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There are only a few studies on the brain networks involved in the ability to prepare in time, and most of them followed a correlational rather than a neuropsychological approach. The present neuropsychological study performed multiple regression analysis to address the relationship between both grey and white matter (measured by magnetic resonance imaging in patients with brain lesion) and different effects in temporal preparation (Temporal orienting, Foreperiod and Sequential effects). Two versions of a temporal preparation task were administered to a group of 23 patients with acquired brain injury. In one task, the cue presented (a red versus green square) to inform participants about the time of appearance (early versus late) of a target stimulus was blocked, while in the other task the cue was manipulated on a trial-by-trial basis. The duration of the cue-target time intervals (400 versus 1400 ms) was always manipulated within blocks in both tasks. Regression analysis were conducted between either the grey matter lesion size or the white matter tracts disconnection and the three temporal preparation effects separately. The main finding was that each temporal preparation effect was predicted by a different network of structures, depending on cue expectancy. Specifically, the Temporal orienting effect was related to both prefrontal and temporal brain areas. The Foreperiod effect was related to right and left prefrontal structures. Sequential effects were predicted by both parietal cortex and left subcortical structures. These findings show a clear dissociation of brain circuits involved in the different ways to prepare in time, showing for the first time the involvement of temporal areas in the Temporal orienting effect, as well as the parietal cortex in the Sequential effects. (C) 2016 Elsevier Inc. All rights reserved.

Purpose: The aim of this study was to analyze cone beam computed tomography (CBCT) densitometries of maxillary sinuses augmented with human bone allograft. In addition, previously obtained microradiographic specimens were used to verify the diagnostic potential of CBCT. Materials and Methods: A two-stage protocol was conducted in 21 consecutive patients, all with a crestal bone height < 2 mm. Mineralized human bone allograft particles were used to augment sinuses using a lateral window approach. A succession of CBCT scans of the maxilla were taken before surgery, immediately after sinus augmentation, and 6, 10, and 18 months after implant placement. Using virtual probes, CBCT images taken at 6, 8, and 10 mm from the crestal surface were processed with medical imaging software and expressed as gray level (GL). Results: A total of 24 sinus augmentation procedures were performed in 21 patients. The average values of CBCT-GL ranged from 571 to 654, presenting the maximum value at 8 mm immediately after implant placement and the minimum value at 6 mm after 10 months. Furthermore, it was found that the graft mineral content decreased over time, completely disappearing between 10 and 11 months. Conclusion: CBCT and the medical imaging software employed for imaging visualization are reliable tools to study biomaterial behavior after sinus augmentation procedures. In addition, results from this study demonstrate that a complete resorption of human bone allograft is possible. Due to the limited sample size, further clinical and morphometric studies are needed.

Driving is a task mainly reliant on the visual system. Most of the time, while driving, our eyes are constantly focusing and refocusing between the road and the dashboard or near and far traffic. Thus, prolonged driving time should produce visual fatigue. Here, for the first time, we investigated the effects of driving time, a common inducer of driver fatigue, on two ocular parameters: the accommodative response (AR) and the intraocular pressure (IOP). A pre/post-test design has been used to assess the impact of driving time on both indices. Twelve participants (out of 17 recruited) completed the study (5 women, 24.42±2.84years old). The participants were healthy and active drivers with no visual impairment or pathology. They drove for 2h in a virtual driving environment. We assessed AR and IOP before and after the driving session, and also collected subjective measures of arousal and fatigue. We found that IOP and AR decreased (i.e., the accommodative lag increased) after the driving session (p=0.03 and p

There is substantial evidence of bias in the processing of emotion in people with complicated grief (CG). Previous studies have tended to assess the expression of emotion in CG, but other aspects of emotion (mainly emotion recognition, and the subjective aspects of emotion) have not been addressed, despite their importance for practicing clinicians. A quasi-experimental design with two matched groups (Complicated Grief, N = 24 and Non-Complicated Grief, N = 20) was carried out. The Facial Expression of Emotion Test (emotion recognition), a set of pictures from the International Affective Picture System (subjective experience of emotion) and the Symptom Checklist 90 Revised (psychopathology) were employed. The CG group showed lower scores on the dimension of valence for specific conditions on the IAPS, related to the subjective experience of emotion. In addition, they presented higher values of psychopathology. In contrast, statistically significant results were not found for the recognition of emotion. In conclusion, from a neuropsychological point of view, the subjective aspects of emotion and psychopathology seem central in explaining the experience of those with CG. These results are clinically significant for psychotherapists and psychoanalysts working in the field of grief and loss.

The main aim of this research was to investigate the decision making process in risky situations. We studied how different types of feedback on risky driving behaviors modulate risk evaluation and risk-taking. For a set of risky traffic situations, participants had to make evaluative judgments (judge the situation as risky or not) and urgent decisions (brake or not). In Experiment 1, participants received feedback with and without negative emotional content when they made risky behaviors. In Experiment 2 we investigated the independent effects of feedback and negative emotional stimuli. The results showed three important findings: First, urgent decisions were faster [F(1, 92) = 6.76, p = .01] and more cautious [F(1, 92) = 17.16, p < .001] than evaluative judgments. These results suggest that evaluative judgments of risk and actual risk-taking may not always coincide, and that they seem to be controlled by two different processing systems as proposed by dual process theories. Second, feedback made participants’ responses even faster [F(1, 111) = 71.53, p < .001], allowing greater risk sensitivity [F(1, 111) = 22.12, p < .001] and skewing towards more cautious responses [F(1, 111) = 14.09, p < .001]. Finally, emotional stimuli had an effect only when they were presented as feedback. The results of this research increase our understanding of the processes involved in risky driving behavior and suggest efficient ways to control risk taking through the use of feedback.

