Romantic love affects emotional processing of love-unrelated stimuli: An EEG/ERP study using a love induction task.

The aim of the present study was to investigate (a) the neural correlates of a love induction task (LIT) including listening to love-related songs and thinking about the romantic relationship, and (b) the effects of romantic love on the emotional processing of love-unrelated stimuli during a passive viewing task. The EEG was recorded in two groups of university students: people in love (Love Group, LG, N = 22, 19 F) and people not in love (Control Group, CG, N = 20, 15 F). The LIT induced higher pleasantness and arousal in the LG than in the CG, as well as higher alpha activity in occipital-right electrodes, suggesting active mental imagery and internal focused attention. During the picture viewing task, the LG displayed larger N1 amplitudes than the CG in response to unpleasant pictures, and lower amplitudes of the late positive potential to both pleasant and unpleasant pictures at frontal sites. Overall, these results suggest an early attentional modulation of the neural responses to unpleasant, mood-incongruent cues, followed by an implicit emotional down-regulation of arousing stimuli, which might have important implications for everyday attitudes and behaviors.

Electroencephalographic functional connectivity in extreme prematurity: a pilot study based on graph theory.

BACKGROUND: Connectivity studies based on functional magnetic resonance imaging (MRI) provided new insights in neonatal brain development but cannot be performed at bedside in the clinical setting. The electroencephalogram (EEG) connectivity has been less studied, particularly using the new approach based on graph theory. This study aimed to explore the functional EEG connectivity using graph theory analysis at an early post-conception age in extremely premature and late-preterm babies free of medical complications and overt brain damage. METHODS: Sixteen neonates (8 extremely low gestational age (ELGA) and 8 late-preterm infants), both groups having performed multichannel EEG recordings at 35 weeks' post-conception, were recruited in a single tertiary-level neonatal intensive care unit and well-baby nursery, respectively. Global (i.e., small-worldness) and local (i.e., clustering and strength) connectivity measures were calculated on a single-subject connectivity matrix of EEG data. RESULTS: Both ELGA and late-preterm infants showed small-worldness organization at 35 weeks' post-conception. The ELGA group had the strength parameter of the theta frequency band lower in the right than in the left hemisphere. This asymmetry did not emerge in the late-preterm group. Moreover, the mean strength parameter was significantly greater in the right hemisphere in the late preterms than in the ELGA group. CONCLUSION: EEG connectivity measures could represent an index of left-to-right maturation and developmental disadvantage in extremely preterm infants.

Time perception in childhood absence epilepsy: Findings from a pilot study.

OBJECTIVES: With this explorative study, we aimed to examine time perception in children with childhood absence epilepsy (CAE) and to compare those children with a matched control group. The study also investigated the association between the neuropsychological performance of the group with CAE and time judgment. We hypothesize that children with CAE could fail in time perception and that this may be because of a common underlying substrate with executive impairments. METHODS: Thirteen children with CAE, aged 6-13 years, and 17 healthy children were recruited. All children performed the time bisection task; the children with CAE also performed a cognitive and neuropsychological assessment. We performed a univariate analysis using each parameter of the bisection task (bisection point [BP]) and Weber ratio (WR) as dependent variables, the group (patients vs. controls) as fixed factors and age at evaluation and vocabulary scores as covariates. In the subgroup of patients, we correlated bisection task parameters with neuropsychological tests using a nonparametric partial correlation; the analysis has corrected for age at evaluation. RESULTS: The BP and WR measures differed between controls and patients with CAE. In the subgroup of patients also performing a neuropsychological assessment, we found a correlation between the WR measure and performance on the inhibition test (r = -0.641, p = .025), coding test (r = -0.815, p = .014), and Trail Making Test B (TMT B) (r = 0.72, p = .042). CONCLUSIONS: We found an altered time perception in a pilot study of a small group of children with CAE. A neurophysiological mechanism underlying CAE seems to influence cognitive and behavioral deficits and time sensibility.

The effects of focal and nonfocal cues on the neural correlates of prospective memory: insights from ERPs.

