Disgust-specific modulation of early attention processes

Although threatening images are known to attract and keep our attention, little is known about the existence of emotion-specific attention effects. In this study (N = 46), characteristics of an anticipated, disgust-specific effect were investigated by means of a covert orienting paradigm incorporating pictures that were either disgust-evoking, fear-evoking, happiness-evoking or neutral. Attention adhesion to these pictures was measured by the time necessary to identify a peripheral target, presented 100, 200, 500, or 800 ms after picture onset. Main results showed that reaction times were delayed for targets following the disgust-evoking pictures by 100 and 200 ms, suggesting that only these pictures temporarily grabbed hold of participants' attention. These delays were similar for ignore- and attend-instructions, and they were not affected by the participants' anxiety levels or disgust sensitivity. The disgust-specific influence on early attention processes thus appeared very robust, occurring in the majority of participants and without contribution of voluntary- and strategic-attention processes. In contrast, a smaller and less reliable effect of all emotional (arousing) pictures was present in the form of delayed responding in the 100 ms cue-target interval. This effect was more transitory and apparent only in participants with relatively high state-anxiety scores. Practical and theoretical consequences of these findings are discussed.     

Emotional modulation of attention affects time perception: Evidence from event-related potentials

Emotional effects on human time perception are generally attributed to arousal speeding up or slowing down the internal clock. The aim of the present study is to investigate the less frequently considered role of attention as an alternative mediator of these effects with the help of event-related potentials (ERPs). Participants produced short intervals (0.9, 1.5, 2.7, and 3.3 s) while viewing high arousal images with pleasant and unpleasant contents in comparison to neutral images. Behavioral results revealed that durations were overproduced for the 0.9 s interval whereas, for 2.7 and 3.3 s intervals, underproduction was observed. The effect of affective valence was present for the shorter durations and decreased as the target intervals became longer. More specifically, the durations for unpleasant images were less overproduced in the 0.9 s intervals, and for the 1.5 s trials, durations for unpleasant images were slightly underproduced, compared to pleasant images, which were overproduced. The analysis of different ERP components suggests possible attention processes related to the timing of affective images in addition to changes in pacemaker speed. Early Posterior Negativity (EPN) was larger for positive than for negative images, indicating valence-specific differences in activation of early attention mechanisms. Within the early P1 and the Late Positive Potential (LPP) components, both pleasant and unpleasant stimuli exhibited equal affective modulation. Contingent Negative Variation (CNV) remained independent of both timing performance and affective modulation. This pattern suggests that both pleasant and unpleasant stimuli enhanced arousal and captured attention, but the latter effect was more pronounced for pleasant stimuli. The valence-specificity of affective attention revealed by ERPs combined with behavioral timing results suggests that attention processes indeed contribute to emotion-induced temporal distortions, especially for longer target intervals.     

The automatic orienting of attention to goal-relevant stimuli

It is often assumed that attention is automatically allocated to stimuli relevant to one’s actual goals. However, the existing evidence for this idea is limited in several ways. We investigated whether words relevant to a person’s current goal influence the orienting of attention even when an intention to attend to the goal-relevant stimuli is not present. In two experiments, participants performed a modified spatial cueing paradigm combined with a second task that induced a goal. The results of the experiments showed that the induced goal led to the orientation of attention to goal-relevant words in the spatial cueing task. This effect was not found for words semantically related to the goal-relevant words. The results provide evidence for motivational accounts of attention, which state that the automatic allocation of attention is guided by the current goals of a person.     

When language gets emotional: Irony and the embodiment of affect in discourse

Although there is increasing evidence to suggest that language is grounded in perception and action, the relationship between language and emotion is less well understood. We investigate the grounding of language in emotion using a novel approach that examines the relationship between the comprehension of a written discourse and the performance of affect-related motor actions (hand movements towards and away from the body). Results indicate that positively and negatively valenced words presented in context influence motor responses (Experiment 1), whilst valenced words presented in isolation do not (Experiment 3). Furthermore, whether discourse context indicates that an utterance should be interpreted literally or ironically can influence motor responding, suggesting that the grounding of language in emotional states can be influenced by discourse-level factors (Experiment 2). In addition, the finding of affect-related motor responses to certain forms of ironic language, but not to non-ironic control sentences, suggests that phrasing a message ironically may influence the emotional response that is elicited.     