Emotional interference on behavior is commonly observed when task-irrelevant negative stimuli appear before behavioral targets. One explanation postulates that affect-laden stimuli readily capture attention, interfering with the processing of the upcoming target. Emotional stimuli might also preactivate motor programs incompatible with the demanded response. Using a cued go/no-go procedure we showed that task-irrelevant unpleasant stimuli cause interference or facilitation depending on their onset asynchrony relative to the target. We observed interference with short (200 ms) stimulus-target asynchronies and facilitation for longer ones (600 ms), both for key press (Experiment 1) and key release (Experiment 2) responses. The interference effect is compatible with an attentional explanation, but the behavioral facilitation is hard to accommodate within either attentional or motor accounts. This interference-facilitation pattern can be explained assuming that once the attentional effect subsides, emotional processing may enhance the perceptual processing of the stimuli, or lower the decision threshold, thereby facilitating the response selection process.

Background Impulsivity is thought to play a key role in cocaine addiction onset and progression; therefore, we hypothesized that different facets of impulsive personality may be significantly associated with brain structural abnormalities in cocaine-dependent individuals. Methods Thirty-eight cocaine-dependent individuals and 38 non-drug using controls completed the UPPS-P scale (measuring five different facets of impulsivity: sensation seeking, lack of premeditation, lack of perseverance, and positive and negative urgency) and were scanned on a 3T MRI scanner. We used whole-brain voxel-based morphometry analyses (VBM) to detect differences in gray matter (GM) and white matter (WM) volumes between cocaine users and controls, and to measure differences in the way that impulsivity relates to GM and WM volumes in cocaine users vs. controls. Results Cocaine-dependent individuals had lower GM volumes in a number of sections of the orbitofrontal cortex, right inferior frontal gyrus, right insula, left amygdala and parahippocampal gyrus, temporal gyrus, and bilateral caudate. They also had lower WM volumes in the left inferior and medial frontal gyrus, superior temporal gyrus, right anterior cingulate cortex, insula and caudate. There was a positive correlation between trait impulsivity and GM volume in the left inferior/middle frontal gyrus of cocaine-dependent individuals, a pattern directly opposed to the association in controls. Conversely, in cocaine users lack of premeditation was negatively correlated with GM volume in the insula and the putamen. Conclusions Trait impulsivity may influence cocaine dependence by impacting its neurobiological underpinnings in frontostriatal systems.

La emocion constituye un elemento fundamental en el estudio del comportamiento de conduccion. En la actualidad desde el ambito de la psicologia y la neuro-economia se suele diferenciar dos posibles formas de modulacion emocional del comportamiento. Por un lado, la emocion es comunmente definida como una reaccion subjetiva al ambiente acompanada de una serie de cambios fisiologicos, cognitivos y conductuales que pueden modificar nuestro comportamiento. Pero existe otro tipo de modulacion emocional mas sutil, asociada al proceso de toma de decisiones, la cual no tiene por que conllevar cambios conscientes en el organismo y, sin embargo, tambien orientaria el comportamiento del conductor. En Psicologia del Trafico, la distincion entre estos dos tipos de modulacion emocional no ha recibido toda la atencion necesaria. En este trabajo se analiza la necesidad de estudiar ambas concepciones emocionales desde puntos de vista diferenciados, para asi alcanzar una mejor comprension del comportamiento de los conductores, y poder incluir estos factores emocionales en el diseno de programas de evaluacion y prevencion de riesgos.

Resumen Objetivo: Existe un amplio consenso sobre la existencia de una mayor incidencia de accidentes de trafico en personas con sindrome de apneas-hipopneas del sueno (SAHS). Sin embargo, algunos aspectos de esta relacion estan aun por dilucidar. No se ha podido demostrar cual es la causa probable de esta mayor accidentalidad, existen posibles factores de confusion no controlados y algunos instrumentos de evaluacion utilizados poseen una baja validez ecologica. El objetivo del estudio fue analizar la conducta de riesgo en conduccion de pacientes con SAHS en un entorno vial virtual realista y con trafico simulado. Material y metodos: Se evaluo la conducta de riesgo en la conduccion mediante el simulador Honda Riding Trainer, en 12 pacientes diagnosticados de SAHS, tratados con presion positiva continua (CPAP), y 12 controles emparejados. Tambien se evaluaron, a traves de cuestionarios, la somnolencia diurna en los dos grupos y la fatiga mental y los niveles de activacion durante la prueba. Resultados: Aunque los pacientes con SAHS mostraban una mayor somnolencia diurna, no se han mostrado mas arriesgados que los controles durante la conduccion. No hubo diferencias en fatiga mental o niveles de activacion durante la simulacion. Conclusiones: A diferencia de los resultados encontrados en los estudios clasicos, cuando la evaluacion se realiza con herramientas mas ecologicas y la duracion de las pruebas es mas breve, la ejecucion de los pacientes con SAHS tratados con CPAP no difiere de la de los controles. Estos hallazgos apoyan el uso de la CPAP y respaldan la inclusion de pruebas de simulacion virtuales para obtener o prorrogar el permiso o licencia de conducir, sobre todo, en poblaciones de riesgo.

In the last five decades, cognitive scientists and the psychologists of reasoning have dedicated a lot of effort designing usable traffic signs. This study investigated the interference effect produced by the position of the sign elements in traffic signage on response accuracy and reaction time. Sixteen drivers performed a flanker interference reaction time task. Incongruent graphical/space solutions, actually used for the airport stack-type sign, lead to increased reaction time and a reduction in the proportion of correct answers. These results suggest that incongruent visual information should be avoided, as this might impair drivers' performance. These findings provide important information for the specification of future signage design guidelines and for improving road safety.

Developing a valid measurement of mental fatigue remains a big challenge and would be beneficial for various application areas, such as the improvement of road traffic safety. In the present study we examined influences of mental fatigue on the dynamics of saccadic eye movements. Based on previous findings, we propose that among amplitude and duration of saccades, the peak velocity of saccadic eye movements is particularly sensitive to changes in mental fatigue. Ten participants completed a fixation task before and after 2 h of driving in a virtual simulation environment as well as after a rest break of fifteen minutes. Driving and rest break were assumed to directly influence the level of mental fatigue and were evaluated using subjective ratings and eye movement indices. According to the subjective ratings, mental fatigue was highest after driving but decreased after the rest break. The peak velocity of saccadic eye movements decreased after driving while the duration of saccades increased, but no effects of the rest break were observed in the saccade parameters. We conclude that saccadic eye movement parameters—particularly the peak velocity—are sensitive indicators for mental fatigue. According to these findings, the peak velocity analysis represents a valid on-line measure for the detection of mental fatigue, providing the basis for the development of new vigilance screening tools to prevent accidents in several application domains.

