Threat-induced prosocial behavior: enhanced exogenous attention to protect others from harm.

As social animals, humans tend to voluntarily engage in pro-social behavior to prevent harm to others. However, to what extent prosocial behavior can be reflected at the level of less voluntary cognitive processes remains unclear. Here, we examined how threat to others modulates exogenous attention. Fifty-four participants performed an exogenous spatial cueing task where the participant's performance determined whether electric shocks would be delivered either to themselves or to their anonymous co-participant. Threat of shock to the co-participant elicited orienting and reorienting responses that were faster than in the safe condition and did not differ from performance when participants avoided shocks to themselves. This attentional improvement was not due to speed-accuracy trade off and was associated with arousal, i.e., increased pupil dilation in both threat conditions. Together, these findings suggest that pro-social behavior triggers automatic attentional processes which may be relevant for providing immediate help without relying on reflexive processes.

Emotional modulation of gaze cueing does not depend on a global perceptual processing strategy.

Research on emotional modulation of attention in gaze cueing has resulted in contradictory findings. Some studies found larger gaze cueing effects (GCEs) in response to a fearful gaze cue, whereas others did not. A recent study explained this discrepancy within a cognitive resource account, in which perceptual demands of the task promote a bias toward either a local (discrimination task) or global (localization task) processing strategy. During local processing, the integration of emotional expression with gaze direction is assumed to be impaired, whereas during global processing integration is assumed to be facilitated. In the current study, we investigated the cognitive resource account in three experiments. In Experiment 1, we manipulated task demands by adopting a detection or a localization task whilst both should allow global processing. In Experiments 2 and 3, we induced either a local or global perceptual processing strategy by presenting local or global targets (Experiment 2) or by priming local or global perception prior to the gaze cueing task (Experiment 3). Results showed faster orienting in response to a fearful face cue independent of task demands in Experiment 1. Inducing local and global processing strategies in Experiments 2 and 3 did not affect emotional modulation of the GCE. In contrast, Bayesian analyses provided evidence of absence of such an effect, demonstrating that local or global processing strategies cannot explain the mixed findings obtained in emotional modulation of gaze cueing. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Unconscious processing of coarse visual information during anticipatory threat.

Rapid detection of threats has been proposed to rely on automatic processing of their coarse visual features. However, it remains unclear whether such a mechanism is restricted to detection of threat cues, or whether it reflects a broader sensitivity to even neutral coarse visual information features during states of threat. We used a backward masking task in which participants discriminated the orientation of subliminally presented low (3 cpd) and high (6 cpd) spatial frequency gratings, under threat (of shock) and safe conditions. Visual awareness of the gratings was assessed objectively using an additional localization task. When participants were unaware of the gratings, above chance and improved discrimination of low-spatial frequency gratings was observed under threat compared to safe trials. These findings demonstrate unconscious processing of neutral coarse visual information during threat state, supporting the view that automatic threat detection may rely on a general facilitation of coarse features irrespective of threat content.

The influence of emotional stimuli on the oculomotor system: A review of the literature.

In the past decade, more and more research has been investigating oculomotor behavior in relation to attentional selection of emotional stimuli. Whereas previous research on covert emotional attention demonstrates contradictory results, research on overt attention clearly shows the influence of emotional stimuli on attentional selection. The current review highlights studies that have used eye-movement behavior as the primary outcome measure in healthy populations and focusses on the evidence that emotional stimuli-in particular, threatening stimuli-affect temporal and spatial dynamics of oculomotor programming. The most prominent results from these studies indicate that attentional selection of threatening stimuli is under bottom-up control. Moreover, threatening stimuli seem to have the greatest impact on oculomotor behavior through biased processing via the magnocellular pathway. This is consistent with an evolutionary account of threat processing, which claims a pivotal role for a subcortical network including pulvinar, superior colliculus, and amygdala. Additionally, I suggest a neurobiological model that considers possible mechanisms by which emotional stimuli could affect oculomotor behavior. The present review confirms the relevance of eye-movement measurements in relation to researching emotion in order to elucidate processes involved in emotional modulation of visual and attentional selection.

Right posterior parietal cortex is involved in disengaging from threat: a 1-Hz rTMS study.

