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Individual abilities in face recognition (good versus bad recognizers) were explored by means of event-related potentials (ERPs). The adaptation response profile of the N170 component to whole faces, eyes and mouths was used in order to highlight the crucial role of individual abilities in identity repetition processes for unfamiliar faces. The main point of this study is to underline the importance of characterizing the performance (bad or good) of the participants and to show that behaviorally selected groups might reveal neural differences. Good recognizers showed selective right hemisphere N170 repetition effects for whole faces and not for features. On the contrary, bad recognizers showed a general repetition effect not specifically related to faces and more pronounced processing for features. These findings suggest a different contribution of holistic and featural analysis in bad and good performers. In conclusion, we propose that the N170 might be used as a tool to tease apart face encoding processes as a function of individual differences.

In this study, we conducted two experiments to evaluate the effect of different types of odors on a time reproduction task, comparing performances of males to those of females. In the first experiment, subjects had to estimate short (510, 600, 690 ms) and long (1700, 2000, 2300 ms) interval durations under three odor conditions: positive, negative and neutral. A gender specific effect of olfactory stimulation on time estimation was found only for short durations. Namely, females were less accurate (overestimated) in reproducing short time intervals during the unpleasant odor presentation. This effect was confirmed and strengthened in the second experiment in which the intensity of the negative odor was enhanced. The present findings suggest that the neural network underlying time estimation is more “sensitive” to context manipulations in females than in men. Practical Applications The first important point is that there might be relevant gender differences in the processing of time (time estimation) that are mediated by olfactory stimulation. This new evidence might have important implications and applications in health issues and especially in workplace safety, for example in jobs or contexts in which fast processing and rapid decisions or choices are required. Therefore, the knowledge that females are more influenced by unpleasant odors than males during time estimation should be seriously considered in situations in which time plays a crucial role such as during rapid decision-making, where automatic processes should be efficiently activated. Overall, the higher sensitivity to specific olfactory stimulation observed in women probably reflects individual differences in a complex process such as time processing.

La prosopagnosia congenita (Congenital Prosopagnosia: CP) e un deficit di riconoscimento dei volti familiari presente, presumibilmente, fin dalla nascita ed in assenza di danni cerebrali. Nel presente studio 300 soggetti sono stati sottoposti ad un approccio metodologico integrato che ha previsto l’utilizzo di un questionario, appositamente creato per l’autovalutazione della capacita di riconoscimento dei volti e di un test oggettivo, ampiamente utilizzato in letteratura, per fini diagnostici - il Cambridge Face Memory Test (CFMT, Duchaine e Nakayama, 2006). Nella prima fase dello studio, in base al punteggio riportato al questionario di autovalutazione, sono stati selezionati 12 individui potenzialmente prosopagnosici i quali sono stati, successivamente, sottoposti al CFMT. Tre di questi hanno presentato prosopagnosia congenita; questo dato ci ha permesso di stimare un preliminare tasso di prevalenza del deficit nella popolazione italiana. Nella seconda fase dello studio, i tre soggetti prosopagnosici individuati sono stati sottoposti ad una serie di esperimenti comportamentali per esplorare, piu dettagliatamente, quali meccanismi di elaborazione dei volti risultano particolarmente compromessi in presenza di CP. La batteria comprendeva: un compito per testare l’eventuale presenza dell’effetto inversione per i volti, un test di riconoscimento di volti famosi italiani, un compito di elaborazione della familiarita di volti ignoti con il classico paradigma Old-New, due compiti di riconoscimento di altre categorie di stimoli complessi. I risultati hanno mostrato un deficit specifico per i volti, confermato da una debole traccia mnestica; l’assenza del classico effetto inversione potrebbe essere indice di un’alterazione del processo olistico. In conclusione, i risultati riportano per la prima volta la presenza della CP presso la popolazione italiana e suggeriscono l’uso di un approccio metodologico integrato per la selezione del campione clinico per futuri studi presso la popolazione italiana.

