta Analysis ◽  
Short Term ◽  
Clinical Prognosis ◽  
Qualitative Review ◽  
Brain Changes ◽  
The Brain

Objective: Acute anorexia nervosa (AN) leads to reduced gray (GM) and white matter (WM) volume in the brain, which however improves again upon restoration of weight. Yet little is known about the extent and clinical correlates of these brain changes, nor do we know much about the time-course and completeness of their recovery. Methods: We conducted a meta-analysis and a qualitative review of all magnetic resonance imaging studies involving volume analyses of the brain in both acute and recovered AN. Results: We identified structural neuroimaging studies with a total of 214 acute AN patients and 177 weight-recovered AN patients. In acute AN, GM was reduced by 5.6% and WM by 3.8% compared to healthy controls (HC). Short-term weight recovery 2–5 months after admission resulted in restitution of about half of the GM aberrations and almost full WM recovery. After 2–8 years of remission GM and WM were nearly normalized, and differences to HC (GM: –1.0%, WM: –0.7%) were no longer significant, although small residual changes could not be ruled out. In the qualitative review some studies found GM volume loss to be associated with cognitive deficits and clinical prognosis. Conclusions: GM and WM were strongly reduced in acute AN. The completeness of brain volume rehabilitation remained equivocal.

scholarly journals Conceptual and Practical Issues in the Pharmacological Treatment of Brain Injury

1993 ◽  
Vol 4 (3) ◽  
pp. 227-237 ◽  
Author(s):  
Donald G. Stein ◽  
Marylou M. Glasier ◽  
Stuart W. Hoffman
Keyword(s):  
Central Nervous System ◽  
Brain Injury ◽  
Time Course ◽  
Chemical Activity ◽  
Behavioral Testing ◽  
Naturally Occurring ◽  
New Information ◽  
Definition Of ◽  
Injury And Repair ◽  
The Brain

It is only within the last ten years that research on treatment for central nervous system (CNS) recovery after injury has become more focused on the complexities involved in promoting recovery from brain injury when the CNS is viewed as an integrated and dynamic system. There have been major advances in research in recovery over the last decade, including new information on the mechanics and genetics of metabolism and chemical activity, the definition of excitotoxic effects and the discovery that the brain itself secretes complex proteins, peptides and hormones which are capable of directly stimulating the repair of damaged neurons or blocking some of the degenerative processes caused by the injury cascade. Many of these agents, plus other nontoxic naturally occurring substances, are being tested as treatment for brain injury. Further work is needed to determine appropriate combinations of treatments and optimum times of administration with respect to the time course of the CNS disorder. In order to understand the mechanisms that mediate traumatic brain injury and repair, there must be a merging of findings from neurochemical studies with data from intensive behavioral testing.

Еnactivist Criticism of the Neurobiological Theory of Consciousness

2021 ◽  
pp. 76-80
Author(s):  
Anastasia O. Shabalina ◽  
Keyword(s):  
Philosophy Of Mind ◽  
Point Of View ◽  
Science Methods ◽  
Neural Processes ◽  
Neural Substrate ◽  
Critical Revision ◽  
Concept Of Information ◽  
The Mind ◽  
The Brain ◽  
Person Experience

