870 resultados para Affective Picture Stimuli
Resumo:
Two experiments examined blink modulation during viewing of pleasant, neutral and unpleasant picture stimuli in non-selected adults (N = 21) and children (N = 60) and children with anxiety disorders (N = 12). Blink reflexes were elicited by a white noise probe of 105 dB at lead stimulus intervals of 60, 240, 3500, and 5000 ms and during intertrial intervals. Blink modulation during unpleasant pictures was significantly different from blink modulation during neutral pictures at the 60 ms lead interval in children whereas adults showed no significant differences. Picture content had no differential effect on the extent of blink modulation for adults or children at the 240 ms lead interval. At the long lead intervals, blink modulation during unpleasant and pleasant pictures was significantly larger than during neutral pictures in adults. Picture valence did not differentially affect the extent of blink modulation at long lead intervals in children. Comparing the extent of blink modulation in anxious and non-selected children, blinks were significantly modulated during unpleasant pictures at the 60 ms lead interval for both groups. However, the extent of blink modulation was larger overall at this very short lead interval in anxious children. Children did not differ at other lead intervals. (C) 2004 Elsevier B.V. All rights reserved.
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Consistent with a negativity bias account, neuroscientific and behavioral evidence demonstrates modulation of even early sensory processes by unpleasant, potentially threat-relevant information. The aim of this research is to assess the extent to which pleasant and unpleasant visual stimuli presented extrafoveally capture attention and impact eye movement control. We report an experiment examining deviations in saccade metrics in the presence of emotional image distractors that are close to a nonemotional target. We additionally manipulate the saccade latency to test when the emotional distractor has its biggest impact on oculomotor control. The results demonstrate that saccade landing position was pulled toward unpleasant distractors, and that this pull was due to the quick saccade responses. Overall, these findings support a negativity bias account of early attentional control and call for the need to consider the time course of motivated attention when affect is implicit
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The present thesis addresses several experimental questions regarding the nature of the processes underlying the larger centro-parietal Late Positive Potential (LPP) measured during the viewing of emotional(both pleasant and unpleasant) compared to neutral pictures. During a passive viewing condition, this modulatory difference is significantly reduced with picture repetition, but it does not completely habituate even after a massive repetition of the same picture exemplar. In order to investigate the obligatory nature of the affective modulation of the LPP, in Study 1 we introduced a competing task during repetitive exposure of affective pictures. Picture repetition occurred in a passive viewing context or during a categorization task, in which pictures depicting any mean of transportation were presented as targets, and repeated pictures (affectively engaging images) served as distractor stimuli. Results indicated that the impact of repetition on the LPP affective modulation was very similar between the passive and the task contexts, indicating that the affective processing of visual stimuli reflects an obligatory process that occurs despite participants were engaged in a categorization task. In study 2 we assessed whether the decrease of the LPP affective modulation persists over time, by presenting in day 2 the same set of pictures that were massively repeated in day 1. Results indicated that the reduction of the emotional modulation of the LPP to repeated pictures persisted even after 1-day interval, suggesting a contribution of long-term memory processes on the affective habituation of the LPP. Taken together, the data provide new information regarding the processes underlying the affective modulation of the late positive potential.
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BACKGROUND: It is well known that there are specific peripheral activation patterns associated with the emotional valence of sounds. However, it is unclear how these effects adapt over time. The personality traits influencing these processes are also not clear. Anxiety disorders influence the autonomic activation related to emotional processing. However, personality anxiety traits have never been studied in the context of affective auditory stimuli. METHODS: Heart rate, skin conductance, zygomatic muscle activity and subjective rating of emotional valence and arousal were recorded in healthy subjects during the presentation of pleasant, unpleasant, and neutral sounds. Recordings were repeated 1 week later to examine possible time-dependent changes related to habituation and sensitization processes. RESULTS AND CONCLUSION: There was not a generalized habituation or sensitization process related to the repeated presentation of affective sounds, but rather, specific adaptation processes for each physiological measure. These observations are consistent with previous studies performed with affective pictures and simple tones. Thus, the measures of skin conductance activity showed the strongest changes over time, including habituation during the first presentation session and sensitization at the end of the second presentation session, whereas the facial electromyographic activity habituated only for the neutral stimuli and the heart rate did not habituate at all. Finally, we showed that the measure of personality trait anxiety influenced the orienting reaction to affective sounds, but not the adaptation processes related to the repeated presentation of these sounds.