The aim of our study was to evaluate the effect of animal-assisted intervention (AAI), a complementary support to traditional therapies focused on the interaction between animals and human beings, in improving psychological trait, anxiety and pain in a cohort of systemic sclerosis (SSc) patients.42 SSc patients, undergoing iloprost intravenous infusion, were divided in three groups: 1) 14 patients submitted to 20 AAI sessions; 2) 14 patients engaged in alternative social activity (control group 1 - C1); and 3) 14 patients without any alternative activity (control group 2 - C2). All patients underwent Visual Analog Scale (VAS), the State-anxiety (STAI-S) and emotional faces at the beginning (s0) and at the end (s1) of each single session, while General Anxiety State-Trait Anxiety Inventory (STAI-T), Beck Depression Inventory (BDI), Social Interaction Anxiety Scale (SIAS), Eysenck Personality Questionnaire-Revised (EPQ-R), the Social Phobia Scale (SPS), the Toronto Alexythymia Scale (TAS-20), the Thought Control Questionnaire (TCQ) were administered at baseline (t0) and at the end of the project (t1).AAI group showed a significant decrease of the anxiety state level in respect to the two control groups (p0.001). VAS scale resulted lower both in AAI (p0.001) and C1 group (p0.01). Moreover, STAI-T and TAS scores were significantly reduced in AAI group (p0.001). TCQ scale showed that patients treated with AAI, compared to control group C2, had greater capacity to avoid unpleasant and unwanted thoughts (p0.05). In AAI group, the EPQ-R test revealed an enhancement of extroversion trait compared to both control groups (p0.05).Our data show that AAI significantly reduces pain perception, anxiety, neuroticism and ameliorates patients' social interaction, therefore it may be a useful to allow a better compliance to traditional therapies.

Objective The aim of this study was to characterize the temporal dynamics of face encoding and recognition as a function of inversion. Methods Event-related potentials (ERPs) were recorded while participants performed a recognition task in which orientation was manipulated both at study and retrieval. This procedure was used to compare the effects of same and different orientation at encoding and retrieval on early and later recognition-related components. Results Changes in orientation from encoding to retrieval led to worse recognition performance, as compared to unchanged face orientations. Changes in face orientation were also associated with longer N170 latencies at retrieval. Later memory related ERP components (>300 ms) were affected by inversion and changes in orientation in a graded manner: upright faces encoded upright yielded the largest old–new effects, followed by inverted faces encoded inverted and finally by faces that differed in orientation from encoding to retrieval. Conclusions These results suggest that the disruption of configural information caused by inversion has different effects on memory depending on whether the face is presented at retrieval with the same orientation as at encoding. Significance These findings show a dynamic interplay between perception and memory in which face orientation interacts with structural encoding and memory.

Alpha waves are traditionally considered a passive consequence of the lack of stimulation of sensory areas. However, recent results have challenged this view by showing a modulation of alpha activity in cortical areas representing unattended information during active tasks. These data have led us to think that alpha waves would support a 'gating function' on sensorial stimulation that actively inhibits unattended information in attentional tasks. Visual suppression occurring during a saccade and blink entails an inhibition of incoming visual information, and it seems to occur at an early processing stage. In this study, we hypothesized that the neural mechanism through which the visual system exerts this inhibition is the active imposition of alpha oscillations in the occipital cortex, which in turn predicts an increment of alpha amplitude during a visual suppression phenomena. We measured visual suppression occurring during short closures of the eyelids, a situation well suited for EEG recordings and stimulated the retinae with an intra-oral light administered through the palate. In the behavioral experiment, detection thresholds were measured with eyes steady open and steady closed, showing a reduction of sensitivity in the latter case. In the EEG recordings performed under identical conditions we found stronger alpha activity with closed eyes. Since the stimulation does not depend on whether the eyes were open or closed, we reasoned that this should be a central effect, probably due to a functional role of alpha oscillation in agreement with the 'gating function' theory.

