Bonobos (Pan paniscus) show an attentional bias toward conspecifics' emotions.

In social animals, the fast detection of group members' emotional expressions promotes swift and adequate responses, which is crucial for the maintenance of social bonds and ultimately for group survival. The dot-probe task is a well-established paradigm in psychology, measuring emotional attention through reaction times. Humans tend to be biased toward emotional images, especially when the emotion is of a threatening nature. Bonobos have rich, social emotional lives and are known for their soft and friendly character. In the present study, we investigated (i) whether bonobos, similar to humans, have an attentional bias toward emotional scenes compared with conspecifics showing a neutral expression, and (ii) which emotional behaviors attract their attention the most. As predicted, results consistently showed that bonobos' attention was biased toward the location of the emotional versus neutral scene. Interestingly, their attention was grabbed most by images showing conspecifics such as sexual behavior, yawning, or grooming, and not as much-as is often observed in humans-by signs of distress or aggression. The results suggest that protective and affiliative behaviors are pivotal in bonobo society and therefore attract immediate attention in this species.

Mighty metaphors: behavioral and ERP evidence that power shifts attention on a vertical dimension.

Thinking about the abstract concept power may automatically activate the spatial up-down image schema (powerful up; powerless down) and consequently direct spatial attention to the image schema-congruent location. Participants indicated whether a word represented a powerful or powerless person (e.g. 'king' or 'servant'). Following each decision, they identified a target at the top or bottom of the visual field. In Experiment 1 participants identified the target faster when their spatial position was congruent with the perceived power of the preceding word than when it was incongruent. In Experiment 2 ERPs showed a higher N1 amplitude for congruent spatial positions. These results support the view that attention is driven to the image schema congruent location of a power word. Thus, power is partially understood in terms of vertical space, which demonstrates that abstract concepts are grounded in sensory-motor processing.

Caffeine improves anticipatory processes in task switching.

We studied the effects of moderate amounts of caffeine on task switching and task maintenance using mixed-task (AABB) blocks, in which participants alternated predictably between two tasks, and single-task (AAAA, BBBB) blocks. Switch costs refer to longer reaction times (RT) on task switch trials (e.g. AB) compared to task-repeat trials (e.g. BB); mixing costs refer to longer RTs in task-repeat trials compared to single-task trials. In a double-blind, within-subjects experiment, two caffeine doses (3 and 5mg/kg body weight) and a placebo were administered to 18 coffee drinkers. Both caffeine doses reduced switch costs compared to placebo. Event-related brain potentials revealed a negative deflection developing within the preparatory interval, which was larger for switch than for repeat trials. Caffeine increased this switch-related difference. These results suggest that coffee consumption improves task-switching performance by enhancing anticipatory processing such as task set updating, presumably through the neurochemical effects of caffeine on the dopamine system.

Anger fosters action. Fast responses in a motor task involving approach movements toward angry faces and bodies.

Efficiently responding to others' emotions, especially threatening expressions such as anger and fear, can have great survival value. Previous research has shown that humans have a bias toward threatening stimuli. Most of these studies focused on facial expressions, yet emotions are expressed by the whole body, and not just by the face. Body language contains a direct action component, and activates action preparation areas in the brain more than facial expressions. Hence, biases toward threat may be larger following threatening bodily expressions as compared to facial expressions. The current study investigated reaction times of movements directed toward emotional bodies and faces. For this purpose, a new task was developed where participants were standing in front of a computer screen on which angry, fearful, and neutral faces and bodies were presented which they had to touch as quickly as possible. Results show that participants responded faster to angry than to neutral stimuli, regardless of the source (face or body). No significant difference was observed between fearful and neutral stimuli, demonstrating that the threat bias was not related to the negativity of the stimulus, but likely to the directness of the threat in relation to the observer. Whereas fearful stimuli might signal an environmental threat that requires further exploration before action, angry expressions signal a direct threat to the observer, asking for immediate action. This study provides a novel and implicit method to directly test the speed of actions toward emotions from the whole body.

Error awareness and salience processing in the oddball task: shared neural mechanisms.