The present study is the first designed to investigate behavioral and event-related potential (ERP) correlates of the processes involved in focal and nonfocal prospective memory (PM) tasks. Focal tasks are those in which the features of the PM cue are easily extracted from the ongoing activity, whereas the process is more indirect in nonfocal tasks. Strategic monitoring was associated with a slowing of reaction times in ongoing trials and with frontal and parietal ERP modulations. These effects were greater in the nonfocal task, whereas they were smaller, or even absent for some individuals, in the focal task. This indicates that strategic monitoring is engaged to a greater extent in nonfocal tasks, whereas it is less extensively recruited, or not recruited at all by some individuals, in focal tasks. Indeed, the recognition of the PM cue might also occur automatically in focal tasks, as suggested by the FN400 increase in focal PM trials. Nonfocal tasks are supported by more controlled resources not only in retrieval, but also in postretrieval monitoring and coordinating processes. This was reflected in the enhancement of the prospective positivity and frontal slow wave observed in nonfocal PM trials. We interpreted these results as supporting the multiprocess view of PM.

Test-retest consistency of Virtual Week: A task to investigate prospective memory.

The present study reports test-retest consistency of Virtual Week, a well-known measure of prospective memory (PM) performance. PM is the memory associated with carrying out actions at a specific moment in the future. Patients with neurological disorders as well as healthy older adults often report PM dysfunctions that affect their everyday living. In Experiment 1, 19 younger and 20 older adults undertook the standard version of Virtual Week (version A). Older adults showed lower performance compared to younger participants. However, the discrepancy between groups was eliminated at retest. Experiment 2 was conducted to investigate if remembering of PM content determined the improvement observed in older adults at retest in Experiment 1. To this end we created a parallel version (version B) in which we varied the content of the PM actions. Fifty older adults were assigned to one of the two experimental conditions: Version A at test and version B at retest or vice versa (25 participants in each condition). Results showed no group differences in PM performance between version A and version B; moreover, no effect of test-retest was found. The study confirmed that Virtual Week is a reliable measure of PM performance and also provided a new parallel version that can be useful in clinical setting.

Low-frequency rTMS inhibitory effects in the primary motor cortex: Insights from TMS-evoked potentials.

The neuromodulatory effects of repetitive transcranial magnetic stimulation (rTMS) have been mostly investigated by peripheral motor-evoked potentials (MEPs). New TMS-compatible EEG systems allow a direct investigation of the stimulation effects through the analysis of TMS-evoked potentials (TEPs). We investigated the effects of 1-Hz rTMS over the primary motor cortex (M1) of 15 healthy volunteers on TEP evoked by single pulse TMS over the same area. A second experiment in which rTMS was delivered over the primary visual cortex (V1) of 15 healthy volunteers was conducted to examine the spatial specificity of the effects. Single-pulse TMS evoked four main components: P30, N45, P60 and N100. M1-rTMS resulted in a significant decrease of MEP amplitude and in a significant increase of P60 and N100 amplitude. There was no effect after V1-rTMS. 1-Hz rTMS appears to increase the amount of inhibition following a TMS pulse, as demonstrated by the higher N100 and P60, which are thought to originate from GABAb-mediated inhibitory post-synaptic potentials. Our results confirm the reliability of the TMS-evoked N100 as a marker of cortical inhibition and provide insight into the neuromodulatory effects of 1-Hz rTMS. The present finding could be of relevance for therapeutic and diagnostic purposes.

Physical active lifestyle promotes static and dynamic balance performance in young and older adults.

Although regular physical activity exposure leads to positive postural balance control (PBC) adaptations, few studies investigated its effects, or the one of inactivity, on PBC in populations of different age groups. Thus, this study investigated the impact of a physically active lifestyle on static and dynamic PBC in young and older adults. Thirty-five young physically active subjects (YA), 20 young sedentary subjects (YS), 16 physically active older adults (OA), and 15 sedentary older adults (OS) underwent a static and a dynamic PBC assessment. A force platform and an instrumented proprioceptive board were employed to measure the center of pressure (COP) trajectory and the anteroposterior oscillations, respectively. In static conditions, no significant differences were detected among groups considering the overall postural balance performance represented by the area of confidence ellipse values. Conversely, the YA highlighted a higher efficiency (i.e., lower sway path mean velocity) in PBC maintenance compared to the other groups (YA vs OA: p = 0.0057, Cohen's d = 0.94; YA vs OS p = 0.043, d = 1.07; YA vs YS p = 0.08, d = 0.67). OS exhibited an overall worse performance in dynamic conditions than YA and YS. Surprisingly, no differences were found between YS and OA for all the static and dynamic parameters considered. In conclusion, our results suggest that a physically active lifestyle may promote static and dynamic balance performance in young and older adults, thus with potentially positive effects on the age-related decline of postural balance performance. Dynamic PBC assessment seems more sensitive in detecting differences between groups than the static evaluation.

