scholarly journals How non-veridical perception drives actions in healthy humans - Evidence from Synaesthesia

2018 ◽  
Author(s):  
Marie Luise Schreiter ◽  
Witold X. Chmielewski ◽  
Jamie Ward ◽  
Christian Beste
Keyword(s):  
Motor Control ◽  
Real World ◽  
Underlying Mechanism ◽  
Veridical Perception ◽  
Healthy Human ◽  
Healthy Humans ◽  
Model Condition ◽  
Clinical Conditions ◽  
Influence Behavior ◽  
Perception Action

AbstractWe continually perform actions driven by our perception and it is commonly held that only objectively perceived changes within the ‘real’ world affect behaviour. Exceptions are usually only made for clinical conditions associated with hallucinations, where objectively non-existent percepts can influence behavior. Using synaesthesia as a model condition, we show that even in healthy populations irrelevant non-veridical precepts exert an effect on action. By non-veridical we refer to stimulus dimensions that are only subjectively perceived to be there. Applying electrophysiological (EEG) methods, we show that although these examined peculiarities are perceptual in nature, not primarily perceptual processes underlie the effects of irrelevant non-veridical perceptions on actions. Rather, high-order processes linking perceptions and motor control in medial frontal cortices reflect the underlying mechanism how irrelevant non-veridical perceptions modulate behaviour. Our results challenge assumptions about the determinants of healthy human behaviour but can be embedded within existing frameworks detailing perception action interactions.

scholarly journals How non-veridical perception drives actions in healthy humans: evidence from synaesthesia

2019 ◽  
Vol 374 (1787) ◽  
pp. 20180574 ◽  
Author(s):  
Marie Luise Schreiter ◽  
Witold X. Chmielewski ◽  
Jamie Ward ◽  
Christian Beste
Keyword(s):  
Executive Control ◽  
Perception And Action ◽  
Early Stage ◽  
Event Related Potential ◽  
Veridical Perception ◽  
Theoretical Frameworks ◽  
Healthy Humans ◽  
Model Condition ◽  
Localization Analysis ◽  
Health Disorders

We continually perform actions that are driven by our perception and it is a commonly held view that only objectively perceived changes within the ‘real’ world affect behaviour. Exceptions are generally only made for mental health disorders associated with delusions and hallucinations where behaviour may be triggered by the experience of objectively non-existent percepts. Here, we demonstrate, using synaesthesia as a model condition (in N = 19 grapheme-colour synaesthetes), how objectively non-existent (i.e. non-veridical) but still non-pathological perceptions affect actions in healthy humans. Using electroencephalography, we determine whether early-stage perceptual processes (reflected by P1 and N1 event-related potential (ERP) components), or late-stage-integration processes (reflected by N2 component), underlie the effects of non-veridical perceptions on action control. ERP analysis suggests that even though the examined peculiarities and experimental variations are perceptual in nature, it is not early-stage perceptual processes, but rather higher-order executive control processes linking perceptions to the appropriate motor response underlying this effect. Source localization analysis implicates activation within medial frontal cortices in the effect of how irrelevant non-veridical perceptions modulate behaviour. Our results challenge common conceptions about the determinants of human behaviour but can be explained by well-established theoretical frameworks detailing the link between perception and action. This article is part of a discussion meeting issue ‘Bridging senses: novel insights from synaesthesia’.

scholarly journals Associative learning and extinction of conditioned threat predictors across sensory modalities

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Laura. R. Koenen ◽  
Robert. J. Pawlik ◽  
Adriane Icenhour ◽  
Ljubov Petrakova ◽  
Katarina Forkmann ◽  
...  
Keyword(s):  
Visceral Pain ◽  
Neural Correlates ◽  
Imaging Studies ◽  
Somatic Pain ◽  
Healthy Humans ◽  
Sensory Modalities ◽  
The Face ◽  
Nocebo Effects ◽  
Conditioned Responses ◽  
Clinical Conditions

