A Curvilinear Effect of Mental Workload on Mental Effort and Behavioral Adaptability: An Approach With the Pre-Ejection Period.

Objective: We tested Hancock and Szalma's mental workload model, which has never been experimentally validated at a global level with the measure of the pre-ejection period (PEP), an index of beta-adrenergic sympathetic impact.

Background: Operators adapt to mental workload. When mental workload level increases, behavioral and physiological adaptability intensifies to reduce the decline in performance.

Evidence of impaired proactive control under positive affect.

If it can be assumed that positive affect modulates cognitive control, the underlying mechanisms remain unclear. The main aim of this study was to investigate how positive affect influences proactive and reactive modes of control and to explore the temporal dynamic of this influence, in terms of its transient and/or sustained effects. We used the AX-continuous performance task, combined with event-related potentials (ERP) recording.

Individual Differences in Reward Sensitivity Modulate the Distinctive Effects of Conscious and Unconscious Rewards on Executive Performance.

Executive control can be driven by conscious and unconscious monetary cues. This has raised the exciting question regarding the role of conscious and unconscious reward in the regulation of executive control. Similarities and differences have been uncovered between unconscious and conscious processing of monetary rewards.

Differentiating Motivational from Affective Influence of Performance-contingent Reward on Cognitive Control: The Wanting Component Enhances Both Proactive and Reactive Control.

Positive affect strongly modulates goal-directed behaviors and cognitive control mechanisms. It often results from the presence of a pleasant stimulus in the environment, whether that stimulus appears unpredictably or as a consequence of a particular behavior. The influence of positive affect linked to a random pleasant stimulus differs from the influence of positive affect resulting from performance-contingent pleasant stimuli.

Disruption of information processing in schizophrenia: The time perspective.

We review studies suggesting time disorders on both automatic and subjective levels in patients with schizophrenia. Patients have difficulty explicitly discriminating between simultaneous and asynchronous events, and ordering events in time. We discuss the relationship between these difficulties and impairments on a more elementary level.

Influence of positive subliminal and supraliminal affective cues on goal pursuit in schizophrenia.

Goal pursuit is known to be impaired in schizophrenia, but nothing much is known in these patients about unconscious affective processes underlying goal pursuit. Evidence suggests that in healthy individuals positive subliminal cues are taken as a signal that goal pursuit is easy and therefore reduce the effort that is mobilized for goal attainment. Patients with schizophrenia and healthy controls were instructed that a long run of successive correct responses in a visual attention task would entitle them to a reward (the goal to attain).

Patients with schizophrenia selectively impaired in temporal order judgments.

The ability to order events in time plays a pervasive role in cognitive functions, but has only rarely been explored in patients with schizophrenia. Results we obtained recently suggested that patients have difficulties following events over time. However, this impairment concerned implicit responses at very short asynchronies, and it is not known whether it generalizes to subjective temporal order judgments.

Combined visual and motor disorganization in patients with schizophrenia.

Cognitive impairments are difficult to relate to clinical symptoms in schizophrenia, partly due to insufficient knowledge on how cognitive impairments interact with one another. Here, we devised a new sequential pointing task requiring both visual organization and motor sequencing. Six circles were presented simultaneously on a touch screen around a fixation point.

Brain Metabolic Dysfunction in Capgras Delusion During Alzheimer's Disease: A Positron Emission Tomography Study.

Capgras delusion is characterized by the misidentification of people and by the delusional belief that the misidentified persons have been replaced by impostors, generally perceived as persecutors. Since little is known regarding the neural correlates of Capgras syndrome, the cerebral metabolic pattern of a patient with probable Alzheimer's disease (AD) and Capgras syndrome was compared with those of 24-healthy elderly participants and 26 patients with AD without delusional syndrome. Comparing the healthy group with the AD group, the patient with AD had significant hypometabolism in frontal and posterior midline structures.

Patients with schizophrenia do not preserve automatic grouping when mentally re-grouping figures: shedding light on an ignored difficulty.

Looking at a pair of objects is easy when automatic grouping mechanisms bind these objects together, but visual exploration can also be more flexible. It is possible to mentally "re-group" two objects that are not only separate but belong to different pairs of objects. "Re-grouping" is in conflict with automatic grouping, since it entails a separation of each item from the set it belongs to.

Long-lasting effects of performance-contingent unconscious and conscious reward incentives during cued task-switching.

Motivation is often thought to interact consciously with executive control, although recent studies have indicated that motivation can also be unconscious. To date, however, the effects of unconscious motivation on high-order executive control functions have not been explored. Only a few studies using subliminal stimuli (i.

Personality modulation of (un)conscious processing: Novelty Seeking and performance following supraliminal and subliminal reward cues.

This study provides evidence that personality traits associated with responsiveness to conscious reward cues also influence responsiveness to unconscious reward cues. Participants with low and high levels of Novelty Seeking (NS) performed updating tasks in which they could either gain 1 euro or 5 cents. Gains were presented either supraliminally or subliminally at the beginning of each trial.

Long-lasting effect of subliminal processes on cardiovascular responses and performance.

Students were exposed to a priming task in which subliminal representations of the goal of studying were directly paired (priming-positive group) or not (priming group) to positive words. A control group without subliminal prime of the goal was added. Just after the priming task, students performed an easy or a difficult learning task based on their coursework.

Conscious and unconscious reward cues can affect a critical component of executive control.

The present study investigates whether updating an important function of executive control can be driven by unconscious reward cues. Participants had to memorize several numbers and update those numbers independently according to a sequence of arithmetic operations. At the beginning of each trial, a reward (1 euro or 5 cents) was presented, either subliminally or supraliminally.

Does motor interference arise from mirror system activation? The effect of prior visuo-motor practice on automatic imitation.

Action perception may involve a mirror-matching system, such that observed actions are mapped onto the observer's own motor representations. The strength of such mirror system activation should depend on an individual's experience with the observed action. The motor interference effect, where an observed action interferes with a concurrently executed incongruent action, is thought to arise from mirror system activation.

Motor contagion: goal-directed actions are more contagious than non-goal-directed actions.

Recent theories posit a mirror-matching system mapping observed actions onto one's own motor system. Determining whether this system makes a distinction between goal-directed and non-goal-directed actions is crucial for the understanding of its function. The present study tested whether motor interference between observed and executed actions, which is thought to be an index of perceptual-motor matching, depends on the presence of goals in the observed action.

How does achievement motivation influence mental effort mobilization? Physiological evidence of deteriorative effects of negative affects on the level of engagement.

We tested whether the effect of achievement motivation on effort is modulated by two possible factors of the motivational intensity theory (Wright and Kirby, 2001): perceived difficulty and maximally justified effort. Approach-driven (N=16) and avoidance-driven (N=16) participants were first instructed to perform a reaction time task to the best of their abilities. Next, the participants were instructed to consistently beat their performance standard established in the first condition.

The interactive effect of achievement motivation and task difficulty on mental effort.

The interactive effect of achievement motivation and task difficulty on invested mental effort, postulated by Humphreys and Revelle [Humphreys, M.S., Revelle, W.

The effects of achievement motivation, task difficulty, and goal difficulty on physiological, behavioral, and subjective effort.

The purpose of the study was to present experimental arguments evaluating the Humphreys and Revelle's model of effort. Two important factors were tested: achievement motivation and difficulty. Heart rate, heart rate variability, blood pressure, facial electromyographic reactivity, and reaction time were measured as an index of effort expenditure.