Detecting neurodevelopmental trajectories in congenital heart diseases with a machine-learning approach.

We aimed to delineate the neuropsychological and psychopathological profiles of children with congenital heart disease (CHD) and look for associations with clinical parameters. We conducted a prospective observational study in children with CHD who underwent cardiac surgery within five years of age. At least 18 months after cardiac surgery, we performed an extensive neuropsychological (intelligence, language, attention, executive function, memory, social skills) and psychopathological assessment, implementing a machine-learning approach for clustering and influencing variable classification. We examined 74 children (37 with CHD and 37 age-matched controls). Group comparisons have shown differences in many domains: intelligence, language, executive skills, and memory. From CHD questionnaires, we identified two clinical subtypes of psychopathological profiles: a small subgroup with high symptoms of psychopathology and a wider subgroup of patients with ADHD-like profiles. No associations with the considered clinical parameters were found. CHD patients are prone to high interindividual variability in neuropsychological and psychological outcomes, depending on many factors that are difficult to control and study. Unfortunately, these dysfunctions are under-recognized by clinicians. Given that brain maturation continues through childhood, providing a significant window for recovery, there is a need for a lifespan approach to optimize the outcome trajectory for patients with CHD.

Functional hemispheric asymmetries in humans: electrophysiological evidence from preterm infants.

In recent years, magnetic resonance imaging has allowed researchers to individuate the earlier morphological development of the right hemisphere compared with the left hemisphere during late-gestational development. Anatomical asymmetry, however, does not necessarily mean functional asymmetry, and whether the anatomical differences between hemispheres at this early age are paralleled by functional specialisations remains unknown. In this study, the presence of lateralised electrical brain activity related to both pitch detection and discrimination was investigated in 34 prematurely-born infants [24-34 gestational weeks (GWs)] all tested at the same post-conceptional age of 35 weeks. By means of a frequency-change oddball experimental paradigm, with 'standard' tones at 1000 Hz (P = 90%) and 'deviant' tones at 2000 Hz (P = 10%), we were able to record higher right event-related potential activity in the interval windows between 350 and 650 ms after stimulus onset. An explorative hierarchical cluster analysis confirmed the different distribution of the hemispheric asymmetry score in newborns < 30 weeks old. Here, we show electrophysiological evidence of the early functional right lateralisation for pitch processing (detection and discrimination) arising by 30 GWs, but not before, in preterm newborns despite the longer environmental sensorial experience of newborns < 30 GWs. Generally, these findings suggest that the earlier right structural maturation in foetal epochs seems to be paralleled by a right functional development.

Sociocognitive factors associated with nonadherence to medication after hospital discharge.

Poor adherence to prescribed medication is a well-known problem and continues to be a major challenge in all medical specialties. Unlike previous studies that have mainly focused on nonadherence behaviors in specific diseases, this study sought to examine socio-cognitive factors associated with nonadherence behavior in a sample of a general clinical population. A questionnaire investigating socio-demographic and cognitive factors and a telephone follow-up interview were administered to 84 patients recruited in a General Medicine Unit before their discharge. Half of the participants were informed about that follow-up procedure. One month after hospital discharge, 42% of uninformed patients reported nonadherence behaviors, as against 21% of informed patients. Middle-aged patients and short-term treatments were associated significantly more often with nonadherence. Among cognitive factors, patients' perceived risks and benefits of nonadherence, personal susceptibility to diseases, subjective health value, and reported memory failures were significantly associated with adherence. We conclude that a patient's perception may be more important than medication load, illness severity, and complexity of regimen in influencing medication adherence, and that a telephone call follow-up helps in monitoring medication adherence after hospital discharge.

The role of dual-task and task-switch in prospective memory: behavioural data and neural correlates.