Facial attractiveness plays a key role in human social and affective behavior. To study the time course of the neural processing of attractiveness and its influence on recognition memory we investigated the event-related potentials (ERPs) elicited in an old/new recognition task in response to faces with a neutral expression that, at encoding, were rated for their attractiveness. Highly attractive faces elicited a specific early positive-going component on frontal sites; in addition, with respect to less attractive faces, they elicited larger later components related to structural encoding and recognition memory. All in all, our results show that facial attractiveness, independently from facial expression, modulates face processing throughout all stages from encoding to retrieval.

International audience; The main goal of present work is to gain new insight into the temporal dynamics underlying the voluntary memory control for neutral faces associated with neutral, positive and negative contexts. A directed forgetting (DF) procedure was used during the recording of EEG to answer the question whether is it possible to forget a face that has been encoded within a particular emotional context. A face-scene phase in which a neutral face was showed in a neutral or emotional scene (positive, negative) was followed by the voluntary memory cue (cue phase) indicating whether the face had to-be remember or to-be-forgotten (TBR and TBF). Memory for faces was then assessed with an old/new recognition task. Behaviorally, we found that it is harder to suppress faces-in-positive-scenes compared to faces-in-negative and neutral-scenes. The temporal information obtained by the ERPs showed: 1) during the face-scene phase, the Late Positive Potential (LPP), which indexes motivated emotional attention, was larger for faces-in-negative-scenes compared to faces-in-neutral-scenes. 2) Remarkably, during the cue phase, ERPs were significantly modulated by the emotional contexts. Faces-in-neutral scenes showed an ERP pattern that has been typically associated to DF effect whereas faces-in-positive-scenes elicited the reverse ERP pattern. Faces-in-negative scenes did not show differences in the DF-related neural activities but larger N1 amplitude for TBF vs. TBR faces may index early attentional deployment. These results support the hypothesis that the pleasantness or unpleasantness of the contexts (through attentional broadening and narrowing mechanisms, respectively) may modulate the effectiveness of intentional memory suppression for neutral information.

A rapid neural adaptation procedure and Event Related Potentials (ERPs) were employed to study individual differences in Good and Bad recognizers in face perception. The major goal was to characterize the sensitivity of the P100 and the N170 to the identity repetition effect as a function of inter-individual perceptual abilities. For these purposes an integrated methodological approach was used in which a self-report, a standardized test and behavioral performances were combined with ERPs measures. Specifically, two groups of face recognizers (Good and Bad recognizers) were selected by means of a self-report questionnaire on face recognition abilities (The Italian Face Abilities Questionnaire) and the scoring at the Cambridge Face Memory Test. The P100 showed an early neural tuning for faces in Good recognizers. The N170 triggered by the adaptor showed face specificity compared to cars but, importantly, only Good recognizers showed a decreased amplitude of N170 for test faces of the same identity compared to test faces of different identity while this was not the case for Bad recognizers. These results show that ERPs are a suitable and sensitive tool to tap individual differences in face recognition. In conclusion, our results show the importance of considering inter-individual different perceptual abilities in face processing research.

The emotional influence of facial expressions on memory is well-known whereas the influence of emotional contextual information on memory for emotional faces is yet to be extensively explored. This study investigated the interplay between facial expression and the emotional surrounding context in affecting both memory for identities (item memory) and memory for associative backgrounds (source memory). At the encoding fearful and happy faces were presented embedded in fear or happy scenes (i.e.: fearful faces in fear-scenes, happy faces in happy-scenes, fearful faces in happy-scenes and happy faces in fear-scenes) and participants were asked to judge the emotional congruency of the face-scene compounds (i.e. fearful faces in fear-scenes and happy faces in happy-scenes were congruent compounds). In the recognition phase, the old faces were intermixed with the new ones: all the faces were presented isolated with a neutral expression. Participants were requested to indicate whether each face had been previously presented (item memory). Then, for each old face the memory for the scene originally compounded with the face was tested by a three alternative forced choice recognition task (source memory). The results evidenced that face identity memory is differently modulated by the valence in congruent face-context compounds with better identity recognition (item memory) for happy faces encoded in happy-scenarios. Moreover, also the memory for the surrounding context (source memory) benefits from the association with a smiling face. Our findings highlight that socially positive signals conveyed by smiling faces may prompt memory for identity and context.