AbstractThe formation and persistence of negative pain-related expectations by classical conditioning remain incompletely understood. We elucidated behavioural and neural correlates involved in the acquisition and extinction of negative expectations towards different threats across sensory modalities. In two complementary functional magnetic resonance imaging studies in healthy humans, differential conditioning paradigms combined interoceptive visceral pain with somatic pain (study 1) and aversive tone (study 2) as exteroceptive threats. Conditioned responses to interoceptive threat predictors were enhanced in both studies, consistently involving the insula and cingulate cortex. Interoceptive threats had a greater impact on extinction efficacy, resulting in disruption of ongoing extinction (study 1), and selective resurgence of interoceptive CS-US associations after complete extinction (study 2). In the face of multiple threats, we preferentially learn, store, and remember interoceptive danger signals. As key mediators of nocebo effects, conditioned responses may be particularly relevant to clinical conditions involving disturbed interoception and chronic visceral pain.

Absence of systematic relationships between REMS duration episodes and spectral power Delta and Ultra-Slow bands in contiguous NREMS episodes in healthy humans

2013 ◽  
Vol 110 (1) ◽  
pp. 162-169 ◽  
Author(s):  
O. Le Bon ◽  
P. Linkowski
Keyword(s):  
Spectral Power ◽  
Sleep Cycle ◽  
Consecutive Series ◽  
Sleep Regulation ◽  
Healthy Human ◽  
Sleep Quantity ◽  
Healthy Humans ◽  
Crucial Component ◽  
Sleep Physiology ◽  
Human Participants

Previous studies in animals and humans have reported correlations between the durations of rapid eye movement sleep (REMS) episodes and immediately preceding or subsequent non-REMS (NREMS) episodes. The relationship between these two types of sleep is a crucial component in understanding the regulation and neurophysiology of ultradian alternations that occur during sleep. Although the present study replicated previous studies, we also measured NREMS in terms of spectral power Delta and Ultra-Slow bands in addition to duration in examining correlations. The spectral power Delta band, also known as slow-wave activity, measures sleep quantity and is believed to reflect sleep physiology better than mere episode durations. The Ultra-Slow spectral power band was analyzed in parallel. Healthy human participants of both sexes ( n = 26, age range 15–45 yr, n = 12 female) were carefully selected to participate in two consecutive series of home polysomnograms performed after 2 nights of habituation to the equipment. In the analyses, REMS episode durations (minutes) were compared with immediately preceding and immediately subsequent NREMS episodes (Delta and Ultra-Slow power) in each sleep cycle. REMS episode duration was more strongly correlated with preceding NREMS episodes than with subsequent NREMS episodes. However, in most cases, no correlations were observed in either direction. One ultradian sleep regulation hypothesis, which is based on stronger correlations between REMS and subsequent NREMS episode durations, holds that the main purpose of REMS is to reactivate NREMS during each sleep cycle. The present results do not support that hypothesis.

scholarly journals Genotypic and Phenotypic Traits That Distinguish Neonatal Meningitis-Associated Escherichia coli from Fecal E. coli Isolates of Healthy Human Hosts

2012 ◽  
Vol 78 (16) ◽  
pp. 5824-5830 ◽  
Author(s):  
Catherine M. Logue ◽  
Curt Doetkott ◽  
Paul Mangiamele ◽  
Yvonne M. Wannemuehler ◽  
Timothy J. Johnson ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Phylogenetic Group ◽  
Neonatal Meningitis ◽  
Phenotypic Traits ◽  
Healthy Human ◽  
Content Type ◽  
Plasmid Content ◽  
E Coli ◽  
Healthy Humans ◽  
Definition Of