Event-based prospective memory (PM) requires remembering the delayed execution of an intended action in response to a pre-specified PM cue while being actively engaged in an ongoing task in which the cue is embedded. To date, experimental paradigms vary as to whether or not they require participants immediately to stop working on the ongoing task whenever they encounter a PM event (cue) and directly switch to the prospective action (task-switch approach). Alternatively, several other paradigms used in the literature encourage participants to continue working on the ongoing task item after the cue, and only then, perform the prospective action (dual-task approach). The present study explores the possible behavioural and electrophysiological effects that both approaches may have on PM performance. Seventeen young adults performed both versions of a standard PM task in a counterbalanced order during which behavioural data and electroencephalogram (EEG) were recorded. Behavioural data showed a decrement in PM performance in the task-switch compared to the dual-task condition. In addition, EEG data revealed differences between the dual-task and task-switch approach in event-related potential (ERP) components associated with response inhibition and with post-retrieval monitoring (i.e. late positive complex). No differences between the two tasks were found with regard to the PM event detection processes (i.e. N300) and the retrieval of the intended action from long-term memory. In sum, findings demonstrate that it does make a difference which task approach is applied and suggest that dual-task and task-switch paradigms may result in different processing and neurophysiological dynamics particularly concerning attentional resources and cognitive control.

Face-name repetition priming in semantic dementia: a case report.

Repetition priming (RP) has been employed as a measure of implicit processing in patients suffering from a breakdown of semantic memory, as in the case of semantic dementia (SD), a subtype of frontotemporal lobar degeneration (FTLD). Here, we investigated face-name representation in a case of SD using a paradigm of within- and cross-domain repetition priming. Compared to ten healthy participants, SD patient did not show any facilitation when a famous name was primed by its own face (cross-domain) or when the prime was the same proper name (within-domain). Results are discussed within the hypothesis of a degradation of face and name representation, one of the most consistent accounts explaining semantic deficits in SD.

Deficits in prospective memory following damage to the medial subdivision of the mediodorsal thalamic nucleus.

Identifying the neurocognitive mechanisms that lead individuals remembering to execute an intention at the right moment (prospective memory, PM) and how such mechanisms are influenced by the features of that intention is a fundamental theoretical challenge. In particular, the functional contribution of subcortical regions to PM is still unknown. This study was aimed at investigating the role of the medial subdivision of the mediodorsal thalamic nucleus (mMDT) in PM, with particular focus on the processes that are mediated by the projections from/to this structure. We analysed the performance of a patient (OG) with a right-sided lesion involving the mMDT in a series of PM tasks that varied for focality (i.e., overlapping of processes for the PM and ongoing tasks) and emotional valence of the stimuli, comparing the patient's performance with that of a control group. We found that the mMDT damage led to deficits in PM that were modulated by focality and emotional valence. OG indeed showed: a greater cost in the ongoing performance when a non-focal PM task was added; a slowing down in retrieving the intentions, in particular when these were associated with focal PM cues; an abnormal performance in the task with positive PM cues. Our findings provide evidence of a contribution of mMDT to PM and suggest a modulation of prefrontal-dependent strategic monitoring and a possible interaction with the limbic structures in the integration of emotion and PM processes. They also give support to the still controversial idea that connections with the perirhinal cortex mediate familiarity-based recognition.

The Influence of Emotional Material on Encoding and Retrieving Intentions: An ERP Study in Younger and Older Adults.

