Arc and BDNF mediated effects of hippocampal astrocytic glutamate uptake blockade on spatial memory stages.

Glutamate is involved in fundamental functions, including neuronal plasticity and memory. Astrocytes are integral elements involved in synaptic function, and the GLT-1 transporter possesses a critical role in glutamate uptake. Here, we study the role of GLT-1, specifically located in astrocytes, in the consolidation, expression, reconsolidation and persistence of spatial object recognition memory in rats. Administration of dihydrokainic acid (DHK), a selective GLT-1 inhibitor, into the dorsal hippocampus around a weak training which only induces short-term memory, promotes long-term memory formation. This promotion is prevented by hippocampal administration of protein-synthesis translation inhibitor, blockade of Activity-regulated cytoskeleton-associated protein (Arc) translation or Brain-Derived Neurotrophic Factor (BDNF) action, which are plasticity related proteins necessary for memory consolidation. However, DHK around a strong training, which induces long-term memory, does not affect memory consolidation. Administration of DHK before the test session impairs the expression of long-term memory, and this effect is dependent of Arc translation. Furthermore, DHK impairs reconsolidation if applied before a reactivation session, and this effect is independent of Arc translation. These findings reveal specific consequences on spatial memory stages developed under hippocampal GLT-1 blockade, shedding light on the intricate molecular mechanisms, governed in part for the action of glia.

Unraveling the temporal interplay of slow-paced breathing and prefrontal transcranial direct current stimulation on cardiac indices of autonomic activity.

The neurovisceral integration model proposes that information flows bidirectionally between the brain and the heart via the vagus nerve, indexed by vagally mediated heart rate variability (vmHRV). Voluntary reduction in breathing rate (slow-paced breathing, SPB, 5.5 Breathing Per Minute (BPM)) can enhance vmHRV. Additionally, prefrontal transcranial direct current stimulation (tDCS) can modulate the excitability of the prefrontal region and influence the vagus nerve. However, research on the combination of SPB and prefrontal tDCS to increase vmHRV and other cardiac (heart rate (HR) and blood pressure) and peripheral (skin conductance) indices is scarce. We hypothesized that the combination of 20 min of SPB and prefrontal tDCS would have a greater effect than each intervention in isolation. Hence, 200 participants were divided into four groups: active tDCS with SPB, active tDCS with 15 BPM breathing, sham tDCS with SPB, and sham tDCS with 15 BPM breathing. Regardless of the tDCS condition, the 5.5 BPM group showed a significant increase in vmHRV over 20 minutes and significant decreases in HR at the first and second 5-min epochs of the intervention. Regardless of breathing condition, the active tDCS group exhibited higher HR at the fourth 5-min epoch of the intervention than the sham tDCS group. No other effects were observed. Overall, SPB is a robust technique for increasing vmHRV, whereas prefrontal tDCS may produce effects that counteract those of SPB. More research is necessary to test whether and how SPB and neuromodulation approaches can be combined to improve cardiac vagal tone.

Chemotherapy induces myeloid-driven spatial T-cell exhaustion in ovarian cancer.

To uncover the intricate, chemotherapy-induced spatiotemporal remodeling of the tumor microenvironment, we conducted integrative spatial and molecular characterization of 97 high-grade serous ovarian cancer (HGSC) samples collected before and after chemotherapy. Using single-cell and spatial analyses, we identify increasingly versatile immune cell states, which form spatiotemporally dynamic microcommunities at the tumor-stroma interface. We demonstrate that chemotherapy triggers spatial redistribution and exhaustion of CD8+ T cells due to prolonged antigen presentation by macrophages, both within interconnected myeloid networks termed "Myelonets" and at the tumor stroma interface. Single-cell and spatial transcriptomics identifies prominent TIGIT-NECTIN2 ligand-receptor interactions induced by chemotherapy. Using a functional patient-derived immuno-oncology platform, we show that CD8+T-cell activity can be boosted by combining immune checkpoint blockade with chemotherapy. Our discovery of chemotherapy-induced myeloid-driven spatial T-cell exhaustion paves the way for novel immunotherapeutic strategies to unleash CD8+ T-cell-mediated anti-tumor immunity in HGSC.

