Better safe than sorry: Simplistic fear-relevant stimuli capture attention

It has been consistently demonstrated that fear-relevant images capture attention preferentially over fear-irrelevant images. Current theory suggests that this faster processing could be mediated by an evolved module that allows certain stimulus features to attract attention automatically, prior to the detailed processing of the image. The present research investigated whether simplified images of fear-relevant stimuli would produce interference with target detection in a visual search task. In Experiment 1, silhouettes and degraded silhouettes of fear-relevant animals produced more interference than did the fear-irrelevant images. Experiment 2, compared the effects of fear-relevant and fear-irrelevant distracters and confirmed that the interference produced by fear-relevant distracters was not an effect of novelty. Experiment 3 suggested that fear-relevant stimuli produced interference regardless of whether participants were instructed as to the content of the images. The three experiments indicate that even very simplistic images of fear-relevant animals can divert attention.     

Better safe than sorry: simplistic fear-relevant stimuli capture attention

It has been consistently demonstrated that fear-relevant images capture attention preferentially over fear-irrelevant images. Current theory suggests that this faster processing could be mediated by an evolved module that allows certain stimulus features to attract attention automatically, prior to the detailed processing of the image. The present research investigated whether simplified images of fear-relevant stimuli would produce interference with target detection in a visual search task. In Experiment 1, silhouettes and degraded silhouettes of fear-relevant animals produced more interference than did the fear-irrelevant images. Experiment 2, compared the effects of fear-relevant and fear-irrelevant distracters and confirmed that the interference produced by fear-relevant distracters was not an effect of novelty. Experiment 3 suggested that fear-relevant stimuli produced interference regardless of whether participants were instructed as to the content of the images. The three experiments indicate that even very simplistic images of fear-relevant animals can divert attention.     

Attentional bias to emotional stimuli is altered during moderate- but not high-intensity exercise

Little is known regarding how attention to emotional stimuli is affected during simultaneously performed exercise. Attentional biases to emotional face stimuli were assessed in 34 college students (17 women) using the dot-probe task during counterbalanced conditions of moderate- (heart rate at 45% peak oxygen consumption) and high-intensity exercise (heart rate at 80% peak oxygen consumption) compared with seated rest. The dot-probe task consisted of 1 emotional face (pleasant or unpleasant) paired with a neutral face for 1,000 ms; 256 trials (128 trials for each valence) were presented during each condition. Each condition lasted approximately 10 min. Participants were instructed to perform each trial of the dot-probe task as quickly and accurately as possible during the exercise and rest conditions. During moderate-intensity exercise, participants exhibited significantly greater attentional bias scores to pleasant compared with unpleasant faces (p < .01), whereas attentional bias scores to emotional faces did not differ at rest or during high-intensity exercise (p > .05). In addition, the attentional bias to unpleasant faces was significantly reduced during moderate-intensity exercise compared with that during rest (p < .05). These results provide behavioral evidence that during exercise at a moderate intensity, there is a shift in attention allocation toward pleasant emotional stimuli and away from unpleasant emotional stimuli. Future work is needed to determine whether acute exercise may be an effective treatment approach to reduce negative bias or enhance positive bias in individuals diagnosed with mood or anxiety disorders, or whether attentional bias during exercise predicts adherence to exercise.     

Emotion drives attention: detecting the snake in the grass

Participants searched for discrepant fear-relevant pictures (snakes or spiders) in grid-pattern arrays of fear-irrelevant pictures belonging to the same category (flowers or mushrooms) and vice versa. Fear-relevant pictures were found more quickly than fear-irrelevant ones. Fear-relevant, but not fear-irrelevant, search was unaffected by the location of the target in the display and by the number of distractors, which suggests parallel search for fear-relevant targets and serial search for fear-irrelevant targets. Participants specifically fearful of snakes but not spiders (or vice versa) showed facilitated search for the feared objects but did not differ from controls in search for nonfeared fear-relevant or fear-irrelevant, targets. Thus, evolutionary relevant threatening stimuli were effective in capturing attention, and this effect was further facilitated if the stimulus was emotionally provocative.     