A body of work suggests similarities in the way we become aware of an error and process motivationally salient events. Yet, evidence for a shared neural mechanism has not been provided. A within subject investigation of the brain regions involved in error awareness and salience processing has not been reported. While the neural response to motivationally salient events is classically studied during target detection after longer target-to-target intervals in an oddball task and engages a widespread insula-thalamo-cortical brain network, error awareness has recently been linked to, most prominently, anterior insula cortex. Here we explore whether the anterior insula activation for error awareness is related to salience processing, by testing for activation overlap in subjects undergoing two different task settings. Using a within subjects design, we show activation overlap in six major brain areas during aware errors in an antisaccade task and during target detection after longer target-to-target intervals in an oddball task: anterior insula, anterior cingulate, supplementary motor area, thalamus, brainstem, and parietal lobe. Within subject analyses shows that the insula is engaged in both error awareness and the processing of salience, and that the anterior insula is more involved in both processes than the posterior insula. The results of a fine-grained spatial pattern overlap analysis between active clusters in the same subjects indicates that even if the anterior insula is activated for both error awareness and salience processing, the two types of processes might tend to activate non-identical neural ensembles on a finer-grained spatial level. Together, these outcomes suggest a similar functional phenomenon in the two different task settings. Error awareness and salience processing share a functional anatomy, with a tendency toward subregional dorsal and ventral specialization within the anterior insula.

Observed and self-experienced conflict induce similar behavioral and neural adaptation.

In adapting our behavior to a rapidly changing environment, we also tune our behavior to that of others. To investigate the neural bases of such adaptive mechanisms, we examined how individuals adjust their actions after decision-conflicts observed in others compared to self-experienced conflicts. Participants responded to the color of a stimulus, while its spatial position elicited either a conflicting or a congruent action. Participants were required either to respond to stimuli themselves or to observe the response of another participant. We studied the difference between interference effects following conflicting or congruent stimuli, an effect known as conflict adaptation. Consistent with earlier reports, we found that the implementation of reactive control, following congruent trials, was accompanied by activation of the right inferior frontal cortex. Individual differences in the efficacy of response inhibition covaried with the level of activation in that region. Sustaining proactive control, following incongruent trials, activated the left lateral prefrontal cortex. Most importantly, adaptive controls induced by decision-conflicts observed in others, as well as the associated prefrontal activations, were comparable to those induced by self-experienced conflicts. We show that in both behavioral and neural terms we adapt to conflicts happening to others just as if they happened to us.

More than meets the eye: age differences in the capture and suppression of oculomotor action.

Salient visual stimuli capture attention and trigger an eye-movement toward its location reflexively, regardless of an observer's intentions. Here we aim to investigate the effect of aging (1) on the extent to which salient yet task-irrelevant stimuli capture saccades, and (2) on the ability to selectively suppress such oculomotor responses. Young and older adults were asked to direct their eyes to a target appearing in a stimulus array. Analysis of overall performance shows that saccades to the target object were disrupted by the appearance of a task-irrelevant abrupt-onset distractor when the location of this distractor did not coincide with that of the target object. Conditional capture function analyses revealed that, compared to young adults, older adults were more susceptible to oculomotor capture, and exhibited deficient selective suppression of the responses captured by task-irrelevant distractors. These effects were uncorrelated, suggesting two independent sources off age-related decline. Thus, with advancing age, salient visual distractors become more distracting; in part because they trigger reflexive eye-movements more potently; in part because of failing top-down control over such reflexes. The fact that these process-specific age effects remained concealed in overall oculomotor performance analyses emphasizes the utility of looking beyond the surface; indeed, there may be more than meets the eye.

Remedial effects of motivational incentive on declining cognitive control in healthy aging and Parkinson's disease.

The prospect of reward may provide a motivational incentive for optimizing goal-directed behavior. Animal work demonstrates that reward-processing networks and oculomotor-control networks in the brain are connected through the dorsal striatum, and that reward anticipation can improve oculomotor control via this nexus. Due perhaps to deterioration in dopaminergic striatal circuitry, goal-directed oculomotor control is subject to decline in healthy seniors, and even more in individuals with Parkinson's disease (PD). Here we examine whether healthy seniors and PD patients are able to utilize reward prospects to improve their impaired antisaccade performance. Results confirmed that oculomotor control declined in PD patients compared to healthy seniors, and in healthy seniors compared to young adults. However, the motivational incentive of reward expectation resulted in benefits in antisaccade performance in all groups alike. These findings speak against structural and non-modifiable decline in cognitive control functions, and emphasize the remedial potential of motivational incentive mechanisms in healthy as well as pathological aging.

