A Preliminary Account of the Clinical Effects of Polarizing the Brain in Certain Psychiatric Disorders

1964 ◽  
Vol 110 (469) ◽  
pp. 773-785 ◽  
Author(s):  
J. W. T. Redfearn ◽  
O. C. J. Lippold ◽  
R. Costain
Keyword(s):  
Psychiatric Disorders ◽  
Human Subjects ◽  
Cellular Level ◽  
Psychological Effects ◽  
Clinical Effects ◽  
Preliminary Account ◽  
After Effect ◽  
The Brain ◽  
Cortical Polarization ◽  
Effect Of Surface

A previous paper (Lippold and Redfearn, 1964) described the mental changes that can be produced by the passage of small polarizing currents through the brain in human subjects. It became apparent during the course of these experiments that some of the effects persisted for hours or days after the current had been turned off. A persistent excitatory after-effect of surface-positive cortical polarization has recently been demonstrated in the rat (Bindman, Lippold and Redfearn, 1962). It is possible that a similar phenomenon, at the cellular level, is responsible for the long-lasting psychological effects of polarization.

scholarly journals Serotonin suppresses slow oscillations by activating somatostatin interneurons via the 5-HT2A receptor

2020 ◽  
Author(s):  
Roberto De Filippo ◽  
Benjamin R. Rost ◽  
Alexander Stumpf ◽  
Claire Cooper ◽  
John J. Tukker ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Slow Wave Sleep ◽  
Cortical Network ◽  
Psychological Effects ◽  
Network Activity ◽  
Slow Oscillations ◽  
Physiological Processes ◽  
Electrophysiological Recordings ◽  
Serotonergic Drugs ◽  
The Brain

AbstractSerotonin (5-HT) affects multiple physiological processes in the brain and is involved in a number of psychiatric disorders. 5-HT axons reach all cortical areas; however, the precise mechanism by which 5-HT modulates cortical network activity is not yet fully understood. We investigated the effects of 5-HT on slow oscillations (SO), a synchronized cortical network activity universally present across species. SO are observed during slow-wave sleep and anesthesia and are considered the default cortical activity pattern. Combining opto- and pharmacogenetic manipulations with electrophysiological recordings, we discovered that 5-HT inhibits SO within the entorhinal cortex (EC) by activating somatostatin-expressing (Som) interneurons via the 5-HT2A receptor (5-HT2AR). This receptor is involved in the etiology of different psychiatric disorders and mediates the psychological effects of many psychoactive serotonergic drugs, suggesting that 5-HT targeting of Som interneurons may play an important role in these processes.

scholarly journals Clinical Evaluation of Cingulum Bundle Connectivity for Neurosurgical Hypothesis Development

Neurosurgery ◽  
2019 ◽  
Vol 86 (5) ◽  
pp. 724-735
Author(s):  
Jennifer A Sweet ◽  
Sinem Balta Beylergil ◽  
Suraj Thyagaraj ◽  
Eric Z Herring ◽  
Jesse E Drapekin ◽  
...  
Keyword(s):  
Psychiatric Disorders ◽  
Human Subjects ◽  
Brain Structures ◽  
Brain Regions ◽  
Neurosurgical Procedures ◽  
Tract Tracing ◽  
Healthy Human ◽  
Cingulum Bundle ◽  
The Brain

Abstract BACKGROUND The cingulum bundle (CB) has long been a target for psychiatric neurosurgical procedures, but with limited understanding of the brain networks being impacted. Recent advances in human tractography could provide a foundation to better understand the effects of neurosurgical interventions on the CB; however, the reliability of tractography remains in question. OBJECTIVE To evaluate the ability of different tractography techniques, derived from typical, human diffusion-weighted imaging (DWI) data, to characterize CB connectivity described in animal models. This will help validate the clinical applicability of tractography, and generate insight on current and future neurosurgical targets for psychiatric disorders. METHODS Connectivity of the CB in 15 healthy human subjects was evaluated using DWI-based tractography, and compared to tract-tracing findings from nonhuman primates. Brain regions of interest were defined to coincide with the animal model. Tractography was performed using 3 techniques (FSL probabilistic, Camino probabilistic, and Camino deterministic). Differences in connectivity were assessed, and the CB segment with the greatest connectivity was determined. RESULTS Each tractography technique successfully reproduced the animal tracing model with a mean accuracy of 72% (68-75%, P < .05). Additionally, one region of the CB, the rostral dorsal segment, had significantly greater connectivity to associated brain structures than all other CB segments (P < .05). CONCLUSION Noninvasive, in vivo human analysis of the CB, using clinically available DWI for tractography, consistently reproduced the results of an animal tract-tracing model. This suggests that tractography of the CB can be used for clinical applications, which may aid in neurosurgical targeting for psychiatric disorders.