ABSTRACTNeonatal meningitisEscherichia coli(NMEC) is one of the top causes of neonatal meningitis worldwide. Here, 85 NMEC and 204 fecalE. coliisolates from healthy humans (HFEC) were compared for possession of traits related to virulence, antimicrobial resistance, and plasmid content. This comparison was done to identify traits that typify NMEC and distinguish it from commensal strains to refine the definition of the NMEC subpathotype, identify traits that might contribute to NMEC pathogenesis, and facilitate choices of NMEC strains for future study. A large number ofE. colistrains from both groups were untypeable, with the most common serogroups occurring among NMEC being O18, followed by O83, O7, O12, and O1. NMEC strains were more likely than HFEC strains to be assigned to the B2 phylogenetic group. Few NMEC or HFEC strains were resistant to antimicrobials. Genes that best discriminated between NMEC and HFEC strains and that were present in more than 50% of NMEC isolates were mainly from extraintestinal pathogenicE. coligenomic and plasmid pathogenicity islands. Several of these defining traits had not previously been associated with NMEC pathogenesis, are of unknown function, and are plasmid located. Several genes that had been previously associated with NMEC virulence did not dominate among the NMEC isolates. These data suggest that there is much about NMEC virulence that is unknown and that there are pitfalls to studying single NMEC isolates to represent the entire subpathotype.

Differential energetic response of brain vs. skeletal muscle upon glycemic variations in healthy humans

2008 ◽  
Vol 294 (1) ◽  
pp. R12-R16 ◽  
Author(s):  
Kerstin M. Oltmanns ◽  
Uwe H. Melchert ◽  
Harald G. Scholand-Engler ◽  
Maria C. Howitz ◽  
Bernd Schultes ◽  
...  
Keyword(s):  
Skeletal Muscle ◽  
Underlying Mechanism ◽  
High Energy ◽  
Resonance Spectroscopy ◽  
Energy Status ◽  
High Energy Phosphate ◽  
Available Energy ◽  
Healthy Humans ◽  
High Energy Phosphate Metabolism ◽  
The Brain

The brain regulates all metabolic processes within the organism, and therefore, its energy supply is preserved even during fasting. However, the underlying mechanism is unknown. Here, it is shown, using 31P-magnetic resonance spectroscopy that during short periods of hypoglycemia and hyperglycemia, the brain can rapidly increase its high-energy phosphate content, whereas there is no change in skeletal muscle. We investigated the key metabolites of high-energy phosphate metabolism as rapidly available energy stores by 31P MRS in brain and skeletal muscle of 17 healthy men. Measurements were performed at baseline and during dextrose or insulin-induced hyperglycemia and hypoglycemia. During hyperglycemia, phosphocreatine (PCr) concentrations increased significantly in the brain ( P = 0.013), while there was a similar trend in the hypopglycemic condition ( P = 0.055). Skeletal muscle content remained constant in both conditions ( P > 0.1). ANOVA analyses comparing changes from baseline to the respective glycemic plateau in brain (up to +15%) vs. muscle (up to −4%) revealed clear divergent effects in both conditions ( P < 0.05). These effects were reflected by PCr/Pi ratio ( P < 0.05). Total ATP concentrations revealed the observed divergency only during hyperglycemia ( P = 0.018). These data suggest that the brain, in contrast to peripheral organs, can activate some specific mechanisms to modulate its energy status during variations in glucose supply. A disturbance of these mechanisms may have far-reaching implications for metabolic dysregulation associated with obesity or diabetes mellitus.

scholarly journals Capsule Formulation of Ethanolic Extract of Pasak Bumi (Eurycoma Longifolia Jack.,) and its Effect on Human Health Vital Signs

2017 ◽  
Vol 22 (2) ◽  
pp. 91
Author(s):  
Laela Hayu Nurani ◽  
Eka Kumalasari ◽  
Abdul Rohman ◽  
Sitarina Widyarini
Keyword(s):  
Bitter Taste ◽  
Vital Signs ◽  
Ethanolic Extract ◽  
Ethanol Extract ◽  
Inclusion Criteria ◽  
Capsule Formulation ◽  
Healthy Human ◽  
Eurycoma Longifolia ◽  
Healthy Humans ◽  
Eurycoma Longifolia Jack

Pasak bumi (Eurycoma longifolia) has the potential to be developed as antihypertensive, antipyretic, aphrodisiacs and health supplements. The use of E. longifolia as a traditional medicine needs to be pursued in the form of more effective and appropriate formulation. The capsule preparations are easy to make and cancover the bitter taste of E. longifolia. Clinical trials in this study use design pre-post treatment in healthy humans. Subjects used were male - healthy men and healthy women who met inclusion criteria and were subjected with formulated capsule for 14 days. The study resulted capsule formula comprising of the ethanolic extract of E. longifolia 300 mg, vivapur 101 300 mg, 58 mg maydis starch, aerosil 3%, talc 2%, and Mg stearate 1%. The results showed that the capsule of E. longifolia did not affect the value of heart rate, respiration rate, body temperature and weight (P > 0.05), based on paired t-test, but they causes a decrease in blood pressure of healthy human. The ethanol extract of E. longifolia caused vasodilation of blood vessels that can be used in antihypertensive therapy.

