Search results for "STIMULATION"
showing 10 items of 2192 documents
ERP correlates of transposed-letter priming effects: The role of vowels versus consonants
2008
One key issue for any computational model of visual-word recognition is the choice of an input coding scheme for assigning letter position. Recent research has shown that pseudowords created by transposing two letters are very effective at activating the lexical representation of their base words (e.g., relovution activates REVOLUTION). We report a masked priming lexical decision experiment in which the pseudoword primes were created by transposing/replacing two consonants or two vowels while event-related potentials were recorded. The results showed a modulation of the amplitude at an early window (150-250 ms) and at the N400 component for vowels but not for consonant transpositions. In ad…
Does the proportion of associatively related pairs modulate the associative priming effect at very brief stimulus-onset asynchronies?
2002
A number of experiments have shown that the magnitude of the associative priming effect increases substantially when there is a high proportion of associatively related pairs in the list when the stimulus-onset asynchrony (SOA) between prime and target is long (more than 400 ms). In the present series of experiments we manipulated the proportion of associatively related pairs when the SOA was very brief (less than 200 ms). If processing of a target word is facilitated automatically by the prior presentation of a related prime, the occurrence of priming should be unaffected by the proportion of related pairs in the list. Experiment 1 showed a robust relatedness proportion effect obtained in …
The influence of temporal factors on automatic priming and conscious expectancy in a simple reaction time task.
2009
In a previous study, we reported a dissociation between subjective expectancy and motor behaviour in a simple associative learning task (Perruchet, Cleeremans, & Destrebecqz, 2006). According to previous conditioning studies (Clark, Manns, & Squire, 2001), this dissociation is observed when the to-be-associated events coterminate and thus overlap in time (a training regimen called delay conditioning), but not when they are separated by a temporal delay (trace conditioning). In this latter situation indeed, there tends to be a direct relationship between subjective expectancy and behaviour. In this study, we further investigated this issue in a series of experiments where conscious …
GH responses to two consecutive bouts of neuromuscular electrical stimulation in healthy adults.
2008
BackgroundIt is well established that repeated GHRH administration or repeated voluntary exercise bouts are associated with a complete blunting of GH responsiveness when the administration of the second stimulus follows the first one after a 2-h interval.AimTo evaluate GH responses to neuromuscular electrical stimulation (NMES) in healthy adults.MethodsSix volunteers (mean age±s.d. 31.7±5.5 years) were studied before and after two consecutive bouts of NMES exercise (a series of 20 contractions at the maximum of individual tolerance, frequency: 75 Hz, pulse duration: 400 μs, on–off ratio: 6.25–20 s) administered at a 2-h interval.ResultsBaseline GH levels (mean: 0.3±0.2 ng/ml) significantly …
Sound-Induced Flash Illusions Support Cortex Hyperexcitability in Fibromyalgia
2022
Objectives. Fibromyalgia (FM) is characterized by spontaneous chronic widespread pain in combination with hyperalgesia to pressure stimuli. Sound-induced flash illusions (SIFIs) reflect cross-modal interactions between senses allowing to assess a visual cortical hoerexcitability (VCH) by evaluating the fission and fusion illusions disruption. The aims of the present study were to explore whether SIFIs are perceived differently in patients with fibromyalgia as compared to healthy controls (HCs) and how migraine affects fission and fusion illusions in fibromyalgia. Methods. A single flash (F) accompanied by 0 to 4 beeps (B) was presented to induce the fission illusion while multiple flash (i.…
Detection of sound rise time by adults with dyslexia
2005
Low sensitivity to amplitude modulated (AM) sounds is reported to be associated with dyslexia. An important aspect of amplitude modulation cycles are the rise and fall times within the sound. In this study, simplified stimuli equivalent to just one cycle were used and sensitivity to varying rise times was explored. Adult participants with dyslexia or compensated dyslexia and a control group performed a detection task with sound pairs of different rise times. Results showed that the participants with dyslexia differed from the control group in rise time detection and a correlation was found between rise time detection and reading and phonological skills. A subgroup of participants with lower…
Prevalence of late-onset 11 β-hydroxylase-deficiency in hirsute patients
1988
Serum levels of 11-deoxycortisol were determined in 182 hirsute women. Three patients presented high basal 11-deoxycortisol levels and an exaggerated response of this steroid to ACTH stimulation. A fourth patient had normal basal 11-deoxycortisol but was hyperresponsive to ACTH stimulation. Therefore diagnosis of late-onset 11 beta-hydroxylase deficiency was made in 4 out of 182 hirsute women with a prevalence of 2.2% in the group studied. In these patients, clinical findings and other hormonal patterns were not different from those of other women suffering from hirsutism.
Obesity and poor reproductive outcome: the potential role of the endometrium
2007
Objective To analyze the potential role of extraovarian factors such as endometrium in the reproductive outcome of obese patients. Design Retrospective study. Setting University-affiliated infertility clinic, between January 2001 and July 2005. Patient(s) Women undergoing a total of 2656 first ovum donation (OD) cycles with good quality embryos. Intervention(s) The oocyte donors underwent controlled ovarian hyperstimulation, and recipients received a well-established hormonal replacement therapy for endometrial preparation. In vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) was performed according to semen characteristics. All first cycles (n = 2656) of ovum donation us…
Impact of luteinizing hormone administration on gonadotropin-releasing hormone antagonist cycles: an age-adjusted analysis
2011
Objective: To analyze the impact of LH administration on cycle outcome in ovarian stimulation with GnRH antagonists. Design: Randomized, open-label, controlled trial performed in two age subgroups. Recombinant (r) FSH versus rFSH + rLH administration was compared. Setting: University-affiliated private infertility clinic. Patient(s): Up to 35 years old (n = 380) and aged 36 to 39 years (n = 340), undergoing their first or second IVF cycle. Intervention(s): Recombinant LH administration since stimulation day 1. Main Outcome Measure(s): Implantation rate, ongoing pregnancy rate. Result(s): In the young population, implantation rates were similar: 27.8% versus 28.6%, odds ratio (OR) 1.03 (95% …
Lateralization of directional brain-heart information transfer during visual emotional elicitation
2019
Previous studies have characterized the physiological interactions between central nervous system (brain) and peripheral cardiovascular system (heart) during affective elicitation in healthy subjects; however, questions related to the directionality of this functional interplay have been gaining less attention from the scientific community. Here, we explore brain-heart interactions during visual emotional elicitation in healthy subjects using measures of Granger causality (GC), a widely used descriptor of causal influences between two dynamical systems. The proposed approach inferences causality between instantaneous cardiovagal dynamics estimated from inhomogeneous point-process models of…