High-arousal Pictures Research Articles

Recognizing images: The role of motivational significance, complexity, social content, age, and gender.

Memory for affective events plays an important role in determining people's behavior and well-being. Its determinants are far from being completely understood. We investigated how recognition memory for affective pictures depends on pictures' motivational significance (valence and arousal), complexity (figure-ground compositions vs. scenes), and social content (pictures with people vs. without people) and on observers' age and gender. Younger, middle-aged, and older adults viewed 84 pictures depicting real-life situations. After a break, the participants viewed 72 pictures, half of which had been viewed previously and half of which were novel, and were asked to endorse whether each picture was novel or had been presented previously. Hits, false alarms, and overall performance (discrimination accuracy) were our dependent variables. The main findings were that, across participants, recognition memory was better for unpleasant than pleasant pictures and for pictures depicting people than pictures without people. Low-arousal pictures were more accurately recognized than high-arousal pictures, and this effect was significantly larger among middle-aged and older adults than younger adults. Recognition memory worsened across adulthood, and this decline was steeper among men than women. Middle-aged and older women outperformed their male counterparts. This study suggests that how well we are able to successfully discriminate previously seen pictorial stimuli from novel stimuli depends on several pictures' properties related to their motivational significance and content, and on observer's age and gender.

Rating of Affective Pictures of Low and High Arousal Domain among Malaysian Population

Affective pictures are being used in different neuropsychology and neurophysiology studies for the assessment of cognitive function including attention and emotion. This research aims to determine the arousal domain of normative affective pictures from International Affective Picture System (IAPS) with Malaysian population using Self-Assessment Manikin (SAM) then to develop and customize an additional set of affective picture database with Malaysian population using SAM. There were 72 completed data from Malaysian participants were selected to rate a total of 166 pictures in the arousal (low to high) domain of affective dimension using SAM. Rating of the arousal domain of normative affective pictures from IAPS with Malaysian population revealed Malaysian population showed higher score significantly (p<0.001), 4.67± 0.62 than North American (NA) population, 2.78 ± 0.41 with significant correlation (r = 0.254, p = 0.021) between two sample means. The rating of arousal (low to high) domain of affective picture database with Malaysian population showed the overall mean differences among all low arousal pictures, 4.67± 0.62 and all high arousal pictures, 5.06 ± 0.54 with highly significant (p<0.001). The study of affective picture rating revealed the rating of arousal value through SAM with the Malaysian population is probable and reliable, but the higher arousal value of affective pictures in Malaysian population compare to NA population which could be from large sample size in NA or could be from cross cultural variations suggesting special attention needed in using this IAPS affective pictures for research in Malaysian population.

Modulating Effects of Emotional Valence on Recognition Memory for High-Arousal Pictures

The main aim of this paper was to provide new evidence on the effects of valence on recognition memory of emotional pictures, on the basis of rigorous experimental control of stimulus material. Valence was manipulated using pleasant and unpleasant pictures, keeping arousal constant at a high level. A reference condition with a neutral value in both dimensions was also included. We found greater discrimination and a more conservative response bias, as well as slower recognition decisions, for pleasant pictures. Also worthy of mention is the high positive correlation between response times and discrimination measures just for such pictures. These results would be consistent with an adaptive interpretation based on motivation and personal relevance of emotional information.

Visualizing the brain connectivity during negative emotion processing– An EEG study

Visualizing the brain connectivity during negative emotion processing– An EEG study

Visualization of Brain Connectivity during Emotion induction

Visualization of Brain Connectivity during Emotion induction

The impact of attention on judgments of frequency and duration.

Previous studies that examined human judgments of frequency and duration found an asymmetrical relationship: While frequency judgments were quite accurate and independent of stimulus duration, duration judgments were highly dependent upon stimulus frequency. A potential explanation for these findings is that the asymmetry is moderated by the amount of attention directed to the stimuli. In the current experiment, participants' attention was manipulated in two ways: (a) intrinsically, by varying the type and arousal potential of the stimuli (names, low-arousal and high-arousal pictures), and (b) extrinsically, by varying the physical effort participants expended during the stimulus presentation (by lifting a dumbbell vs. relaxing the arm). Participants processed stimuli with varying presentation frequencies and durations and were subsequently asked to estimate the frequency and duration of each stimulus. Sensitivity to duration increased for pictures in general, especially when processed under physical effort. A large effect of stimulus frequency on duration judgments was obtained for all experimental conditions, but a similar large effect of presentation duration on frequency judgments emerged only in the conditions that could be expected to draw high amounts of attention to the stimuli: when pictures were judged under high physical effort. Almost no difference in the mutual impact of frequency and duration was obtained for low-arousal or high-arousal pictures. The mechanisms underlying the simultaneous processing of frequency and duration are discussed with respect to existing models derived from animal research. Options for the extension of such models to human processing of frequency and duration are suggested.

