Psychophysiology最新文献

Access to social support during emotional stress is one of the most important factors for the successful regulation of stress-induced psychophysiological activation, and is predictive of improved health and well-being. In this research we wanted to deepen our understanding of this buffering effect, focusing on the modulation of the startle reflex during a standardized stress induction as a function of the proximity with social resources as well as the relationship type with them. Seventy participants were exposed to the Trier Social Stress Test (TSST) in one of three possible conditions: Alone, Together with their romantic partner, or Together with a stranger. Startle reactivity to a series of acoustic probes presented during the task was measured along with self-reported levels of anxiety. Results indicate that, independently of the social manipulation, stress induction is associated with a strong inhibition of the startle reflex. Furthermore, we found that access to social resources buffers this startle inhibition, showing that being together with others when facing a stressor regulates threat vigilance. We interpret these findings through the lens of the Social Baseline Theory, suggesting that startle dynamically tracks the load sharing process by which proximity with social resources optimizes the physiological as well as cognitive regulation of behavior in a threatening environment.

Although the N170 component is popularly regarded as a marker of configural face processing, contradictory evidence exists. Many neural adaptation studies employing upright and inverted faces as adaptor and test stimuli have reported N170 adaptation effects (i.e., amplitude reduction when preceded by the same versus different face orientation) for inverted but not upright faces, suggesting N170's sensitivity to featural rather than configural processing. Noting that most prior studies relied on non-face-related tasks, the present study systematically investigated N170 adaptation effects under different tasks. Consistent with previous findings, we did not observe a significant adaptation effect for upright faces during a non-face task (flower detection), but such effects emerged in tasks requiring active face discrimination (repeated or target face detection). By contrast, adaptation effects for inverted faces were present regardless of task. Notably, all adaptation effects persisted despite changes in face identity, image, or size, and consistently exhibited the typical right occipito-temporal distribution associated with face processing, indicating they are not attributable to low-level visual adaptation. Further analysis revealed that the N170 adaptation effect for upright faces was influenced by variation in face image but not size, with strongest effects observed when consecutive faces shared the same identity and photograph, an effect absent for inverted faces. Together, our findings suggest that distinct neuronal populations underlie the N170: those more sensitive to inverted faces may process salient facial features (e.g., eyes), while those tuned to upright faces are engaged in configural processing and high-level analysis of facial image patterns.

The amplitude of the error-related negativity (ERN) is known to be correlated with attention to task and general cognitive control abilities. However, previous research has struggled to consistently link ERN amplitude with behavioral accuracy or reaction time in the task from which the ERN is being measured. This lack of relationship could be due to many factors that are difficult to control for, so explorations of other converging measures to understand error-processing and subsequent behavior adjustment are warranted. The current study examines how two other physiological markers of error-processing-the phasic pupillary dilation response (PDR) and the positivity following an error (Pe)-relate to post-error behavior. Additionally, we also examine relationships between the three physiological indices of error-processing. In the study, EEG and pupillometry were simultaneously recorded while participants completed 24 blocks (50 trials each) of an Ericksen Flanker task. For post-error accuracy, we found that on a single-trial level, the amplitude of all three physiological error-processing indices for error trials predicted post-error accuracy. At the subject level, only the PDR predicted average post-error accuracy. For post-error slowing, at the single-trial level, only the Pe predicted post-error slowing, whereas only the ERN predicted post-error slowing at the subject level. We also found that both the ERN and Pe correlated with PDR amplitude. This is consistent with our hypothesis that the Pe and PDR may share underlying neural mechanisms, but qualified by the fact that the ERN, which is not hypothesized to have shared neural mechanisms, also predicted unique variance in pupillary amplitude. Collectively, these results suggest that the PDR and Pe might represent promising indicators of post-error behavior adjustment and highlight the need to examine relationships at multiple levels of analysis.

Alexithymia is a multidimensional construct characterized by difficulties in identifying and describing feelings and reduced ability to engage in abstract thinking. Although often co-occurring with other psychological and neurodevelopmental conditions such as anxiety, depression and autism spectrum disorders, alexithymia is believed to be associated with unique alterations within the socio-emotional brain networks. With the semantic and neuromodulatory brainstem systems playing a key role in social and affective cognition, the current work aimed to study their contributions to alexithymia in unprecedented detail. First, we attempted to identify resting-state functional connectivity patterns of the social semantic hubs (superior anterior temporal lobe) and monoamine-producing regions (dorsal raphe, ventral tegmental area and locus coeruleus) linked to each alexithymia domain. Secondly, by deploying tractography and graph analysis of the associated structural network, we intended to identify their potential anatomical correlates. Alexithymia was strongly associated with dysconnectivity within the semantic network, and altered functional connectivity between the neuromodulatory brainstem regions and cortical areas crucial for social cognition and emotion regulation, including medial prefrontal cortex and inferior parietal lobule. On the anatomical level, these findings were paralleled by negative links with network modularity, suggestive of less specialized neural processing, and decreased clustering coefficient of the semantic node in the left posterior middle temporal gyrus. Despite observing associations with trait-anxiety and emotion suppression for some of the highlighted findings, these phenomena did not mediate the effects of alexithymia. Therefore, the current work highlights the existence of functional and structural alterations within socio-emotional networks as neural markers of alexithymia.

