Search results for "Stimulus"

Prospective study of nocebo effects related to symptoms of idiopathic environmental intolerance attributed to electromagnetic fields (IEI-EMF).

2020

The exact causes of Idiopathic Environmental Intolerance Attributed to Electromagnetic Fields (IEI-EMF, i.e., experience of somatic symptoms attributed to low-level electromagnetic fields) are still unknown. Psychological causation such as nocebo effects seem plausible. This study aimed to experimentally induce a nocebo effect for somatic symptom perception and examined whether it was reproducible after one week. We also examined whether these effects were associated with increased sympathetic activity and whether interoceptive accuracy (IAcc) moderated these relationships. Participants were recruited from the general population and instructed that electromagnetic exposure can enhance somat…

2020

Interruptions (interfering stimuli to respond to) and distractions (interfering stimuli to be ignored) have been shown to negatively impact performance, particularly in tasks requiring working memory (WM). This study investigated how these two types of external interference affect task performance and attentional and WM processes as indexed by specific event-related potentials (ERPs) of the EEG. A Continuous Number Task (CNT) was applied, in which participants had to either decide whether the current number (condition without WM load) or the sum of the current and the preceding number (condition with WM load) was odd or even while responding to interlaced single letters (interruptions) or i…

Event-related potentials to unattended changes in facial expressions: detection of regularity violations or encoding of emotions?

2013

Visual mismatch negativity (vMMN), a component in event-related potentials (ERPs), can be elicited when rarely presented “deviant” facial expressions violate regularity formed by repeated “standard” faces. vMMN is observed as differential ERPs elicited between the deviant and standard faces. It is not clear, however, whether differential ERPs to rare emotional faces interspersed with repeated neutral ones reflect true vMMN (i.e., detection of regularity violation) or merely encoding of the emotional content in the faces. Furthermore, a face-sensitive N170 response, which reflects structural encoding of facial features, can be modulated by emotional expressions. Owing to its similar latency …

P 96. Prismatic lenses as a novel tool to directionally manipulate motor cortex excitability: Evidence from paired-pulse TMS

2013

Introduction Prismatic adaptation (PA) is a visuo-motor procedure requiring participants to adapt to prismatic lenses shifting the visual scene horizontally. Such an adaptation produces a phenomenon called “after-effect”, opposite to the side of lenses deviation. The after-effect has been frequently associated with a shift of spatial attention in the same direction and with a restoration of hemispatial neglect symptoms. PA has captured the interest of neuroscientists in the last decades, since it affects high-order spatial cognition even thought consisting of low-level visuo-motor processes. Objectives Despite a huge literature on this procedure, the basic neural processes related to PA and…

From different neurophysiological methods to conflicting pathophysiological views in migraine: a critical review of literature.

2014

Abnormal increased cortical responsivity to various types of stimuli plays a major role in migraine pathogenesis. Neurophysiological studies, however, have provided ambiguous findings of either hypo or hyper cortical excitability. This is why the term "dysexcitability" has been recently proposed to indicate a more general dysregulation of cortical excitability. The aims of this review are: (1) to provide existing knowledge and research advances in migraine pathophysiology; (2) to propose a unitary interpretation of apparently conflicting neurophysiological findings. Data of studies conducted in migraine through various evoked potentials techniques and non-invasive brain stimulation methods …

Hemispheric Differences in Functional Interactions Between the Dorsal Lateral Prefrontal Cortex and Ipsilateral Motor Cortex

2020

Background: The dorsolateral prefrontal cortex (DLPFC) in both hemispheres have a central integrative function for motor control and behavior. Understanding the hemispheric difference between DLPFC and ipsilateral motor cortex connection in the resting-state will provide fundamental knowledge to explain the different roles DLPFC plays in motor behavior. Purpose: The current study tested the interactions between the ipsilateral DLPFC and the primary motor cortex (M1) in each hemisphere at rest. We hypothesized that left DLPFC has a greater inhibitory effect on the ipsilateral M1 compared to the right DLPFC. Methods: Fourteen right-handed subjects were tested in a dual-coil paired-pulse parad…

Mobile money as a driver of digital financial inclusion

2023

Meeting the mobile money needs of the less privileged in developing and emerging markets opens up enormous possibilities for banks and newly emerged financial-technology firms. Many consider mobile money services a separate domain within the banking and payment sector, different from its siblings: automated teller machines, net banking, point-of-sale banking, etc. This study was conducted to investigate how mobile money services act as a reliable driver of digital financial inclusion and to determine the role of mobile money agents in the transformation from the traditional services to mobile money services. This paper presents a conceptual model based on the stimulus-organism-response para…

On application of kernel PCA for generating stimulus features for fMRI during continuous music listening

2018

Background There has been growing interest towards naturalistic neuroimaging experiments, which deepen our understanding of how human brain processes and integrates incoming streams of multifaceted sensory information, as commonly occurs in real world. Music is a good example of such complex continuous phenomenon. In a few recent fMRI studies examining neural correlates of music in continuous listening settings, multiple perceptual attributes of music stimulus were represented by a set of high-level features, produced as the linear combination of the acoustic descriptors computationally extracted from the stimulus audio. New method fMRI data from naturalistic music listening experiment were…

Fluent Speakers of a Second Language Process Graspable Nouns Expressed in L2 Like in Their Native Language

2017

According to embodied cognition, language processing relies on the same neural structures involved when individuals experience the content of language material. If so, processing nouns expressing a motor content presented in a second language should modulate the motor system as if presented in the mother tongue. We tested this hypothesis using a go-no go paradigm. Stimuli included English nouns and pictures depicting either graspable or non-graspable objects. Pseudo-words and scrambled images served as controls. Italian participants, fluent speakers of English as a second language, had to respond when the stimulus was sensitive and refrain from responding when it was not. As foreseen by emb…

Hormesis: Decoding Two Sides of the Same Coin

2015

In the paradigm of drug administration, determining the correct dosage of a therapeutic is often a challenge. Several drugs have been noted to demonstrate contradictory effects per se at high and low doses. This duality in function of a drug at different concentrations is known as hormesis. Therefore, it becomes necessary to study these biphasic functions in order to understand the mechanistic basis of their effects. In this article, we focus on different molecules and pathways associated with diseases that possess a duality in their function and thus prove to be the seat of hormesis. In particular, we have highlighted the pathways and factors involved in the progression of cancer and how t…