Resumo:
Research investigating anxiety-related attentional bias for emotional information in anxious and nonanxious children has been equivocal with regard to whether a bias for fear-related stimuli is unique to anxious children or is common to children in general. Moreover, recent cognitive theories have proposed that an attentional bias for objectively threatening stimuli may be common to all individuals, with this effect enhanced in anxious individuals. The current study investigated whether an attentional bias toward fear-related pictures could be found in nonselected children (n = 105) and adults (n = 47) and whether a sample of clinically anxious children (n = 23) displayed an attentional bias for fear-related pictures over and above that expected for nonselected children. Participants completed a dot-probe task that employed fear-related, neutral, and pleasant pictures. As expected, both adults and children showed a stronger attentional bias toward fear-related pictures than toward pleasant pictures. Consistent with some findings in the childhood domain, the extent of the attentional bias toward fear-related pictures did not differ significantly between anxious children and nonselected children. However, compared with nonselected children, anxious children showed a stronger attentional bias overall toward affective picture stimuli. (C) 2004 Elsevier Inc. All rights reserved.
Resumo:
Bien que les troubles cognitifs soient un aspect essentiel de la schizophrénie, le dysfonctionnement des systèmes émotionnels y est également considéré comme un élément très important de cette maladie d’autant plus que plusieurs régions du cerveau sont concernées par la régulation émotionnelle. Le principal objectif du présent travail était d’explorer, en imagerie par résonnance magnétique fonctionnelle (IRMf), l’effet de la ziprasidone sur les différentes réponses neuronales à l’affichage de stimuli émotionnels au niveau de la région préfrontale,particulièrement dans le cortex cingulaire antérieur [CCA], le cortex orbito-frontal [COF] et le cortex préfrontal dorso-latéral [CPFDL]. Nous avons examiné les activations cérébrales, chez des patients souffrants de schizophrénie avant et après médication à la ziprasidone, en leur présentant des séries d’images émotionnellement chargées (négatives, neutres et positives) associées à différentes instructions quand aux types d’images qu’ils devaient sélectionner (négatives,neutres et positives). Nous avons analysé les différents changements d’activation (avant et après médication) essentiellement pour les valences extrêmes des stimuli (positives et négatives), ensuite nous avons regardé l’effet du type d’instruction sur ces changements. L’échantillon comprenait 13 patients atteints de schizophrénie et 15 témoins sains. Nous avons également effectué une évaluation clinique des symptômes dépressifs, positifs et négatifs de la maladie ainsi que des mesures biochimiques et de poids avant et après 16 semaines de médication. Malgré l’absence de changement significatif sur les mesures cliniques (PANSS et Dépression) avant et après une moyenne de 14.3 semaines de médication à la ziprasidone, plusieurs régions préfrontales (CCA, COF, CPDL) ont sensiblement accru leur réponse aux stimuli positifs par rapport aux stimuli négatifs. En outre, dans les régions habituellement impliquées dans le contrôle cognitif (CCA et CPFDL), cette tendance s'est accentuée lorsque les patients ont été invités à ne sélectionner que les stimuli négatifs (effet du type d’instruction). Nous avons également trouvé plusieurs similitudes dans le fonctionnement préfrontal (à la fois dans le volume et la force d'activation) entre les contrôles sains et les patients après médication en tenant compte du type d’instruction plus que de la valence émotionnelle des images. Pour conclure, les résultats de la présente étude suggèrent que le traitement antipsychotique avec la ziprasidone améliore le fonctionnement cognitif lié au traitement de l'information émotionnelle dans le cortex préfrontal chez les patients souffrant de schizophrénie. Étant donné le mécanisme d'action neuro-pharmacologique de la ziprasidone (plus d'affinité pour la sérotonine que pour les récepteurs de la dopamine dans le cortex préfrontal), nous pensons que nos résultats démontrent que le contrôle cognitif et la régulation des réactions face à des stimuli émotionnellement chargés dans la schizophrénie sont liés à une plus forte concentration de dopamine dans les voies préfrontales.