In time processing, the role of different cortical areas is still under investigation. Event-related potentials (ERPs) represent valuable indices of neural timing mechanisms in the millisecond-to-second domain. We used an interference approach by repetitive TMS (rTMS) on ERPs and behavioral performance to investigate the role of different cortical areas in processing basic temporal information. Ten healthy volunteers were requested to decide whether time intervals between two tones (S1-S2, probe interval) were shorter (800 ms), equal to, or longer (1200 ms) than a previously listened 1000-ms interval (target interval) and press different buttons accordingly. This task was performed at the baseline and immediately after a 15-min-long train of 1-Hz rTMS delivered over the supplementary motor area, right posterior parietal cortex, right superior temporal gyrus, or an occipital control area. Task accuracy, reaction time, and ERPs during (contingent negative variation, CNV) and after the presentation of probe intervals were analyzed. At the baseline, CNV amplitude was modulated by the duration of the probe interval. RTMS had no significant effect on behavioral or ERP measures. These preliminary data suggest that stimulated cortical areas are less crucially involved than other brain regions (e.g. subcortical structures) in the explicit discrimination of auditory time intervals in the range of hundreds of milliseconds.

The question that motivated this study was to investigate the relation between trait anxiety, emotions and memory control. To this aim, memory suppression was explored in high and low trait anxiety individuals with the Think/No-think paradigm. After learning associations between neutral words and emotional scenes (negative, positive, and neutral), participants were shown a word and were requested either to think about the associated scene or to block it out from mind. Finally, in a test phase, participants were again shown each word and asked to recall the paired scene. The results show that memory control is influenced by high trait anxiety and emotions. Low trait anxiety individuals showed a memory suppression effect, whereas there was a lack of memory suppression in high trait anxious individuals, especially for emotionally negative scenes. Thus, we suggest that individuals with anxiety may have difficulty exerting cognitive control over memories with a negative valence. These findings provide evidence that memory suppression can be impaired by anxiety thus highlighting the crucial relation between cognitive control, emotions, and individual differences in regulating emotions.

The relation between attractiveness and motor affordance is a key topic in design and has not yet been investigated electrophysiologically. In this respect, action affordance and attractiveness represent two crucial dimensions in object processing (specifically for tools). In light of this evidence, Event Related Potentials (ERPs) enabled us to gain new insights into the time course of the interaction between these two dimensions during an explicit tool evaluation task. Behaviorally, tools that were judged as high affording and high attractive yielded faster response times than those judged as low affording and low attractive. The ERP results showed that early processes related to sensory gating and feature extraction (N100) were sensitive to both affordance and attractiveness; the P200 was dominated by affordance, indexing a facilitated access to motor action representation. The N300, P300 and the Late Positive Potential (LPP) showed enhanced responses for highly affording/attractive tools, reflecting the interconnection between attractiveness and affordance. Later responses were entirely affected by attractiveness, suggesting additional affective responses evoked by desirable tools. We are showing that things that are perceived as more functional and attractive have a privileged neural activation in the time course of tool evaluation, for the first time.