Stress priming transcranial direct current stimulation (tDCS) enhances updating of emotional content in working memory.

Transcranial direct current stimulation (tDCS) targeting the prefrontal cortex has emerged as a valuable tool in psychiatric research. Understanding the impact of affective states, such as stress at the time of stimulation, on the efficacy of prefrontal tDCS is crucial for advancing tDCS interventions. Stress-primed tDCS, wherein stress is used as a priming agent, has the potential to modulate neural plasticity and enhance cognitive functions, particularly in emotional working memory. However, prior research using stress-primed tDCS focused solely on non-emotional working memory performance, yielding mixed results. In this sham-controlled study, we addressed this gap by investigating the effects of stress-primed bifrontal tDCS (active versus sham) on both non-emotional and emotional working memory performance. The study was conducted in 146 healthy individuals who were randomly assigned to four experimental groups. The Trier Social Stress Test (TSST) or a control variant of the test was used to induce a stress versus control state. The results showed that stress priming significantly enhanced the effects of tDCS on the updating of emotional content in working memory, as evidenced by improved accuracy. Notably, no significant effects of stress priming were found for non-emotional working memory performance. These findings highlight the importance of an individual's prior affective state in shaping their response to tDCS, especially in the context of emotional working memory.

Trait-dependent effects of theta burst stimulation after psychosocial stress: a sham-controlled study in healthy individuals.

OBJECTIVE: Previous studies suggest that theta burst stimulation (TBS), a form of repetitive transcranial magnetic stimulation (rTMS), applied to the left dorsolateral prefrontal cortex (DLPFC) might be a promising approach to modulate stress-reactive rumination and the associated psychophysiological stress response. Crucially, individuals showing higher levels of trait rumination might benefit more from prefrontal stimulation. METHODS: In this sham-controlled study, 127 healthy individuals, with varying ruminative tendencies, received a single-session of intermittent TBS (iTBS), continuous TBS (cTBS) or sham TBS (sTBS) over the left DLPFC before being confronted with a Trier Social Stress Test. RESULTS: Results showed significant TBS effects on salivary cortisol as a function of trait rumination. cTBS, as compared to sTBS and iTBS, resulted in an attenuated stress-induced cortisol response in high compared to low trait ruminators. Although independent of trait rumination levels, cTBS showed positive effects on stress-related changes in mood and, both cTBS and iTBS (versus sham) presented an enhanced heart rate recovery following the stressor. We found no evidence for (trait rumination-dependent) TBS effects on stress-reactive rumination, negative affect, subjective stress or heart rate variability. CONCLUSIONS: cTBS shows beneficial effects on certain measures of stress, especially in high trait ruminators. SIGNIFICANCE: These findings highlight the importance of accounting for individual differences when examining TBS effects.

Dose-dependent response of prefrontal transcranial direct current stimulation on the heart rate variability: An electric field modeling study.

Transcranial direct current stimulation (tDCS) of the prefrontal cortex (PFC) modulates the autonomic nervous system by activating deeper brain areas via top-down pathway. However, effects on the nervous system are heterogeneous and may depend on the amount of current that penetrates. Therefore, we aimed to investigate the variable effects of tDCS on heart rate variability (HRV), a measure of the functional state of the autonomic nervous system. Using three prefrontal tDCS protocols (1.5, 3 mA and sham), we associated the simulated individual electric field (E-field) magnitude in brain regions of interest with the HRV effects. This was a randomized, double-blinded, sham-controlled and within-subject trial, in which healthy young-adult participants received tDCS sessions separated by 2 weeks. The brain regions of interest were the dorsolateral PFC (DLPFC), anterior cingulate cortex, insula and amygdala. Overall, 37 participants were investigated, corresponding to a total of 111 tDCS sessions. The findings suggested that HRV, measured by root mean squared of successive differences (RMSSD) and high-frequency HRV (HF-HRV), were significantly increased by the 3.0 mA tDCS when compared to sham and 1.5 mA. No difference was found between sham and 1.5 mA. E-field analysis showed that all brain regions of interest were associated with the HRV outcomes. However, this significance was associated with the protocol intensity, rather than inter-individual brain structural variability. To conclude, our results suggest a dose-dependent effect of tDCS for HRV. Therefore, further research is warranted to investigate the optimal current dose to modulate HRV.