Contextual modulation of oculomotor control reflected in N2 and saccade reaction time distributions.

Avoiding reflexive saccades triggered by salient yet task-irrelevant stimuli requires the engagement of control processes that inhibit attention toward irrelevant objects and prevent reflex-like oculomotor action. In the current study participants made saccades to visual targets to the left and right of fixation as directed by target appearance. A distractor could either be presented in the same (congruent trials) or the opposite hemifield (incongruent trials) as the target. Trial context was manipulated, creating risky (mostly incongruent blocks), safe (mostly congruent blocks), or neutral conditions. Electroencephalogram was measured to examine if any contextual modulations would be reflected in the N2 peak frequently associated with performance monitoring. The results are discussed within the framework of dual mechanisms of cognitive control and suggest that a high-risk context facilitates avoidance of capture, lessening the need for reactive control.

To P(E) or not to P(E): a P3-like ERP component reflecting the processing of response errors.

ERP studies have highlighted several electrocortical components that can be observed when people make errors. We propose that the P(E) reflects processes functionally similar to those reflected in the P3 and that the P(E) and P3 should covary. We speculate that these processes refer to the motivational significance of rare target stimuli in case of the P3 and of salient performance errors in case of the P(E). Here we investigated whether P(E) amplitude after errors in a Simon task is correlated specifically to varying target-target intervals in a visual oddball task, a factor known to parametrically affect P3 amplitude. The amplitude of the P(E), but not the N(E), was observed to covary with the effect of target-target interval on P3 amplitude. The specificity of this novel finding supports the notion that the P(E) and P3 reflect similar neurocognitive processes as possibly involved in the conscious processing of motivationally significant events.

The limits of top-down control of visual attention.

The extent to which spatial selection is driven by the goals of the observer and by the properties of the environment is one of the major issues in the field of visual attention. Here we review recent experimental evidence from behavioral and eye movement studies suggesting that top-down control has temporal and spatial limits. More specifically, we argue that the first feedforward sweep of information is bottom-up, and that top-down control can influence selection only after the sweep is completed. In addition, top-down control can limit spatial selection through adjusting the size of attentional window, an area of visual space which receives priority in information sampling. Finally, we discuss the evidence found using brain imaging techniques for top-down control in an attempt to reconcile it with behavioral findings. We conclude by discussing theoretical implications of these results for the current models of visual selection.

Your conflict matters to me! Behavioral and neural manifestations of control adjustment after self-experienced and observed decision-conflict.

In everyday life we tune our behavior to a rapidly changing environment as well as to the behavior of others. The behavioral and neural underpinnings of such adaptive mechanisms are the focus of the present study. In a social version of a prototypical interference task we investigated whether trial-to-trial adjustments are comparable when experiencing conflicting action tendencies ourselves, or simulate such conflicts when observing another player performing the task. Using behavioral and neural measures by means of event-related brain potentials we showed that both own as well as observed conflict result in comparable trial-to-trial adjustments. These adjustments are found in the efficiency of behavioral adjustments, and in the amplitude of an event-related potential in the N2 time window. In sum, in both behavioral and neural terms, we adapt to conflicts happening to others just as if they happened to ourselves.

Response inhibition in motor and oculomotor conflict tasks: different mechanisms, different dynamics?

Previous research has shown that the appearance of task-irrelevant abrupt onsets influences saccadic eye movements during visual search and may slow down manual reactions to target stimuli. Analysis of reaction time distributions in the present study offers evidence suggesting that top-down inhibition processes actively suppress oculomotor or motor responses elicited by a salient distractor, in order to resolve the conflict that arises when reflex-like and deliberate responses are in opposition. Twenty-six participants carried out a variation of the oculomotor capture task. They were instructed to respond with either a saccade toward or with a button press at the side of the hemifield in which a target color singleton appeared. A distractor stimulus could appear either in the same or in the opposite hemifield. Delta plots revealed competition between reflex-like and deliberate response activation, and highlighted selective inhibition of automatic responses: While participants generally responded more slowly in incongruent compared to congruent situations, this effect diminished and even reversed in the slowest speed quantiles. These effects were present in both the oculomotor and motor response-mode conditions.