Background “Pet Therapy”, better defined as Animal-assisted Intervention (AAI), is based on the interaction between animal and human being and is a tool which may complement and support traditional therapies. It can be used on patients affected by different diseases, improving their quality of life from behavioral, physical and psychosocial point of view. Objectives The aim of our study was to evaluate the effect of AAI in improving quality of life and compliance to standard pharmacological treatment in a cohort of Systemic Sclerosis (SSc) patients. Methods 42 SSc patients attending at Scleroderma Unit and undergoing iloprost intravenous infusion were divided in three groups: 1) 14 SSc patients (mean age 60.4±8.6 yrs) submitted to 20 AAI sessions with a professional team (doctor, nurse, couple of animal-handler); 2)control (C1) 14 SSc patients (mean age 63.4±5.3 yrs) engaged in alternative social activity as create a cookbook; 3)control (C0) 14 SSc patients (mean age 62.3±6.8 yrs) without any alternative activity. All patients underwent psychological evaluation at baseline (t0) and at the end of project of AAI (t1); moreover the following test (italian standardized version) was performed at the beginning (s0) and at the end (s1) of each single session: General Anxiety State-Trait Anxiety Inventory (STAI-T), Beck Depression Inventory (BDI), Social Interaction Anxiety Scale (SIAS), Eysenck Personality Questionnaire-Revised (EPQ-R), the Social Phobia Scale (SPS), the Toronto Alexythymia Scale (TAS-20), the Thought Control Questionnaire (TCQ), the Visual Analog Scale (VAS), the State-anxiety (STAI-S). Results At the end of each session, AAI group showed a decrease of the anxiety state level while it was higher in the two control groups ( p s p s Conclusions In agreement with literature [1], our work showed that AAI might be a crucial tool to support the traditional therapies thanks to the creation of a different relationship between patient and doctor. This may allow a better compliance to the therapy in a chronic disease like SSc, where patient9s compliance is usually low. References Matuszek S. Animal-facilitated therapy in various patient populations: systematic literature review. Holist Nurs Pract. 2010 Jul-Aug;24(4):187–203. Disclosure of Interest None declared

The aim of the present study was to uncover the temporal dynamics of face recognition as a function of reward. Event-related potentials (ERPs) were recorded during the encoding and the subsequent old/new memory test in response to faces that could be associated with a monetary reward. The behavioral results showed that faces associated with reward at both encoding and retrieval were recognized better than the unrewarded ones. ERP responses highlighted that successful encoding predictive of subsequent memory was greater for faces associated with reward than for faces without reward-driven motivational learning. At retrieval, an early positive-going component was elicited for potentially rewarded faces on frontal regions, while the occipito-temporal N170 component showed priming effects as a function of reward. Later on, larger centro-parietal ERP components, related to recognition memory, were found selectively for reward-associated faces. Remarkably, electrophysiological responses varied in a graded manner, with the largest amplitude yielded by faces with double reward, followed by faces associated with reward only at encoding. Taken together, the present data show that the processing of outcome expectations affects face structural encoding and increases memory efficiency, yielding a robust and sustained modulation over frontal and temporal areas where reward and memory mechanisms operate in conjunction.

Facial expressions play a key role in affective and social behavior. However, the temporal dynamics of the brain responses to emotional faces remain still unclear, in particular an open question is at what stage of face processing expressions might influence encoding and recognition memory. To try and answer this question we recorded the event-related potentials (ERPs) elicited in an old/new recognition task. A novel aspect of the present design was that whereas faces were presented during the study phase with either a happy, fearful or neutral expression, they were always neutral during the memory retrieval task. The ERP results showed three main findings: An enhanced early fronto-central positivity for faces encoded as fearful, both during the study and the retrieval phase. During encoding subsequent memory (Dm effect) was influenced by emotion. At retrieval the early components P100 and N170 were modulated by the emotional expression of the face at the encoding phase. Finally, the later ERP components related to recognition memory were modulated by the previously encoded facial expressions. Overall, these results suggest that face recognition is modulated by top-down influences from brain areas associated with emotional memory, enhancing encoding and retrieval in particular for fearful emotional expressions.