Tracing back primed resistance in cancer via sister cells.

Exploring non-genetic evolution of cell states during cancer treatments has become attainable by recent advances in lineage-tracing methods. However, transcriptional changes that drive cells into resistant fates may be subtle, necessitating high resolution analysis. Here, we present ReSisTrace that uses shared transcriptomic features of sister cells to predict the states priming treatment resistance. Applying ReSisTrace in ovarian cancer cells perturbed with olaparib, carboplatin or natural killer (NK) cells reveals pre-resistant phenotypes defined by proteostatic and mRNA surveillance features, reflecting traits enriched in the upcoming subclonal selection. Furthermore, we show that DNA repair deficiency renders cells susceptible to both DNA damaging agents and NK killing in a context-dependent manner. Finally, we leverage the obtained pre-resistance profiles to predict and validate small molecules driving cells to sensitive states prior to treatment. In summary, ReSisTrace resolves pre-existing transcriptional features of treatment vulnerability, facilitating both molecular patient stratification and discovery of synergistic pre-sensitizing therapies.

ALDH1 immunoexpression in epithelial and stromal cells of oral lichen planus and lesions with lichenoid inflammatory infiltrate.

BACKGROUND: Oral Lichen Planus is a potential malignant disorder and shares clinical and histopathological features with other similar lesions. ALDH1 is a specific biomarker for stem cells identification, however its role in stromal cells of immune inflammatory infiltrate has not been explored. The aim of this study was to investigate the ALDH1 immunoexpression in epithelial and stromal cells of Oral Lichen Planus and other lesions with lichenoid inflammatory infiltrate. MATERIAL AND METHODS: 64 samples of Oral Lichen Planus, Oral Lichenoid Lesions, Oral Leukoplakia and Unspecific Chronic Inflammation were included. ALDH1 was evaluated in both epithelium and stromal cells. ALDH1+ cells ≥ 5% were considered positive in epithelium. Stromal cells were evaluated semi quantitatively. Fields were ranked in scores, according to criteria: 1 (0 to 10%); 2 (11 to 50%) and 3 (>50%). The mean value of the sum of the fields was the final score. Statistical differences among groups were investigated, considering p < 0.05. RESULTS: ALDH1 expression in epithelium was low in all groups without difference among them. ALDH1+ cells in the lamina propria were higher for Lichen Planus [2.0], followed by Leukoplakia [1.3], Lichenoid lesions [1.2] and control [1.1] (p<0.05). CONCLUSIONS: ALDH1 immunoexpression in epithelium of lichenoid potential malignant disorders did not show a contributory tool, however ALDH1 in stromal cells of lichen planus might be involved in the complex process of immune regulation associated with the pathogenesis of this disease.

Acute stress impacts reaction times in older but not in young adults in a flanker task.

Acute psychosocial stress effects on inhibition have been investigated in young adults, but little is known about these effects in older adults. The present study investigated effects of the Trier Social Stress Test on cognitive inhibition (i.e., ability to ignore distracting information) using a cross-over (stress vs. control) design in healthy young (N = 50; 18-30 years; Mage = 23.06) versus older adults (N = 50; 65-84 years; Mage = 71.12). Cognitive inhibition was measured by a letter flanker task and psychophysiological measures (cortisol, heart rate, subjective stress) validated the stress induction. The results showed that while stress impaired overall accuracy across age groups and sessions, stress (vs. control) made older adults' faster in session 1 and slower in session 2. Given that session 2 effects were likely confounded by practice effects, these results suggest that acute psychosocial stress improved older adults' RTs on a novel flanker task but impaired RTs on a practiced flanker task. That is, the interaction between stress and learning effects might negatively affect response execution when testing older adults on flanker tasks. If confirmed by future research, these results might have important implications especially in settings where repeated cognitive testing is performed under acute stress.

