The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Ezequiel Morsella - One of the best experts on this subject based on the ideXlab platform.
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The reflexive imagery task: An Experimental Paradigm for neuroimaging
AIMS Press, 2018Co-Authors: Hyein Cho, Wei Dou, Zaviera Reyes, Mark W. Geisler, Ezequiel MorsellaAbstract:High-level cognitions can be triggered into consciousness through the presentation of external stimuli and the activation of certain action sets. These activations arise in a manner that is involuntary, systematic and nontrivial. For example, in the Reflexive Imagery Task (RIT), subjects are presented with visual objects and instructed to not think of the names of the objects. Involuntary subvocalizations arise on roughly 80% of the trials. We review the findings from this Paradigm, discuss neural findings that are relevant to the RIT, and present new data that further corroborate the reliability and robustness of the RIT, a Paradigm that could be coupled with neuroimaging technologies. We developed an RIT variant in which two, non-focal objects are presented simultaneously. In previous RITs, visual objects were presented only one at a time, in the center of the screen, and subjects were instructed to focus on the center of the screen, where these objects were presented. Replicating the RIT effect, involuntary subvocalizations still occurred on a high proportion of trials (M = 0.78). An RIT effect arose for both objects on a considerable proportion of the trials (M = 0.35). These findings were replicated in a second experiment having a different sample of subjects. Our findings are relevant to many subfields of neuroscience (e.g., the study of high-level mental processes, attention, imagery and action control)
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conscious thoughts from reflex like processes a new Experimental Paradigm for consciousness research
Consciousness and Cognition, 2013Co-Authors: Allison K Allen, Ezequiel Morsella, Kevin B Wilkins, Adam GazzaleyAbstract:The contents of our conscious mind can seem unpredictable, whimsical, and free from external control. When instructed to attend to a stimulus in a work setting, for example, one might find oneself thinking about household chores. Conscious content thus appears different in nature from reflex action. Under the appropriate conditions, reflexes occur predictably, reliably, and via external control. Despite these intuitions, theorists have proposed that, under certain conditions, conscious content resembles reflexes and arises reliably via external control. We introduce the Reflexive Imagery Task, a Paradigm in which, as a function of external control, conscious content is triggered reliably and unintentionally: When instructed to not subvocalize the name of a stimulus object, participants reliably failed to suppress the set-related imagery. This stimulus-elicited content is considered ‘high-level’ content and, in terms of stages of processing, occurs late in the processing stream. We discuss the implications of this Paradigm for consciousness research.
Anurag Kuhad - One of the best experts on this subject based on the ideXlab platform.
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resveratrol suppresses neuroinflammation in the Experimental Paradigm of autism spectrum disorders
Neurochemistry International, 2017Co-Authors: Ranjana Bhandari, Anurag KuhadAbstract:Abstract Background Neuronal dysfunction caused by neuroinflammation triggered by the stimulation of matrix metalloproteinases and the subsequent release of pro-inflammatory cytokines, as a result of oxidative stress and mitochondrial dysfunction, is one of the probable mechanisms involved in the pathogenesis of autism spectrum disorders (ASD). The aim of the present study was to explore the ameliorative potential of resveratrol on neuroinflammation in the Experimental Paradigm of neuroinflammatory model of ASD in rats. Method 1M Propanoic acid (PPA) (4 μl) was infused over 10 min into the anterior portion of the lateral ventricle to induce ASD like symptoms in rats. Resveratrol (5, 10 and 15 mg/kg) was administered starting from the 2nd day of the surgery and continued upto 28th day. Rats were tested for various behavioural Paradigms such as social interaction, stereotypy, locomotor activity, anxiety, novelty, depression, spatial learning, memory, repetitive and pervasive behaviour between the 7th day and 28th day. In addition, biochemical tests for oxidative stress, mitochondrial complexes, TNF-α and MMP-9 were also assessed. Results Treatment with resveratrol for four weeks restored, significantly and dose dependently, all the neurological, sensory, behavioural, biochemical and molecular deficits in PPA induced autistic phenotype in rats. Conclusion The major finding of the study is that resveratrol restored the core and associated symptoms of autistic phenotype by suppressing oxidative-nitrosative stress, mitochondrial dysfunction, TNF-α and MMP-9 expression in PPA induced ASD in rats. Therefore, resveratrol might serve as an adjunct potential therapeutic agent for amelioration of neurobehavioural and biochemical deficits associated with autism spectrum disorders.