scholarly journals Effects of non-invasive brain stimulation in children and young people with psychiatric disorders: a protocol for a systematic review

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Yael D. Lewis ◽  
Lucy Gallop ◽  
Iain C. Campbell ◽  
Ulrike Schmidt
Keyword(s):  
Systematic Review ◽  
Young People ◽  
Psychiatric Disorders ◽  
Brain Stimulation ◽  
Grey Literature ◽  
Significant Proportion ◽  
Clinical Effects ◽  
Children And Young People ◽  
Non Invasive ◽  
Specific Symptoms

Abstract Background Most psychiatric disorders have their onset in childhood or adolescence, and if not fully treated have the potential for causing life-long psycho-social and physical sequelae. Effective psychotherapeutic and medication treatments exist, but a significant proportion of children and young people do not make a full recovery. Thus, novel, safe, brain-based alternatives or adjuncts to conventional treatments are needed. Repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS) are non-invasive brain stimulation (NIBS) techniques which have shown clinical benefits in adult psychiatric conditions. However, in children and young people their efficacy is not well established. The objective of this study will be to systematically evaluate the evidence on clinical effects of NIBS in children and young people with psychiatric disorders, assessing disorder-specific symptoms, mood and neurocognitive functions. Methods We designed and registered a study protocol for a systematic review. We will include randomised and non-randomised controlled trials and observational studies (e.g. cohort, case-control, case series) assessing the effects of NIBS in children and young people (aged ≤ 24 years old) for psychiatric disorders. The primary outcome will be reduction of disorder-specific symptoms. Secondary outcomes will include effects on mood and cognition. A comprehensive search from database inception onwards will be conducted in MEDLINE, EMBASE and PsycINFO. Grey literature will be identified through searching multiple clinical trial registries. Two reviewers will independently screen all citations, full-text articles and abstract data. The methodological quality of the studies will be appraised using appropriate tools. We will provide a narrative synthesis of the evidence and according to heterogeneity will conduct an appropriate meta-analysis. Additional analyses will be conducted to explore the potential sources of heterogeneity. Discussion This systematic review will provide a broad and comprehensive evaluation of the evidence on clinical effects of NIBS in children and young people with psychiatric disorders. Our findings will be reported according to the PRISMA guidelines and will be of interest to multiple audiences (including patients, researchers, healthcare professionals and policy-makers). Results will be published in a peer-reviewed journal. Systematic review registration PROSPERO CRD42019158957

Event-Related Potentials in Psychiatry: Approaches to Research and Clinical Applications

1983 ◽  
Vol 17 (4) ◽  
pp. 307-318 ◽  
Author(s):  
H. G. Stampfer
Keyword(s):  
Information Processing ◽  
Psychiatric Disorders ◽  
Rapid Development ◽  
Event Related Potentials ◽  
Clinical Applications ◽  
Direct Access ◽  
Practical Application ◽  
Clinical Methods ◽  
Related Potentials ◽  
The Brain

This article suggests that the potential usefulness of event-related potentials in psychiatry has not been fully explored because of the limitations of various approaches to research adopted to date, and because the field is still undergoing rapid development. Newer approaches to data acquisition and methods of analysis, combined with closer co-operation between medical and physical scientists, will help to establish the practical application of these signals in psychiatric disorders and assist our understanding of psychophysiological information processing in the brain. Finally, it is suggested that psychiatrists should seek to understand these techniques and the data they generate, since they provide more direct access to measures of complex cerebral processes than current clinical methods.

