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The ability to interact with a constantly changing environment requires a balance between maintaining the currently relevant working memory content and being sensitive to potentially relevant new information that should be given priority access to working memory. Mesocortical dopamine projections to frontal brain areas modulate working memory maintenance and flexibility. Recent neurocognitive and neurocomputational work suggests that dopamine release is transiently enhanced by induced positive affect. This ERP study investigated the role of positive affect in different aspects of information processing: in proactive control (context maintenance and updating), reactive control (flexible adaptation to incoming task-relevant information), and evaluative control in an AX-CPT task. Subjects responded to a target probe if it was preceded by a specific cue. Induced positive affect influenced the reactive and evaluative components of control (indexed by the N2 elicited by the target and by the error-related negativity elicited after incorrect responses, respectively), whereas cue-induced proactive preparation and maintenance processes remained largely unaffected (as reflected in the P3b and the contingent negative variation components of the ERP).

Traditionally, dual-task interference has been attributed to the consequences of task load exceeding capacity limitations. However, the current study demonstrates that in addition to task load, the mutual compatibility of the concurrent processes modulates whether 2 tasks can be performed in parallel. In 2 psychological refractory period experiments, task load and process compatibility were independently varied. In Experiment 1, participants performed 2 mental rotation tasks. Task load (rotation angle) and between-task compatibility in rotation direction were varied. Results suggest more considerable parallel execution of compatible than of incompatible operations, arguing for the need to attribute dual-task interference not only to structural but also to functional capacity limitations. Experiment 2 tested whether functional capacity limitations to dual-task performance can be caused only by demanding processes or whether they are also induced by relatively automatic processes. Results indicate that an irrelevant circular movement of Stimulus 2 interfered more with mental rotation of Stimulus 1 if the rotation directions were opposite than if they were equal. In conclusion, compatibility of concurrent processes constitutes an indispensable element in explaining dual-task performance. (Contains 4 tables and 7 figures.)

Compared 5-, 8-, and 11-year-olds and young adults on 6 speeded performance tasks, 4 requiring an inhibition of response activation. Analyzed reaction and inhibition times; found support for hypothesis of generalized developmental changes in response activation, but revealed less pronounced development of inhibition. Concluded that a nonselective mechanism of response inhibition seems to be fully developed during early childhood. (Author/KB)

Traditionally, dual-task interference has been attributed to the consequences of task load exceeding capacity limitations. However, the current study demonstrates that in addition to task load, the mutual compatibility of the concurrent processes modulates whether 2 tasks can be performed in parallel. In 2 psychological refractory period experiments, task load and process compatibility were independently varied. In Experiment 1, participants performed 2 mental rotation tasks. Task load (rotation angle) and between-task compatibility in rotation direction were varied. Results suggest more considerable parallel execution of compatible than of incompatible operations, arguing for the need to attribute dual-task interference not only to structural but also to functional capacity limitations. Experiment 2 tested whether functional capacity limitations to dual-task performance can be caused only by demanding processes or whether they are also induced by relatively automatic processes. Results indicate that an irrelevant circular movement of Stimulus 2 interfered more with mental rotation of Stimulus 1 if the rotation directions were opposite than if they were equal. In conclusion, compatibility of concurrent processes constitutes an indispensable element in explaining dual-task performance. Keywords: PRP paradigm, dual-task performance, working memory, processing limitations

A frequency analysis was used to tag cortical activity from imagined rhythmic movements. Participants synchronized overt and imagined taps with brief visual stimuli presented at a constant rate, alternating between left and right index fingers. Brain potentials were recorded from across the scalp and topographic maps made of their power at the alternation frequency between left and right taps. Two prominent power foci occurred in each hemisphere for both overt and imagined taps, one over sensorimotor cortex and the other over posterior parietal cortex, with homologous foci in opposite hemispheres arising from oscillations 180[degrees] out of phase. These findings demonstrate temporal isomorphism at a neural level between overt and imagined movements and illustrate a new approach to studying covert actions. Keywords: covert motor processes, motor imagery, synchronization tapping, movement-related brain potentials, frequency tagging