The right posterior parietal cortex (PPC) is implicated in spatial attention, but its specific role in emotional spatial attention remains unclear. In this study, we combined inhibitory transcranial magnetic stimulation (TMS) with a fear-conditioning paradigm to test the role of the right PPC in attentional control of task-irrelevant threatening distractors. In a sham-controlled within-subject design, 1-Hz repetitive TMS was applied to the left and right PPC after which participants performed a visual search task with a distractor that was either associated with a loud noise burst (threat) or not (non-threat). Results demonstrated attentional capture across all conditions as evidenced by the typical reaction time costs of the distractor. However, only after inhibitory rTMS to the right PPC reaction time cost in the threatening distractor condition was increased relative to the non-threatening distractor condition, suggesting that attention lingered longer on the threatening distractor. We propose that the right PPC is involved in disengagement of attention from emotionally salient stimuli in order to re-orient attention to task relevant stimuli and may have implications for anxiety disorders associated with difficulties to disengage from threatening stimuli.

Distracted by danger: Temporal and spatial dynamics of visual selection in the presence of threat.

Threatening stimuli are known to influence attentional and visual processes in order to prioritize selection. For example, previous research showed faster detection of threatening relative to nonthreatening stimuli. This has led to the proposal that threatening stimuli are prioritized automatically via a rapid subcortical route. However, in most studies, the threatening stimulus is always to some extent task relevant. Therefore, it is still unclear if threatening stimuli are automatically prioritized by the visual system. We used the additional singleton paradigm with task-irrelevant fear-conditioned distractors (CS+ and CS-) and indexed the time course of eye movement behavior. The results demonstrate automatic prioritization of threat. First, mean latency of saccades directed to the neutral target was increased in the presence of a threatening (CS+) relative to a nonthreatening distractor (CS-), indicating exogenous attentional capture and delayed disengagement of covert attention. Second, more error saccades were directed to the threatening than to the nonthreatening distractor, indicating a modulation of automatically driven saccades. Nevertheless, cumulative distributions of the saccade latencies showed no modulation of threat for the fastest goal-driven saccades, and threat did not affect the latency of the error saccades to the distractors. Together these results suggest that threatening stimuli are automatically prioritized in attentional and visual selection but not via faster processing. Rather, we suggest that prioritization results from an enhanced representation of the threatening stimulus in the oculomotor system, which drives attentional and visual selection. The current findings are interpreted in terms of a neurobiological model of saccade programming.

Awareness of distractors is necessary to generate a strategy to avoid responding to them: A commentary on Lin and Murray (2015).

Lin and Murray published in the 2015 January Issue of Psychological Science a study that claims to have made the surprising discovery of unconscious effects that are stronger than equivalent conscious effects. Specifically, the authors claim to have uncovered dissociable components of aware and unaware orienting and inhibition in exogenous cueing. They suggest an awareness-dependent location-based inhibition mechanism referred to as a negative attentional aftereffect. Here we argue for a simpler explanation, based on established literature, that all they have shown is response inhibition to a consciously perceived cue presented at a fixed location.

Disentangling attention from action in the emotional spatial cueing task.

In the emotional spatial cueing task, a peripheral cue--either emotional or non-emotional--is presented before target onset. A stronger cue validity effect with an emotional relative to a non-emotional cue (i.e., more efficient responding to validly cued targets relative to invalidly cued targets) is taken as an indication of emotional modulation of attentional processes. However, results from previous emotional spatial cueing studies are not consistent. Some studies find an effect at the validly cued location (shorter reaction times compared to a non-emotional cue), whereas other studies find an effect at the invalidly cued location (longer reaction times compared to a non-emotional cue). In the current paper, we explore which parameters affect emotional modulation of the cue validity effect in the spatial cueing task. Results from five experiments in healthy volunteers led to the conclusion that a threatening spatial cue did not affect attention processes but rather indicate that motor processes are affected. A possible mechanism might be that a strong aversive cue stimulus decreases reaction times by means of stronger action preparation. Consequently, in case of a spatially congruent response with the peripheral cue, a stronger cue validity effect could be obtained due to stronger response priming. The implications for future research are discussed.

Conditioned fear modulates visual selection.

