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Fernandez-Folgueiras, U.

Publications and source records attributed to Fernandez-Folgueiras, U..

6 recordsLinked to original sources

An integrated biobehavioral study of empathy

Empathy, a crucial prosocial human trait, is mainly measured through questionnaires, but performance in tasks involving emotional stimuli, brain activity during these tasks, and genetic information also provide relevant clues. These approaches are developed separately or by combining only some of these factors. Integrating them into a single study and analysis may help to better characterize their relative load and to understand the complexity of empathy. The IRI empathy scale was administered to 65 participants, who later performed a lexical decision task on emotional words while their performance and event-related potentials (ERPs) were recorded. Three genetic polymorphisms, one in the OXTR gene (SNP rs2254298) and two in the AVPR1a gene (RS1 and RS3 regions), were also analyzed. Generalized linear models revealed that these biobehavioral factors jointly predicted emotional but not cognitive empathy. Reaction times and the amplitude of the LPP component of ERPs in response to emotional words, along with rs2254298 AA/AG genotype, were significantly associated with scores on the IRI personal distress subscale. Meanwhile, LPP amplitudes and AVPR1a-RS1 LL genotype significantly predicted scores on the empathy concern subscale. The balanced loading of all these factors in the models reinforces the desirability of a comprehensive, multifaceted approach to characterizing empathy.

neuroscience↗

INFLUENCE OF PREMENSTRUAL SYNDROME ON ATTENTIONAL CAPTURE BY EXPRESSIONS IN THE LUTEAL PHASE

Research on female health has increased thanks to the growing interest in womens well-being. Premenstrual Syndrome (PMS) is characterized by its high incidence and negative emotional symptoms during the luteal phase. While various studies suggest that the menstrual cycle affects emotional processing, the role of PMS has barely been investigated. Prior evidence suggests that the menstrual cycle does not modulate the attentional capture by emotional faces (Alvarez et al., 2022). This study aims to explore PMSs impact on this phenomenon. Forty-seven women performed an attentional capture task in both phases of the menstrual cycle, with emotional faces as distractors. Both behavioral performance and Event-Related Potentials (ERPs) were recorded. Additionally, premenstrual symptoms were monitored over two menstrual cycles. Results showed no significant interaction effect of PMS, either at the behavioral or ERP levels. However, emotional stimuli, particularly angry faces, consistently captured attention more than neutral ones, as reflected in enhanced P1 and N170 components. These results indicate no evidence that PMS modulates exogenous attention to emotional stimuli. Future studies should consider individual affective states, such as depressive and anxiety symptoms associated with PMS, rather than PMS as a category, to further investigate the potential effects of PMS on attentional capture.

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Emotional Distractors Capture Attention even at Very Low Contrast Levels: ERP evidence

Emotional visual stimuli, whether appealing or aversive, preferentially capture exogenous attention due to their evolutionary significance. This study assessed whether such capacity persists at low contrast levels, where stimuli are minimally perceived. To this end, we recorded behavioral and electrophysiological (event-related potentials, ERPs) indices of attentional capture from 38 participants who were exposed to negative, neutral, and positive scenes, each presented at four distinct contrast levels. These contrast levels had previously resulted in a correct recognition rate of up to 25%, 50%, 75%, and 100% in a previous sample of 235 participants. Participants were presented with these scenes as distractors while simultaneously performing a perceptual task involving line orientation discrimination. The ERP results confirmed the expected emotional effect on exogenous attention and, critically, unveiled its persistence across all contrast levels. Specifically, occipito-parietal P1 (88-119 ms) was larger for negative than for positive distractors, while in a spreaded N2 component, positive distractors elicited larger amplitudes relative to both negative (213-354 ms) and neutral (213-525 ms) images. These findings reinforce the advantage of emotional distractors in accessing neural processing automatically and highlight the existence of a temporal negativity bias. Importantly, our novel findings emphasize the robustness of this exogenous attention pattern, present even under limited perceptual conditions.

neuroscience↗

An extremely fast neural mechanism to detect emotional visual stimuli: A two-experiment study

Defining the brain mechanisms underlying initial emotional evaluation is a key but unexplored clue to understand affective processing. Event-related potentials (ERPs), especially suited for investigating this issue, were recorded in two experiments (n=36 and n=35). We presented emotionally negative (spiders) and neutral (wheels) silhouettes homogenized regarding their visual parameters. In Experiment 1, stimuli appeared at fixation or in the periphery (200 trials per condition and location), the former eliciting a N40 (39 milliseconds) and a P80 (or C1: 80 milliseconds) component, and the latter only a P80. In Experiment 2, stimuli were presented only at fixation (500 trials per condition). Again, a N40 (45 milliseconds) was observed, followed by a P100 (or P1: 105 milliseconds). Analyses revealed significantly greater N40-C1P1 peak-to-peak amplitudes for spiders in both experiments, and ANCOVAs showed that these effects were not explained by C1P1 alone, but that processes underlying N40 significantly contributed. Source analyses pointed to V1 as a N40 focus (more clearly in Experiment 2). Sources for C1P1 included V1 (P80) and V2/LOC (P80 and P100). These results and their timing point to low-order structures (such as visual thalamic nuclei or superior colliculi) or the visual cortex itself, as candidates for initial evaluation structures.

neuroscience↗

Menstrual cycle and exogenous attention toward emotional expressions

Several studies suggest that the menstrual cycle affects emotional processing. However, these results may be biased by including women with premenstrual syndrome (PMS) in the samples. PMS is characterized by negative emotional symptomatology, such as depression and/or anxiety, during the luteal phase. This study aimed to explore the modulation of exogenous attention to emotional facial expressions as a function of the menstrual cycle in women without PMS. For this purpose, 55 women were selected (from an original volunteer sample of 790) according to rigorous exclusion criteria. Happy, angry, and neutral faces were presented as distractors, while both behavioral performance in a perceptual task and event-related potentials (ERPs) were recorded. This task was applied during both phases of the menstrual cycle (luteal and follicular, counterbalanced), and premenstrual symptomatology was monitored daily. Traditional and Bayesian ANOVAs on behavioral data (reaction times and errors in the task) and ERP indices (P1, N170, N2, and LPP amplitudes) confirmed the expected lack of an interaction of phase and emotion. Taken together, these results indicate that women free of PMS present steady exogenous attention levels to emotionally positive and negative stimuli regardless of the menstrual phase.

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Fast unconscious processing of emotional stimuli in early stages of the visual cortex

Several cortical and subcortical brain areas have been reported to be sensitive to the emotional content of subliminal stimuli. However, the timing of these activations remains unclear. Our scope was to detect the earliest cortical traces of visual unconscious processing by recording event-related potentials (ERPs) from 43 participants. Subliminal spiders (emotional) and wheels (neutral), sharing similar low-level visual parameters, were presented at two different locations (fixation and periphery). The differential (peak to peak) amplitude from CP1 (77 milliseconds from stimulus onset) to C2 (100 milliseconds), two early visual ERP components originated in V1/V2 according to source localization analyses, was analyzed via Bayesian and traditional analyses. Spiders elicited greater CP1-C2 amplitudes than wheels when presented at fixation. This fast effect of subliminal stimulation -not reported previously to the best of our knowledge-has implications in several debates: i) the amygdala cannot be mediating these effects, ii) latency of other evaluative structures recently proposed, such as the visual thalamus, is compatible with these results, iii) the absence of peripheral stimuli effects points to a relevant role of the parvocellular visual system in unconscious processing.

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