Enactment of approach and avoidance behavior influences the scope of perceptual and conceptual attention

In this study, we tested the hypothesis, derived from the theorizing of Derryberry and Tucker (1994), that the mere enactment of approach or avoidance behavior, without concomitant pursuit of personal approach or avoidance goals, can independently moderate the scope (i.e., breadth or narrowness) of attention on both the perceptual and conceptual levels. Specifically, we predicted that enactment of approach behavior would broaden attentional scope, engendering a focus upon global perceptual structure and facilitating conceptual access to mental representations with lower a priori accessibility, whereas enactment of avoidance behavior would constrict attentional scope, engendering a focus upon local perceptual details and “choking off” conceptual access to mental representations with lower a priori accessibility. These hypotheses were borne out in three experiments, using two different manipulations of approach vs. avoidance actions.     

Multiple influences of reward on perception and attention

Visual processing is influenced by stimulus-driven and goal-driven factors. Recent interest has centred on understanding how reward might provide additional contributions to visual perception and unravelling the underlying neural mechanisms. In this review, I suggest that the impact of reward on vision is not unitary and depends on the type of experimental manipulation. With this in mind, I outline a possible classification of the main paradigms employed in the literature and discuss potential brain processes that operate during some of the experimental manipulations described.     

An anxiety-induced bias in the perception of a bistable point-light walker

Human sensitivity for social cues is exquisite, as illustrated by the ease with which simplified point-light movements invoke social and emotional responses. Compared to faces, these biological motion stimuli only recently started to be used to explore questions regarding social cognition and anxiety. We presented human point-light walkers that could be perceived as facing towards or facing away from the observer, and tested whether participants with high social anxiety would perceive these bistable stimuli differently, because this type of stimuli has particular relevance for them. The results showed that observers with high social anxiety tended to see walkers as facing away more frequently than those with low social anxiety. This may mean that high socially anxious observers are biased towards the more positive perceptual alternative because they are motivated to protect themselves against threatening social experiences, but we also explore alternative explanations. The findings are in line with the evidence for a positivity bias in perception, also called wishful seeing, but in contrast with the attentional negativity bias often found in social anxiety. We discuss reasons for this divergence and possible limitations of the current study.     

Emotional modulation of attention orienting: A classical conditioning study

Emotional modulation of attention shifting was investigated in Posner's (1980) spatial orienting task by conditioning the attention cue to an aversive white noise. Prior to the attention task, the Conditioning group received a 90dB white noise unconditioned stimulus (UCS) contingent upon the frame-lit rectangle attention cue, while the Control group received non-contingent presentations. The Conditioning group evidenced greater skin conductance responses to the frame-lit rectangle in the conditioning phase, reflecting an electrodermal conditioned response. In the attention phase, the frame-lit rectangle served as the attention cue in the spatial orienting task. The Conditioning group showed equally fast reaction times (RTs) to targets presented outside the location of the cue as to targets at the same location as the cue, reflecting elimination of the cognitive cost usually involved in shifting attention. The Control group evidenced the regular cost of shifting attention away from the location of the cue. The Conditioning group also evidenced a larger N1-component with a parietal distribution of the event-related brain potentials to the cue and a larger N1-component at the frontal regions to targets presented outside the cued location. This suggests that both visual orienting to the cue and attention shifting from cue to target on invalid trials were amplified by the emotional salience attached to the cue through the classical conditioning procedure.     