In road safety literature the effects of emotional content and salience of advertising billboards have been scarcely investigated. The main aim of this work was to uncover how affect-laden roadside advertisements can affect attention – eye-movements – and subsequent risky decisions – braking – on the Honda Riding Trainer motorcycle simulator. Results indicated that the number of fixations and total fixation time elicited by the negative and positive emotional advertisements were larger than the neutral ones. At the same time, negative pictures got later gaze disengagement than positive and neutral ones. This attentional capture results in less eye fixation times on the road relevant region, where the important driving events happen. Finally, the negative emotional valence advertisements sped up braking on subsequent risky situations. Overall results demonstrated how advertisements with emotional content modulate attention allocation and driving decisions in risky situations and might be helpful for designing roadside advertisements regulations and risk prevention programs.

Motorcyclist deaths and injuries follow the trend in sales rather than in growth in the number of motorcycles, suggesting that fatalities are related to the lack of driver experience with recently purchased motorcycles. The aim of the present investigation was to assess the effects of experience and training in hazard perception. We compared first-time riders (people who are not yet riders/drivers) before and after training in six different riding scenarios to expert motorcycle riders. Thirty-three participants took part in the experiment. Volunteers rode a moped in a fixed-base virtual environment and were presented with a number of preset risky events. We used a multidimensional methodology, including behavioral, subjective and eye-movements data. The results revealed differences between experts and first-time riders, as well as the effect of training on the novice group. As expected, training led to an improvement in the riding skills of first-time riders, reducing the number of accidents, improving their capacity to adapt their speed to the situation, reducing trajectory-corrective movements, and changing their pattern of gaze exploration. We identified several behavioral and eye-related measures that are sensitive to both long-term experience and training in motorcycle riders. These findings will be useful for the design of on-line monitoring systems to evaluate changes in risk behavior and of programs for preventing and controlling risk behavior and improving situation awareness for novice riders, with the ultimate aim of reducing road-user mortality.

Recent development of systems for assisted driving has raised questions about what features of the stimuli perceived by a driver may improve driving behaviour and road safety. The present study aimed to uncover whether emotional auditory stimuli can affect risky behaviour in hazardous situations. Forty-nine volunteers rode a motorcycle in a virtual environment and went through a number of preset risky scenarios, some of which were cued by a sound (a beep, a positive emotional sound or a negative sound). Results showed that hearing the beep reduced the frequency of accidents in the upcoming risky situation, while the emotional cues did not. Likewise, the beep induced the drivers to decrease their speed and focus their gaze on relevant areas of the visual field, while the emotional sounds did not. These results suggest that auditory warning systems for vehicles should avoid using emotion-laden sounds, as their affective content might diminish their utility to increase driving alertness. These findings could provide important information for the development of new advanced driver assistance systems and in general for the specification of future Human-Machine-Interaction design guidelines.

INTRODUCTION For research and applications in the field of (neuro)ergonomics, it is of increasing importance to have reliable methods for measuring mental workload. In the present study we examined the hypothesis that saccadic eye movements can be used for an online assessment of mental workload. METHODS Saccadic main sequence (amplitude, duration and peak velocity) was used as a diagnostic measure of mental workload in a virtual driving task with three complexity levels. We tested 18 drivers in the SIRCA driving simulator while their eye movements were recorded. The Wickens' multiple resources model was used as theoretical framework. Changes in mental workload between the complexity levels were evaluated multidimensionally, using subjective rating, performance in a secondary task, and other behavioral indices. RESULTS Saccadic peak velocity decreased (7.2 visual degrees/s) as the mental workload increased, as measured by scores of mental workload test (15.2 scores) and the increase of the reaction time on the secondary task (46 ms). DISCUSSION Saccadic peak velocity is affected by variations in mental workload during ecologically valid tasks. We conclude that saccadic peak velocity could be a useful diagnostic index for the assessment of operators' mental workload and attentional state in hazardous environments.

We present a model aimed at accounting for learning of predictive and causal relationships involving stimulus compounds, by means of a mechanism based on a normative-methodological analysis of causality that goes beyond the traditional associative/rule-based controversy. According to the model, causal learning is attained by computing the validity of each stimulus in a given learning situation. The situation is determined by the assumptions, objectives, and aims held by the learner or demanded by the learning context. Hence, validity computation depends on task demands: causal, predictive, or diagnostic according to a general principle of normative contextualization that allows learners to adapt a between-cues competition principle in a flexible way. Validity is computed using the Relevance Relativization mechanism, a linear model, based on the balance between the probability of stimulus combinations and the probability of each cue. Thus, cue interactions occur mainly when the combination of stimuli shows predictive changes in relation to the same cues considered individually. This model makes novel predictions concerning variations of the competition principle as a function of the type of procedure, including blocking, simultaneous blocking, and relative validity. In addition, our model also integrates top-down and bottom-up processing levels, including individuals' assumptions or previous beliefs.

We present data from an ongoing research project on the cognitive, emotional and neuropsychological basis of risk behaviour. The main aim of the project is to build a model of risk behaviour so that if we know certain cognitive, behavioural and emotional variables, we will be able to predict decisions made in the face of uncertainty and risk, with the final goal of designing programs for evaluating, preventing and controlling risk behaviour. The objective of the present study was to look for individual differences in hazard perception during a static riding simulation and their relationship with mental workload. We used a multidimensional methodology, including behavioural, subjective and physiological data. The behavioural measures were obtained in a static riding simulation during eight hazard situations. We evaluated whether eye activity measures correlated with cognitive workload and different types of risky behaviours. Eye movement parameters were measured using a video-based eye tracking system. We found that risk-prone individuals showed specific patterns of risky behaviours and that peak of saccadic velocity and subjective mental workload indexes were both reliable indicators of risk proneness. Mental workload was higher for participants showing attitudes to risk behaviours probably because of a lack of conscious awareness of specific cues indicating dangerous scenarios.