This study investigated the role of arousal and effort costs in the cognitive benefits of alternating between sitting and standing postures using a sit‐stand desk, while measuring executive functions, self‐reports, physiology, and neural activity in a 2‐h laboratory session aimed to induce mental fatigue. Two sessions were conducted with a one‐week gap, during which participants alternated between sitting and standing postures each 20‐min block in one session and remained seated in the other. In each block, inhibition, switching, and updating were assessed. We examined effects of time‐on‐task, acute (local) effects of standing versus sitting posture, and cumulative (global) effects of a standing posture that generalize to the subsequent block in which participants sit. Results (N = 43) confirmed that time‐on‐task increased mental fatigue and decreased arousal. Standing (versus sitting) led to acute increases in arousal levels, including self‐reports, alpha oscillations, and cardiac responses. Standing also decreased physiological and perceived effort costs. Standing enhanced processing speed in the flanker task, attributable to shortened nondecision time and speeded evidence accumulation processes. No significant effects were observed on higher‐level executive functions. Alternating postures also increased heart rate variability cumulatively over time. Exploratory mediation analyses indicated that the positive impact of acute posture on enhanced drift rate was mediated by self‐reported arousal, whereas decreased nondecision time was mediated by reductions in alpha power. In conclusion, alternating between sitting and standing postures can enhance arousal, decrease effort costs, and improve specific cognitive and physiological outcomes. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Mood has been shown to influence cognitive performance. However, little is known about the influence of mood on sensory processing, specifically in the auditory domain. With the current study, we sought to investigate how auditory processing of neutral sounds is affected by the mood state of the listener. This was tested in two experiments by measuring masked-auditory detection thresholds before and after a standard moodinduction procedure. In the first experiment (N = 76), mood was induced by imagining a mood-appropriate event combined with listening to mood inducing music. In the second experiment (N = 80), imagining was combined with affective picture viewing to exclude any possibility of confounding the results by acoustic properties of the music. In both experiments, the thresholds were determined by means of an adaptive staircase tracking method in a two-interval forced-choice task. Masked detection thresholds were compared between participants in four different moods (calm, happy, sad, and anxious), which enabled differentiation of mood effects along the dimensions arousal and pleasure. Results of the two experiments were analyzed both in separate analyses and in a combined analysis. The first experiment showed that, while there was no impact of pleasure level on the masked threshold, lower arousal was associated with lower threshold (higher masked sensitivity). However, as indicated by an interaction effect between experiment and arousal, arousal did have a different effect on the threshold in Experiment 2. Experiment 2 showed a trend of arousal in opposite direction. These results show that the effect of arousal on auditory-masked sensitivity may depend on the modality of the mood-inducing stimuli. As clear conclusions regarding the genuineness of the arousal effect on the masked threshold cannot be drawn, suggestions for further research that could clarify this issue are provided. [ABSTRACT FROM AUTHOR]

In natural languages, two negating elements that cancel each other out (as innot impossible) are logically equivalent to the non-negated word form (in this case,possible). It has been proposed that the function of sentential double negation is to create coherence between sentences containing opposing information. Thus,not impossibleis functionally different frompossible. The present ERP study tested this hypothesis in Dutch. Native speakers read sentences in which evoked negative expectations are cancelled by a second sentence including either a double negation or the corresponding non-negated word form. Results showed that non-negated word forms, such aspossible, elicited a larger N400 effect than double negations, such asnot impossible. We suggest that canceling out a negative expectation by a double negation compared to the non-negated word form, makes it easier for the reader to integrate the two sentences semantically and connect them to the present discourse. [ABSTRACT FROM PUBLISHER]