Prospective memory is a cognitive process that comprises the encoding and maintenance of an intention until the appropriate moment of its retrieval. It is of highly relevance for an independent everyday life, especially in older adults; however, there is ample evidence that prospective memory declines with increasing age. Because most studies have used neutral stimuli, it is still an open question how emotional factors influence age-related differences in prospective remembering. The aim of the study was to investigate the influence of emotional material on prospective memory encoding, monitoring, maintaining, and retrieval in younger and older adults using behavioral and electrophysiological measures. We tested 24 younger adults (M = 26.4 years) and 20 older adults (M = 68.1 years) using a picture one-back task as ongoing activity with an embedded prospective memory instruction. The experimental task consisted of three sessions. In each session, participants had to encode series of images that represented the prospective memory cues for the consecutive block. The images were either of pleasant, unpleasant, or neutral valence. The pictures used in the ongoing task were likewise of pleasant, unpleasant, or neutral valence. Event-related potentials (ERPs) were recorded to assess the neural correlates of intention encoding, maintenance, and self-initiated retrieval. We did not find age differences between younger and older adults on the behavioral level. However, the ERP results revealed an interesting pattern that suggested for both age groups elevated attentional processing of emotional cues during encoding indicated by an elevated LPP for the emotional cues. Additionally, younger adults showed increased activity for unpleasant cues. During the maintenance phase, both age groups engaged in strategic monitoring especially for pleasant cues, which led to enhanced sustained positivity. During retrieval, older adults showed increased activity of ERP components related to cue detection and retrieval mainly for pleasant cues indicating enhanced relevance for those cues. In conclusion, emotional material may influence prospective remembering in older adults differently than in younger adults by supporting a mixture of top-down and bottom-up controlled processing. The results demonstrated a negativity bias in younger adults and a positivity bias in older adults.

Spectral analysis highlight developmental EEG changes in preterm infants without overt brain damage.

Early markers of neurological outcome in the absence of overt brain damage are scarce in extreme prematurity. The aim of this study was to compare spectral EEG values of infants born near term with those of infants born at extremely low gestational age (ELGA) but having attained near term age. We aimed also to evaluate whether spectral EEG features were related with neurological outcome. The ELGA group consisted of 12 neonates born between 23+2 and 27+6 weeks; the control group consisted of nine infants born 34-35+2 weeks, tested within the first week of life. All neonates underwent multichannel EEG recordings at 35 weeks post-conception. None of the subjects had apparent neurological abnormalities or risk factors at the time of recording. EEG data were transformed into the frequency domain and divided into delta (0.5-4Hz), theta (5-7Hz), alpha (8-13Hz), beta (14-20Hz) frequency bands; relative EEG power values were calculated. ELGA group was compared with the control group using a mixed analysis of variance. Outcome was evaluated at one year of age by Griffiths' scales. A principal effect of frequency and an interaction effect of frequency * group was found. The total relative power of the delta band was significantly higher in ELGA than in control group, whereas in the remaining frequency bands total relative power was lower in ELGA than in control group. Higher values of delta and lower values of alpha and beta spectral power correlated with poor outcome. We provide preliminary results suggesting that, as early as 35 weeks post conception, infants born extremely preterm fail to develop the age specific pattern of EEG spectral activity, in the absence of neurological neonatal risk.

TMS-evoked long-lasting artefacts: A new adaptive algorithm for EEG signal correction.

OBJECTIVE: During EEG the discharge of TMS generates a long-lasting decay artefact (DA) that makes the analysis of TMS-evoked potentials (TEPs) difficult. Our aim was twofold: (1) to describe how the DA affects the recorded EEG and (2) to develop a new adaptive detrend algorithm (ADA) able to correct the DA. METHODS: We performed two experiments testing 50 healthy volunteers. In experiment 1, we tested the efficacy of ADA by comparing it with two commonly-used independent component analysis (ICA) algorithms. In experiment 2, we further investigated the efficiency of ADA and the impact of the DA evoked from TMS over frontal, motor and parietal areas. RESULTS: Our results demonstrated that (1) the DA affected the EEG signal in the spatiotemporal domain; (2) ADA was able to completely remove the DA without affecting the TEP waveforms; (3). ICA corrections produced significant changes in peak-to-peak TEP amplitude. CONCLUSIONS: ADA is a reliable solution for the DA correction, especially considering that (1) it does not affect physiological responses; (2) it is completely data-driven and (3) its effectiveness does not depend on the characteristics of the artefact and on the number of recording electrodes. SIGNIFICANCE: We proposed a new reliable algorithm of correction for long-lasting TMS-EEG artifacts.

Handedness effects on interhemispheric transfer time: a TMS study.