In two experiments, we investigated the relative impact of causal beliefs and empirical evidence on both decision making and causal judgments, and whether this relative impact could be altered by previous experience. Participants had to decide which of two alternatives would attain a higher outcome on the basis of four cues. After completing the decision task, they were asked to estimate to what extent each cue was a reliable cause of the outcome. Participants were provided with instructions that causally related two of the cues to the outcome, whereas they received neutral information about the other two cues. Two of the four cues—a causal and a neutral cue—had high validity and were both generative. The remaining two cues had low validity, and were generative in Experiment 1, but almost not related to the outcome in Experiment 2. Selected groups of participants in both experiments received pre-training with either causal or neutral cues, or no pre-training was provided. Results revealed that the impact of causal beliefs and empirical evidence depends on both the experienced pre-training and cue validity. When all cues were generative and participants received pre-training with causal cues, they mostly relied on their causal beliefs, whereas they relied on empirical evidence when they received pre-training with neutral cues. In contrast, when some of the cues were almost not related to the outcome, participants’ responses were primarily influenced by validity and—to a lesser extent—by causal beliefs. In either case, however, the influence of causal beliefs was higher in causal judgments than in decision making. While current theoretical approaches in causal learning focus either on the effect of causal beliefs or empirical evidence, the present research shows that both factors are required to explain the flexibility involved in human inferences.

Masked priming experiments are frequently used to study automatic aspects of word processing. Direct measures of such processing obtained with functional neuroimaging techniques (ERPs, fMRI, etc.) need to isolate the neural activation related to relevant events when they are rapidly followed by others (a situation found in other popular paradigms such as the attentional blink and repetition blindness). Here we examine the assumption of "simple insertion", which underlies the use of subtraction to isolate components of temporally overlapping waveforms. We propose two novel linear methods and illustrate how they extract temporal and spatial ERP components that the subtraction method fails to detect. We show this through the analysis of ERP data from a masked semantic priming procedure. The new techniques reveal activation generated by unconscious (masked) prime words as early as 100 ms and 200 ms post stimulus-onset; a pattern which simple subtraction fails to detect.

The present study is aimed at identifying how prior causal beliefs and covariation information contribute to belief updating when evidence, either compatible or contradictory with those beliefs, is provided. Participants were presented with a cover story with which it was intended to activate or generate a causal belief. Variables related to the prior belief (the type of information, the strength of the cause–effect causal link, and how confident the participant was that the link existed) were assessed. Subsequently, participants were presented with covariational information and were asked to update their beliefs in light of the new evidence. Information reliability, prior belief’s causal influence magnitude, and the cause–effect level of contingency portrayed by the new information – but not the type of the prior belief – are shown to directly determine belief updating.

The main aim of this work was to look for cognitive biases in human inference of causal relationships in order to emphasize the psychological processes that modulate causal learning. From the effect of the judgment frequency, this work presents subsequent research on cue competition (overshadowing, blocking, and super-conditioning effects) showing that the strength of prior beliefs and new evidence based upon covariation computation contributes additively to predict causal judgments, whereas the balance between the reliability of both, beliefs and covariation knowledge, modulates their relative weight. New findings also showed “inattentional blindness” for negative or preventative causal relationships but not for positive or generative ones, due to failure in codifying and retrieving the necessary information for its computation. Overall results unveil the need of three hierarchical levels of a whole architecture for human causal learning: the lower one, responsible for codifying the events during the task; the second one, computing the retrieved information; finally, the higher level, integrating this evidence with previous causal knowledge. In summary, whereas current theoretical frameworks on causal inference and decision-making usually focused either on causal beliefs or covariation information, the present work shows how both are required to be able to explain the complexity and flexibility involved in human causal learning.

At the present time, peri-implantitis has become a global burden that occurs with a frequency from 1% to 47% at implant level. Therefore, we aimed herein at assessing the impact of peri-implant maintenance therapy (PIMT) on the prevention of peri-implant diseases. Electronic and manual literature searches were conducted by 3 independent reviewers using several databases, including MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and Cochrane Oral Health Group Trials Register, for articles up to June 2015 without language restriction. Articles were included if they were clinical trials aimed at demonstrating the incidence of peri-implant diseases under a strict regime or not of PIMT. Implant survival and failure rate were studied as secondary outcomes. A meta-analysis was conducted to evaluate the influence of PIMT and other reported variables upon peri-implant diseases. Thirteen and 10 clinical trials were included in the qualitative and quantitative analysis, respectively. Mucositis was affected by history of periodontitis and mean PIMT at implant and patient levels, respectively. Similarly, significant effects of history of periodontal disease were obtained for peri-implantitis for both implant and patient levels. Furthermore, mean PIMT interval was demonstrated to influence the incidence of peri-implantitis at implant but not patient level. PIMT interval showed significance at both levels. For implant survival, implants under PIMT have 0.958 the incident event than those with no PIMT. Within the limitations of the present systematic review, it can be concluded that implant therapy must not be limited to the placement and restoration of dental implants but to the implementation of PIMT to potentially prevent biologic complications and hence to heighten the long-term success rate. Although it must be tailored to a patient’s risk profiling, our findings suggest reason to claim a minimum recall PIMT interval of 5 to 6 mo. Additionally, it must be stressed that even in the establishment of PIMT, biologic complications might occur. Thus, patient-, clinical-, and implant-related factors must be thoroughly explored.

The new and recent advances in neuroelectric and neuroimaging technologies provide a new era for further exploring and understanding how brain and cognition function can be stimulated by environmental factors, such as exercise, and particularly to study whether physical exercise influences brain development in early ages. The present study, namely the ActiveBrains project, aims to examine the effects of a physical exercise programme on brain and cognition, as well as on selected physical and mental health outcomes in overweight/obese children. A total of 100 participants aged 8 to 11 years are randomized into an exercise group (N=50) or a control group (N=50). The intervention lasts 20-weeks, with 3-5 sessions per week of 90 min each, and is mainly focused on high-intensity aerobic exercise yet also includes muscle-strengthening exercises. The extent to what the intervention effect remains 8-months after the exercise programme finishes is also studied in a subsample. Brain structure and function and cognitive performance are assessed using structural and functional magnetic resonance imaging and electroencephalographic recordings. Secondary outcomes include physical health outcomes (e.g. physical fitness, body fatness, bone mass and lipid-metabolic factors) and mental health outcomes (e.g. chronic stress indicators and overall behavioural and personality measurements such as anxiety or depression). This project will substantially contribute to the existing knowledge and will have an impact on societies, since early stimulation of brain development might have long lasting consequences on cognitive performance, academic achievement and in the prevention of behavioural problems and the promotion of psychological adjustment and mental health. Clinical trials. Gov identifier: NCT02295072.