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BACKGROUND: Clinical evidence suggests a link between vestibular dysfunctions and mood disorders. No study has yet investigated mood and affective control during vestibular stimulation in healthy participants. OBJECTIVE: We predicted a modulating effect of caloric vestibular stimulation (CVS) on affective control measured in an affective Go/NoGo task (AGN). METHODS: Thirty-two participants performed an AGN task while they were exposed to cold left or right ear CVS (20 °C) and sham stimulation (37 °C). In each block, either positive or negative pictures (taken from the International Affective Picture System) were defined as targets. Participants had to respond to targets (Go), and withhold responses to distractors (NoGo). RESULTS: The sensitivity index d' (hits - false alarms) was used to measure affective control. Affective control improved during right ear CVS when viewing positive stimuli (P = .005), but decreased during left ear CVS when compared to sham stimulation (P = .009). CVS had a similar effect on positive mood ratings (Positive and Negative Affect Schedule). Positive mood ratings decreased during left ear CVS when compared to sham stimulation, but there was no effect after right ear CVS. DISCUSSION: The results suggest that CVS, depending on side of stimulation, has a modulating effect on mood and affective control. The results complement previous findings in manic patients and provide new evidence for the clinical potential of CVS.
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Recent studies have shown that vestibular stimulation can influence affective processes. In the present study, we examined whether emotional information can also modulate vestibular perception. Participants performed a vestibular discrimination task on a motion platform while viewing emotional pictures. Six different picture categories were taken from the International Affective Picture System: mutilation, threat, snakes, neutral objects, sports and erotic pictures. Using a Bayesian hierarchical approach we were able to show that vestibular discrimination improved when participants viewed emotionally negative pictures (mutilation, threat, snake) when compared to neutral objects. There was no difference in vestibular discrimination while viewing emotionally positive compared to neutral pictures. We conclude that some of the mechanisms involved in the processing of vestibular information are also sensitive to emotional content. Emotional information signals importance and mobilizes the body for action. In case of danger, a successful motor response requires precise vestibular processing. Therefore, negative emotional information improves processing of vestibular information.
Resumo:
Recent studies have shown that vestibular stimulation can influence affective processes. In the present study, we examined whether emotional information can also modulate vestibular perception. Participants performed a vestibular discrimination task on a motion platform while viewing emotional pictures. Six different picture categories were taken from the International Affective Picture System: mutilation, threat, snakes, neutral objects, sports and erotic pictures. Using a Bayesian hierarchical approach we were able to show that vestibular discrimination improved when participants viewed emotionally negative pictures (mutilation, threat, snake) when compared to neutral objects. There was no difference in vestibular discrimination while viewing emotionally positive compared to neutral pictures. We conclude that some of the mechanisms involved in the processing of vestibular information are also sensitive to emotional content. Emotional information signals importance and mobilizes the body for action. In case of danger, a successful motor response requires precise vestibular processing. Therefore, negative emotional information improves processing of vestibular information.
Resumo:
Recent studies have shown that vestibular stimulation can influence affective processes. In the present study, we examined whether emotional information can also modulate vestibular perception. Participants performed a vestibular discrimination task on a motion platform while viewing emotional pictures. Six different picture categories were taken from the International Affective Picture System: mutilation, threat, snakes, neutral objects, sports, and erotic pictures. Using a Bayesian hierarchical approach, we were able to show that vestibular discrimination improved when participants viewed emotionally negative pictures (mutilation, threat, snake) when compared to neutral/positive objects. We conclude that some of the mechanisms involved in the processing of vestibular information are also sensitive to emotional content. Emotional information signals importance and mobilizes the body for action. In case of danger, a successful motor response requires precise vestibular processing. Therefore, negative emotional information improves processing of vestibular information.