RTMS on left prefrontal cortex contributes to memories for positive emotional cues: A comparison between pictures and words

The present research explored the cortical correlates of emotional memories in response to words and pictures. Subjects’ performance (Accuracy Index, AI; response times, RTs; RTs/AI) was considered when a repetitive Transcranial Magnetic Stimulation (rTMS) was applied on the left dorsolateral prefrontal cortex (LDLPFC). Specifically, the role of LDLPFC was tested by performing a memory task, in which old (previously encoded targets) and new (previously not encoded distractors) emotional pictures/words had to be recognized. Valence (positive vs. negative) and arousing power (high vs. low) of stimuli were also modulated. Moreover, subjective evaluation of emotional stimuli in terms of valence/arousal was explored. We found significant performance improving (higher AI, reduced RTs, improved general performance) in response to rTMS. This “better recognition effect” was only related to specific emotional features, that is positive high arousal pictures or words. Moreover no significant differences were found between stimulus categories. A direct relationship was also observed between subjective evaluation of emotional cues and memory performance when rTMS was applied to LDLPFC. Supported by valence and approach model of emotions, we supposed that a left lateralized prefrontal system may induce a better recognition of positive high arousal words, and that evaluation of emotional cue is related to prefrontal activation, affecting the recognition memories of emotions.

Electrodermal activity processing: a convex optimization approach.

This paper reports on a novel model based on convex optimization methods for the analysis of the skin conductance (SC) as response of the electrodermal activity (EDA) to affective stimuli. Starting from previous assessed methodological approaches, this new model proposes a decomposition of SC into tonic and phasic components through the solution of a convex optimization problem. Previous knowledge about the physiology of the EDA is accounted for by means of an appropriate choice of constraints and regularizers. In order to test the effectiveness of the new approach, an experimental session in which 9 healthy subjects were stimulated using affective pictures gathered from the IAPS database was designed and carried out. The experimental session included series of negative-valence high-arousal images and series of neutral images, with an inter-stimulus interval of about 2 seconds for both neutral and high arousal pictures. Next, a statistical analysis was performed on a set of features extracted from the phasic driver and the tonic signal estimated by the model. Results showed that the phasic driver extracted from the model was able to strongly distinguish arousal sessions from neutral ones. Conversely, no significant difference was found for the tonic components. This experimental findings are consistent with the literature and confirm that the phasic component is strictly related to changes in the sympathetic activity of the autonomic nervous system. Although preliminary, these results are very encouraging and future work will progress to further validate the model through specific and controlled experiments.

Concurrent emotional pictures modulate temporal order judgments of spatially separated audio-tactile stimuli

Although attention can be captured toward high-arousal stimuli, little is known about how perceiving emotion in one modality influences the temporal processing of non-emotional stimuli in other modalities. We addressed this issue by presenting observers spatially uninformative emotional pictures while they performed an audio-tactile temporal-order judgment (TOJ) task. In Experiment 1, audio-tactile stimuli were presented at the same location straight ahead of the participants, who had to judge “which modality came first?”. In Experiments 2 and 3, the audio-tactile stimuli were delivered one to the left and the other to the right side, and participants had to judge “which side came first?”. We found both negative and positive high-arousal pictures to significantly bias TOJs towards the tactile and away from the auditory event when the audio-tactile stimuli were spatially separated; by contrast, there was no such bias when the audio-tactile stimuli originated from the same location. To further examine whether this bias is attributable to the emotional meanings conveyed by the pictures or to their high arousal effect, we compared and contrasted the influences of near-body threat vs. remote threat (emotional) pictures on audio-tactile TOJs in Experiment 3. The bias manifested only in the near-body threat condition. Taken together, the findings indicate that visual stimuli conveying meanings of near-body interaction activate a sensorimotor functional link prioritizing the processing of tactile over auditory signals when these signals are spatially separated. In contrast, audio-tactile signals from the same location engender strong crossmodal integration, thus counteracting modality-based attentional shifts induced by the emotional pictures.

Individual EEG differences in affective valence processing in women with low and high neuroticism

ObjectiveIn this study, individual differences in brain electrophysiology during positive and negative affective valence processing in women with different neuroticism scores are quantified. MethodsTwenty-six women scoring high and low on neuroticism participated on this experiment. A support vector machine (SVM)-based classifier was applied on the EEG single trials elicited by high arousal pictures with negative and positive valence scores. Based on the accuracy values obtained from subject identification tasks, the most distinguishing EEG channels among participants were detected, pointing which scalp regions show more distinct patterns. ResultsSignificant differences were obtained, in the EEG heterogeneity between positive and negative valence stimuli, yielding higher accuracy in subject identification using negative pictures. Regarding the topographical analysis, significantly higher accuracy values were reached in occipital areas and in the right hemisphere (p<0.001). ConclusionsMainly, individual differences in EEG can be located in parietooccipital regions. These differences are likely to be due to the different reactivity and coping strategies to unpleasant stimuli in individuals with high neuroticism. In addition, the right hemisphere shows a greater individual specificity. SignificanceAn SVM-based classifier asserts the individual specificity and its topographical differences in electrophysiological activity for women with high neuroticism compared to low neuroticism.