Eye movements reflect the dynamic interplay between top-down- and bottom-up-driven processes. For example, when we voluntarily move our eyes across the visual field, salient visual stimuli in the environment may capture our attention, our eyes, or modulate the trajectory of an eye movement. Previous research has shown that the behavioral relevance of a salient stimulus modulates these processes. This study investigated whether a stimulus signaling an aversive event modulates saccadic behavior. Using a differential fear-conditioning procedure, we presented a threatening (conditional stimulus: CS+) and a nonthreatening stimulus distractor (CS-) during an oculomotor selection task. The results show that short-latency saccades deviated more strongly toward the CS+ than toward the CS- distractor, whereas long-latency saccades deviated more strongly away from the CS+ than from the CS- distractor. Moreover, the CS+ distractor captured the eyes more often than the CS- distractor. Together, these results demonstrate that conditioned fear has a direct and immediate influence on visual selection. The findings are interpreted in terms of a neurobiological model of emotional visual processing.

Enhanced visual perception with occipital transcranial magnetic stimulation.

Transcranial magnetic stimulation (TMS) over the occipital pole can produce an illusory percept of a light flash (or 'phosphene'), suggesting an excitatory effect. Whereas previous reported effects produced by single-pulse occipital pole TMS are typically disruptive, here we report the first demonstration of a location-specific facilitatory effect on visual perception in humans. Observers performed a spatial cueing orientation discrimination task. An orientation target was presented in one of two peripheral placeholders. A single pulse below the phosphene threshold applied to the occipital pole 150 or 200 ms before stimulus onset was found to facilitate target discrimination in the contralateral compared with the ipsilateral visual field. At the 150-ms time window contralateral TMS also amplified cueing effects, increasing both facilitation effects for valid cues and interference effects for invalid cues. These results are the first to show location-specific enhanced visual perception with single-pulse occipital pole stimulation prior to stimulus presentation, suggesting that occipital stimulation can enhance the excitability of visual cortex to subsequent perception.

Distribution of attention modulates salience signals in early visual cortex.

Previous research has shown that the extent to which people spread attention across the visual field plays a crucial role in visual selection and the occurrence of bottom-up driven attentional capture. Consistent with previous findings, we show that when attention was diffusely distributed across the visual field while searching for a shape singleton, an irrelevant salient color singleton captured attention. However, while using the very same displays and task, no capture was observed when observers initially focused their attention at the center of the display. Using event-related fMRI, we examined the modulation of retinotopic activity related to attentional capture in early visual areas. Because the sensory display characteristics were identical in both conditions, we were able to isolate the brain activity associated with exogenous attentional capture. The results show that spreading of attention leads to increased bottom-up exogenous capture and increased activity in visual area V3 but not in V2 and V1.

Unconscious attentional orienting to exogenous cues: A review of the literature.

The present paper reviews research that focuses on the dissociation between bottom-up attention and consciousness. In particular, we focus on studies investigating spatial exogenous orienting in the absence of awareness. We discuss studies that use peripheral masked onset cues and studies that use gaze cueing. The results from these studies show that the classic biphasic pattern of facilitation and inhibition, which is characteristic of conscious exogenous cueing can also be obtained with subliminal spatial cues. It is hypothesized that unconscious attentional orienting is mediated by the subcortical retinotectal pathway. Moreover, a possible neural network including superior colliculus, pulvinar and amygdala is suggested as the underlying mechanism.

Unconscious cueing effects in saccadic eye movements--facilitation and inhibition in temporal and nasal hemifield.

The current study investigated whether subliminal spatial cues can affect the oculomotor system. In addition, we performed the experiment under monocular viewing conditions. By limiting participants to monocular viewing conditions, we can examine behavioral temporal-nasal hemifield asymmetries. These behavioral asymmetries may arise from an anatomical asymmetry in the retinotectal pathway. The results show that even though our spatial cues were not consciously perceived they did affect the oculomotor system: relative to the neutral condition, saccade latencies to the validly cued location were shorter and saccade latencies to the invalidly cued location were longer. Although we did not observe an overall inhibition of return effect, there was a reliable effect of hemifield on IOR for those observers who showed an overall IOR effect. More specifically, consistent with the notion that processing via the retinotectal pathway is stronger in the temporal hemifield than in the nasal hemifield we found an IOR effect for cues presented in the temporal hemifield but not for cues presented in the nasal hemifield. We conclude that unconsciously processed spatial cues can affect the oculomotor system. In addition, the observed behavioral temporal-nasal hemifield asymmetry is consistent with retinotectal mediation.

