Search results for " Stimulus"

Spontaneous Cingulate High-Current Spikes Signal Normal and Pathological Pain States

2019

Prominent 7–12 Hz oscillations in frontal cortical networks in rats have been reported. However, the mechanism of generation and the physiological function of this brain rhythm have not yet been clarified. Multichannel extracellular field potentials of the ACC were recorded and analyzed using the current source density method in halothane-anesthetized rats. Spontaneous high-current spikes (HCSs) were localized in the deep part of layer II/III and upper part of layer V of the ACC. The frequency of HCSs in the ACC was 7–12 Hz, with an amplitude of 6.5 ± 0.76 mV/mm(2) and duration of 55.24 ± 2.43 ms. The power density significantly decreased (84.56 ± 6.93%, p < 0.05, t test) after pinching the…

Influence of spatial information on responses of tonically active neurons in the monkey striatum.

2006

Influence of spatial information on responses of tonically active neurons in the monkey striatum. J Neurophysiol 95: 2975–2986, 2006. First published February 8, 2006; doi:10.1152/jn.01113.2005. Previous studies have demonstrated that tonically active neurons (TANs) in the primate striatum play an important role in the detection of rewarding events. However, the influence of the spatial features of stimuli or actions required to obtain reward remains unclear. Here, we examined the activity of TANs in the striatum of monkeys trained to make spatially directed movements elicited by visual stimuli presented ipsilaterally or contralaterally to the moving arm. Among 181 neurons responding to the…

Phase-locked hippocampal theta-band responses are related to discriminative eyeblink conditioned responding

2013

Hippocampal electrophysiological oscillatory activity is undoubtedly related to learning and memory. The relative power of spontaneously occurring hippocampal theta (∼4-8 Hz) oscillations predicts how fast and how well an animal will learn: more theta predicts faster acquisition of the conditioned response in eyeblink conditioning in both rats and rabbits. Here, our aim was to study how hippocampal theta-band responses to conditioned stimuli elicited during very-long delay discrimination eyeblink conditioning relate to the accompanying conditioned behavior. We trained adult male New Zealand White rabbits using 1500-ms auditory stimuli as conditioned stimuli and a 100-ms airpuff as an uncond…

Newborn Infant Parasympathetic Evaluation Index for the Assessment of Procedural Pain in Nonanesthetized Infants: A Multicenter Pilot Study

2020

Abstract Objective The aim of this study is to evaluate the ability of the Newborn Infant Parasympathetic Evaluation (NIPE) index to detect the response to nociceptive stimuli in nonanesthetized infants and to compare these results to simultaneous scoring by behavioral scales. Study Design Thirty-six nonanesthetized infants admitted to neonatal/pediatric intensive care unit (N/PICUs) were enrolled to the study. Due to faulty records of the data, three patients had to be excluded. To detect pain caused by noxious stimuli, the heart-rate-variability-derived NIPE index and behavioral pain scales designed for measuring procedural pain in nonverbal children were used. Results Forty-one painful e…

Large-scale brain networks emerge from dynamic processing of musical timbre, key and rhythm

2012

We investigated the neural underpinnings of timbral, tonal, and rhythmic features of a naturalistic musical stimulus. Participants were scanned with functional Magnetic Resonance Imaging (fMRI) while listening to a stimulus with a rich musical structure, a modern tango. We correlated temporal evolutions of timbral, tonal, and rhythmic features of the stimulus, extracted using acoustic feature extraction procedures, with the fMRI time series. Results corroborate those obtained with controlled stimuli in previous studies and highlight additional areas recruited during musical feature processing. While timbral feature processing was associated with activations in cognitive areas of the cerebel…

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…

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

2002

The endocannabinoid system: emotion, learning and addiction

2008

The identification of the cannabinoid receptor type 1 (CB1 receptor) was the milestone discovery in the elucidation of the behavioural and emotional responses induced by the Cannabis sativa constituent Delta(9)-tetrahydrocannabinol. The subsequent years have established the existence of the endocannabinoid system. The early view relating this system to emotional responses is reflected by the fact that N-arachidonoyl ethanolamine, the pioneer endocannabinoid, was named anandamide after the Sanskrit word 'ananda', meaning 'bliss'. However, the emotional responses to cannabinoids are not always pleasant and delightful. Rather, anxiety and panic may also occur after activation of CB1 receptors.…

Common and separable behavioral and neural mechanisms underlie the generalization of fear and disgust

2021

Generalization represents the transfer of a conditioned responses to stimuli that resemble the conditioned stimulus (CS). Previous studies on generalization of defensive avoidance responses have primarily focused on fear and have neglected disgust generalization, which represents a key pathological mechanism in some anxiety disorders. In the present study we examined common and distinct mechanisms of fear and disgust generalization by means of a fear or disgust multi-CS conditioning and generalization paradigm with concomitant event-related potential (ERPs) acquisition in n = 62 subjects. We demonstrate that compared to fear, disgust-relevant generalized stimuli (GS) elicited larger expecta…

Fiscal Adjustments and Business Cycle Synchronization

2013

Using a panel of annual data for 20 countries we show that synchronized fiscal consolidation (stimulus) programmes in different countries make their business cycles more closely linked, especially in the case of fiscal adjustments lasting 2 or 3 years. We also find: (i) little evidence of decoupling when an inflation targeting regime is unilaterally adopted; (ii) an increase in business cycle synchronization when countries fix their exchange rates and become members of a monetary union; (iii) a positive effect of bilateral trade on the synchronization of business cycles