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.

scholarly journals Pain Detection and the Privacy of Subjective Experience

2007 ◽  
Vol 33 (2-3) ◽  
pp. 433-456 ◽  
Author(s):  
Adam J. Kolber
Keyword(s):  
Subjective Experience ◽  
Brain Regions ◽  
Physical Pain ◽  
Medical Evidence ◽  
Functional Magnetic Resonance ◽  
Positron Emission ◽  
Pain Symptoms ◽  
The Brain ◽  
Insight Into ◽  
Neuroimaging Techniques

A neurologist with abdominal pain goes to see a gastroenterologist for treatment. The gastroenterologist asks the neurologist where it hurts. The neurologist replies, “In my head, of course.” Indeed, while we can feel pain throughout much of our bodies, pain signals undergo most of their processing in the brain. Using neuroimaging techniques like functional magnetic resonance imaging (“fMRI”) and positron emission tomography (“PET”), researchers have more precisely identified brain regions that enable us to experience physical pain. Certain regions of the brain's cortex, for example, increase in activation when subjects are exposed to painful stimuli. Furthermore, the amount of activation increases with the intensity of the painful stimulus. These findings suggest that we may be able to gain insight into the amount of pain a particular person is experiencing by non-invasively imaging his brain.Such insight could be particularly valuable in the courtroom where we often have no definitive medical evidence to prove or disprove claims about the existence and extent of pain symptoms.

scholarly journals Intermittent brain network reconfigurations and the resistance to social media influence

2021 ◽  
Author(s):  
Italo Ivo Lima Dias Pinto ◽  
Nuttida Rungratsameetaweemana ◽  
Kristen Flaherty ◽  
Aditi Periyannan ◽  
Amir Meghdadi ◽  
...  
Keyword(s):  
Social Media ◽  
Brain Networks ◽  
Brain Network ◽  
Opinion Formation ◽  
Opinion Change ◽  
Neural Processes ◽  
Social Media Platforms ◽  
Media Platform ◽  
The Brain ◽  
Source Of Information

Since their development, social media has grown as a source of information and has a significant impact on opinion formation. Individuals interact with others and content via social media platforms in a variety of ways but it remains unclear how decision making and associated neural processes are impacted by the online sharing of informational content, from factual to fabricated. Here, we use EEG to estimate dynamic reconfigurations of brain networks and probe the neural changes underlying opinion change (or formation) within individuals interacting with a simulated social media platform. Our findings indicate that the individuals who show more malleable opinions are characterized by less frequent network reconfigurations while those with more rigid opinions tend to have more flexible brain networks with frequent reconfigurations. The nature of these frequent network configurations suggests a fundamentally different thought process between the individuals who are more easily influenced by social media and those who are not. We also show that these reconfigurations are distinct to the brain dynamics during an in-person discussion with strangers on the same content. Together, these findings suggest that network reconfigurations in the brain may not only be diagnostic to the informational context but also the underlie opinion formation.

scholarly journals COMP-03. TUMOR CONNECTOME: INSIGHT INTO THE IMPACT OF CNS NEOPLASIA AND THERAPY ON THE BRAIN NETWORK

2018 ◽  
Vol 20 (suppl_6) ◽  
pp. vi64-vi64
Author(s):  
Drew Parker ◽  
Jacob Alappatt ◽  
Mark Elliott ◽  
Steven Brem ◽  
Ragini Verma
Keyword(s):  
Brain Network ◽  
The Impact ◽  
The Brain ◽  
Insight Into

Psychiatry between Psyche and Brain

2021 ◽  
pp. 181-195
Author(s):  
Thomas Fuchs
Keyword(s):  
Mental Disorders ◽  
Social Relations ◽  
Subjective Experience ◽  
Mental Illnesses ◽  
The Other ◽  
Brain Diseases ◽  
Neural Processes ◽  
Neural Substrate ◽  
The One ◽  
The Brain

Since its development around 1800, psychiatry has been moving between the poles of the sciences and the humanities, being directed toward subjective experience on the one hand and toward the neural substrate on the other hand. Today, this dualism seems to be overcome by a naturalism which identifies subjective experience with neural processes—according to the slogan “mental disorders are brain diseases.” Psychiatry thus tends to isolate mental illnesses from the patients’ social relationships and to neglect subjectivity and intersubjectivity in their explanation. What should be searched for instead is a paradigm that can establish psychiatry as a relational medicine in an encompassing sense: as a science and practice of biological, psychological and social relations, and their disorders. Within such a paradigm, the brain may be grasped and researched as the central “relational organ” without reductionist implications.