Early and late modulation of saccade deviations by target distractor similarity.

In this study, we investigated the time course of oculomotor competition between bottom-up and top-down selection processes using saccade trajectory deviations as a dependent measure. We used a paradigm in which we manipulated saccade latency by offsetting the fixation point at different time points relative to target onset. In experiment 1, observers made a saccade to a filled colored circle while another irrelevant distractor circle was presented. The distractor was either similar (i.e., identical) or dissimilar to the target. Results showed that the strength of saccade deviation was modulated by target distractor similarity for short saccade latencies. To rule out the possibility that the similar distractor affected the saccade trajectory merely because it was identical to the target, the distractor in experiment 2 was a square shape of which only the color was similar or dissimilar to the target. The results showed that deviations for both short and long latencies were modulated by target distractor similarity. When saccade latencies were short, we found less saccade deviation away from a similar than from a dissimilar distractor. When saccade latencies were long, the opposite pattern was found: more saccade deviation away from a similar than from a dissimilar distractor. In contrast to previous findings, our study shows that task-relevant information can already influence the early processes of oculomotor control. We conclude that competition between saccadic goals is subject to two different processes with different time courses: one fast activating process signaling the saliency and task relevance of a location and one slower inhibitory process suppressing that location.

Eye cannot see it: the interference of subliminal distractors on saccade metrics.

The present study investigated whether subliminal (unconsciously perceived) visual information influences eye movement metrics, like saccade trajectories and endpoints. Participants made eye movements upwards and downwards while a subliminal distractor was presented in the periphery. Results showed that the subliminal distractor interfered with the execution of an eye movement, although the effects were smaller compared to a control experiment in which the distractor was presented supraliminal. Because saccade metrics are mediated by low level brain areas, this indicates that subliminal visual information evokes competition at a very low level in the oculomotor system.

Capture of the eyes by relevant and irrelevant onsets.

During early visual processing the eyes can be captured by salient visual information in the environment. Whether a salient stimulus captures the eyes in a purely automatic, bottom-up fashion or whether capture is contingent on task demands is still under debate. In the first experiment, we manipulated the relevance of a salient onset distractor. The onset distractor could either be similar or dissimilar to the target. Error saccade latency distributions showed that early in time, oculomotor capture was driven purely bottom-up irrespective of distractor similarity. Later in time, top-down information became available resulting in contingent capture. In the second experiment, we manipulated the saliency information at the target location. A salient onset stimulus could be presented either at the target or at a non-target location. The latency distributions of error and correct saccades had a similar time-course as those observed in the first experiment. Initially, the distributions overlapped but later in time task-relevant information decelerated the oculomotor system. The present findings reveal the interaction between bottom-up and top-down processes in oculomotor behavior. We conclude that the task relevance of a salient event is not crucial for capture of the eyes to occur. Moreover, task-relevant information may integrate with saliency information to initiate saccades, but only later in time.

Faster, more intense! The relation between electrophysiological reflections of attentional orienting, sensory gain control, and speed of responding.

Selective visual attention is thought to facilitate goal-directed behavior by biasing the system in advance to favor certain stimuli over others, resulting in their selective processing. The aim of the present study was to gain more insight into the link between control processes that induce a spatial attention bias, target selection processes and speed of responding. To this end, participants performed a spatial cueing task while their brain activity was recorded using EEG. In this task, cues either validly or invalidly predicted the location (left or right) of a forthcoming imperative stimulus or provided no information regarding its location. Cues directing attention in space elicited greater positivity over fronto-central and contralateral posterior scalp regions than non-informative cues starting around 320 ms post cue. Targets appearing at attended vs. unattended locations evoked larger P1 and N1 components, indicating enhanced perceptual processing. Interestingly, detection of targets was fastest in trials with most cue-evoked posterior positivity and in trials with largest target-evoked N1 amplitude. Importantly, the greater the difference in cue-evoked posterior positivity between fast and slow trials, the greater the difference in target-evoked N1 amplitude between fast and slow trials was. Together these findings support neurobiological models of attention that postulate that preparatory attention to a particular location in space can bias the system in advance to favor stimuli presented at the attended location, resulting in a modulation of perceptual processing of incoming stimuli and facilitated goal-directed behavior.