Selective effects of serotonergic psychoactive agents on gastrointestinal functions in health

2003 ◽  
Vol 284 (1) ◽  
pp. G130-G137 ◽  
Author(s):  
Heather J. Chial ◽  
Michael Camilleri ◽  
Duane Burton ◽  
George Thomforde ◽  
Kevin W. Olden ◽  
...  
Keyword(s):  
Reuptake Inhibitor ◽  
Human Subjects ◽  
Functional Gastrointestinal Disorders ◽  
Gastric Volume ◽  
Colonic Transit ◽  
Selective Serotonin ◽  
Healthy Human ◽  
Double Blind ◽  
Solid Meal ◽  
Healthy Humans

This study evaluated the effects of serotonergic psychoactive agents on gastrointestinal functions in healthy human subjects. Participants received one of four regimens in a randomized, double-blind manner: buspirone, a 5-HT1Areceptor agonist (10 mg twice daily); paroxetine, a selective serotonin reuptake inhibitor (20 mg daily); venlafaxine-XR, a selective serotonin and norepinephrine reuptake inhibitor (75 mg daily); or placebo for 11 days. Physiological testing performed on days 8–11included scintigraphic assessment of gastrointestinal and colonic transit, the nutrient drink test, and assessment of the postprandial change in gastric volume. Fifty-one healthy adults (40 females, 11 males) participated in this study. No effects on gastric emptying or colonic transit were identified with any agent. Small bowel transit of a solid meal was accelerated by paroxetine. Buspirone decreased postprandial aggregate symptom and nausea scores. Venlafaxine-XR increased the postprandial change in gastric volume. Buspirone, paroxetine, and venlafaxine-XR affect upper gastrointestinal functions in healthy humans. These data support the need for clinical and physiological studies of these agents in functional gastrointestinal disorders.

scholarly journals RAID-6Plus: A Comprised Methodology for Extending RAID-6 Codes

2017 ◽  
Vol 2017 ◽  
pp. 1-12 ◽  
Author(s):  
Ming-Zhu Deng ◽  
Nong Xiao ◽  
Song-Ping Yu ◽  
Fang Liu ◽  
Lingyu Zhu ◽  
...  
Keyword(s):  
Real World ◽  
Load Balance ◽  
Underlying Mechanism ◽  
Patterns Of Failure ◽  
The Third ◽  
Real World Applications ◽  
Failure Scenario ◽  
Reliability Performance ◽  
Occurrence Patterns

Existing RAID-6 code extensions assume that failures are independent and instantaneous, overlooking the underlying mechanism of multifailure occurrences. Also, the effect of reconstruction window is ignored. Additionally, these coding extensions have not been adapted to occurrence patterns of failure in real-world applications. As a result, the third parity drive is set to handle the triple-failure scenario; however, the lower level failure situations have been left unattended. Therefore, a new methodology of extending RAID-6 codes named RAID-6Plus with better compromise has been studied in this paper. RAID-6Plus (Deng et al., 2015) employs short combinations which can greatly reuse overlapped elements during reconstruction to remake the third parity drive. A sample extension code called RDP+ is given based on RDP. Moreover, we extended the study to present another extension example called X-code+ which has better update penalty and load balance. The analysis shows that RAID-6Plus is a balanced tradeoff of reliability, performance, and practicality. For instance, RDP+ could achieve speedups as high as 33.4% in comparison to the RTP with conventional rebuild, 11.9% in comparison to RTP with the optimal rebuild, 47.7% in comparison to STAR with conventional rebuild, and 26.2% for a single failure rebuild.