There is growing evidence that electrophysiological markers of selective attention can be reliably assessed at the level of the individual case. The present study extends this work by examining their temporal stability across a one-week retest interval, with a focus on motivated and voluntary attention. Seventeen healthy young adults were tested twice, 1 week apart, using a dense sensor EEG setup. Each session included blocks featuring either highly arousing erotic or mutilation images alongside low-arousing control stimuli. To simultaneously assess voluntary attention, participants performed an emotion categorization task in which high or low arousal images served as targets in separate blocks. Across both emotion categories, the majority of participants showed significant emotional modulation of the EPN (88%) and LPP (100%) components, as well as target P3 effects (76%) in both sessions. Complementary classification approaches based on different significance thresholds further supported the consistency of these effects. Subsampling analyses revealed that although reducing trial numbers diminished reliability, robust effects, particularly for the EPN and LPP in response to erotic stimuli, remained detectable at moderate trial counts. Analyses at the group level revealed excellent test-retest reliabilities for the EPN (ICC > 0.91) and target P3 (ICC > 0.86). While reliability was good for the LPP (ICC > 0.60), the confidence intervals indicated substantial variability. Together, these findings demonstrate that neural correlates of both motivated and voluntary attention exhibit high test-retest reliability at the individual level, reinforcing their utility as biomarkers and highlighting the value of single-case analyses in electrophysiological research.

The aim of our study was to examine the effects of a 6-month school-based high-intensity interval training intervention (Burn 2 Learn [B2L]) on a priori regional brain volumes in adolescents using magnetic resonance imaging (MRI). Participants were older adolescents [N = 56, 61% female, 16.1 ± 0.4 years] from four schools (10 classes) participating in a larger cluster randomized controlled trial. Participants were randomized to B2L (five classes, N = 30) or a control group (five classes, N = 26) and underwent MRI at baseline and 6-month follow-up. Changes in regional gray matter volumes were assessed using linear mixed models adjusted for sex, weight status, intracranial volume, and class level clustering. We observed increases in total (+105.5 mm³, 95% confidence interval [CI] 25.2 to 185.8, d = 0.79) and left (+64.7 mm³, 95% CI 13.8 to 115.7, d = 0.76) hippocampal volume in the B2L group compared to the control group. We also observed that the B2L group retained significantly greater left medial superior frontal gyrus gray matter volume compared to the control group (+144.8 mm³, 95% CI 17.1 to 272.5, d = 0.68). There was a decrease in total (-30.6 mm³, 95% CI -50.9 to -10.2, d = -0.90), left (-15.2 mm³, 95% CI -28.9 to -1.5, d = -0.67), and right (-18.6 mm³, 95% CI -30.8 to -6.4, d = -0.92) nucleus accumbens volume, as well as total (-78.3 mm³, 95% CI -146.8 to -9.9, d = -0.69) and right (-58.7 mm³, 95% CI -99.7 to -17.6, d = 0.86) putamen volume in the B2L group compared to the control group. This is the first experimental study to show that school-based physical activity may play a key role in nurturing the healthy development of cortical and subcortical brain regions associated with cognitive and mental health in adolescents. Larger studies are needed to replicate our findings and confirm the effects of exercise training on brain health in this population.

Poor sleep has been associated with cardiovascular disease (CVD). Research indicates a bidirectional relationship between stress and disrupted sleep. It is possible individual differences in cardiovascular and psychological responses to acute stress may be a pathway connecting sleep and CVD. Research has also separately found biological sex may impact sleep and CVD outcomes. While studies examining subjective sleep and cardiovascular reactivity to acute stress show mixed results, few have concurrently assessed psychological stress responses or considered the moderating role of biological sex. The current paper aimed to explore the associations between subjective sleep quality and cardiovascular and psychological responses to acute stress and the role of biological sex as a potential moderator in this relationship. In two independent studies (Study 1: N = 154, 50.6% female; Study 2: N = 212, 64.2% female), young adults completed a resting baseline period followed by standardized psychological stress tasks with cardiovascular activity measured throughout. Following the stress task, participants rated the intensity and interpretation of their stress during the task. Participants also completed a questionnaire regarding their sleep over the past month. Across both studies, subjective sleep quality was not statistically significantly associated with cardiovascular reactivity (all ps ≥ 0.286, all βs ≤ 0.08). However, worse sleep was significantly associated with increased levels of stress intensity (all ps ≤ 0.023, all βs ≤ 0.22) and more debilitative interpretations of stress during the acute psychological stress task (all ps ≤ 0.020, all βs ≥ -0.25). Biological sex did not moderate any of these relationships (all ps ≥ 0.073). Results indicate that poor subjective sleep quality is associated with psychological, not physiological, responses to stress. Perceptions of stress may be a mechanism linking poor sleep and CVD.

