Contemplative practices, such as meditation and yoga, are increasingly popular among the general public and as topics of research. Beneficial effects associated with these practices have been found ...on physical health, mental health and cognitive performance. However, studies and theories that clarify the underlying mechanisms are lacking or scarce. This theoretical review aims to address and compensate this scarcity. We will show that various contemplative activities have in common that breathing is regulated or attentively guided. This respiratory discipline in turn could parsimoniously explain the physical and mental benefits of contemplative activities through changes in autonomic balance. We propose a neurophysiological model that explains how these specific respiration styles could operate, by phasically and tonically stimulating the vagal nerve: respiratory vagal nerve stimulation (rVNS). The vagal nerve, as a proponent of the parasympathetic nervous system (PNS), is the prime candidate in explaining the effects of contemplative practices on health, mental health and cognition. We will discuss implications and limitations of our model.
Cognitive demands in response conflict paradigms trigger negative affect and avoidance behavior. However, not all response conflict studies show increases in physiological indices of emotional ...arousal, such as pupil diameter. In contrast to earlier null-results, this study shows for the first time that small (about 0.02 mm) conflict-related pupil dilation can be observed in a Simon task when stimuli do not introduce a light reflex. Results show that response-conflict in Simon trials induces both pupil dilation and reaction-time costs. Moreover, sequential analyses reveal that pupil dilation mirrors the conflict-adaptation pattern observed in reaction time (RT). Although single-trial regression analyses indicated that pupil dilation is likely to reflect more than one process at the same time, in general our findings imply that pupil dilation can be used as an indirect marker of conflict processing.
We present a detailed report on sterile neutrino oscillation and 235Uν¯e energy spectrum measurement results from the PROSPECT experiment at the highly enriched High Flux Isotope Reactor (HFIR) at ...Oak Ridge National Laboratory. In 96 calendar days of data taken at an average baseline distance of 7.9 m from the center of the 85 MW HFIR core, the PROSPECT detector has observed more than 50,000 interactions of νe produced in beta decays of 235U fission products. New limits on the oscillation of ν¯e to light sterile neutrinos have been set by comparing the detected energy spectra of ten reactor-detector baselines between 6.7 and 9.2 meters. Measured differences in energy spectra between baselines show no statistically significant indication of ν¯e to sterile neutrino oscillation and disfavor the reactor antineutrino anomaly best-fit point at the 2.5σ confidence level. The reported 235U ν¯e energy spectrum measurement shows excellent agreement with energy spectrum models generated via conversion of the measured 235U beta spectrum, with a χ2/d.o.f. of 31/31. PROSPECT is able to disfavor at 2.4σ confidence level the hypothesis that 235U ν¯e are solely responsible for spectrum discrepancies between model and data obtained at commercial reactor cores. A data-model deviation in PROSPECT similar to that observed by commercial core experiments is preferred with respect to no observed deviation, at a 2.2σ confidence level.
In models of affect and cognition, it is held that positive affect broadens the scope of attention. Consistent with this claim, previous research has indeed suggested that positive affect is ...associated with impaired selective attention as evidenced by increased interference of spatially distant distractors. However, several recent findings cast doubt on the reliability of this observation. In the present study, we examined whether selective attention in a visual flanker task is influenced by positive mood induction. Across three experiments, positive affect consistently failed to exert any impact on selective attention. The implications of this null-finding for theoretical models of affect and cognition are discussed.
The prevalence of age-related cognitive decline will increase due to graying of the global population. The goal of the present study was to test whether playing online cognitive training games can ...improve cognitive control (CC) in healthy older adults. Fifty-four older adults (age 60-77) played five different cognitive training games online for 30 min a day over a period of seven weeks (game group). Another group of 20 older adults (age 61-73) instead answered quiz questions about documentaries online (documentary group). Transfer was assessed by means of a cognitive test battery administered before and after the intervention. The test battery included measures of working memory updating, set shifting, response inhibition, attention, and inductive reasoning. Compared with the documentary group, the game group showed larger improvement of inhibition (Stop-Signal task) and inductive reasoning (Raven-SPM), whereas the documentary group showed more improvement in selective attention (UFoV-3). These effects qualify as transfer effects, because response inhibition, inductive reasoning and selective attention were not targeted by the interventions. However, because seven other indicators of CC did not show benefits of game training and some of those that did suffered from potential baseline differences, the study as a whole provides only modest support for the potential of videogame training to improve CC in healthy older adults.