scholarly journals Efficacy and Safety of AVP-21D9, an Anthrax Monoclonal Antibody, in Animal Models and Humans

2014 ◽  
Vol 58 (7) ◽  
pp. 3618-3625 ◽  
Author(s):  
Nina V. Malkevich ◽  
Robert J. Hopkins ◽  
Edward Bernton ◽  
Gabriel T. Meister ◽  
Eric M. Vela ◽  
...  
Keyword(s):  
Monoclonal Antibody ◽  
Animal Models ◽  
Half Life ◽  
Healthy Human ◽  
Serious Adverse Events ◽  
Maximum Serum ◽  
Content Type ◽  
Elimination Half Life ◽  
Healthy Humans ◽  
Elimination Half

ABSTRACTAnthrax is an acute infectious disease caused by the spore-forming bacteriumBacillus anthracis. Timely administration of antibiotics approved for the treatment of anthrax disease may prevent associated morbidity and mortality. However, any delay in initiating antimicrobial therapy may result in increased mortality, as inhalational anthrax progresses rapidly to the toxemic phase of disease. An anthrax antitoxin, AVP-21D9, also known as Thravixa (fully human anthrax monoclonal antibody), is being developed as a therapeutic agent against anthrax toxemia. The efficacy of AVP-21D9 inB. anthracis-infected New Zealand White rabbits and in cynomolgus macaques was evaluated, and its safety and pharmacokinetics were assessed in healthy human volunteers. The estimated mean elimination half-life values of AVP-21D9 in surviving anthrax-challenged rabbits and nonhuman primates (NHPs) ranged from approximately 2 to 4 days and 6 to 11 days, respectively. In healthy humans, the mean elimination half-life was in the range of 20 to 27 days. Dose proportionality was observed for the maximum serum concentration (Cmax) of AVP-21D9 and the area under the concentration-time curve (AUC). In therapeutic efficacy animal models, treatment with AVP-21D9 resulted in survival of up to 92% of the rabbits and up to 67% of the macaques. Single infusions of AVP-21D9 were well tolerated in healthy adult volunteers across all doses evaluated, and no serious adverse events were reported. (This study has been registered at ClinicalTrials.gov under registration no. NCT01202695.)

Low O2-induced ATP release from erythrocytes of humans with type 2 diabetes is restored by physiological ratios of C-peptide and insulin

2014 ◽  
Vol 307 (7) ◽  
pp. R862-R868 ◽  
Author(s):  
Jennifer P. Richards ◽  
Gina L. C. Yosten ◽  
Grant R. Kolar ◽  
Cory W. Jones ◽  
Alan H. Stephenson ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Tissue Oxygenation ◽  
Atp Release ◽  
Peripheral Vascular ◽  
Healthy Human ◽  
C Peptide ◽  
Beneficial Effects ◽  
Glucose Levels ◽  
Healthy Humans

ATP release from erythrocytes in response to reduced oxygen (O2) tension stimulates local vasodilation, enabling these cells to direct perfusion to areas in skeletal muscle in need of O2. Erythrocytes of humans with type 2 diabetes do not release ATP in response to low O2. Both C-peptide and insulin individually inhibit low O2-induced ATP release from healthy human erythrocytes, yet when coadministered at physiological concentrations and ratios, no inhibition is seen. Here, we determined: that 1) erythrocytes of healthy humans and humans with type 2 diabetes possess a C-peptide receptor (GPR146), 2) the combination of C-peptide and insulin at physiological ratios rescues low O2-induced ATP release from erythrocytes of humans with type 2 diabetes, 3) residual C-peptide levels reported in humans with type 2 diabetes are not adequate to rescue low O2-induced ATP release in the presence of 1 nM insulin, and 4) the effects of C-peptide and insulin are neither altered by increased glucose levels nor explained by changes in erythrocyte deformability. These results suggest that the addition of C-peptide to the treatment regimen for type 2 diabetes could have beneficial effects on tissue oxygenation, which would help to ameliorate the concomitant peripheral vascular disease.

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