Determining the optimal design for surgical skills training is an ongoing research endeavor. In education literature, varied practice is listed as a positive intervention to improve acquisition of knowledge and motor skills. In the current study we tested the effectiveness of a varied practice intervention during laparoscopy training. Twentyfour trainees (control group) without prior experience received a 3 weeks laparoscopic skills training utilizing four basic and one advanced training task. Twenty-eight trainees (experimental group) received the same training with a random training task schedule, more frequent task switching and inverted viewing conditions on the four basic training tasks, but not the advanced task. Results showed inferior performance of the experimental group on the four basic laparoscopy tasks during training, at the end of training and at a 2 months retention session. We assume the inverted viewing conditions have led to the deterioration of learning in the experimental group because no significant differences were found between groups on the only task that had not been practiced under inverted viewing conditions; the advanced laparoscopic task. Potential moderating effects of inter-task similarity, task complexity, and trainee characteristics are discussed. [ABSTRACT FROM AUTHOR]

Rationale: The P3 is a ubiquitous component of stimulus-driven neural activity that can be observed in scalp electrophysiological recordings. Multiple lines of evidence suggest an important role for the noradrenergic system in the generation of the P3. However, pharmacological studies of the P3 using noradrenergic manipulations have so far been limited to agents that affect α2-receptor signaling. Objectives: The present study investigated whether β-adrenergic receptors are involved in the generation of the P3 and the error positivity (Pe), a component of the event-related potential that is elicited by errors and that bears many similarities to the P3. Methods: We used a double-blind, placebo-controlled, crossover design in which we examined in human participants ( N = 16) the effect of a single dose of propranolol (80 mg) on the amplitudes of the P3 observed in visual and auditory oddball tasks and the Pe observed in a flanker task. Results: We found that P3s to auditory stimuli were increased in amplitude following treatment with propranolol. Propranolol also modulated the P3 to visual stimuli, but in a direction dependent on participants' level of trait anxiety: In participants with lower trait anxiety, propranolol resulted in a (non-significant) decrease in P3 amplitudes; in participants with higher trait anxiety, propranolol significantly enhanced P3 amplitude. Propranolol did not modulate the amplitude of the Pe or behavioral measures of conflict/error-related performance adjustments. Conclusions: These results provide the first evidence for involvement of β-adrenergic receptors in P3 generation. We speculate that propranolol affected the P3 through actions at β2-receptors in the locus coeruleus. [ABSTRACT FROM AUTHOR]

Passionate love is associated with intense changes in emotion and attention which are thought to play an important role in the early stages of romantic relationship formation. Although passionate love usually involves enhanced, near-obsessive attention to the beloved, anecdotal evidence suggest that the lover's concentration for daily tasks like study and work may actually be impaired, suggesting reduced cognitive control. Affect might also contribute to changes in cognitive control. We examined the link between passionate love and cognitive control in a sample of students who had recently become involved in a romantic relationship. Intensity of passionate love as measured by the Passionate Love Scale was shown to correlate with decreased individual efficiency in cognitive control as measured in Stroop and flanker task performance. There was no evidence that affective changes mediate this effect. This study provides the first empirical evidence that passionate love in the early stages of romantic relationship is characterized by impaired cognitive control. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Negative affect in healthy populations regulates the appraisal of demanding situations, which tunes subsequent effort mobilization and adjustments in cognitive control. In the present study, we hypothesized that dysphoria in depressed individuals similarly modulates this adaptation, possibly through a neural mechanism involving serotonergic regulation. We tested the effect of dysphoria induced by acute tryptophan depletion (ATD) in remitted depressed patients on conflict adaptation in a Simon task. ATD temporarily lowers the availability of the serotonin precursor L-Tryptophan and is known to increase depressive symptoms in approximately half of remitted depressed participants. We found that depressive symptoms induced by ATD were associated with increased conflict adaptation. Our finding extends recent observations implying an important role of affect in regulating conflict-driven cognitive control. [ABSTRACT FROM AUTHOR]