Aircrew fatigue is a major contributor to operational errors in civil and military aviation. Objective detection of pilot fatigue is thus critical to prevent aviation catastrophes. Previous work has linked fatigue to changes in oculomotor dynamics, but few studies have studied this relationship in critical safety environments. Here we measured the eye movements of US Marine Corps combat helicopter pilots before and after simulated flight missions of different durations.We found a decrease in saccadic velocities after long simulated flights compared to short simulated flights. These results suggest that saccadic velocity could serve as a biomarker of aviator fatigue.

Background: During fetal and perinatal periods, many nutrients, such as long-chain polyunsaturated fatty acids [contained in fish oil (FO)] and folate, are important in achieving normal brain development. Several studies have shown the benefits of early nutrition on children’s neurocognitive development. However, the evidence with regard to the attention system is scarce. Objectives: The aim of this study was to analyze the long-term effects of FO, 5-methyltetrahydrofolate (5-MTHF), or FO+5-MTHF prenatal supplementation on attention networks. Design: Participants were 136 children born to mothers from the NUHEAL (Nutraceuticals for a Healthy Life) project (randomly assigned to receive FO and/or 5-MTHF or placebo prenatal supplementation) who were recalled for a new examination 8.5 y later. The response conflict-resolution ability (using congruent and incongruent conditions)), alerting, and spatial orienting of attention were evaluated with behavioral measures (Attention Network Test), electroencephalography/event-related potentials (ERPs), and standardized low-resolution brain electromagnetic tomography (sLORETA). Results: Children born to mothers supplemented with 5-MTHF alone solved the response conflict more quickly than did the placebo and the FO+5-MTHF groups (all P < 0.05). Differences between ERP amplitudes for the conflict conditions were also observed. sLORETA analysis showed higher activation of the right midcingulate cortex for the incongruent condition. In addition, a significant slowing down of response speed depending on the warning cue in the 5-MTHF and FO groups was observed. Conclusions: Folate supplementation during pregnancy, rather than FO or FO+5-MTHF supplementation, improves children’s ability to solve response conflicts. This advantage seems to be based on the higher activation of the midcingulate cortex, indicating that early nutrition influences the functionality of specific brain areas involved in executive functions. This trial was registered at clinicaltrials.gov as NCT01180933.

Purpose Sinus floor elevation via the lateral window approach represents a reliable technique for augmenting bone volume in the atrophic posterior maxilla. However, controversy remains regarding the effect of placement of a barrier membrane over the lateral window. This histomorphometric meta-analysis sought to clarify the effect of barrier membranes in lateral window sinus augmentation. Materials and methods An electronic search of three databases and a hand search in implant-related journals for studies published through January 2013 in the English language was conducted. Randomized controlled trials, prospective human clinical studies, retrospective investigations, and case series reporting histomorphometric results after sinus elevation using the lateral window approach with at least six patients and a minimum follow-up period of 6 months were included. Results The initial search yielded 1,040 articles, of which 94 were further evaluated for eligibility. Finally, 37 studies were chosen and separated into membrane (group 1) and no-membrane (group 2) groups. Similar vital bone formation was found in both groups: 32.36% for group 1 and 33.07% for group 2. Conclusion Based does not influence the amount of vital bone formation after sinus augmentation. Additionally, the type of grafting material used and healing time did not influence the histomorphometric outcome.

The present study focuses on the effect of selective attention on causal learning. Three effects of the level of attention to predictive symptoms in positive and negative contingency learning tasks are reported. First, participants accurately detected a positive relationship between an incidental cue and a contingent outcome, although judgements were slightly lower than those for the attended cue. Second, participants were unable to detect negative relationships between incidental cues and outcomes, which suggests a major role of selective attention in this type of learning. Third, participants retrieved the frequency of each trial type more accurately in the attended conditions than in the incidental conditions. These findings show how attention guides and constrains human causal learning and reveal an inattentional blindness effect for negative contingency learning.

A priming procedure was used to study the processing of distractors located either inside (between the location of two targets) or outside (peripherally to the locations of the targets) the focus of attention. The stimuli were five-letter arrays, and participants had to decide whether two marked target letters were the same or different. In Experiments 1 and 2, positive priming was obtained both when targets and in-distractors in primes repeated as targets in probes; negative priming was found when out-distractor primes repeated as targets in probes. In Experiment 3, we also manipulated the match in letter case from primes to probes. In-distractors produced reliable positive priming, irrespective of whether the letters matched in case. In contrast out-distractors produced negative priming but only when the letters had the same case in primes and probes. These results are attributed to a spatial attention process operating (in this case) on low-level visual features, and an object-based selection process t...

A classical definition of automaticity establishes that automatic processing occurs without attention or consciousness, and cannot be controlled. Previous studies have demonstrated that semantic priming can be reduced if attention is directed to a low-level of analysis. This finding suggests that semantic processing is not automatic since it can be controlled. In this paper, we present two experiments that demonstrate that semantic processing may occur in the absence of attention and consciousness. A negative semantic priming effect was found when a low-level prime-task was required and when a masked lexical decision prime-task was performed (Experiment 1). This paper also discusses the limitations of the inhibitory mechanism involved in negative semantic priming effect.

