Search results for "Process"
showing 10 items of 22310 documents
Neural Correlates of Visual versus Abstract Letter Processing in Roman and Arabic Scripts
2013
In alphabetic orthographies, letter identification is a critical process during the recognition of visually presented words. In the present experiment, we examined whether and when visual form influences letter processing in two very distinct alphabets (Roman and Arabic). Disentangling visual versus abstract letter representations was possible because letters in the Roman alphabet may look visually similar/dissimilar in lowercase and uppercase forms (e.g., c-C vs. r-R) and letters in the Arabic alphabet may look visually similar/dissimilar, depending on their position within a word (e.g., [Formula: see text] - [Formula: see text] vs. [Formula: see text] - [Formula: see text]). We employed a…
Timing flickers across sensory modalities
2009
In tasks requiring a comparison of the duration of a reference and a test visual cue, the spatial position of test cue is likely to be implicitly coded, providing a form of a congruency effect or introducing a response bias according to the environmental scale or its vectorial reference. The precise mechanism generating these perceptual shifts in subjective duration is not understood, although several studies suggest that spatial attentional factors may play a critical role. Here we use a duration comparison task within and across sensory modalities to examine if temporal performance is also modulated when people are exposed to spatial distractors involving different sensory modalities. Di…
1 Hz rTMS enhances extrastriate cortex activity in migraine
2003
We recently reported a paradoxical facilitatory effect of 1 Hz repetitive TMS (rTMS) on the primary visual cortex in migraine possibly due to the failure of inhibitory circuits, unable to be upregulated by low frequency rTMS. To investigate if inhibitory circuit dysfunction extends beyond striate cortex in migraine with aura, we studied the effects of 1 Hz rTMS over the right extrastriate cortex on perception of illusory contours in these patients. Low-frequency rTMS enhanced activity of extrastriate cortex in migraineurs, speeding up reaction times on illusory contour perception. This finding supports the view of a failure of inhibitory circuits also involving the extrastriate cortex in mi…
COMT genotype predicts BOLD signal and noise characteristics in prefrontal circuits.
2006
Abstract Objective: Prefrontal dopamine (DA) is catabolized by the COMT (catechol- O -methyltransferase) enzyme. Literature suggests that the Val/Met single nucleotide polymorphism (SNP) in the COMT gene predicts executive cognition in humans with Val carriers showing poorer performance due to less available synaptic DA. Recent fMRI studies are thought to agree with these studies having demonstrated prefrontal hyperactivation during n -back and attention-requiring tasks. This was interpreted as “less efficient” processing due to impaired signal-to-noise ratio (SNR) of neuronal activity. However, electrophysiological studies of neuronal SNR in primates and humans imply that prefrontal cortex…
Anger superiority effect for change detection and change blindness
2013
Abstract In visual search, an angry face in a crowd “pops out” unlike a happy or a neutral face. This “anger superiority effect” conflicts with views of visual perception holding that complex stimulus contents cannot be detected without focused top-down attention. Implicit visual processing of threatening changes was studied by recording event-related potentials (ERPs) using facial stimuli using the change blindness paradigm, in which conscious change detection is eliminated by presenting a blank screen before the changes. Already before their conscious detection, angry faces modulated relatively early emotion sensitive ERPs when appearing among happy and neutral faces, but happy faces only…
A meta-analysis of the health action process approach.
2019
Objective The health action process approach (HAPA) is a social-cognitive model specifying motivational and volitional determinants of health behavior. A meta-analysis of studies applying the HAPA in health behavior contexts was conducted to estimate the size and variability of correlations among model constructs, test model predictions, and test effects of past behavior and moderators (behavior type, sample type, measurement lag, study quality) on model relations. Method A literature search identified 95 studies meeting inclusion criteria with 108 independent samples. Averaged corrected correlations among HAPA constructs and multivariate tests of model predictions were computed using conve…
Changes in physical activity among coronary and hypertensive patients: A longitudinal study using the Health Action Process Approach
2017
Objectives: Physical activity (PA) is a key factor in cardiovascular disease prevention. Through the Health Action Process Approach (HAPA), the present study investigated the process of change in PA in coronary patients (CPs) and hypertensive patients (HPs). Design: Longitudinal survey study with two follow-up assessments at 6 and 12 months on 188 CPs and 169 HPs. Main outcome measures: Intensity and frequency of PA. Results: A multi-sample analysis indicated the equivalence of almost all the HAPA social cognitive patterns for both patient populations. A latent growth curve model showed strong interrelations among intercepts and slopes of PA, planning and maintenance self-efficacy, but chan…
Anodal transcranial direct current stimulation of the right dorsolateral prefrontal cortex enhances memory-guided responses in a visuospatial working…
2014
Several studies have shown that transcranial direct current stimulation (tDCS) is able to enhance performances on verbal and visual working memory (WM) tasks. Available evidence points to the right dorsolateral prefrontal cortex (DLPFC) as a critical area in visual WM, but to date direct comparisons of the effects obtained by stimulating the left versus the right DLPFC in the same subject are lacking. Our aim was to determine whether tDCS over the right DLPFC can differently affect performance as compared with left DLPFC stimulation. Ten healthy subjects performed a memory-guided visuospatial task in three conditions: baseline, during anodal stimulation applied over the right and during ano…
Learning at the breast: Preference formation for an artificial scent and its attraction against the odor of maternal milk
2006
International audience; Human newborns are known to display spontaneous attraction to the odor of human milk. This study aimed to assess whether the positive response to human milk odor can be explained by nursing-related learning, and whether it can be easily reassigned to a novel odor associated with nursing. Infants were exposed or not to a novel odor (camomile, Ca) during nursing, and tested on day 3–4 for their preference for camomile in comparison with either a scentless control (Exp. 1), a scented control (Exp. 2), or maternal milk (Exp. 3). Prior experience with Ca modified the newborns’ responses. While the Ca odor became more attractive than a scented control in the Ca-exposed gro…
Long-Term Drug Misuse Increases the Risk of Cognitive Dysfunctions in Intimate Partner Violence Perpetrators: Key Intervention Targets for Reducing D…
2019
Intimate partner violence against women (IPVAW) is a major public health problem, with an important mortality rate in women across the world. In this regard, it has been well-established that drug misuse explains (at least in part) an increased risk of IPVAW perpetration. Even though alcohol is the most widely studied drug underlying IPVAW, other drugs, such as cannabis and cocaine also seem to be significant indicators of this type of violence. Nonetheless, little is known about mediators, such as cognitive domains that facilitate proneness to violence after drug consumption. Therefore, the primary objective of the present study was to compare drug misuse patterns and cognitive performance…