Adult age differences in the psychophysiological response to acute stress.

Age-related differences in the psychophysiology of the acute stress response are poorly understood given the limited number of studies and the high heterogeneity of findings. The present study contributes by investigating age differences in both the psychological and physiological responses to acute stress in a sample of healthy younger (N = 50; 18-30; Mage = 23.06; SD = 2.90) and older adults (N = 50; 65-84; Mage = 71.12; SD = 5.02). Specifically, the effects of psychosocial stress (i.e., age-adapted Trier Social Stress Test) were investigated at numerous timepoints throughout the stress response phases (i.e., baseline, anticipation, reactivity, recovery) on cortisol, heart rate, subjective stress, and anticipatory appraisal of the stressful situation. The study was conducted in a between-subject (younger vs. older) cross-over (stress vs. control) design. Results revealed age-related differences in both physiological and psychological variables: older adults had overall lower salivary cortisol levels in the stress and control conditions and lower stress-induced cortisol increase (i.e., AUCi). In addition, older adults' cortisol reactivity was delayed compared to younger adults. Older adults showed a lower heart rate response in the stress condition while no age differences were observed in the control condition. Finally, older adults reported less subjective stress and a less negative stress appraisal during the anticipation phase than younger adults, which could potentially explain lower physiological reactivity in this age group. Results are discussed in relation to the existing literature, potential underlying mechanisms, and future directions for the field.

The effects of left dorsolateral prefrontal transcranial direct current stimulation on episodic future thinking following acute psychosocial stress.

INTRODUCTION: Research on stress-related disorders and brain imaging suggests that (acute) stress might impact the capacity to mentally simulate specific episodic future events (EFT) through the effects of cortisol on brain regions supporting this cognitive function, such as the prefrontal cortices. This study aims to examine the mechanisms underlying this link, using transcranial Direct Current Stimulation (tDCS) over the left dorsolateral prefrontal cortex. METHODS: 60 healthy participants were subjected to the Montreal Imaging Stress Task (MIST), followed by either active or sham tDCS. After stimulation, the EFT task was administered. Salivary cortisol was measured throughout the protocol. RESULTS: Higher cortisol AUCi values were linked to less specific episodic future thoughts. Moreover, active tDCS enhanced EFT specificity irrespective of cortisol, especially in high trait ruminators. We did not observe an effect from active tDCS on cortisol AUCi, and equally there was no interaction effect between cortisol AUCi and stimulation condition predictive for EFT specificity. CONCLUSION: Although we did not find evidence for the effects of tDCS on the HPA-system, our data reveal a crucial link between two critical predictors of mental health for the first time, and provide a solution to help rehabilitate EFT deficits.Trial registration: Netherlands National Trial Register identifier: ntr004..

Accuracy of dental calcification stages for the identification of craniofacial pubertal growth spurt: proposal of referral parameters.

PURPOSE: This study primarily aimed to assess the accuracy of radiographic dental calcification parameters for the identification of specific craniofacial growth stages. METHODS: Permanent mandibular canines, premolars, and second molars of 288 patients, from 6 to 15 years old, were analysed on randomly selected panoramic radiographs, and categorised according to two calcification methods. Reproducibility analyses and data derived from panoramic records were correlated with the gold-standard method, as evaluated from lateral cephalometric teleradiographs. Accuracy tests were finally calculated, considering several cutoff points. RESULTS: Dental calcification methods showed "strong" to "almost perfect" intra- and inter-examiner reproducibility. Significant, although weak correlations were observed for all parameters. Canine and first premolar calcification stage 8 and second premolar and second molar stage 7 showed higher sensitivity rates for identifying the pubertal growth spurt period, as well as the stage F for these teeth. Canine and first premolar stages 10 and H obtained higher specificity rates for identifying the absence of post-pubertal period. CONCLUSIONS: The dental calcification parameters showed adequate reproducibility, in addition to significant correlations with cervical vertebrae stages. Radiographic dental calcification parameters used for the mandibular first premolar obtained high accuracy rates and were recommended for identifying specific craniofacial growth periods.