The article considers the main arguments against the neurobiological theory of consciousness from the point of view of the enactivist approach within the philosophy of mind. The neurobiological theory of consciousness, which reduces consciousness to neural activity, is currently the dominant approach to the mind-body problem. The neurobiological theory emerged as a result of advances in research on the phenomena of consciousness and through the development of technologies for visualizing the internal processes of mind. However, at the very heart of this theory, there is a number of logical contradictions. The non-reductive enactivist approach to consciousness, introduced in this article, contributes to the existing argumentation against the reduction of consciousness to neural processes with remonstrations that take into account the modern neuroscientific data. The article analyzes the argumentation of the sensorimotor enactivism developed by A. Noe and offers the account of the teleosemantic approach to the concept of information provided by R. Cao. The key problems of the neurobiological theory of consciousness are highlighted, and the objections emerging within the framework of the enactivist approach are analyzed. Since the main concepts on which the neural theory is based are the concepts of neural substrate, cognition as representation, and information as a unit of cognition, the author of the article presents three key enactivist ideas that oppose them. First, the enactivist concept of cognition as action allows us to consider the first-person experience as a mode of action, and not as a state of the brain substrate. Second, the article deals with the “explanatory externalism” argument proposed by Noe, who refutes the image of cognition as a representation in the brain. Finally, in order to critically revise the concept of information as a unit of cognition, the author analyzes Cao’s idea, which represents a teleosemantic approach, but is in line with the general enactivist argumentation. Cao shows that the application of the concept “information” to neural processes is problematic: no naturalized information is found in the brain as a physical substrate. A critical revision of beliefs associated with the neural theory of consciousness leads us to recognize that there are not enough grounds for reducing consciousness to processes that take place in the brain. That is why Noe calls expectations that the visualization of processes taking place in the brain with the help of the modern equipment will be able to depict the experience of consciousness the “new phrenology”, thus indicating the naive character of neural reduction. The article concludes that natural science methods are insufficient for the study of consciousness.

scholarly journals Ceramide and Related-Sphingolipid Levels Are Not Altered in Disease-Associated Brain Regions of APPSLand APPSL/PS1M146LMouse Models of Alzheimer's Disease: Relationship with the Lack of Neurodegeneration?

2011 ◽  
Vol 2011 ◽  
pp. 1-10 ◽  
Author(s):  
Laurence Barrier ◽  
Bernard Fauconneau ◽  
Anastasia Noël ◽  
Sabrina Ingrand
Keyword(s):  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Animal Models ◽  
Neuronal Death ◽  
Time Course ◽  
Neuronal Loss ◽  
Brain Regions ◽  
App Processing ◽  
Ceramide Accumulation ◽  
The Brain

There is evidence linking sphingolipid abnormalities, APP processing, and neuronal death in Alzheimer's disease (AD). We previously reported a strong elevation of ceramide levels in the brain of the APPSL/PS1Ki mouse model of AD, preceding the neuronal death. To extend these findings, we analyzed ceramide and related-sphingolipid contents in brain from two other mouse models (i.e., APPSLand APPSL/PS1M146L) in which the time-course of pathology is closer to that seen in most currently available models. Conversely to our previous work, ceramides did not accumulate in disease-associated brain regions (cortex and hippocampus) from both models. However, the APPSL/PS1Ki model is unique for its drastic neuronal loss coinciding with strong accumulation of neurotoxic Aβisoforms, not observed in other animal models of AD. Since there are neither neuronal loss nor toxic Aβspecies accumulation in APPSLmice, we hypothesized that it might explain the lack of ceramide accumulation, at least in this model.

scholarly journals A Protective Role for Interleukin-1 Signaling during Mouse Adenovirus Type 1-Induced Encephalitis

2016 ◽  
Vol 91 (4) ◽  
Author(s):  
Luiza A. Castro-Jorge ◽  
Carla D. Pretto ◽  
Asa B. Smith ◽  
Oded Foreman ◽  
Kelly E. Carnahan ◽  
...  
Keyword(s):  
Inflammatory Cytokine ◽  
Time Course ◽  
Interleukin 1 ◽  
Adenovirus Type ◽  
Mouse Strains ◽  
Complex Nature ◽  
Type I ◽  
Viral Loads ◽  
The Brain