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neuropsychopharmacotherapeutic efficacy of curcumin in Experimental Paradigm of autism spectrum disorders
Life Sciences, 2015Co-Authors: Ranjana Bhandari, Anurag KuhadAbstract:Neuroinflammatory response triggered by the stimulation of matrix metalloproteinases plays a pivotal role in the development of autistic phenotype. MMPs stimulate inflammatory cytokines release along with mitochondrial deficits that ultimately lead to neuronal dysfunction and precipitate autistic symptoms. The aim of the present study was to explore the neuropsychopharmacotherapeutic efficacy of curcumin in the Experimental Paradigm of autism spectrum disorders.1M propanoic acid (4μl) was infused over 10min into the anterior portion of the caudoputamen to induce autistic behavior in rats. Curcumin (50, 100 and 200mg/kg) was administered per orally starting from 2nd day of surgery and continued up to 28th day. Rats were tested for various neurobehavioural Paradigms like social interaction, stereotypy, locomotor activity, anxiety, novelty, depression, spatial learning and memory as well as for repetitive and pervasive behavior. In addition, biochemical tests for oxidative stress, mitochondrial complexes, TNF-α and MMP-9 were also carried out.Intracerebroventricular injection of propanoic acid produced neurological, sensory, behavioral, biochemical and molecular deficits which were assessed as endophenotype of autism spectrum disorders. Regular treatment with curcumin for four weeks significantly and dose dependently restored neurological, behavioral, biochemical and molecular changes associated with autistic phenotype in rats.The major finding of the study is that curcumin restored the core and associated symptoms of autistic phenotype by suppressing oxidative-nitrosative stress, mitochondrial dysfunction, TNF-α and MMP-9 in PPA-induced autism in rats. Therefore, curcumin can be developed as a potential neuropsychopharmacotherapeutic adjunct for autism spectrum disorders (ASD).
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naringin ameliorates memory deficits in Experimental Paradigm of alzheimer s disease by attenuating mitochondrial dysfunction
Pharmacology Biochemistry and Behavior, 2014Co-Authors: Anand Kamal Sachdeva, Anurag Kuhad, Kanwaljit ChopraAbstract:Abstract Rationale Mitochondrial dysfunction has been well documented in age related disorders like Alzheimer's disease. Alterations in mitochondrial membrane potential lead to neuronal death by excessive generation of free radicals, inflammatory cytokines, and excitotoxins. Intracerebroventricular (ICV) streptozotocin (STZ) induced-cognitive impairment has been widely used as an Experimental model of Alzheimer's disease. Naringin is a potent antioxidant, which can cross the blood brain barrier protecting brain tissue and modulating brain chemistry. Objectives The present study was designed to evaluate the effect of naringin, in ICV STZ-induced mitochondrial dysfunction and memory loss in rats. Methods Streptozotocin (3 mg/kg, ICV) was injected bilaterally in two divided doses on first and third day followed by treatment with different doses of naringin (50, 100 and 200 mg/kg; p.o.) for twenty one days. Behavioral alterations were monitored using Morris water maze Paradigm and elevated plus maze test. Animals were sacrificed to evaluate various biochemical and mitochondrial parameters in brain. Rivastigmine was used as a standard drug. Results ICV-STZ administration produced significant cognitive deficits as assessed by both Morris water maze and elevated plus maze task which is accompanied by significantly enhanced oxidative-nitrosative stress, altered acetylcholinesterase and mitochondrial enzyme activities in cerebral cortex and hippocampus of rats brain along with significantly increased brain TNF-α and IL-1β levels. Chronic treatment with naringin dose dependently restored cognitive deficits in ICV-STZ rat along with mitigation of mitochondrial dysfunction mediated oxido-nitrosative stress and cytokine release. Conclusions Our findings demonstrate that naringin ameliorates mitochondrial dysfunction mediated oxido-nitrosative stress and inflammatory surge in ICV-STZ rats.