Semantic (positive) priming refers to the facilitated processing of a probe word when preceded by a related prime word, and is a widely used technique for investigating semantic activation. However, the effect is interrupted or eliminated when attention is directed to low-level features of the prime word, such as its letters, a result which has been used to question the automaticity of semantic processing. We investigated this issue using both behavioural [reaction time (RT)] and electrophysiological measures [event-related potentials (ERPs)]. Subjects performed semantic categorization (living vs. nonliving) and letter search ("A" or "E") tasks on prime words followed by lexical decision on the probe. RT results showed the expected elimination of semantic priming following letter search. However, both prime tasks were affected by the semantic category of the prime, indicating that the meaning was processed. The ERP results supported this conclusion: an early component previously associated with automatic semantic processing [the Recognition Potential (RP)] was sensitive to the category of the prime word irrespective of the prime task. However, a later component (N400) was significantly affected by the task, in both the prime (categorization task) and probe words (semantic priming). The results dissociate rapid, automatic semantic processing from semantic priming. We suggest that a later inhibitory control mechanism suppresses this semantic activation when it is not relevant to the task, and that this produces the loss of semantic priming.

A number of studies using trial-by-trial learning tasks have shown that judgments of covariation between a cue c and an outcome o deviate from normative metrics. Parameters based on trial-by-trial predictions were estimated from signal detection theory (SDT) in a standard causal learning task. Results showed that manipulations of P(c) when contingency (Delta P) was held constant did not affect participants' ability to predict the appearance of the outcome (d') but had a significant effect on response criterion (c) and numerical causal judgments. The association between criterion c and judgment was further demonstrated in 2 experiments in which the criterion was directly manipulated by linking payoffs to the predictive responses made by learners. In all cases, the more liberal the criterion c was, the higher judgments were. The results imply that the mechanisms underlying the elaboration of judgments and those involved in the elaboration of predictive responses are partially dissociable.

The aim of this work was to explore the nature of elementary operations (engage, move, disengage, and filtering) of spatial attention in deaf experts in sign language. Good communication skills require deaf people to rapidly change attention to at least two separate spatial locations, the facial expression and the hand signs of the speaker. Overtraining imposed by sign language demands might have modified certain characteristics of the spatial attention operations. To test that, a spatial orienting task was used in two experiments. Experiment 1 showed that deaf subjects reoriented their attention to the target location faster than hearing subjects in invalid trials. Experiment 2 indicated that inhibition of return decays faster in deaf than in hearing people. These results suggest that deaf subjects can disengage their attention faster than hearing subjects, fostering search of relevant information in more spatial locations.

This work aimed at demonstrating, first, that naive reasoners are able to infer the existence of a relationship between two events that have never been presented together and, second, the sensitivity of such inference to the causal structure of the task. In all experiments, naive participants judged the strength of the causal link between a cue A and an outcome O in a first phase and between a second cue B and the same outcome O in a second phase. In the final test, participants estimated the degree of correlation between the two cues, A and B. Participants perceived the two cues as significantly more highly correlated when they were effects of a common potential cause (Experiment 1a and 2) than when they were potential causes of a common effect (Experiment 1b and 2). This effect of causal directionality on inferred correlation points out the influence of mental models on human causal detection and learning, as proposed by recent theoretical models.

This work aimed to study the interaction between judgment frequency and a previous non-contingent experience upon the causal relationships detection and attribution in a subsequent contingent task. Experiment 1 showed an impaired detection after a non-contingent experience independently of the judgment frequency during non-contingency, revealing the reliability of this previously found effect. Experiment 2 showed firstly, a clear judgment of frequency effect upon causal attribution in the contingent phase; secondly, the results also showed that a non-contingent experience altered the influence of each type of trials upon causal attribution in the subsequent contingent task. These results raise doubts about the ability of single mechanism models, be it associative or statistical, to explain human causal attribution and learning. However, the recently proposed belief revision model was able to fully explain these results, as showed buy the simulation of this model based on the predictions and parameters derived from previous research.

Resumen En una serie de (res experimentos se estudia una posible especificidad espacial del mecanismo atencional inhibitorio. A través del paradigma de priming negativo se examina en concreto si existen diferencias entre estímulos distractores situados dentro del foco atencional del sujeto y otros situados en la periferia. Mediante la utilización de una letter-matching task similar a la que emplearon Nelly, Lissner y Beck (1990), se obtiene efecto de priming negativo sólo en aquellas letras distractores que se sitúan fuera del foco de atención del sujeto. Los resultados sugieren que el sistema inhibitorio que actúa a nivel de características físicas y espaciales no puede inhibir los estímulos situados dentro del foco, por lo cual todos ellos son forzosamente procesados a nivel semántico. Abstract In a series of three experiments it studies a possible spatial specificity of the mechanism of inhibitory attention. Across negative priming paradigm, it examines in a specific way if it exits differences between distract stimulus placed inside the area of attention of the subject and of others placed in the periphery. By means of the utilization of a letter matching task similar to that it was used by Nelly, Lissner and Beck (1990), it obtains priming negative effect only in those distract letter which place out of the area of attention of the subject. The results suggest that the inhibitory system that work in the level of physical and special characteristics can not inhibit the stimulus placed inside the area, for which all of them are forcibly process in a semamic level.

espanolEn nuestro trabajo hemos recopilarlo la evidencia experimental mas relevante existente en el campo del aprendizaje causal, con el objetivo de responder a las preguntas basicas que subyacen a un analisis computacional de la competencia causal humana. Desde las respuestas a dichas preguntas, planteamos un modelo que restringe el rango de estructuras algoritmicas viables. Las criticas al articulo en el que presentamos dicho modelo se han debido, fundamentalmente, a una asimilacion de los niveles de analisis y los niveles de representacion en la explicacion de los fenomenos psicologicos. Parte de la solucion a la controversia planteada pasa por resolver las posibles imprecisiones terminologicas y conceptuales cometidas. Por tanto, en esta replica hemos realizado, en primer lugar, un esfuerzo adicional por establecer una terminologia que facilite una verdadera comunicacion entre los especialistas del area. Y, en segundo lugar, pretendemos reforzar la conexion logica entre la evidencia presentada y el modelo propuesto. Dicho modelo, entendido como un modelo no excluyente de otras posturas teoricas, surge como una necesidad impuesta por los datos, y con el pretendemos, ya no defender una vision teorica opuesta a la de los autores situados en el paradigma tradicional de aprendizaje, sino integrar dicho paradigma en un marco explicativo mas amplio. Palabras clave: Causalidad, niveles de analisis, induccion, teorias generales. EnglishIn our previous work, we have compiled the most relevant experimental evidence from the different fields related to causal learning and causal induction, in order to answer the basic questions that underlie a computational analysis of human causal competence. Taking into account such answers, we postulate a model that constraints the range of viable algorithmic structures. Most criticisms to this integrative model have been due to an erroneous identification of analysis levels and representational levels in the explanation of behavior. From our point of view, this terminological and conceptual puzzlement is a general feature of the theoretical debate in the field. Hence, we will try to show how the main controversies can be partially solved by establishing a common terminology that allows a better communication among theorists. And secondly, we will try to strengthen the logical connection between the different sources of available data and the model we propose here. A meaningful integration of those data imposes several restrictions upon the algorithmic structure that computes causal relations. Therefore, with our account, we do not intend to exclude any approach, but to integrate the traditional learning paradigms into a broader explanatory framework

