Effects Of Emotional Stimuli Research Articles

Effects of emotional stimuli on cardiovascular responses in patients with essential hypertension based on brain/behavioral systems.

Effects of emotional stimuli on hemodynamics in patients with essential hypertension based on brain/behavioral systems have not been studied broadly. Eighty five essential hypertensive male patients who had completed Carver-White BIS/BAS scale were enrolled to the study. Later, 25 BIS and 25 BAS patients were selected and their blood pressure and heart rate were recorded prior to stimuli induction. Participants were then exposed to stressor pictures. After that, 15 minutes of relaxation and cognitive tasks were performed. Finally, the participants were exposed to pleasant pictures. The blood pressure and heart rate were recorded after presenting of 2 stimuli. Our study showed that BIS patients achieved higher scores in diastolic blood pressure and heart rate in comparison with BAS patients after presenting stressful stimuli. Also, BAS patients achieved lower scores in systolic blood pressure and heart rate in comparison with BIS patients after presenting pleasant stimuli. In summary, BIS patients experience negative emotions more than BAS patients. Therefore, the role of induced mood states is important in relation to physical health.

Immediate effects of exposure to positive and negative emotional stimuli on visual search characteristics in patients with unilateral neglect

The performance of patients with unilateral neglect (UN) in tasks demanding visual attention is characterized by contralesional disadvantage which is markedly unstable in magnitude. Such instability of the attentional system is seen very clearly in clinical practice and thus far has no satisfying explanation. Here we examined the immediate effect of exposure to non-lateralized emotional stimuli on UN patients' attentional bias and performance variability. We tested eight right-hemisphere damaged stroke patients with left-sided neglect and eight age-matched healthy subjects in a visual conjunction-search task, each trial performed immediately after viewing a centrally-presented picture, which was emotionally negative, positive or neutral. Both performance bias and variability in performing the search task was analyzed as a function of the valence of the picture, and a method for analyzing reaction time (RT) variance in a small sample is introduced. Overall, UN subjects, but not controls, were slower and more variable in their RT for left- compared to right-sided targets. In the UN group, detecting left-sided targets was significantly slower in trials that followed presentation of negative pictures as compared to positive pictures, regardless of the fact that both picture types were judged as equally arousing by the patients. Moreover, UN patients exhibited larger performance variance on the left then on the right, and negative emotional stimuli were associated with larger variance asymmetry than positive emotional stimuli. Examining the coefficient of variation pointed to a possible dissociation between the effects of emotional stimuli on the lateralized RT mean (reflecting attentional bias) and on the lateralized RT variance (reflecting system instability). We conclude that emotional stimuli affect the spatial imbalance of both performance speed and stability in UN patients.

Happiness takes you right: The effect of emotional stimuli on line bisection

Emotion recognition is mediated by a complex network of cortical and subcortical areas, with the two hemispheres likely being differently involved in processing positive and negative emotions. As results on valence-dependent hemispheric specialisation are quite inconsistent, we carried out three experiments with emotional stimuli with a task being sensitive to measure specific hemispheric processing. Participants were required to bisect visual lines that were delimited by emotional face flankers, or to haptically bisect rods while concurrently listening to emotional vocal expressions. We found that prolonged (but not transient) exposition to concurrent happy stimuli significantly shifted the bisection bias to the right compared to both sad and neutral stimuli, indexing a greater involvement of the left hemisphere in processing of positively connoted stimuli. No differences between sad and neutral stimuli were observed across the experiments. In sum, our data provide consistent evidence in favour of a greater involvement of the left hemisphere in processing positive emotions and suggest that (prolonged) exposure to stimuli expressing happiness significantly affects allocation of (spatial) attentional resources, regardless of the sensory (visual/auditory) modality in which the emotion is perceived and space is explored (visual/haptic).

The effects of emotional stimuli on target detection: Indirect and direct resource costs

The present study was designed to explore the performance costs of negative emotional stimuli in a vigilance task. Forty participants (20 women) performed a vigilance task in two conditions: one with task-irrelevant negative-arousing pictures and one with task-irrelevant neutral pictures. In addition to performance, we measured subjective state (energetic arousal, tense arousal, task-related and task-unrelated thoughts) and frontal cerebral activity with near infrared spectroscopy. Overall performance in the negative picture condition was lower than in the neutral picture condition and the negative picture condition had elevated levels of energetic arousal, tense arousal and task-related thoughts. Moreover, there was a significant relationship between the impact of the negative pictures on tense arousal and task-related thoughts and the impact of the negative pictures on performance (in comparison to the neutral picture stimuli task). These results provide support for indirect cost models of negative emotional stimuli on target detection performance.

Emotion Modulation of Visual Attention: Categorical and Temporal Characteristics

BackgroundExperimental research has shown that emotional stimuli can either enhance or impair attentional performance. However, the relative effects of specific emotional stimuli and the specific time course of these differential effects are unclear.Methodology/Principal FindingsIn the present study, participants (n = 50) searched for a single target within a rapid serial visual presentation of images. Irrelevant fear, disgust, erotic or neutral images preceded the target by two, four, six, or eight items. At lag 2, erotic images induced the greatest deficits in subsequent target processing compared to other images, consistent with a large emotional attentional blink. Fear and disgust images also produced a larger attentional blinks at lag 2 than neutral images. Erotic, fear, and disgust images continued to induce greater deficits than neutral images at lag 4 and 6. However, target processing deficits induced by erotic, fear, and disgust images at intermediate lags (lag 4 and 6) did not consistently differ from each other. In contrast to performance at lag 2, 4, and 6, enhancement in target processing for emotional stimuli was observed in comparison to neutral stimuli at lag 8.Conclusions/SignificanceThese findings suggest that task-irrelevant emotion information, particularly erotica, impairs intentional allocation of attention at early temporal stages, but at later temporal stages, emotional stimuli can have an enhancing effect on directed attention. These data suggest that the effects of emotional stimuli on attention can be both positive and negative depending upon temporal factors.