Previous studies indicate that extinguished stimuli can still be unconsciously processed, leading to implicit priming effects. Here we investigated whether these implicit effects might be modulated by the semantic nature of the stimuli. Five neglect patients and ten controls performed an identification task of items belonging to living and non-living categories. In the study phase photographs of animals and artifacts were presented either to the left visual field (LVF) or to the right visual field (RVF). In the identification phase, each stimulus was displayed centrally and was revealed in a sequence of frames where the item was represented by an increasingly less and less filtered image up to a complete version. The results showed that lateralized stimuli differentially affected controls’ and neglect patients’ memory retrieval. In controls memory traces from the study phase served as efficient primes, thereby reducing the amount of information necessary for the identification of both stimulus categories. Moreover, hemispheric differences emerged with an advantage of the RVF/left hemisphere for artifact items, while no difference was found for living things. Neglect patients showed a priming effect for artifact items presented either to the RVF/left hemisphere or LVF/right hemisphere, as well as for living items presented to the RVF/left hemisphere, but not for living items presented to the LVF/right hemisphere. The priming effect observed for extinguished artifacts is consistent with the evidence of the existence of a specific mechanism destined to analyze, in an automatic and implicit fashion, motor-relevant information of manipulable objects and tools, which are important for identification process. Results are discussed in relation to current models of organization of conceptual knowledge within the framework of different processes performed by the two hemispheres.

Event related potentials (ERPs) were employed to investigate whether and when brain activity related to face recognition varies according to the processing level undertaken at encoding. Recognition was assessed when preceded by a "shallow" (orientation judgement) or by a "deep" study task (occupation judgement). Moreover, we included a further manipulation by presenting at encoding faces either in the upright or inverted orientation. As expected, deeply encoded faces were recognized more accurately and more quickly with respect to shallowly encoded faces. The ERP showed three main findings: i) as witnessed by more positive-going potentials for deeply encoded faces, at early and later processing stage, face recognition was influenced by the processing strategy adopted during encoding; ii) structural encoding, indexed by the N170, turned out to be "cognitively penetrable" showing repetition priming effects for deeply encoded faces; iii) face inversion, by disrupting configural processing during encoding, influenced memory related processes for deeply encoded faces and impaired the recognition of faces shallowly processed. The present study adds weight to the concept that the depth of processing during memory encoding affects retrieval. We found that successful retrieval following deep encoding involved both familiarity- and recollection-related processes showing from 500 ms a fronto-parietal distribution, whereas shallow encoding affected only earlier processing stages reflecting perceptual priming.

Background Recently, the affective relationship between humans and animals has shown a potentially beneficial effects in clinical domains. However, the claim of different studies of the benefits of animal-assisted activities (AAA) is still lacking evidence base data. Objectives To gain insights into the effectiveness of AAA, physiotherapy and psychological support in SSc. Methods 12 SSc female patients (mean age of 60.52±8.3) were treated once a week by a team made of a dog-handler a rheumatologist and a psychologist. They underwent 10 dog-assisted interventions. At onset and after 3 months, the questionnaires and self reports were completed: pain evaluation (VAS 0-100), emotional and affective evaluation (Happy Face-Sad Face Scale), state anxiety (STAI), and a specific designed self report on the liking and satisfaction of the AAA interventions (AAA-Q). Results Significant improvements were reported for pain perception, mood, and other measures of distress among patients after AAA. Pain decreased significantly (p 76±7.5 vs 62±4.3) significantly different before and after AAA (p Conclusions This is the first study measuring the efficacy of AAA (with dogs) on the physiological, emotional, social well-being and pain perception in SSc. The study provides the evidence for pain control with enhancement of the psychosocial well-being. AAA integrated with the traditional medical approach may provide a good support for SSc patients. Disclosure of Interest None declared