Resumo:
Behavioral inhibition model suggests the generation of anxiety is related with over-inhibition. For knowing about anxiety better, we used event-related potential (ERP) technique to explore the underlying mechanism of executive inhibition under the emotional distracter in high and low trait-anxious groups. Firstly, we set up the Chinese affective picture system (CAPS) as the stimuli of subsequent experiments. Secondly, we screened the high and low trait-anxious participants using the State-Trait Anxiety Inventory. In the first ERP study, a modified oddball paradigm was used with the positive, neutral and negative pictures as novel stimuli and the potentials evoked by three types pictures were analyzed. In the second ERP study, the same paradigm with higher task load was employed to examine the interaction of anxious level and emotion. Main results as follows: 1. CAPS consisted of 852 pictures was assessed via three dimensionalities, valence, arousal and dominance. The standard deviation of scores on valence and dominance was more than the standard deviation of scores on dimension of arousal. Scatter plot showed that the score distributing on the dimension of valence and arousal was wide in CAPS. 2. In both high and low trait-anxiety groups, the amplitudes of N2 and P3 of negative pictures were greater and smaller respectively as compared with neutral and positive pictures, which suggested all participants no matter what anxious level required more inhibition processing to negative information than others. 3. With increasing of task load, the P3 amplitudes of negative pictures in high anxious group were reduced relative to neutral pictures. In addition, in high anxious group, the P3 amplitudes of positive pictures had the same changes as those of negative ones. Whereas, the reduced P3 of positive pictures were not observed in low anxious group. The results showed the high anxious participants employed the same inhibitory strategy to the positive distracter as the negative distracter, which possibly the over-inhibition processing was involved in this group. 4. Dipole source analysis found cingulate may be involved in executive inhibition processing. In sum, as for the inhibition, high and low anxious group both is sensitive to negative information. However, in the high load situation, due to the shortness of cognitive resources, the high anxious individual represents the general sensitivity to all emotional information. These results gave the electrophysiological evidence for over-inhibition in high trait-anxiety group.
Resumo:
Une des théories actuellement prépondérante pour expliquer le déclin cognitif observé chez les personnes âgées est une perte généralisée de la fonction inhibitrice. En revanche, de plus en plus d’études révèlent un maintien et même un gain sur le plan émotionnel chez les âgés. Afin de caractériser l’effet de l’âge sur la fonction inhibitrice et sur les émotions, nous avons utilisé le paradigme bien connu du réflexe acoustique de sursaut et de son inhibition par le prépulse, un phénomène reconnu comme reflétant le filtrage sensorimoteur, soit une mesure pré-attentionnelle d’inhibition. Le réflexe acoustique de sursaut est une réponse du corps tout entier à un bruit fort et inattendu et a été mesuré via la magnitude et la latence du clignement des yeux. La présentation d’un son faible (prépulse) quelques millisecondes avant le bruit de sursaut réduit la réponse de sursaut. Deux groupes de participants (jeunes adultes et âgés) ont visionné des images plaisantes, neutres et déplaisantes issues du International Affective Picture System (IAPS), lesquelles étaient associées à des stimuli auditifs évaluant le réflexe acoustique de sursaut et son inhibition par le prépulse. Les résultats démontrent que le réflexe de sursaut est modulé différemment par les émotions chez les jeunes adultes et les âgés. Plus particulièrement, les adultes âgés ont un plus grand réflexe de sursaut que les jeunes adultes lorsqu’ils visionnent des images plaisantes et neutres. Le processus d’inhibition par le prépulse est également modulé différemment par les émotions chez les âgés et les jeunes adultes: les âgés ont une plus grande inhibition du réflexe de sursaut que les jeunes adultes lorsqu’ils visionnent des images plaisantes et déplaisantes, mais ils ne diffèrent pas des jeunes adultes pour les images neutres. Dans l’ensemble, les résultats obtenus ne sont pas compatibles avec une perte d’inhibition chez les adultes âgés, et supportent plutôt un biais émotionnel positif.
