Event-related potentials related to normal and morphed emotional faces

S. Bentin and L. Y. Deouell (2000) have suggested that face recognition is achieved through a special-purpose neural mechanism, and its existence can be identified by a specific event-related potential (ERP) correlate, the N170 effect. In the present study, the authors explored the structural significance of N170 by comparing normal vs. morphed stimuli. They used a morphing procedure that allows a fine modification of some perceptual details (first-order relations). The authors also aimed to verify the independence of face identification from other cognitive mechanisms, such as comprehension of emotional facial expressions, by applying an emotion-by-emotion analysis to examine the emotional effect on N170 ERP variation. They analyzed the peak amplitude and latency variables in the temporal window of 120-180 ms. The ERP correlate showed a classic N170 ERP effect, more negative and more posteriorly distributed for morphed faces compared with normal faces. In addition, they found a lateralization effect, with a greater right-side distribution of the N170, but not directly correlated to the morphed or normal conditions. Two cognitive codes, structural and expression, are discussed, and the results are compared with the multilevel model proposed by V. Bruce and A. W. Young (1986, 1998).     

An ERP study on facial expression of emotion: comparison of linguistic and visual semantic decoding

The present research compared the semantic information processing of linguistic stimuli with semantic elaboration of nonlinguistic facial stimuli. To explore brain potentials (ERPs, event-related potentials) related to decoding facial expressions and the effect of semantic valence of the stimulus, we analyzed data for 20 normal subjects (M age = 23.6 yr., SD = 0.2). Faces with three basic emotional expressions (fear, happiness, and sadness from the 1976 Ekman and Friesen database), with three semantically anomalous expressions (with respect to their emotional content), and the neutral stimuli (face without an emotional content) were presented in a random order. Differences in peak amplitude of ERP were observed later for anomalous expressions compared with congruous expressions. In fact, the results demonstrated that the emotional anomalous faces elicited a higher negative peak at about 360 msec., distributed mainly over the posterior sites. The observed electrophysiological activity may represent specific cognitive processing underlying the comprehension of facial expressions in detection of semantic anomaly. The evidence is in favour of comparability of this negative deflection with the N400 ERP effect elicited by linguistic anomalies.     

Morphed facial expressions elicited a N400 ERP effect: A domain‐specific semantic module?

Previous studies have revealed that decoding of facial expressions is a specific component of face comprehension and that semantic information might be processed separately from the basic stage of face perception. In order to explore event-related potentials (ERPs) related to recognition of facial expressions and the effect of the semantic content of the stimulus, we analyzed 20 normal subjects. Faces with three prototypical emotional expressions (fear, happiness, and sadness) and with three morphed expressions were presented in random order. The neutral stimuli represented the control condition. Whereas ERP profiles were similar with respect to an early negative ERP (N170), differences in peak amplitude were observed later between incongruous (morphed) expressions and congruous (prototypical) ones. In fact, the results demonstrated that the emotional morphed faces elicited a negative peak at about 360 ms, mainly distributed over the posterior site. The electrophysiological activity observed may represent a specific cognitive process underlying decoding of facial expressions in case of semantic anomaly detection. The evidence is in favor of the similarity of this negative deflection with the N400 ERP effect elicited in linguistic tasks. A domain-specific semantic module is proposed to explain these results.     

Family Affluence, School and Neighborhood Contexts and Adolescents’ Civic Engagement: A Cross-National Study

Research on youth civic engagement focuses on individual-level predictors. We examined individual- and school-level characteristics, including family affluence, democratic school social climate and perceived neighborhood social capital, in their relation to civic engagement of 15-year-old students. Data were taken from the 2006 World Health Organization Health Behaviour in School-aged Children survey. A sample of 8,077 adolescents in 10th grade from five countries (Belgium, Canada, Italy, Romania, England) were assessed. Multilevel models were analyzed for each country and across the entire sample. Results showed that family affluence, democratic school climate and perceived neighborhood social capital positively related to participation in community organizations. These links were stronger at the aggregate contextual than individual level and varied by country. Canadian youth participated most and Romanian youth least of the five countries. Gender predicted engagement in two countries (girls participate more in Canada, boys in Italy). Findings showed significant contributions of the social environment to adolescents' engagement in their communities.     

Differences in cortical activity related to motor planning between experienced guitarists and non-musicians during guitar playing

The influence of motor skill learning on movement-related brain activity was investigated using electroencephalography. Previous research has indicated that experienced performers display movement-related cortical potentials (MRCPs) of smaller amplitude and later onset compared to novices. Unfortunately, previous studies have lacked ecological validity with experimenters recording the MRCP prior to simple motor tasks and applying the results to more complex motor skills. This study replicated previous research using an ecologically valid motor skill; recording the MRCP from a group of experienced guitarists and a control group of non-musicians while they played a simple scale on the guitar. Results indicated no difference between groups in early motor planning. In contrast, the later, negative slope and motor potential components were of smaller amplitude and the negative slope began later in the experienced guitarists. The data may indicate that, for experienced guitarists, a reduced level of effort is required during the motor preparation phase of the task. These findings have implications for musical instrument learning as well as motor skill acquisition in general.     