Processing of indexical information requires time: Evidence from change deafness

In three experiments, the efficiency in detecting fear-relevant and fear-irrelevant visual stimuli are compared. A visual search paradigm is used where participants are presented with matrices of different sizes (4 objects/9 objects) and must determine whether all objects are taken from the same category or whether there is a discrepant one. Results from all experiments were consistent with the threat-superiority effect. Participants were quicker when the target was threatening than when it was not. Other indicators confirmed that the detection of threatening targets involves more efficient processes (reduced slopes, absence of position effects). A crucial aspect of these experiments was the comparison of evolutionary-relevant (snakes, spiders, etc.) and modern (guns, syringes, etc.) threats. The threat-superiority effect was repeatedly found for both types of target. Stronger effects were sometimes observed for modern than for evolutionary-relevant threats. The implications for evolutionary explanations of the effect of fear on visual attention are discussed.     

Snakes, spiders, guns, and syringes: how specific are evolutionary constraints on the detection of threatening stimuli?

In three experiments, the efficiency in detecting fear-relevant and fear-irrelevant visual stimuli are compared. A visual search paradigm is used where participants are presented with matrices of different sizes (4 objects/9 objects) and must determine whether all objects are taken from the same category or whether there is a discrepant one. Results from all experiments were consistent with the threat-superiority effect. Participants were quicker when the target was threatening than when it was not. Other indicators confirmed that the detection of threatening targets involves more efficient processes (reduced slopes, absence of position effects). A crucial aspect of these experiments was the comparison of evolutionary-relevant (snakes, spiders, etc.) and modern (guns, syringes, etc.) threats. The threat-superiority effect was repeatedly found for both types of target. Stronger effects were sometimes observed for modern than for evolutionary-relevant threats. The implications for evolutionary explanations of the effect of fear on visual attention are discussed.     

Tracking fear in snake and spider fearful participants during visual search: A multi-response domain study

In visual search tasks snake or spider fearful participants showed shorter reaction times (RTs) to respond to their feared animal (e.g., snake) than to the nonfeared animal (i.e., spider) (Öhman, Flykt, & Esteves, 2001). Here, we used this paradigm with heart rate (HR), RTs, and event-related potential (ERP) measures, to investigate the nature of the responses to the feared animal, a nonfeared (but fear-relevant) animal, and fear-irrelevant target stimuli with snake fearful, spider fearful, and nonfearful participants. Fearful participants showed shorter RTs and evoked larger amplitudes on a late positive potential (LPP; 500–700 ms) for their feared compared to the nonfeared and the fear-irrelevant targets. No relevant significant differences were found on early ERP components and HR measures. These findings do not support an involvement of early information processing in the detection of the feared animal in fearful participants, they favour instead a more elaborated analysis of these complex stimuli to achieve the detection.     

The renewal of extinguished conditioned fear with fear-relevant and fear-irrelevant stimuli by a context change after extinction

The acquisition, extinction, and subsequent recovery of conditioned fear can be influenced by the nature of the conditional stimulus (CS) and the context in which the CS is presented. The combined effects of these factors were examined in a differential fear-conditioning procedure with humans. Fear-relevant or fear-irrelevant CSs were followed by a shock unconditional stimulus (US) during acquisition and presented alone during extinction. The CSs were images presented upon different background contexts. Half the participants received the same context during acquisition and extinction and the remaining received different contexts. All participants received test trials in the same context as acquisition. In Experiment 1 (N=64), a renewal of shock expectancy and skin conductance responses was found during test for fear-relevant and fear-irrelevant CSs when extinction was given in a different context. In Experiment 2 (N=72), renewal for fear-relevant stimuli was enhanced when acquisition and test was given in an indoor office context and extinction in an outdoor bush context. The opposite context configuration produced the strongest renewal for fear-irrelevant stimuli. The return of extinguished conditioned fear can occur to fear-relevant stimuli that are commonly associated with clinical fears and its strength may be enhanced when the stimuli are encountered in certain contexts after extinction.     