A preliminary account of brain growth in postlarval Nereis virens (Polychaeta: Annelida): a [3H]thymidine study

1980 ◽  
Vol 58 (11) ◽  
pp. 2141-2149
Author(s):  
Jane Easdown ◽  
Joan Marsden ◽  
Khazal Paradis ◽  
Kathryn Bell ◽  
Judith Jost
Keyword(s):  
Cell Division ◽  
Brain Growth ◽  
Nereis Virens ◽  
Preliminary Account ◽  
Reduced Rate ◽  
The Brain

Labelling of the supraoesophageal ganglion of postlarval Nereis virens with [3H]thymidine indicates that cell division is most active in very small worms, less than 0.1 g in weight. In such animals a few, small, labelled neurons were found, but only after 13 h of exposure to isotope. After shorter exposures, very small, undifferentiated labelled cells were seen in most of the ganglionic areas of the brain, although the various ganglionic nuclei differ in the time of first appearance of their characteristic neurons. In older animals gliagenesis continues at a reduced rate and neuron production becomes extremely slow.

scholarly journals Multifaceted origins of sex differences in the brain

2016 ◽  
Vol 371 (1688) ◽  
pp. 20150106 ◽  
Author(s):  
Margaret M. McCarthy
Keyword(s):  
Sex Differences ◽  
State Of The Art ◽  
Human Subjects ◽  
Special Issue ◽  
Molecular Analyses ◽  
The Past ◽  
Current State ◽  
Biological Variable ◽  
Males And Females ◽  
The Brain

Studies of sex differences in the brain range from reductionistic cell and molecular analyses in animal models to functional imaging in awake human subjects, with many other levels in between. Interpretations and conclusions about the importance of particular differences often vary with differing levels of analyses and can lead to discord and dissent. In the past two decades, the range of neurobiological, psychological and psychiatric endpoints found to differ between males and females has expanded beyond reproduction into every aspect of the healthy and diseased brain, and thereby demands our attention. A greater understanding of all aspects of neural functioning will only be achieved by incorporating sex as a biological variable. The goal of this review is to highlight the current state of the art of the discipline of sex differences research with an emphasis on the brain and to contextualize the articles appearing in the accompanying special issue.

Variables That Influence the Generation of Random Sequences: An Update

1997 ◽  
Vol 84 (2) ◽  
pp. 627-661 ◽  
Author(s):  
Peter Brugger
Keyword(s):  
Short Term Memory ◽  
Human Subjects ◽  
Complete Suppression ◽  
Random Generation ◽  
Short Term ◽  
Random Sequences ◽  
Potential Applications ◽  
Basic Experiments ◽  
The Brain ◽  
Relevant Work

This article updates Tune's 1964 review of variables influencing human subjects' attempts at generating random sequences of alternatives. It also covers aspects not included in the original review such as randomization behavior by patients with neurological and psychiatric disorders. Relevant work from animal research (spontaneous alternation paradigm) is considered as well. It is conjectured that Tune's explanation of sequential nonrandomness in terms of a limited capacity of short-term memory can no longer be maintained. Rather, interdependence among consecutive choices is considered a consequence of an organism's natural susceptibility to interference. Random generation is thus a complex action which demands complete suppression of any rule-governed behavior. It possibly relies on functions of the frontal lobes but cannot otherwise be “localized” to restricted regions of the brain. Possible developments in the field are briefly discussed, both with respect to basic experiments regarding the nature of behavioral nonrandomness and to potential applications of random-generation tasks.

scholarly journals Modeling Neuroimmune Interactions in Human Subjects and Animal Models to Predict Subtype-Specific Multidrug Treatments for Gulf War Illness

2021 ◽  
Vol 22 (16) ◽  
pp. 8546
Author(s):  
Francisco J. Carrera Arias ◽  
Kristina Aenlle ◽  
Maria Abreu ◽  
Mary A. Holschbach ◽  
Lindsay T. Michalovicz ◽  
...  
Keyword(s):  
Signaling Pathways ◽  
Human Subjects ◽  
Treatment Strategies ◽  
Gulf War ◽  
Clinical Samples ◽  
Stable States ◽  
Response Dynamics ◽  
Gulf War Illness ◽  
Bbb Permeability ◽  
The Brain