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neurobiological effect of 7 nitroindazole a neuronal nitric oxide synthase inhibitor in Experimental Paradigm of alzheimer s disease
Indian Journal of Experimental Biology, 2013Co-Authors: Shubham Misra, Anurag Kuhad, Kanwaljit ChopraAbstract:: Nitric oxide plays a role in a series of neurobiological functions, underlying behaviour and memory. The functional role of nNOS derived nitric oxide in cognitive functions is elusive. The present study was designed to investigate the effect of specific neuronal nitric oxide synthase inhibitor, 7-nitroindazole, against intracerebroventricular streptozotocin-induced cognitive impairment in rats. Learning and memory behaviour was assessed using Morris water maze and elevated plus maze. 7-nitroindazole (25 mg/kg, ip) was administered as prophylactically (30 min before intracerebroventricular streptozotocin injection on day 1) and therapeutically (30 min before the assessment of memory by Morris water maze on day 15). Intracerebroventricular streptozotocin produced significant cognitive deficits coupled with alterations in biochemical indices.These behavioural and biochemical changes were significantly prevented by prophylactic treatment of 7-nitroindazole. However, therapeutic intervention of 7-nitroindazole did not show any significant reversal. The results suggests that 7-nitroindazole can be effective in the protection of dementiainduced by intracerebroventricular streptozotocin only when given prophylactically but not therapeutically.
Wayne D. Gray - One of the best experts on this subject based on the ideXlab platform.
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Meta-T: Tetris^Ⓡ as an Experimental Paradigm for cognitive skills research
Behavior Research Methods, 2015Co-Authors: John K. Lindstedt, Wayne D. GrayAbstract:Studies of human performance in complex tasks using video games are an attractive prospect, but many existing games lack a comprehensive way to modify the game and track performance beyond basic levels of analysis. Meta-T provides experimenters a tool to study behavior in a dynamic task environment with time-stressed decision-making and strong perceptual-motor elements, offering a host of Experimental manipulations with a robust and detailed logging system for all user events, system events, and screen objects. Its experimenter-friendly interface provides control over detailed parameters of the task environment without need for programming expertise. Support for eye-tracking and computational cognitive modeling extend the Paradigm’s scope.
Colin M Brown - One of the best experts on this subject based on the ideXlab platform.
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syntactic processing in left prefrontal cortex is independent of lexical meaning
NeuroImage, 2001Co-Authors: Peter Indefrey, Peter Hagoort, Hans Herzog, Rudiger J Seitz, Colin M BrownAbstract:In language comprehension a syntactic representation is built up even when the input is semantically uninterpretable. We report data on brain activation during syntactic processing, from an experiment on the detection of grammatical errors in meaningless sentences. The Experimental Paradigm was such that the syntactic processing was distinguished from other cognitive and linguistic functions. The data reveal that in syntactic error detection an area of the left dorsolateral prefrontal cortex, adjacent to Broca's area, is specifically involved in the syntactic processing aspects, whereas other prefrontal areas subserve general error detection processes.
John K. Lindstedt - One of the best experts on this subject based on the ideXlab platform.
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Meta-T: Tetris^Ⓡ as an Experimental Paradigm for cognitive skills research
Behavior Research Methods, 2015Co-Authors: John K. Lindstedt, Wayne D. GrayAbstract:Studies of human performance in complex tasks using video games are an attractive prospect, but many existing games lack a comprehensive way to modify the game and track performance beyond basic levels of analysis. Meta-T provides experimenters a tool to study behavior in a dynamic task environment with time-stressed decision-making and strong perceptual-motor elements, offering a host of Experimental manipulations with a robust and detailed logging system for all user events, system events, and screen objects. Its experimenter-friendly interface provides control over detailed parameters of the task environment without need for programming expertise. Support for eye-tracking and computational cognitive modeling extend the Paradigm’s scope.