In order to tap the electrophysiological correlates of the perceptual and structural encoding stages of face processing, we investigated how inversion and familiarity affect the face-specific event-related potentials (ERPs) components. ERPs were recorded while participants performed a familiarity judgment task with upright and inverted photographs of famous and unknown faces. The early P100 component was found to be sensitive to facial configuration that is disrupted by face inversion. Noteworthy, in addition to the ongoing effect of orientation, an effect of familiarity, although limited to upright faces, emerged at the processing stage indexed by N170. Later on, as witnessed by the P250 component, the familiarity effect was generalized to both upright and inverted faces with a larger amplitude for inverted famous faces. All in all, the present results suggest that the face structural encoding stage is cognitively permeable by higher-order factors such as familiarity, especially when familiarity is crucial for mastering the task. From a more general viewpoint, these results indicate that face processing is subserved by multiple mechanisms in which structural (i.e. orientation) and semantic (i.e. familiarity) factors begin to interact at early processing stages with different time courses. The electrophysiological correlates of these mechanisms are documented by the differential involvement of the major ERP components in the "familiarity check". With upright faces familiarity affects the N170 component, while with inverted faces it affects later components, in keeping with a prolonged time course of the familiarity decision when orientation is not upright.

The aim of the current study was to investigate the electrophysiological correlates of face processing in different groups of subjects selected on the basis of their poor, low or high face ability, namely Congenital Prosopagnosics, Bad and Good face recognizers. We examined how the Event Related Potentials (ERP) components were modulated by individual differences. The study was characterized by two sessions, in the first session face ability was evaluated by means of two tests: the Cambridge Face Memory Test and the Cambridge Face Perception Test. Subjects whose scores fell within two and one SDs below the mean were classified as Congenital Prosopagnosics and Bad recognizers respectively; whereas those that fell within one SD above the mean were classified as Good recognizers. In the second session, ERP were recorded during a same/different task with the procedure of the neural rapid visual adaptation. A modulation of neural activity emerged as function of individual differences. Specifically, the N170 component – a face-specific neural marker – showed an adaptation pattern according to different groups. Amplitude and latency varied as function of face ability showed by subjects, indicating a specific brain activity linked to individual differences in face processing.

The ability to encode together emotional attributes and face identity has a key role in human interactions. Several neuroimaging studies investigated the emotional stimuli encoding but a still open question is the temporal dynamic of the interaction between emotion and memory. We used ERPs with the major goal to investigate whether and when the emotional processing effectiveness drives the encoding. Emotional processing (Early frontal positivity) and subsequent memory (Dm effect) was investigated for faces with either happy, fearful or neutral expressions at encoding. At retrieval all faces were presented with neutral expression and participants were to judge old and new faces. ERP results showed a very early interaction between emotion and successful encoding of faces. Furthermore, the Dm amplitude was modulated as a function of the emotional attributes of the stimuli. All in all, our data suggest that the emotional processing influence encoding through two distinct mechanisms. At an early latency, the effectiveness of salience-related processing may benefit memory in a nonspecific way, while later on a valence-related facilitation may enhance memory formation, particularly for fearful faces.

Objective Time processing in the millisecond-to-minute range is reflected by Event-Related Potentials (ERPs), but the neural circuits of timing remains controversial. In the present study we investigated the role of different cortical areas in the processing of basic temporal information using an interference approach with repetitive transcranial magnetic stimulation (rTMS) and ERPs as indices of timing mechanisms. Methods Nine healthy volunteers performed a temporal discrimination task in which they had to decide whether the time interval between two tones was shorter (800 ms), equal to, or longer (1200 ms) than a previously listened standard interval (1000 ms) and press different buttons accordingly. The task was performed at the baseline and immediately after a 15-min-long train of focal 1-Hz rTMS delivered to supplementary motor area, right posterior parietal cortex, right superior temporal gyrus, or Oz (control area). Accuracy and reaction times and ERPs during (contingent negative variation, CNV) and after the end of the comparison interval were analyzed. Results At the baseline, CNV was modulated by the interval duration and the analysis of the ERP evoked after the end of the comparison interval showed that the amplitude of the positive peak emerging approximately after 200 ms was higher for ‘Long’ compared to ‘Short’ intervals, whereas amplitude for ‘Equal’ was intermediate. RTMS interference had no significant effect on behavioural performance or ERP components. Conclusion These data may suggest that these cortical areas are less crucially involved than other brain regions (e.g. sub-cortical or cerebellar areas) in the neural mechanisms processing basic temporal information like interval duration.