Gulf War Illness (GWI) is a persistent chronic neuroinflammatory illness exacerbated by external stressors and characterized by fatigue, musculoskeletal pain, cognitive, and neurological problems linked to underlying immunological dysfunction for which there is no known treatment. As the immune system and the brain communicate through several signaling pathways, including the hypothalamic–pituitary–adrenal (HPA) axis, it underlies many of the behavioral and physiological responses to stressors via blood-borne mediators, such as cytokines, chemokines, and hormones. Signaling by these molecules is mediated by the semipermeable blood–brain barrier (BBB) made up of a monocellular layer forming an integral part of the neuroimmune axis. BBB permeability can be altered and even diminished by both external factors (e.g., chemical agents) and internal conditions (e.g., acute or chronic stress, or cross-signaling from the hypothalamic–pituitary–gonadal (HPG) axis). Such a complex network of regulatory interactions that possess feed-forward and feedback connections can have multiple response dynamics that may include several stable homeostatic states beyond normal health. Here we compare immune and hormone measures in the blood of human clinical samples and mouse models of Gulf War Illness (GWI) subtyped by exposure to traumatic stress for subtyping this complex illness. We do this via constructing a detailed logic model of HPA–HPG–Immune regulatory behavior that also considers signaling pathways across the BBB to neuronal–glial interactions within the brain. We apply conditional interactions to model the effects of changes in BBB permeability. Several stable states are identified in the system beyond typical health. Following alignment of the human and mouse blood profiles in the context of the model, mouse brain sample measures were used to infer the neuroinflammatory state in human GWI and perform treatment simulations using a genetic algorithm to optimize the Monte Carlo simulations of the putative treatment strategies aimed at returning the ill system back to health. We identify several ideal multi-intervention strategies and potential drug candidates that may be used to treat chronic neuroinflammation in GWI.

scholarly journals Learning to synchronize: Midfrontal theta dynamics during rule switching

2020 ◽  
Author(s):  
Pieter Verbeke ◽  
Kate Ergo ◽  
Esther De Loof ◽  
Tom Verguts
Keyword(s):  
Negative Feedback ◽  
Human Subjects ◽  
Learning Task ◽  
Theta Oscillations ◽  
Prediction Errors ◽  
Hierarchical Learning ◽  
Theta Power ◽  
Negative Prediction ◽  
Theta Phase ◽  
The Brain

AbstractIn recent years, several hierarchical extensions of well-known learning algorithms have been proposed. For example, when stimulus-action mappings vary across time or context, the brain may learn two or more stimulus-action mappings in separate modules, and additionally (at a hierarchically higher level) learn to appropriately switch between those modules. However, how the brain mechanistically coordinates neural communication to implement such hierarchical learning, remains unknown. Therefore, the current study tests a recent computational model that proposed how midfrontal theta oscillations implement such hierarchical learning via the principle of binding by synchrony (Sync model). More specifically, the Sync model employs bursts at theta frequency to flexibly bind appropriate task modules by synchrony. 64-channel EEG signal was recorded while 27 human subjects (Female: 21, Male: 6) performed a probabilistic reversal learning task. In line with the Sync model, post-feedback theta power showed a linear relationship with negative prediction errors, but not with positive prediction errors. This relationship was especially pronounced for subjects with better behavioral fit (measured via AIC) of the Sync model. Also consistent with Sync model simulations, theta phase-coupling between midfrontal electrodes and temporo-parietal electrodes was stronger after negative feedback. Our data suggest that the brain uses theta power and synchronization for flexibly switching between task rule modules, as is useful for example when multiple stimulus-action mappings must be retained and used.Significance StatementEveryday life requires flexibility in switching between several rules. A key question in understanding this ability is how the brain mechanistically coordinates such switches. The current study tests a recent computational framework (Sync model) that proposed how midfrontal theta oscillations coordinate activity in hierarchically lower task-related areas. In line with predictions of this Sync model, midfrontal theta power was stronger when rule switches were most likely (strong negative prediction error), especially in subjects who obtained a better model fit. Additionally, also theta phase connectivity between midfrontal and task-related areas was increased after negative feedback. Thus, the data provided support for the hypothesis that the brain uses theta power and synchronization for flexibly switching between rules.

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