Search results for "Stimulus"

Neurons in the pigeon nidopallium caudolaterale signal the selection and execution of perceptual decisions

2014

Sensory systems provide organisms with information on the current status of the environment, thus enabling adaptive behavior. The neural mechanisms by which sensory information is exploited for action selection are typically studied with mammalian subjects performing perceptual decision-making tasks, and most of what is known about these mechanisms at the single-neuron level is derived from cortical recordings in behaving monkeys. To explore the generality of neural mechanisms underlying perceptual decision making across species, we recorded single-neuron activity in the pigeon nidopallium caudolaterale (NCL), a non-laminated associative forebrain structure thought to be functionally equiva…

Study on the transient characteristic in the human visual system using masking experiments

1979

In this paper the visual masking effect is interpreted on the basic of the transient characteristic in two dimensional neuronal networks. The study investigates the suitability of the effect for use as a measurement method. It is shown that the stimulus distribution in space can be scanned at different points in time and that various dynamic characteristic values of the system can be measured.

Time response of the vision binocularity by use of dynamic suppression of retinal images

1999

We present a novel technique for determination the stereopsis dynamic response, using as stimulus a random dot stereopair. Stereopsis can be evoked or depressed by continuous or flash illumination of the stimulus with simultaneous control of a special light scattering obstacle build in the visual path of one eye. The obstacle--a thin plate of electrooptical PLZT ceramics-- exposes (by applying of the voltage to semitransparent gold electrodes deposited on both surfaces of the plate) light scattering so blurring the retinal image, similar as for an eye with a cataract, depressing stereopsis. The random dot stereopair contains contours of images with a different stereodisparity. The PLZT plat…

The Role of Perceived Control in the Psychophysiological Responses to Disgust of Subclinical OCD Women

2019

Obsessive‒compulsive disorder (OCD), and especially contamination obsessions and washing compulsions, has been related to disgust. However, when its cardiovascular correlates have been studied, contradictory results have been found, including heart rate accelerations and decelerations. The aim of this study is to analyze emotional, cognitive, and cardiovascular responses in nonclinical (control) and subclinical participants with obsessive‒compulsive contamination/washing symptoms when confronted with a disgusting stimulus. Twenty-seven participants (14 subclinical OCD) completed a behavioral avoidance task with a contamination-based stimulus while their heart rate and subjective variables w…

Back to Pupillometry: How Cortical Network State Fluctuations Tracked by Pupil Dynamics Could Explain Neural Signal Variability in Human Cognitive Ne…

2017

Visual Abstract

Naloxone inhibits not only stress-induced analgesia but also sympathetic activation and baroreceptor-reflex sensitivity

2012

Interactions between the sympathetic nervous system and pain are manifold and still have not been sufficiently characterized. Accordingly, several possible neuronal pathways have been described as being involved in mental stress-induced analgesia. We studied the role of the endogenous opioidergic system in stress-induced analgesia in 14 healthy participants in a double-blind cross-over trial. Naloxone or placebo was applied while electrical pain stimulation was started and electrical current increased. After reaching a constant stimulation at 30 mA, a color word interference test (Stroop task) was performed in a stressful and a non-stressful version. Blood pressure, heart rate and barorefle…

Investigating the impact of virtual tourism on travel intention during the post-COVID-19 era: evidence from China

2022

This study explores the mechanism that contributes to travel intention in the field of virtual tourism. The overall research method is based on the "Stimulus-Organism-Response" theory. In the research model, the effects of content quality, system quality, and interaction quality in virtual tourism on tourism experience and travel intention are explored, as well as the role of virtual attachment and travel intention. A total of 390 respondents were invited to participate in a virtual tourism experience, and provide feedback through a questionnaire. SmartPLS 3.3.2 was used to validate the causal model, and most of the study hypotheses were supported. The findings show that virtual tourism sig…

Peripheral Acute Pain Mechanisms

1995

Many studies in several species, including humans, have identified a subset of primary afferent nerve fibres that are activated by potential or actual tissue-damaging stimuli. Discharge patterns of these nociceptive afferents faithfully reproduce some aspects of the applied stimuli (e.g. shape of the stimulus-response function) but not others (e.g. time-course of a sustained stimulus). Since primary nociceptive afferents provide the input to the central nervous system, their encoding properties have to be considered when studying central processing. On the other hand, pain perception correlates with some aspects of nociceptor discharges (e.g. fatigue with repetition of brief heat pulses), b…

Pain elicited by blunt pressure: neurobiological basis and clinical relevance.

2002

Somatic Symptom Perception From a Predictive Processing Perspective: An Empirical Test Using the Thermal Grill Illusion.

2020

OBJECTIVE In a predictive processing perspective, symptom perceptions result from an integration of preexisting information in memory with sensory input. Physical symptoms can therefore reflect the relative predominance of either sensory input or preexisting information. In this study, we used the thermal grill illusion (TGI), which applies interlaced warm and cool temperatures to the skin to create a paradoxical heat-pain experience. Assuming that the TGI compared with single-temperature stimulation relies more importantly on an active integration process of the brain to create this paradoxical sensation, we tested the hypothesis whether a manipulation of the expectations during TGI would …