A Positivity Effect in Older Adults’ Memorability Judgments of Pictures

Background/Study Context: A growing literature suggests that older adults are biased to preferentially cognitively process positively valenced information. The authors investigated whether this bias extended to preferential selection of information to remember, and also examined whether the arousal invoked by stimuli biased item selection and memory. Methods: Thirty older (63–88 years of age) and 30 younger (18–25 years of age) adults viewed emotional (positive, negative) and neutral pictures that varied in arousal (low, high), and were asked to select a subset they deemed memorable (memorability judgments), before recalling pictures. Repeated-measures analyses of variance were conducted to examine aging-related differences in selection and recall of positive, negative, and neutral pictures, and of low- and high-arousal pictures. Results: Older adults selected more positive pictures as memorable, whereas in younger adults selection did not differ by valence. In both age groups, recall of positive pictures was highest. Older adults selected more low- than high-arousal pictures as memorable, although recall was greater for high- than low-arousal pictures in both age groups. Conclusion: Findings are consistent with the view that the aging-related positivity bias is under cognitive control, and suggest an awareness of this in older adults. Future investigations should seek to disentangle the influence of positive valence from other factors (e.g., perceptual, semantic, arousal level) on older adults’ memorability judgments.

The Effects of Valence and Arousal on Associative Working Memory and Long-Term Memory

BackgroundEmotion can either facilitate or impair memory, depending on what, when and how memory is tested and whether the paradigm at hand is administered as a working memory (WM) or a long-term memory (LTM) task. Whereas emotionally arousing single stimuli are more likely to be remembered, memory for the relationship between two or more component parts (i.e., relational memory) appears to be worse in the presence of emotional stimuli, at least in some relational memory tasks. The current study investigated the effects of both valence (neutral vs. positive vs. negative) and arousal (low vs. high) in an inter-item WM binding and LTM task.Methodology/Principal FindingsA five-pair delayed-match-to-sample (WM) task was administered. In each trial, study pairs consisted of one neutral picture and a second picture of which the emotional qualities (valence and arousal levels) were manipulated. These pairs had to be remembered across a delay interval of 10 seconds. This was followed by a probe phase in which five pairs were tested. After completion of this task, an unexpected single item LTM task as well as an LTM task for the pairs was assessed. As expected, emotional arousal impaired WM processing. This was reflected in lower accuracy for pairs consisting of high-arousal pictures compared to pairs with low-arousal pictures. A similar effect was found for the associative LTM task. However, the arousal effect was modulated by affective valence for the WM but not the LTM task; pairs with low-arousal negative pictures were not processed as well in the WM task. No significant differences were found for the single-item LTM task.Conclusions/SignificanceThe present study provides additional evidence that processes during initial perception/encoding and post-encoding processes, the time interval between study and test and the interaction between valence and arousal might modulate the effects of “emotion” on associative memory.

Atypical modulation of cognitive control by arousal in autism

We examined the effects of viewing high-arousal pictures on regional brain activations elicited by a cognitive control task in participants with high-functioning autism and neurotypical controls. Specifically, using event-related functional magnetic resonance imaging, we assessed the effects of brief presentations of highly arousing pictures (i.e., both very pleasant and very unpleasant) on the processing of stimuli requiring cognitive control. Similar to previous findings, when stimuli with high cognitive control demands were preceded by low-arousal pictures, individuals with autism demonstrated regional brain activations that were comparable to neurotypical control individuals. When the presentation of the cognitive control stimuli was preceded by high-arousal pictures, however, the control group was characterized by relatively greater activation in the right lateral midfrontal cortex in response to cognitive control stimuli. In contrast, preceding high-arousal stimuli did not modulate activity elicited in this region by cognitive control stimuli in the autism group. Differential modulation of right lateral midfrontal activation by high-arousal stimuli in autism is consistent with the “inefficiency model” of brain functioning in autism spectrum disorders, and contributes to a growing body of evidence that autism may be characterized by anomalous sensitivity of cognitive control brain regions to social-emotional context.

Do emotional stimuli interfere with response inhibition? Evidence from the stop signal paradigm

Participants performed a stop signal task in which an emotional picture preceded a neutral stimulus. They were asked to respond on the basis of the identity of the neutral stimulus unless an auditory tone was presented, in which case participants should try to withhold their response. In Experiment 1, we used positive, neutral and negative pictures. Results demonstrated that the presentation of an emotional stimulus prolonged both response and stopping latencies regardless of the valence of the emotional stimulus. This suggested that the degree of arousal could modulate the interference effect. In Experiment 2, high- and low-arousing pictures with a positive or negative valence were used. In line with the arousal hypothesis, high-arousal pictures interfered more with responding and stopping than low-arousing pictures whereas the valence of the pictures had little or no effect. These findings support the hypothesis that emotional stimuli interrupt ongoing cognitively controlled activities because they attract attention away from these ongoing activities.