The role of fear-relevant stimuli in visual search: a comparison of phylogenetic and ontogenetic stimuli

It has been argued that phylogenetic fear-relevant stimuli elicit preattentive capture of attention. To distinguish between fear relevance and time of appearance in evolutionary history, the authors compare phylogenetic and ontogenetic fear-relevant and fear-irrelevant stimuli in a visual search task. The authors found no evidence for a special role of phylogenetic fear-relevant stimuli; it seems that fear relevance in general is more important than is the evolutionary age. The pattern of results indicates that attention toward threatening stimuli is mainly affected by a late component that prolongs the disengagement of attention.     

Observational conditioning of fear to fear-relevant versus fear-irrelevant stimuli in rhesus monkeys

Two experiments examined whether superior observational conditioning of fear occurs in observer rhesus monkeys that watch model monkeys exhibit an intense fear of fear-relevant, as compared with fear-irrelevant, stimuli. In both experiments, videotapes of model monkeys behaving fearfully were spliced so that it appeared that the models were reacting fearfully either to fear-relevant stimuli (toy snakes or a toy crocodile), or to fear-irrelevant stimuli (flowers or a toy rabbit). Observer groups watched one of four kinds of videotapes for 12 sessions. Results indicated that observers acquired a fear of fear-relevant stimuli (toy snakes and toy crocodile), but not of fear-irrelevant stimuli (flowers and toy rabbit). Implications of the present results for the preparedness theory of phobias are discussed.     

Mortality salience reduces attentional bias for fear-relevant animals

This research investigated the influence of reminders of mortality on biased attention for fear-relevant animals across 2 studies. In each study, participants completed a baseline dot-probe test of attention to fear-relevant animals (snakes and spiders). After random assignment, participants completed a mortality salience or control writing task (about watching television in Study 1 and about writing an important exam in Study 2). Finally, participants completed the dot-probe measure a second time. In both studies, those in the mortality salience condition showed a significant reduction in bias for fear-relevant animals from baseline to post-manipulation, whereas no change was found for those in the control conditions. These data suggest that the previously demonstrated lack of emotional response to mortality salience may, in part, result from the avoidance of fear-relevant stimuli.

Why do they do it? Differences in high-intensity exercise-affect between those with higher and lower intensity preference and tolerance

Evidence suggests high-intensity exercise results in a more negative affective response when compared to moderate- or low-intensity exercise. However, a large number of individuals continue participating in high-intensity exercise, in spite of these supposed declines in affective state.PurposeDetermine whether trait differences influence variability in exercise-affect for those with higher versus lower exercise intensity preference and/or tolerance, and determine the mediating relationship between traits, exercise behavior, and affective states.MethodsUndergraduates (N = 245, 20.3 ± 1.7 yrs, BMI = 23.7 ± 3.8, 60.8% female, 82% regular exercisers) completed the Preference for and Tolerance of the Intensity of Exercise Questionnaire. They then completed a 15-min high-intensity body-weight circuit (HIC), a walk, and a reading condition, where valence (via Feeling Scale), perceived physiological activation (via Felt Arousal Scale), and ratings of perceived exertion were taken prior to, every 3-min during, and 20-min post (P20) condition, while activity enjoyment was assessed immediately post.ResultsMultivariate ANOVAs revealed significant differences (p_s < 0.05) in valence between those with high versus low intensity preferences during HIC at minutes 3 (d = 0.615), 6 (d = 0.772), 9 (d = 0.659), 12 (d = 0.625), 15 (d = 0.632), and at P20 (d = 0.554), and for enjoyment following HIC (d = 0.545), but not for walking or reading conditions.ConclusionsThese findings suggest the intensity-preference trait influences how an individual feels during high-intensity exercise, but has less influence on affect during moderate/lower intensity activities. These differences may be predictive of whether an individual will continue high-intensity exercise programming.     