The crossed-uncrossed difference (CUD) estimates the interhemispheric transfer time (ITT) through the corpus callosum. Previous research has shown that transcranial magnetic stimulation (TMS) to the occipital cortex determines an increased CUD during cognitive tasks. The aim of the present study was to investigate whether TMS stimulation applied at a motor stage can interfere with the ITT, comparing the performance of left- and right-handed people. Results showed a significant TMS effect, i.e. increasing reaction times were reported when stimulation was delivered on the left primary motor area. Effects were more evident when information was primarily perceived through the dominant hemisphere. Both left and right stimulations increased CUD times in right-handed subjects; however, left-handed subjects showed significant effects associated with left stimulation only. Furthermore, in both groups, TMS produced larger effects in the crossed than in the uncrossed condition. TMS stimulation increased reaction times, thus supporting the idea that the interhemispheric transfer of visuo-motor information occurs at a motor processing stage. The dominant hemisphere seems to play a major role within this process: our data indicates that left- and right-handed people have different ITT latencies associated with the transfer of information to the contralateral hemisphere.

The impact of a concurrent motor task on auditory and visual temporal discrimination tasks.

Previous studies have shown the presence of an interference effect on temporal perception when participants are required to simultaneously execute a nontemporal task. Such interference likely has an attentional source. In the present work, a temporal discrimination task was performed alone or together with a self-paced finger-tapping task used as concurrent, nontemporal task. Temporal durations were presented in either the visual or the auditory modality, and two standard durations (500 and 1,500 ms) were used. For each experimental condition, the participant's threshold was estimated and analyzed. The mean Weber fraction was higher in the visual than in the auditory modality, but only for the subsecond duration, and it was higher with the 500-ms than with the 1,500-ms standard duration. Interestingly, the Weber fraction was significantly higher in the dual-task condition, but only in the visual modality. The results suggest that the processing of time in the auditory modality is likely automatic, but not in the visual modality.

Differential effects of emotional cues on components of prospective memory: an ERP study.

So far, little is known about the neurocognitive mechanisms associated with emotion effects on prospective memory (PM) performance. Thus, this study aimed at disentangling possible mechanisms for the effects of emotional valence of PM cues on the distinct phases composing PM by investigating event-related potentials (ERPs). Participants were engaged in an ongoing N-back task while being required to perform a PM task. The emotional valence of both the ongoing pictures and the PM cues was manipulated (pleasant, neutral, unpleasant). ERPs were recorded during the PM phases, such as encoding, maintenance, and retrieval of the intention. A recognition task including PM cues and ongoing stimuli was also performed at the end of the sessions. ERP results suggest that emotional PM cues not only trigger an automatic, bottom-up, capture of attention, but also boost a greater allocation of top-down processes. These processes seem to be recruited to hold attention toward the emotional stimuli and to retrieve the intention from memory, likely because of the motivational significance of the emotional stimuli. Moreover, pleasant PM cues seemed to modulate especially the prospective component, as revealed by changes in the amplitude of the ERP correlates of strategic monitoring as a function of the relevance of the valence for the PM task. Unpleasant pictures seemed to modulate especially the retrospective component, as revealed by the largest old/new effect being elicited by unpleasant PM pictures in the recognition task.

Does predictability matter? Effects of cue predictability on neurocognitive mechanisms underlying prospective memory.

Prospective memory (PM) represents the ability to successfully realize intentions when the appropriate moment or cue occurs. In this study, we used event-related potentials (ERPs) to explore the impact of cue predictability on the cognitive and neural mechanisms supporting PM. Participants performed an ongoing task and, simultaneously, had to remember to execute a pre-specified action when they encountered the PM cues. The occurrence of the PM cues was predictable (being signaled by a warning cue) for some participants and was completely unpredictable for others. In the predictable cue condition, the behavioral and ERP correlates of strategic monitoring were observed mainly in the ongoing trials wherein the PM cue was expected. In the unpredictable cue condition they were instead shown throughout the whole PM block. This pattern of results suggests that, in the predictable cue condition, participants engaged monitoring only when subjected to a context wherein the PM cue was expected, and disengaged monitoring when the PM cue was not expected. Conversely, participants in the unpredictable cue condition distributed their resources for strategic monitoring in more continuous manner. The findings of this study support the most recent views-the "Dynamic Multiprocess Framework" and the "Attention to Delayed Intention" (AtoDI) model-confirming that strategic monitoring is a flexible mechanism that is recruited mainly when a PM cue is expected and that may interact with bottom-up spontaneous processes.