Changing the focus of attention: The interacting effect of valence and arousal

We examined how valence and arousal of an image influence visual attention. “Spotlight of attention” theory suggests that positive affect broadens, and negative affect narrows, one's aperture of attention, whereas the arousal theory literature suggests that arousal level is what modulates attentional focus, with highly arousing affect capturing attention, regardless of valence. In two experiments, a digit parity task was used to index the influence of valence, and arousal, on visual attention. Positive or negative images were displayed centrally on each trial, with single digits presented more peripherally (Experiment 1) or more centrally (Experiment 2) to the image. In both Experiments participants were slower, and less accurate at making parity decisions (e.g., both digits odd or both even) when the image was negative relative to positive, and of high arousal. For low arousal images, positive, relative to negative, valence images led to greater impairment of the digit parity task. Findings suggest that arousal level of images modulates the influence of valence on distribution of visual attention. Highly negative emotional images may command or capture attention, but there are other factors that can lead to attention capture, even in low arousing positive stimuli.     

Emotional attention: effects of emotion and gaze direction on overt orienting of visual attention

In the present study we considered the two factors that have been advocated for playing a role in emotional attention: perception of gaze direction and facial expression of emotions. Participants performed an oculomotor task in which they had to make a saccade towards one of the two lateral targets, depending on the colour of the fixation dot which appeared at the centre of the computer screen. At different time intervals (stimulus onset asynchronies, SOAs: 50,100,150 ms) following the onset of the dot, a picture of a human face (gazing either to the right or to the left) was presented at the centre of the screen. The gaze direction of the face could be congruent or incongruent with respect to the location of the target, and the expression could be neutral or angry. In Experiment 1 the facial expressions were presented randomly in a single block, whereas in Experiment 2 they were shown in separate blocks. Latencies for correct saccades and percentage of errors (saccade direction errors) were considered in the analyses. Results showed that incongruent trials determined a significantly higher percentage of saccade direction errors with respect to congruent trials, thus confirming that gaze direction, even when task-irrelevant, interferes with the accuracy of the observer’s oculomotor behaviour. The angry expression was found to hold attention for a longer time with respect to the neutral one, producing delayed saccade latencies. This was particularly evident at 100 ms SOA and for incongruent trials. Emotional faces may then exert a modulatory effect on overt attention mechanisms.     

Response-repetition costs in choice-RT tasks: Biased expectancies or response inhibition?

Repetition effects are often viewed as informative regarding the cognitive mechanisms of action control. One particular finding, namely costs for repeating the same response in subsequent trials, especially challenges theorizing. Costs for response repetitions have recently been reported in task-switch studies on task-switch trials (whereas benefits usually arise in task-repetition trials), but also in some choice-RT task studies. In three experiments, two of the most successful accounts for the response-repetition costs in choice-RT task studies and task switching were tested: an expectancy-based explanation, and an inhibition-based account. Using a choice-RT task introduced by Smith (1968) and manipulating the response–stimulus interval (RSI) and the categorizability of the stimuli, some specific predictions of the two accounts were tested. The results clearly revealed that expectancy-based explanations fail to account for the observed patterns of effects, whereas they are well in line with the predictions from the inhibition-based account. Finally, the results are further discussed with respect to alternative accounts from the field of task switching.     

Emotional stimuli exert parallel effects on attention and memory

Because emotional and neutral stimuli typically differ on non-emotional dimensions, it has been difficult to determine conclusively which factors underlie the ability of emotional stimuli to enhance immediate long-term memory. Here we induced arousal by varying participants' goals, a method that removes many potential confounds between emotional and non-emotional items. Hungry and sated participants encoded food and clothing images under divided attention conditions. Sated participants attended to and recalled food and clothing images equivalently. Hungry participants performed worse on the concurrent tone-discrimination task when they viewed food relative to clothing images, suggesting enhanced attention to food images, and they recalled more food than clothing images. A follow-up regression analysis of the factors predicting memory for individual pictures revealed that food images had parallel effects on attention and memory in hungry participants, so that enhanced attention to food images did not predict their enhanced memory. We suggest that immediate long-term memory for food is enhanced in the hungry state because hunger leads to more distinctive processing of food images rendering them more accessible during retrieval.     