En las dos ultimas decadas el estudio del Aprendizaje Causal ha experimentado un gran avance en lo que se refiere a la formulacion de modelos que tratan de explicar como las personas somos capaces de inferir relaciones e causalidad a partir de !a observacion de la relacion estadistica entre acontecimientos del medio. Muchos modelos reducen la explicacion a un algoritmo de computo simple. Frente a esa idea mecanicista, en este trabajo adoptamos una perspectiva computacional, intentando dotar de sentido normativo y funcional a la adquisicion de conocimiento causal. En otras palabras, pretendemos responder a dos preguntas fundamentales: a) que informacion es relevante en el aprendizaje de relaciones de causalidad?, y b) ? por lue dacha informacion es rele-vante? Desde este punto de vista, lo mas importante no es describir la formulacion matematica de los procesos implicados en el procesamiento, sino analizar el sentido funcional de dichos procesos. A continuacion, discutire-mos sobre como este marco computacional puede guiar la construccion teorica en el futuro a nivel algoritmico y ayudar a integrar los distintos modelos actuales. Palabras clave: Aprendizaje de causalidad, razonamiento inductivo, contingencia, correlacion.

Cardiovascular disease has been associated with 40% of deaths in high-income countries and 28% in lower-income countries. The relationship between periodontitis and acute myocardial infarction is well documented, but it has not been established whether the extent and severity of periodontitis influence the infarct size. This cross-sectional and analytic study was designed to investigate the association of chronic periodontitis extent and severity with acute myocardial infarct size as indicated by serum cardiac troponin I and myoglobin levels. Sociodemographic, periodontal, cardiologic, and hematologic variables were gathered in 112 consecutive patients with myocardial infarction. The extent (Arbes Index) and severity (Periodontal Inflammatory Severity Index) of the chronic periodontitis were significantly associated with troponin I levels after controlling for sociodemographic and clinical confounders (change in R2 = .041, p < .02, and R2 = .031, p = .04). However, only the extent index accounted for levels of myoglobin (change in R2 = .030, p < .05), total leukocytes (change in R2 = .041 p < .02), and neutrophils (change in R2 = .059, p < .01). Mediated regression analysis showed that leukocytes and neutrophils may underlie these observed relationships of chronic periodontitis with troponin I and myoglobin. To our knowledge, this study contributes the first research data demonstrating that the extent and severity of periodontitis is positively associated with acute myocardial infarct size as measured by serum troponin I and myoglobin levels.

Most research connecting task performance and neural activity to date has been conducted in laboratory conditions. Thus, field studies remain scarce, especially in extreme conditions such as during real flights. Here, we investigated the effects of flight procedures of varied complexity on the in-flight EEG activity of military helicopter pilots. Flight procedural complexity modulated the EEG power spectrum: highly demanding procedures (i.e., takeoff and landing) were associated with higher EEG power in the higher frequency bands, whereas less demanding procedures (i.e., flight exercises) were associated with lower EEG power over the same frequency bands. These results suggest that EEG recordings may help to evaluate an operator's cognitive performance in challenging real-life scenarios, and thus could aid in the prevention of catastrophic events.

Hypoxia, defined as decreased availability of oxygen in the body's tissues, can lead to dyspnea, rapid pulse, syncope, visual dysfunction, mental disturbances such as delirium or euphoria, and even death. It is considered to be one of the most serious hazards during flight. Thus, early and objective detection of the physiological effects of hypoxia is critical to prevent catastrophes in civil and military aviation. The few studies that have addressed the effects of hypoxia on objective oculomotor metrics have had inconsistent results, however. Thus, the question of whether hypoxia modulates eye movement behavior remains open. Here we examined the effects of short-term hypobaric hypoxia on the velocity of saccadic eye movements and intersaccadic drift of Spanish Air Force pilots and flight engineers, compared with a control group that did not experience hypoxia. Saccadic velocity decreased with time-on-duty in both groups, in correlation with subjective fatigue. Intersaccadic drift velocity increased in the hypoxia group only, suggesting that acute hypoxia diminishes eye stability, independently of fatigue. Our results suggest that intersaccadic drift velocity could serve as a biomarker of acute hypoxia. These findings may also contribute to our understanding of the relationship between hypoxia episodes and central nervous system impairments.

In this study, we analyzed the influence of prosthetic abutment height on marginal bone loss (MBL) around implants in the posterior maxilla. In this retrospective cohort study, the radiographically determined MBL was related to the height of the abutments of internal conical connection implants at 6 and 18 months post-loading. Data were gathered on age, sex, bone substratum, smoking habit, history of periodontitis, and prosthetic features, among other variables. A linear mixed model was used for statistical analysis. The study included 131 patients receiving 315 implants. MBL rates at 6 and 18 months were mainly affected by the abutment height but were also significantly influenced by the bone substratum, periodontitis, and smoking habit. MBL rates were higher for prosthetic abutment < 2 mm vs. ≥ 2 mm, for periodontal vs. non-periodontal patients, for grafted vs. pristine bone, and for a heavier smoking habit. The abutment height is a key factor in MBL. MBL rates followed a non-linear trend, with a greater MBL rate during the first 6 months post-loading than during the next 12 months.