Visual search with biological threat stimuli: accuracy, reaction times, and heart rate changes

Twenty-four participants were given a visual search task of deciding whether all the pictures in 3 x 3 search arrays contained a target picture from a deviant category, and heart rate was measured. The categories were snakes, spiders, flowers, and mushrooms. Shorter reaction times (RTs) were observed for fear-relevant (snake and spider) targets rather than for fear-irrelevant/neutral (flower and mushroom) targets. This difference was most pronounced for the participants presented with a gray-scale version of the search arrays. The 1st interbeat interval (IBI), after the search array onset, showed an effect of the target, whereas the 2nd IBI also showed an effect of the distractors. The results suggest that controlled processing of the task operates together with automatic processing.     

Moderators of the Exercise/Feeling-State Relationship: The Influence of Self-Efficacy, Baseline, and In-Task Feeling States at Moderate- and High-Intensity Exercise

The present study examined the moderating influence of self-efficacy, baseline feeling states, and in-task feeling states on exercise-related feeling-state changes at moderate- and high-intensity exercise. Physically active females ( N = 60) participated in 1 of 5 conditions: (a) attention control for 30 min, (b) exercise at 50% heart rate reserve (HRR) for 15 min, (c) exercise at 50% HRR for 30 min, (d) exercise at 85% HRR for 15 min, and (e) exercise at 85% HRR for 30 min. The Exercise-Induced Feeling Inventory (EFI; Gauvin & Rejeski, 1993) was completed pre-, during, and post-exercise, while self-efficacy was completed pre-exercise. Multilevel modeling (Bryk & Raudenbaush, 1992) revealed that pre-exercise self-efficacy and in-task tranquility moderated the change in tranquility for high-intensity exercise. Furthermore, baseline feeling states moderated the change in all 4 feeling states. It is recommended that baseline and in-task feeling states and self-efficacy be considered when examining high-intensity exercise.     

Some animal specific fears are more specific than others: Evidence from attention and emotion measures

Using a visual search methodology we investigated the effect of feared animal stimuli on attention. Our results confirmed the important role of emotion on attention. All participants detected fear-relevant stimuli (snakes and spiders) faster than neutral (mushrooms) ones against a background of fruits. In addition, spider fearful participants were sensitized specifically to detect their feared stimulus (spiders), compared to their fear-relevant but non-feared (snakes) and neutral stimuli. However, for participants fearful of snakes there was no significant difference in detection latencies between the feared (snakes) and the fear-relevant but non-feared animal stimuli (spiders). The results from the attention task were mirrored in the emotional ratings, which showed that spider fear was highly specific, whereas snake fear was associated with a more generalized enhanced evaluation of all negative stimuli.     

Maternal Modeling and the Acquisition of Fear and Avoidance in Toddlers: Influence of Stimulus Preparedness and Child Temperament

The aim of the present study was to investigate the influence of maternal modeling on the acquisition of fear and avoidance towards fear-relevant and fear-irrelevant, novel stimuli in a sample of 71 toddlers. Children were shown a rubber snake or spider (fear-relevant objects) and a rubber mushroom or flower (fear-irrelevant objects), which were alternately paired with either negative or positive expression by their mothers. Both stimuli were presented again after a 1- and a 10-min delay, while mothers maintained a neutral expression. The toddlers showed increased fear and avoidance of the objects following negative reaction from their mothers than following positive maternal expression. This was similarly true for both fear-relevant and fear-irrelevant stimuli. In addition, no association was found between child temperament and behavioral responses and a weak association emerged between child temperament and emotional responses. The results demonstrate that young children can rapidly form conditioned emotional and behavioral responses via maternal reactions regardless of stimulus preparedness or child temperament. It is suggested that early maternal modeling may be relevant to a broad spectrum of fearful reactions.     