The locus of the emotional Stroop effect: A study with the PRP paradigm

Stimuli that are clearly positive or negative (hence valence-laden stimuli) have the potential to interrupt unrelated task processing. A typical example is the emotional Stroop effect (ESE) in which responding to a certain task feature (e.g., color) is delayed by the presentation of task-irrelevant valent stimuli (e.g., negative pictures) compared to valence-neutral stimuli. Here we scrutinize which processes are slowed down by irrelevant but valent stimulation. In Experiment 1, participants performed in a Psychological Refractory Period (PRP) experiment with tone discrimination as Task 1 and color discrimination as Task 2. Importantly, colors in Task 2 were accompanied by valent or neutral pictures. Valent pictures delayed responding in Task 2 (thus an ESE) and this delay was additive to the time interval between tasks. In Experiment 2, task order was reversed and the ESE in Task 1 fully propagated to the Task 2 tone discrimination. These results imply that irrelevant valence-laden stimulation delays capacity-limited processes, and we suggest that this is a late perceptual process acting on stimulus categorization.     

Efficiency and interactions of alerting,orienting and executive networks: The impact of imperative stimulus type

The Attention Network Test (ANT) generates measures of three attention networks: alerting, orienting and executive control. Arrows have been generally used as imperative stimuli in the different versions of this paradigm. However, it is unknown whether the directional nature of these stimuli can modulate the efficiency of the executive control and its interaction with alerting and orienting. We developed three ANT variants to examine attentional effects in response to directional and non-directional stimuli. Arrows (ANTI-A), colored fruits (ANTI-F) and black geometrical-shape (ANTI-G) were used as imperative stimuli (i.e., flanker stimuli). Data collected from fifty-two university students, in two experiments, showed that arrows stimuli produced a greater interference effect and a greater orienting effect as compared to the other stimuli. Moreover, only arrows modulated the interaction between executive control and orienting: a reduced flanker effect in spatially cued trials was only observed in ANTI-A. These results suggest that the directional value of the stimuli increases the conflict and modulates the efficiency of executive control and its interaction with orienting network.     

Processing of task-irrelevant natural scenes in social anxiety

In this study, by manipulating perceptual load, we investigated whether socially anxious people process task-irrelevant, non-emotional, natural scenes. When attention was directed to letters and perceptual load was low, task-irrelevant natural scenes were processed, as evidenced by repetition priming effects, in both high and low socially anxious people. In the high perceptual load condition, repetition-priming effects decreased in participants with low social anxiety, but not in those with high social anxiety. The results were the same when attention was directed to pictures of animals: even in the high perceptual load condition, high socially anxious participants processed task-irrelevant natural scenes, as evidenced by flanker effects. However, when attention was directed to pictures of people, task-irrelevant natural scenes were not processed by participants in either anxiety group, regardless of perceptual load. These results suggest that high socially anxious individuals could not inhibit task-irrelevant natural scenes under conditions of high perceptual load, except when attention was focused on people.     

Flexible cue combination in the guidance of attention in visual search

Hodsoll and Humphreys (2001) have assessed the relative contributions of stimulus-driven and user-driven knowledge on linearly- and nonlinearly separable searches. However, the target feature used to determine linear separability in their task (i.e., target size) was required to locate the target. In the present work, we investigated the contributions of stimulus-driven and user-driven knowledge when a linearly- or a nonlinearly-separable feature is available but not required for target identification. We asked observers to complete a series of standard color × orientation conjunction searches in which target size was either linearly- or nonlinearly separable from the size of the distractors. When guidance by color × orientation and guidance by size information are both available, observers rely on whichever information results in the best search efficiency. This is the case irrespective of whether we provide target foreknowledge by blocking stimulus conditions, suggesting that feature information is used in both a stimulus-driven and a user-driven fashion.     