ABSTRACT Interleukin-1β (IL-1β), an inflammatory cytokine and IL-1 receptor ligand, has diverse activities in the brain. We examined whether IL-1 signaling contributes to the encephalitis observed in mouse adenovirus type 1 (MAV-1) infection, using mice lacking the IL-1 receptor (Il1r1 −/− mice). Il1r1 −/− mice demonstrated reduced survival, greater disruption of the blood-brain barrier (BBB), higher brain viral loads, and higher brain inflammatory cytokine and chemokine levels than control C57BL/6J mice. We also examined infections of mice defective in IL-1β production (Pycard −/− mice) and mice defective in trafficking of Toll-like receptors to the endosome (Unc93b1 −/− mice). Pycard −/− and Unc93b1 −/− mice showed lower survival (similar to Il1r1 −/− mice) than control mice but, unlike Il1r1 −/− mice, did not have increased brain viral loads or BBB disruption. Based on the brain cytokine levels, MAV-1-infected Unc93b1 −/− mice had a very different inflammatory profile from infected Il1r1 −/− and Pycard −/− mice. Histological examination demonstrated pathological findings consistent with encephalitis in control and knockout mice; however, intranuclear viral inclusions were seen only in Il1r1 −/− mice. A time course of infection of control and Il1r1 −/− mice evaluating the kinetics of viral replication and cytokine production revealed differences between the mouse strains primarily at 7 to 8 days after infection, when mice began succumbing to MAV-1 infection. In the absence of IL-1 signaling, we noted an increase in the transcription of type I interferon (IFN)-stimulated genes. Together, these results indicate that IL-1 signaling is important during MAV-1 infection and suggest that, in its absence, increased IFN-β signaling may result in increased neuroinflammation. IMPORTANCE The investigation of encephalitis pathogenesis produced by different viruses is needed to characterize virus and host-specific factors that contribute to disease. MAV-1 produces viral encephalitis in its natural host, providing a good model for studying factors involved in encephalitis development. We investigated the role of IL-1 signaling during MAV-1-induced encephalitis. Unexpectedly, the lack of IL-1 signaling increased the mortality and inflammation in mice infected with MAV-1. Also, there was an increase in the transcription of type I IFN-stimulated genes that correlated with the observed increased mortality and inflammation. The findings highlight the complex nature of encephalitis and suggests that IL-1 has a protective effect for the development of MAV-1-induced encephalitis.

Lateral ventricular ghrelin and fourth ventricular ghrelin induce similar increases in food intake and patterns of hypothalamic gene expression

2006 ◽  
Vol 290 (6) ◽  
pp. R1565-R1569 ◽  
Author(s):  
Kimberly P. Kinzig ◽  
Karen A. Scott ◽  
Jayson Hyun ◽  
Sheng Bi ◽  
Timothy H. Moran
Keyword(s):  
Gene Expression ◽  
Food Intake ◽  
Fourth Ventricle ◽  
Time Course ◽  
Arcuate Nucleus ◽  
Central Administration ◽  
Stimulatory Action ◽  
Hypothalamic Arcuate Nucleus ◽  
Ghrelin Receptors ◽  
The Brain

The gut peptide ghrelin has been shown to stimulate food intake after both peripheral and central administration, and the hypothalamic arcuate nucleus has been proposed to be the major site for mediating this feeding stimulatory action. Ghrelin receptors are widely distributed in the brain, and hindbrain ghrelin administration has been shown to potently stimulate feeding, suggesting that there may be other sites for ghrelin action. In the present study, we have further assessed potential sites for ghrelin action by comparing the ability of lateral and fourth ventricular ghrelin administration to stimulate food intake and alter patterns of hypothalamic gene expression. Ghrelin (0.32, 1, or 3.2 nmol) in the lateral or fourth ventricle significantly increased food intake in the first 4 h after injection, with no ventricle-dependent differences in degree or time course of hyperphagia. One nanomole of ghrelin into either the lateral or fourth ventricle resulted in similar increases in arcuate nucleus neuropeptide Y mRNA expression. Expression levels of agouti-related peptide or proopiomelanocortin mRNA were not affected by ghrelin administration. These data demonstrate that ghrelin can affect food intake and hypothalamic gene expression through interactions at multiple brain sites.

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