The Effect of Emotional Stimuli on Source Memory: Theoretical Models and Current Research*

Source memory refers to memory for the source of information (e.g., memory for how information is acquired or memory for the modality thorough which information is acquired). Emotional stimuli refers to those stimuli that can arouse positive or negative emotions in individuals. With regard to the effect of emotional stimuli on source memory, the research findings have been controversial. Integrating the relevant research findings, the attention narrowing theory and the priority binding theory were described, and the current experimental studies were summarized that respectively demonstrate the enhancement, reduction and null effect of emotional stimuli on source memory. Finally the limitations of the current research and the directions for future research were pointed out.

Reduced memory for the spatial and temporal context of unpleasant words

Emotional stimuli are consistently better remembered than neutral stimuli. However, the reported effects of emotional stimuli on source memory are less consistent. In four experiments, we examined spatial and temporal source memory and free recall for emotional words previously studied in an fMRI experiment. In the fMRI experiment, the unpleasant but not the pleasant words were shown to activate the amygdala. In the experiments reported here, spatial and temporal source memory were reduced for the unpleasant words compared to pleasant and neutral words. Reduced spatial memory for unpleasant words was observed across studies that varied the specific stimuli, task conditions, and incidental versus intentional encoding instructions. Free recall was enhanced for the pleasant and unpleasant words compared to neutral words. The results demonstrate reduced source memory for unpleasant words even when item recall is enhanced. Our findings are consistent with prior reports of amygdala-mediated amnestic effects evoked by unpleasant stimuli.

Visual evoked potentials, heart rate responses and memory to emotional pictorial stimuli

Although the effects of emotional stimuli on event-related cortical potentials, heart rate, and memory have been extensively studied, the association of these variables in a single study has been neglected. The influence of pleasant, unpleasant, and neutral photographic slides on visual evoked potentials (VEPs), heart rate responses, and free recall, was investigated in 20 normal subjects. VEPs were recorded from Cz and Pz locations, and analyses were performed on both amplitudes and latencies of identifiable endogenous peaks (P2, N2 and P3), and mean amplitude in the 100–200-ms, 400–600-ms, and 600–900-ms latency ranges. An emotional effect was present on VEPs starting from about 282 ms on, as revealed by the N2, P3, and late components. Both pleasant and unpleasant slides yielded larger cortical positivity as compared to neutral ones. Peak latencies did not show any emotional effect. Heart rate data showed a deceleratory response that was larger to unpleasant slides. Free recall of the projected slides showed a better performance for emotional slides compared to neutral ones. VEPs and memory data showed the same pattern: both pleasant and unpleasant slides induced larger positivity in the event-related potentials and were better remembered than neutral slides. Positive correlations were found between the late negative VEPs component (600–900 ms), recorded from Cz, and heart rate deceleration ( r=0.62), and between P3 (at Pz location) and the number of remembered slides ( r=0.53). © 1997 Elsevier Science B.V.

Effects of unattended emotional stimuli on color-naming performance

The effect of irrelevant emotional and neutral stimuli on the performance of a color-naming task is examined with two groups of subjects: pilots and bus drivers. It is found that (1) the emotional stimuli disrupt performance in both groups, (2) the decrement in performance is relatively larger in the pilot group, and (3) the effect of the emotional stimuli appears to persist over time.

The Effect of Emotional Stimuli on Behavior in the Multiple Choice Situation

Three groups of 18 albino rats each were given twenty successive freechoice trials per day for seven days, i. e., a conditioning period, in a semicircular maze which had eight equal goalboxes. The following day was an extinction period of sixty trials. The groups differed with respect to the period in which they received the emotional stimuli. Group EC received them immediately before each of the last five days of the conditioning period, and Group EE was given immediately before the extinction period. Group C did not receive them during all periods.The emotional stimuli consisted of three different components; i. e., the electric shock through a grid, the bright light and the loud sound, which simultaneously given for ten seconds at intervals of five seconds during five minutes at a small pen-box placed in another room.In Group EC the emotional stimuli gradually decreased behavior variability until the 5th or 6th day of the conditioning period. Differences in behavior variability between Group EC and Group C during the last five days of conditioning were statistically significant. Although Group C indicated a progressive decrement of behavior variability in extinction, the decremental effect of the emotinal stimuli on behavior variability was found at the later stage of extinction in Group EE. But jumping responses in Group EE increased from the early stage of the extinction period. In the previous experiment and in Group C, it was found that these jumping responses were characteristic of the later stage of extinction. So the emotional stimuli given before extinction might facilitate an appearance of some emotional aspects which ordinarily occurred at the later stage of extinction.

The effect of emotional stimuli on the activity level of the white rat.

The effect of emotional stimuli on the activity level of the white rat.