The effects of visual context and individual differences on perception and evaluation of modern art and graffiti art

Traditionally, artworks are seen as autonomous objects that stand (or should stand) on their own. However, at least since the emergence of Conceptual Art in the 1920s and Pop Art in the 1960s, art lacks any distinctive perceptual features that define it as such. Art, therefore, cannot be defined without reference to its context. Some studies have shown that context affects the evaluation of artworks, and that specific contexts (street for graffiti art, museum for modern art) elicit specific effects (Gartus & Leder, 2014). However, it is yet unclear how context changes perception and appreciation processes. In our study we measured eye-movements while participants (64 psychology undergraduates, 48% women) perceived and evaluated beauty, interest, emotional valence, as well as perceived style for modern art and graffiti art embedded into either museum or street contexts. For modern art, beauty and interest ratings were higher in a museum than in a street context, but context made no difference for the ratings of graffiti art. Importantly, we also found an interaction of context and individual interest in graffiti for beauty and interest ratings, as well as for number of fixations. Analyses of eye-movements also revealed that viewing times were in general significantly longer in museum than in street contexts. We conclude that context can have an important influence on aesthetic appreciation. However, some effects depend also on the style of the artworks and the individual art interests of the viewers.     

Emotional and hemispheric asymmetries in shifts of attention: An ERP study

Inhibition of return (IOR) refers to the larger response time to cued targets appearing at long cue-to-target intervals. Given emotion–attention interactions and associated visual field (VF) asymmetries, we examined the effects of emotions and hemispheric processing on object- and location-based IOR. We expected reduced IOR and right hemispheric bias accompanied by differences in event-related potentials (ERPs) including lack of suppression of cued N1 and enhancement of Nd components for sad targets. Reaction times and ERPs were recorded in an exogenous cuing detection task using happy and sad schematic faces. Results revealed reduced IOR for left compared to right VF with sad faces but no such asymmetry for happy faces. Cued N1 amplitudes were suppressed for happy targets but not for sad targets presented to the left VF. Nd amplitudes were enhanced for right-hemispheric sad faces especially with object-based IOR. The results indicate right-hemispheric advantage in the capture of attention by negative emotion especially with object-based selection.     

The effects of attention on ear advantages in dichotic listening to words and affects

This study examined the effects of attention on ear advantages using dichotic listening to words and affects, a focused-attention paradigm. We compared the mixed condition, in which attention is switched between the ears in each trial, to the blocked condition, in which attention is directed to one ear for an entire block of trials. Results showed a decreased right ear advantage for word processing only in the mixed condition and an increased left ear advantage for emotion processing in both attention conditions for hits index. The mixed condition showed smaller laterality effects than the blocked condition for words with respect to hits index, while increasing right ear predominance for intrusions. The greater percentage of intrusions in the right ear for the word task and in the mixed condition suggests that the right ear (left hemisphere) is most vulnerable to attention switching. We posit that the attention manipulation has a greater effect on word processing than on emotion processing and propose that ear advantages reflect a combination of the effects of attentional and structural constraints on lateralisation.     

Investigating sustained attention ability in the elderly by using two different approaches: Inhibiting ongoing behavior versus responding on rare occasions

Previous studies on sustained attention ability in the elderly produced inconsistent results. The aim of this study was to evaluate sustained attention performance in younger and older individuals by using, in a within-subjects design, two versions of the same task (the sustained attention to response task, SART) in which only in the response mode differed: in a traditionally formatted task (TFT), subjects had to respond to rare targets, and in a Go/No-Go task they had to withhold response to rare targets. Results showed that in the TFT SART only the older group exhibited a vigilance decrement. On the contrary, only young individuals showed a vigilance decrement in the Go/No-Go SART. These results showed that older individuals, who also reported less mind wandering and a higher level of motivation, exhibited preserved sustained attention ability in the Go/No-Go SART, which could be explained by increased engagement of cognitive control mechanisms in this population. The discrepancy in performance depending on the approach used also underlines the need for further studies on the nature of attention failures and their underlying mechanisms.