Resumo:
Among younger adults, the ability to willfully regulate negative affect, enabling effective responses to stressful experiences, engages regions of prefrontal cortex (PFC) and the amygdala. Because regions of PFC and the amygdala are known to influence the hypothalamic-pituitary-adrenal axis, here we test whether PFC and amygdala responses during emotion regulation predict the diurnal pattern of salivary cortisol secretion. We also test whether PFC and amygdala regions are engaged during emotion regulation in older (62- to 64-year-old) rather than younger individuals. We measured brain activity using functional magnetic resonance imaging as participants regulated (increased or decreased) their affective responses or attended to negative picture stimuli. We also collected saliva samples for 1 week at home for cortisol assay. Consistent with previous work in younger samples, increasing negative affect resulted in ventral lateral, dorsolateral, and dorsomedial regions of PFC and amygdala activation. In contrast to previous work, decreasing negative affect did not produce the predicted robust pattern of higher PFC and lower amygdala activation. Individuals demonstrating the predicted effect (decrease s attend in the amygdala), however, exhibited higher signal in ventromedial prefrontal cortex (VMPFC) for the same contrast. Furthermore, participants displaying higher VMPFC and lower amygdala signal when decreasing compared with the attention control condition evidenced steeper, more normative declines in cortisol over the course of the day. Individual differences yielded the predicted link between brain function while reducing negative affect in the laboratory and diurnal regulation of endocrine activity in the home environment.
Resumo:
In this research, a cross-model paradigm was chosen to test the hypothesis that affective olfactory and auditory cues paired with neutral visual stimuli bearing no resemblance or logical connection to the affective cues can evoke preference shifts in those stimuli. Neutral visual stimuli of abstract paintings were presented simultaneously with liked and disliked odours and sounds, with neutral-neutral pairings serving as controls. The results confirm previous findings that the affective evaluation of previously neutral visual stimuli shifts in the direction of contingently presented affective auditory stimuli. In addition, this research shows the presence of conditioning with affective odours having no logical connection with the pictures.
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Emotional reactivity and the time taken to recover, particularly from negative, stressful, events, are inextricably linked, and both are crucial for maintaining well-being. It is unclear, however, to what extent emotional reactivity during stimulus onset predicts the time course of recovery after stimulus offset. To address this question, 25 participants viewed arousing (negative and positive) and neutral pictures from the International Affective Picture System (IAPS) followed by task-relevant face targets, which were to be gender categorized. Faces were presented early (400–1500 ms) or late (2400–3500 ms) after picture offset to capture the time course of recovery from emotional stimuli. Measures of reaction time (RT), as well as face-locked N170 and P3 components were taken as indicators of the impact of lingering emotion on attentional facilitation or interference. Electrophysiological effects revealed negative and positive images to facilitate face-target processing on the P3 component, regardless of temporal interval. At the individual level, increased reactivity to: (1) negative pictures, quantified as the IAPS picture-locked Late Positive Potential (LPP), predicted larger attentional interference on the face-locked P3 component to faces presented in the late time window after picture offset. (2) Positive pictures, denoted by the LPP, predicted larger facilitation on the face-locked P3 component to faces presented in the earlier time window after picture offset. These results suggest that subsequent processing is still impacted up to 3500 ms after the offset of negative pictures and 1500 ms after the offset of positive pictures for individuals reacting more strongly to these pictures, respectively. Such findings emphasize the importance of individual differences in reactivity when predicting the temporality of emotional recovery. The current experimental model provides a novel basis for future research aiming to identify profiles of adaptive and maladaptive recovery.