Impulsivity and neural correlates of response inhibition in schizophrenia

2010 ◽  
Vol 41 (2) ◽  
pp. 291-299 ◽  
Author(s):  
A. Kaladjian ◽  
R. Jeanningros ◽  
J.-M. Azorin ◽  
J.-L. Anton ◽  
P. Mazzola-Pomietto
Keyword(s):  
Response Inhibition ◽  
Healthy Subjects ◽  
Neural Correlates ◽  
Brain Network ◽  
Cerebral Activation ◽  
Neural Processes ◽  
Psychometric Measures ◽  
The Right ◽  
The Relationship ◽  
The Brain

BackgroundThe clinical picture of schizophrenia is frequently worsened by manifestations of impulsivity. However, the neural correlates of impulsivity in this disorder are poorly known. Although impulsivity has been related to disturbances of the neural processes underlying response inhibition, no studies have yet examined the relationship between these processes and psychometric measures of impulsivity in schizophrenia. This was the aim of the current investigation.MethodEvent-related functional magnetic resonance imaging in conjunction with a Go/NoGo task was employed to probe the neural activity associated with response inhibition in 26 patients with schizophrenia and 30 healthy comparison subjects. All participants also completed the Barratt Impulsiveness Scale – version 11 (BIS-11). Voxel-wise regression analyses were used to examine the relationship between the BIS-11 score and brain activation during response inhibition in each group.ResultsPatients with schizophrenia were more impulsive than healthy subjects, as indicated by higher BIS-11 scores. Patients, but not healthy subjects, were found to display a positive correlation between these scores and cerebral activation associated with response inhibition. This correlation involves a unique cluster localized within the right ventrolateral prefrontal cortex (VLPFC), a key node of the brain network subserving response inhibition.ConclusionsWe evidenced in patients with schizophrenia that greater BIS-11 scores are associated with greater activation within the right VLPFC during response inhibition. This finding suggests that the efficiency of this brain region to process inhibitory control is reduced in the more impulsive patients.

scholarly journals Bidirectionally connected cores in a mouse connectome: Towards extracting the brain subnetworks essential for consciousness

2021 ◽  
Author(s):  
Jun Kitazono ◽  
Yuma Aoki ◽  
Masafumi Oizumi
Keyword(s):  
Conscious Experience ◽  
Brain Network ◽  
Network Structures ◽  
Whole Brain ◽  
Feedback Processing ◽  
Feed Forward ◽  
The Brain ◽  
Insight Into

Where in the brain consciousness resides remains unclear. It has been suggested that the subnetworks supporting consciousness should be bidirectionally (recurrently) connected because both feed-forward and feedback processing are necessary for conscious experience. Accordingly, evaluating which subnetworks are bidirectionally connected and the strength of these connections would likely aid the identification of regions essential to consciousness. Here, we propose a method for hierarchically decomposing a network into cores with different strengths of bidirectional connection, as a means of revealing the structure of the complex brain network. We applied the method to a whole-brain mouse connectome. We found that cores with strong bidirectional connections consisted of regions presumably essential to consciousness (e.g., the isocortical and thalamic regions, and claustrum) and did not include regions presumably irrelevant to consciousness (e.g., cerebellum). Contrarily, we could not find such correspondence between cores and consciousness when we applied other simple methods which ignored bidirectionality. These findings suggest that our method provides a novel insight into the relation between bidirectional brain network structures and consciousness.

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.

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.

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