A growing number of studies suggest that EEG theta/beta ratio (TBR) is inversely related to executive cognitive control. Neurofeedback training aimed at reducing TBR (TBR NFT) might provide a tool to ...study causality in this relation and might enhance human performance. To investigate whether TBR NFT reduces TBR in healthy participants. Twelve healthy female participants were assigned (single blind) to one of three groups. Groups differed on baseline durations and one group received only sham NFT. TBR NFT consisted of eight or fourteen 25-min sessions. No evidence was found that TBR NFT had any effect on TBR. The current TBR NFT protocol is possibly ineffective. This is in line with a previous study with a different protocol.
This literature review covers the choices to consider in training complex procedural, perceptual and motor skills. In particular, we focus on laparoscopic surgery. An overview is provided of ...important training factors modulating the acquisition, durability, transfer, and efficiency of trained skills. We summarize empirical studies and their theoretical background on the topic of training complex cognitive and motor skills that are pertinent to proficiency in laparoscopic surgery. The overview pertains to surgical simulation training for laparoscopy, but also to training in other demanding procedural and dexterous tasks, such as aviation, managing complex systems and sports. Evidence-based recommendations are provided for facilitating efficiency in laparoscopic motor skill training such as session spacing, adaptive training, task variability, part-task training, mental imagery and deliberate practice.
► Conflict and reward may have opponent effects on attentional focus. ► This study: possible neural mechanism via ACC modulation? ► Behavioral effect: reward valence counteracts conflict-driven ...adaptation in a flanker task. ► EEG effect: modulation of fronto-central theta power. ► ERP effect: modulation of visual distracter-related processing.
Recent findings suggest that, relative to negative feedback, positive feedback counteracts conflict processing and subsequent attentional adaptation. Here we hypothesize that this interaction may direct adjustments in perception and action via the anterior cingulate cortex (ACC). We recorded EEG while participants performed an arrow flanker task with monetary gain or loss as arbitrary reward feedback between trials. As predicted, we found a reduction in conflict-driven adaptation for trials in which conflict was followed by monetary gain (vs. monetary loss), a behavioral effect accompanied by a modulation in early visual processing related to the processing of the distracters. Moreover, time-frequency analyses showed that ongoing fronto-central theta oscillations induced by previous conflict sustained longer after loss than after gain, an interaction presumably reflecting ACC modulation. These data provide a first important step toward understanding the neural mechanism underlying the affective regulation of conflict-driven behavior.
The late positive potential (LPP) is an event-related potential (ERP) component over visual cortical areas that is modulated by the emotional intensity of a stimulus. However, the functional ...significance of this neural modulation remains elusive. We conducted two experiments in which we studied the relation between LPP amplitude, subsequent perceptual sensitivity to a non-emotional stimulus (Experiment 1) and visual cortical excitability, as reflected by P1/N1 components evoked by this stimulus (Experiment 2). During the LPP modulation elicited by unpleasant stimuli, perceptual sensitivity was not affected. In contrast, we found some evidence for a decreased N1 amplitude during the LPP modulation, a decreased P1 amplitude on trials with a relatively large LPP, and consistent negative (but non-significant) across-subject correlations between the magnitudes of the LPP modulation and corresponding changes in d-prime or P1/N1 amplitude. The results provide preliminary evidence that the LPP reflects a global inhibition of activity in visual cortex, resulting in the selective survival of activity associated with the processing of the emotional stimulus.
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