Emotional visual stimuli presented in laboratory settings reliably elicit prototypical patterns of subjective and psychophysiological responses. These responses likely serve distinct functions and reflect the engagement of appetitive and defensive motivational systems, making them a valuable tool for examining emotional processing in both healthy individuals and those with mental disorders. Event-related potentials (ERPs), such as the Cue-P300, Stimulus Preceding Negativity (SPN), and Late Positive Potential (LPP), provide valuable temporal insight into anticipatory and elaborative stages of emotional processing. While these components have been extensively studied using the International Affective Picture System (IAPS), concerns about its dated content have prompted the development of alternative image sets, such as the Open Affective Standardized Image Set (OASIS). Yet, ERP responses to OASIS images remain underexplored. This study aimed to compare psychophysiological and subjective responses elicited by images from the IAPS and OASIS databases, matched for valence and arousal. Twenty-three participants completed two emotional S1-S2 tasks-one using IAPS images and the other using OASIS images-while undergoing EEG recording. In each task, a cue (S1) predicted the valence (pleasant, neutral, unpleasant) of an upcoming emotional image (S2). The SPN, Cue-P300, and the LPP components were analyzed. Results revealed that emotional (pleasant, unpleasant) OASIS images elicited larger Cue-P300 amplitudes than IAPS emotional images, whereas no SPN component was observed for either database. In addition, both IAPS and OASIS images elicited a robust LPP modulation, with this effect more pronounced for IAPS than OASIS unpleasant images. Together, these results indicate that both IAPS and OASIS images elicit the expected emotional responses. Self-reported ratings were similar across the two databases, alongside the LPP modulation by emotional content. Although further research is needed to clarify how image selection may influence emotional anticipation, the integration of the two databases appears to be a future viable approach.

This study was designed to examine the effect of frontal hemispheric asymmetry (FHA) on effort-related cardiovascular responses. High-definition transcranial direct current stimulation (HD-tDCS) was applied to the dorsolateral prefrontal cortex (dlPFC) to manipulate FHA and investigate its impact on cardiovascular reactivity. The sample consisted of 45 female and 44 male participants, who received either left or right cathodal stimulation. Following stimulation, participants performed two types of task demands: one fixed and easy, the other unfixed. In both tasks, participants could earn a moderate monetary reward. We measured pre-ejection period (PEP), heart rate (HR), systolic blood pressure (SBP), and diastolic blood pressure (DBP). Drawing on motivation intensity theory (MIT), we predicted that right cathodal stimulation (left FHA) would lead to higher perceived success importance to get the reward determining higher effort in the unfixed task demand compared to the left cathodal stimulation and both stimulation conditions in the fixed task. As predicted, PEP reactivity was stronger in the unfixed condition following right cathodal stimulation compared to left cathodal stimulation and both stimulation conditions in the fixed task. Importantly, this effect was observed across both female and male participants, extending earlier neuromodulation findings (previously shown only in female samples) to both sexes. Overall, the results indicate that dlPFC neuromodulation can lead to higher effort by shifting frontal asymmetry and enhancing the perceived success importance in reward-driven tasks.

Telemanipulation allows remote operations using specialized tools, often under limited sensory input, such as the absence of haptic feedback. With practice, these tools can become embodied extensions of the user, enhancing Presence. Sensory Substitution, conveying information from one sensory modality through another, can mitigate sensory limitations in such tasks. We developed the Visual-Tactile Sensory Substitution Task to investigate learning of Sensory Substitution while accounting for Embodiment and Presence experience. Forty participants completed a within-subjects repeated-measures design in which each individual was required to manipulate 200 virtual elastic slabs using a haptic stylus to maximize deformation without breakage. Each participant performed two trial types in random order: 50% with force feedback (Control Condition) and 50% without it (Sensory Substitution Condition). Performance metrics included Frequency of Errors, Elapsed Time, Maximal Applied Force, along with Maximal Pupil Dilation and Number of Blinks as workload and learning indicators. Participants also assessed their Perceived Sensory Substitution, Embodiment, and Presence after the task. All metrics were analyzed separately for correct, incorrect, and aggregated trials. Structural Equation Modeling was applied to test the effects of Perceived Sensory Substitution (exogenous variable) on Sensory Substitution Learning via Embodiment and Presence (endogenous variables). Participants in the Sensory Substitution Condition showed reduced Elapsed Time, comparable Maximal Applied Force, and higher Frequency of Errors compared to the Control Condition. Blink rate showed phase-dependent modulation during correct trials, consistent with task learning, while pupil dilation remained stable across phases and feedback conditions. Structural Equation Modeling revealed that Perceived Sensory Substitution positively influenced Embodiment, Presence, and Learning. Overall, Sensory Substitution supports telemanipulation by fostering Embodiment and reducing task time, while modulating sensorimotor learning strategies relevant for efficient remote operation.