Frontal alpha asymmetry and negative mood: a cross-sectional study in older and younger adults

The data presented in this study are openly available in Open Science Framework and can be found here (accessed on 26 July 2022): https://osf.io/v7y62/.Frontal alpha asymmetry (FAA) has been associated with emotional processing and affective psychopathology. Negative and withdrawal stimuli and behaviors have been related to high levels of right cortical activity, while positive and approach stimuli and behaviors have been related to increased left cortical activity. Inconsistent results in terms of depressive and anxious symptoms and their relationship to FAA have been previously observed, especially at older ages. Additionally, no studies to date have evaluated whether loneliness, a negative feeling, is related to FAA. Therefore, this study aimed (i) to compare FAA between younger and older adults and (ii) to investigate the possible relationships between loneliness, depressive and anxious symptomatology with FAA in young and older adults. Resting electroencephalogram recordings of 39 older (Mage = 70.51, SD = 7.12) and 57 younger adults (Mage = 22.54, SD = 3.72) were analyzed. Results showed greater left than right cortical activity for both groups and higher FAA for older than younger adults. FAA was not predicted by loneliness, depressive or anxious symptomatology as shown by regression analyses. Findings bring clarity about FAA patterns at different ages and open the discussion about the relationship between negative emotional processing and frontal cortical imbalances, especially at older ages.This research was funded by Portuguese Foundation for Science and Technology (FCT) projects POCI-01-0145-FEDER-028682 (PTDC/PSI-GER/28682/2017) and NORTE-01-0145-FEDER-032152 (PTDC/PSI-GER/32152/2017) through national and European Regional Development (FEDER) funds. D.P. was supported by the FCT grant SFRH/BPD/120111/2016, and C.B. by FCT grant 2020.07157.BD. The Centre for Research in Psychology (CIPsi/UM-PSI/01662) is supported by FCT through the Portuguese State Budget (UIDB/01662/2020) and by the Portuguese Ministry of Education and Science through national and FEDER funds through COMPETE2020 under the PT2020 Partnership Agreement (POCI-01-0145-FEDER-007653)

Neural correlates of face familiarity in institutionalized children and links to attachment disordered behaviour

Background: One of the most well-documented sequelae of early maltreatment and institutionalisation is attachment problems, including behaviours under the labels of reactive attachment disorder (RAD) and disinhibited social engagement disorder (DSED). Despite growing evidence of the neurobiological effects of institutionalisation, the neural correlates of these behavioural patterns are largely unknown. Methods: The current study examined effects of both institutionalisation in general and attachment disordered behaviour, in particular, on brain-based markers of face processing, in 100 Portuguese children (70 currently institutionalised, 30 continuously raised by their families). Children’s neural processing of caregiver’s and stranger’s faces was assessed with Event-Related Potentials (ERPs). Results: Compared to children from the community, institutionalised children showed smaller amplitudes in the N170, to both stranger and caregiver faces. Amongst the institutionalised group, living in a setting with a higher children-to-caregivers’ ratio was associated with smaller P400 amplitudes. The display of DSED symptoms was associated with a smaller P1 to both faces, as well as a reduced differentiation between faces in P400 amplitudes and smaller P400 to the stranger’s face. In contrast, RAD symptoms were not associated with any ERP measures. Conclusions: Results replicate previously reported hypoactivation in institutionalised children, in a lessglobally deprived setting than past work, indicating that such a pattern is associated with lack of individualised care and increased symptoms of DSED.Acknowledgements The authors are grateful to Santiago Galdo-Alvarez for designing the ERP paradigm, to Alberto Crego for his assistance with EEG data pre-processing, and to Ines Fachada and Raquel Corval for their support with data collection. Special thanks go to the children, parents, and institutional staff who participated in the study. This work was supported by the Portuguese Foundation for Science and Technology [Grants PTDC/PSI-PCL/101506/008 and SFRH/BD/69840/2010]. The authors have declared that they have no competing or potential conflicts of interest.Key points Existing evidence of neural face processing in institutionalised children has previously been limited to settings of severe deprivation and the role of social/attachment behaviour scarcely investigated. We replicated findings of blunted amplitudes in a posterior component involved in face processing, in a less globally deprived setting than past work. Reduced ERP amplitudes and reduced neural differentiation between faces were associated with DSED, but not RAD, symptoms. Reduced ERP amplitudes were associated with exposure to a higher children-to-caregivers' ratio. These findings indicate that differences in neural processing of faces are associated with lack of individualised care, even in the absence of other types of deprivation, and with DSED. Interventions should address the deleterious interpersonal experience of being cared for by multiple caregivers but lacking one-to-one interactions, to which institutionalised children are exposed

What times should be used for fNIRS and EEG protocol?

fNIRS (Functional near-infrared spectroscopy) and EEG (Electroencephalogram) are two technologies that measure brain activity. Recently expanded to new fields, such as Design. These technologies are beginning to be applied simultaneously in the laboratory or in real life, as they allow researchers to collect distinct data - electrical activity in the form of brain waves and the concentration of oxygenated and deoxygenated hemoglobin (HbO and HbR), respectively. The purpose of this study is to present a review on the event timing applied individually to optimize the usage of both tools, and a reflection on how a study protocol should be designed for the integration of both technologies into a hybrid fNRIS-EEG recording. The results show that the purpose of the study and the type of stimulus or task to be done by the participants, must be considered since they determinate the events timing in each step of the protocol. Event timing includes longer durations when there is interaction between the participant and the stimulus, or for completion of a task. Additionally, the resting period for fNIRS signals baseline correction must be carefully considered for the convergence on the use of both technologies in the same protocol.FCT– Fundação para aCiência e Tecnologia with in the R&D Units Project Scope: UIDB/00319/2020. The authors would also like to thank the European Structural and Investment Funds in the FEDER component, through the Operational Competitiveness and Internationalization Programme (COMPETE 2020) [Project nº 039334; Funding Reference: POCI-01-0247-FEDER-039334] for the Grants of Iara Margolis and Rute Silva