Objective. This study was designed to explore relationships of resonance frequency analysis (RFA)—assessed implant stability (ISQ values) with bone morphometric parameters and bone quality in an ex vivo model of dental implants placed in human femoral heads and to evaluate the usefulness of this model for dental implant studies. Material and Methods. This ex vivo study included femoral heads from 17 patients undergoing surgery for femoral neck fracture due to osteoporosis (OP) ( ) or for total prosthesis joint replacement due to severe hip osteoarthrosis (OA) ( ). Sixty mm Dentsply Astra implants were placed, followed by RFA. CD44 immunohistochemical analysis for osteocytes was also carried out. Results. As expected, the analysis yielded significant effects of femoral head type (OA versus OA) ( ), but not of the implants ( ) or of the interaction of the two factors ( ). Bonferroni post hoc comparisons showed a lower mean ISQ for implants in decalcified ( ) heads than in fresh ( ) or fixated ( ) heads (both ). The ISQ score (fresh) was significantly higher for those in OA ( ) versus OP ( ) heads. However, mixed linear analysis showed no significant association between ISQ scores and morphologic or histomorphometric results ( in all cases), and no significant differences in ISQ values were found as a function of the length or area of the cortical layer (both ). Conclusion. Although RFA-determined ISQ values are not correlated with morphometric parameters, they can discriminate bone quality (OP versus OA). This ex vivo model is useful for dental implant studies., This investigation was partially supported by Research Group no. CTS-138 (Junta de Andalucía, Spain).

Injury to pedestrians is a major safety hazard in many countries. Since the beginning of the last century, modern cities have been designed around the use of motor vehicles despite the unfavourable interactions between the vehicles and pedestrians. This push towards urbanization resulted in a substantial number of crashes and fatalities involving pedestrians every day, all over the world. Thus, improving the design of urban cities and townships is a pressing issue for modern society. The study presented here provides a characterization of pedestrian safety problems, with the emphasis on signalized crosswalks (i.e. traffic signal) design solutions. We tested the impact of seven different traffic light configurations (steady [green, yellow, and red], flashing [green, yellow, and red], and light off) on pedestrian self-reported road-crossing behavior, using a 11-point scale -ranging from 0 (“I never cross in this situation”) to 10 (“I always cross in this situation”). Results showed that mandatory solutions (steady green vs. steady red) are the best solutions to avoid unsafe pedestrian behaviors while crossing controlled intersections (frequency of crossing: Mgreen = 9.4 ± 1 vs. Mred = 2.6 ± 2). These findings offer important guidelines for the design of future traffic signals for encouraging a pedestrian/transit-friendly environment.

Research on the contribution of positive personality traits to the progression of coronary heart disease (CHD) is notably absent. Resilience is the capacity to develop oneself successfully despite adverse circumstances. In a study of patients with acute coronary syndrome (ACS), the authors investigated the effect of resilience on indicators of CV severity and the physiological mechanisms underlying this effect. Patients (n = 134) completed a scale measuring resilience. The authors measured troponin-I and myoglobin as indicators of ACS severity, and white blood cell (WBC) count and neutrophils as inflammatory markers. Results showed that self-efficacy-a component of resilience-was negatively related to both myoglobin and troponin after the acute coronary event. The relationship between resilience and these prognostic markers was mediated by the WBC count. Importantly, this result held significant after controlling for the effect of classic CV risk factors and demographics. The authors conclude that resilience decreases the extent of the myocardial infarction by affecting the inflammatory response, showing a protective effect., En la actualidad la investigación sobre la influencia de los rasgos de personalidad positivos sobre la enfermedad coronaria (EC) es escasa. La resiliencia se define como la capacidad para autodesarrollarse con éxito a pesar de las circunstancias adversas. En un estudio, los autores han investigado el efecto de la resiliencia en varios indicadores de severidad en pacientes con síndrome coronario agudo (SCA; n=134) y los mecanismos que subyacen a este efecto. Los pacientes completaron una escala que medían sus niveles de resiliencia. Los autores midieron los niveles de troponina-I y mioglobina como indicadores de la severidad del SCA, y el número total de glóbulos blancos (NGB) y neutrófilos como marcadores de inflamación. Los resultados han puesto de manifiesto que el nivel de auto-eficacia –un componente de la resiliencia– se relaciona negativamente con los niveles de mioglobina y troponina después de un evento coronario agudo. La relación entre la resiliencia y estos marcadores está mediada por el NGB. Este resultado se mantiene tras controlar el efecto de los factores cardiovasculares clásicos y demográficos. Los autores concluyen que la resiliencia reduce la extensión del infarto de miocardio influyendo en la respuesta inflamatoria, mostrando un efecto protector., Open Access funded by Asociación Española de Psicología Conductual, This research was supported by grants PSI2011-22954, to R. García-Retamero and PSI2012-39292 to Andrés Catena.

The automaticity of the semantic processing of words has been questioned because of the reduction of semantic priming when the prime word is processed nonsemantically--for example, in letter search (the prime task effect). In two experiments, prime distractor words produced semantic priming in a subsequent lexical decision task, but with the direction of priming (positive or negative) depending on the prime task. Lexico-semantic tasks produced negative semantic priming, whereas letter search produced positive semantic priming. These results are discussed in terms of task-based inhibition. We argue that, given the results from the distractors, the absence of semantic priming does not indicate an absence of semantic activation but reflects the action of control processes on prepotent responses when less practiced responses are needed.

A noncontingent experience affects the subsequent detection of positive and negative contingencies between the same events. Experiments 1 and 2 showed that such preexposure can produce both an impairment in the detection of subsequent positive contingency and a facilitation of a negative one, independent of the level of contingency during the contingent phase. Experiment 3 raised difficulties for a model that assumes that associations to the context can explain this asymmetrical effect. Experiment 4 suggested that the different weights usually assigned to the different types of trials when computing the contingency between events can change as a result of a noncontingent experience with the same events. This change supports an account of the asymmetrical effect by a belief revision model based on a mechanism that updates the weights of the different trial types as a function of previous experience. More generally, the belief revision model is a statistical (i.e., nonassociative) model of learning that is capable of accounting for trial-order effects, which have long posed problems for statistical models.