The Effect of Prior Fear Levels on UCS-expectancy Ratings to a Fear-relevant Stimulus

This study investigated the effect of levels of prior fear to a fear-relevant stimulus on UCS expectancy ratings in a threat conditioning procedure. The results suggested that UCS-expectancy ratings are independently influenced by both the nature of the stimulus (whether it is fear-relevant or fear-irrelevant) and the level of prior fear to the stimulus. Furthermore, significantly higher UCS-expectancy levels caused by prior fear and stimulus type were accompanied in some stages of the experiment by greater magnitudes of skin conductance responses during the stimulus.     

The effects of aerobic exercise on working memory in methamphetamine-dependent patients: Evidence from combined fNIRS and ERP

ObjectiveTo explore the effect of aerobic exercise on working memory according to exercise intensity in patients with methamphetamine (MA) dependence.DesignTwelve-week randomized controlled trial.MethodForty-five MA-dependent patients were divided randomly into three groups participating in 12-week moderate- and high-intensity aerobic exercise interventions and no intervention (control), respectively. Working memory performance was assessed using a 2-back task, and a combined functional near-infrared spectral imaging–event-related potential measure was used to identify spatial and temporal components of the neurofunctional underpinnings of this performance.ResultsHigh-intensity exercise significantly enhanced the discernment aspect of working memory. It also decreased N1 and P2 amplitudes, and increased neural activity in the left dorsolateral prefrontal cortex.ConclusionsThe findings of this study suggest that high-intensity aerobic exercise can enhance working memory and neural activity in MA-dependent patients, and thus that it may serve as an effective therapeutic tool for these patients.     

Acute exercise effects on worry,state anxiety,and feelings of energy and fatigue among young women with probable Generalized Anxiety Disorder: A pilot study

BackgroundLittle is known about the acute effects of exercise among individuals with clinical or subclinical Generalized Anxiety Disorder (GAD).PurposeThus, this study examined worry, state anxiety, and feelings of energy and fatigue responses to acute aerobic exercise and quiet rest, and explored potential moderators of response among young adult women with worry scores indicative of GAD.MethodsSeventeen young women with Penn State Worry Questionnaire scores ≥45 (60 ± 8) completed 30-min treadmill running at 65%–85% heart rate reserve (%HRR) and 30-min seated quiet rest in counterbalanced order. Outcomes included worry, state anxiety, and feelings of energy and fatigue. Two condition X two time repeated measures ANOVA examined differences across condition and time. Hedges’ d effect sizes (95%CI) were calculated to quantify and compare the magnitude of change. Independent-samples t-tests explored potential moderators of outcome response.ResultsTotal exercise time was 35.8 ± 3.4min with a mean 30.3 ± 0.16 in-zone minutes (65%-85%HRR); participants exercised at ∼72.9 ± 0.03 %HRR (range 66%–79%). Compared with quiet rest, acute exercise significantly improved worry engagement, state anxiety, and feelings of energy and fatigue (all p ≤ 0.031). Moderate-to-large (d = 0.44 to 1.69) reductions in state anxiety and feelings of fatigue and improvements in feelings of energy were found. Exercise-induced reductions in worry engagement were significantly larger among non-high trait anxious participants. Compared to normal sleepers, quiet rest significantly increased feelings of fatigue among poor sleepers.ConclusionFindings provide support for the positive effects of acute aerobic exercise on worry, state anxiety, and feelings of energy and fatigue among young women with worry indicative of GAD.     

The preparedness theory of phobias and human safety-signal conditioning

Seligman's preparedness theory of phobias implies that fear-relevant stimuli are contraprepared for safety-signal conditioning. This means that it should be very difficult to establish a fear-relevant stimulus as a safety-signal in nonphobic subjects. This hypothesis was tested in an electrodermal conditioning experiment with a picture of a snake serving as the fear-relevant CS and a picture of a flower serving as the fear-irrelevant CS. College students received discrimination training designed to establish the snake and the flower as safety-signals by nonreinforcing each in compound with a fear-eliciting CS. Although both the snake and the flower became conditioned safety-signals, neither stimulus showed greater safety-signal properties than the other. The results are inconsistent with predictions from preparedness theory.