rTMS stimulation on left DLPFC increases the correct recognition of memories for emotional target and distractor words

According to a recent hypothesis, the prefrontal cortex has been proposed as the site of emotional memory integration, because it is sensitive to the recognition of emotional contents. In the present research, we explored the role of the dorsolateral prefrontal cortex (DLPFC) in memory recognition processes for positive versus negative emotional stimuli when old (target) and new (distractor, either semantically related or unrelated to the target) stimuli were presented. The role of the DLPFC was analysed using an rTMS (repeated transcranial magnetic stimulation) paradigm that induced increased cortical activation of the left DLPFC. The subjects were required to perform a task that consisted of two experimental phases (i.e., an encoding and a recognition phase) in which the targets and the distractors were presented and recognition performance was measured. rTMS stimulation was provided over the left DLPFC during the recognition phase. We found that the rTMS stimulation affected the memory recognition of positive emotional material. Moreover, related and unrelated distractors were discarded better when they were positively valenced, and a more significant effect (i.e., increased performance) was produced in response to related distractors. This result suggests that the activation of the left DLPFC favours the memory recognition of positive emotional information, and that such activation is able to induce a more appropriate selective process to distinguish target from distractor stimuli in the presence of more complex processes (related distractors). The valence model of emotional cue processing may explain this increased performance by demonstrating the distinct role of the left hemisphere in the retrieval of positive emotional information.     

Motor resources in peripersonal space are intrinsic to spatial encoding: Evidence from motor interference

The aim of this study was to explore the role of motor resources in peripersonal space encoding: are they intrinsic to spatial processes or due to action potentiality of objects? To answer this question, we disentangled the effects of motor resources on object manipulability and spatial processing in peripersonal and extrapersonal spaces. Participants had to localize manipulable and non-manipulable 3-D stimuli presented within peripersonal or extrapersonal spaces of an immersive virtual reality scenario. To assess the contribution of motor resources to the spatial task a motor interference paradigm was used. In Experiment 1, localization judgments were provided with the left hand while the right dominant arm could be free or blocked. Results showed that participants were faster and more accurate in localizing both manipulable and non-manipulable stimuli in peripersonal space with their arms free. On the other hand, in extrapersonal space there was no significant effect of motor interference. Experiment 2 replicated these results by using alternatively both hands to give the response and controlling the possible effect of the orientation of object handles. Overall, the pattern of results suggests that the encoding of peripersonal space involves motor processes per se, and not because of the presence of manipulable stimuli. It is argued that this motor grounding reflects the adaptive need of anticipating what may happen near the body and preparing to react in time.     

Factor Validity of the Beck Hopelessness Scale in Italian Medical Patients

The aim of the present study was to assess the factor structure of the Italian version of the Beck Hopelessness Scale (BHS) in a large sample of patients with medical conditions, comparing four different models proposed previously in the literature. Participants were 514 Italian adult patients with diagnoses of chronic daily headache, type 1 (insulin-dependent) or type 2 diabetes mellitus, epilepsy, open-angle glaucoma, human immunodeficiency virus infection, and women admitted for childbirth to a Department of Fetal–Maternal Medicine. All the patients were administered the BHS during routine visits. Confirmatory factor analyses were used to compare four models using several fit indices. The one-construct two-method model (i.e., the BHS measures one substantive hopelessness construct plus artifacts due to negative–positive item polarity) had the best fit indices and was more parsimonious than other models. The BHS seems to be a unidimensional measure of hopelessness, although there may be artifacts due to item polarity (i.e., positively and negatively worded items). Hopelessness scores differed in patients with particular medical diseases, with higher scores in conditions such as chronic daily headache and diabetes, and lower scores in patients positive for the human immunodeficiency virus (HIV), and with open-angle glaucoma or epilepsy.     

A New Set of Moral Dilemmas: Norms for Moral Acceptability,Decision Times,and Emotional Salience

At the present time, the growing interest in the topic of moral judgment highlights the widespread need for a standardized set of experimental stimuli. We provide normative data for a sample of 120 undergraduate students using a new set of 60 moral dilemmas that might be employed in future studies according to specific research needs. Thirty dilemmas were structured to be similar to the Footbridge dilemma (“instrumental” dilemmas, in which the death of one person is a means to save more people), and thirty dilemmas were designed to be similar to the Trolley dilemma (“incidental” dilemmas, in which the death of one person is a foreseen but unintended consequence of the action aimed at saving more people). Besides type of dilemma, risk‐involvement was also manipulated: the main character's life was at risk in half of the instrumental dilemmas and in half of the incidental dilemmas. We provide normative values for the following variables: (i) rates of participants' responses (yes/no) to the proposed resolution; (ii) decision times; (iii) ratings of moral acceptability; and (iv) ratings of emotional valence (pleasantness/unpleasantness) and arousal (activation/calm) experienced during decision making. For most of the dependent variables investigated, we observed significant main effects of type of dilemma and risk‐involvement in both subject and item analyses. Copyright © 2013 John Wiley & Sons, Ltd.