Depression and Suicide Risk in Mild Cognitive Impairment: The Role of Alzheimer's Disease Biomarkers.

BACKGROUND: Patients with depression and mild cognitive impairment (MCI) are at greater risk of developing dementia. Depression involves a higher risk of suicidal ideation (SI) and suicide attempts (SA). Biomarkers of Alzheimer's Disease (AD) could help to clarify the role of depression and SI in AD. METHOD: Fifty-nine participants aged > 50 with criteria of MCI positive (MCI-AD) (n=22) and negative (MCI-Non AD) (n=24) AD and healthy controls (HC) (n=13) were evaluated. We used the Geriatric Depression Scale (GDS-30) and the GDS-SI factor to measure depression and indirect risk for suicide, respectively. Additionally, AD biomarkers such as amyloid-ß (Aß), hyperphosphorilated tau (P-tau), and total tau (T-tau) in cerebrospinal fluid (CSF) were analyzed. RESULTS: No significant differences between the groups were found in depression. However, in the MCI-AD group, lower P-tau and T-tau levels were related to higher GDS-SI scores, suggesting that MCI-AD patients with lower AD pathology are at a higher risk of suicide. CONCLUSIONS: The result highlights the importance of considering SI in the initial phases of AD, and the potential role of AD biomarkers in early detection of symptoms.

Mediación parental en el uso de tecnologías móviles en niños y niñas costarricenses: Una aproximación metodológica mixta / The meaning of concepts dealing with basic emotions in children and adults

Resumen Aunque las emociones básicas son consideradas universales, su significado varía según las culturas y los grupos sociales. En el marco de la construcción social de los significados, aquí se analizan y comparan las representaciones semánticas de seis emociones básicas (alegría, tristeza, enojo, miedo, sorpresa, asco) activadas por 78 niños (9 a 11 años) y 78 adultos (20 a 40 años). En base a una tarea de producción de atributos semánticos, se construyó la representación semántica asociada a cada emoción para cada rango etario. Luego, utilizando la metodología provista por el análisis de redes sociales (ARS), se analizó la calidad intrínseca y las diferencias en cantidad y tipos de atributos, estructura de las redes, densidad y nivel de entropía, y el uso de la definición por negación. Los resultados indicaron que los mapas semánticos de niños y mayores demuestran que los adultos producen mayor cantidad y diversidad de atributos que los niños, pero que ambas poblaciones comparten el núcleo del significado de los conceptos evaluados. Asimismo, muestra que la escolarización conduce a la generación de más atributos taxonómicos, que en los niños prevalecen los atributos introspectivos, que la densidad y la entropía revelan cómo los conceptos se vinculan entre sí diferencialmente en ambas poblaciones y finalmente que, frente a la dificultad para encontrar definidoras de pertenencia a una clase, los niños recurren a operaciones de contraste categorial. Entre las redes semánticas de adultos y de niños se encuentran continuidades y divergencias. En ambos grupos se encuentran separadas las emociones positivas de las negativas, lo cual es consistente con las teorías que sostienen la importancia de la valencia hedónica en la comprensión de las emociones.

Abstract Although basic emotions are considered universal, their representation, associations and meaning vary among cultures and social groups. Within the framework of the socio-constructivist theory, where the meanings develop in the social context, this paper analyzes and compares the semantic representations of six basic emotions (Joy, Sadness, Anger, Fear, Surprise and Disgust), evoked by 78 children between 9 and 11 years old and 78 adults between 20 and 40 years old. Participants had to list a series of properties/features for each concept in a Property Listing Task (PLT). With the lists produced by the participants, their frequencies and other statistical properties were calculated, and the matrix of distances between concepts was obtained from the vectors defined by each of them. Thus, using the six aforementioned emotions as stimuli, the semantic representation associated with each emotion was elaborated for each age range. Once these were obtained, an analysis was carried out to evaluate the intrinsic quality and the differences in: (1) quantity and types of features produced; (2) structure of each of the semantic networks obtained, both by means of quadratic assignment procedure (QAP) and hierarchical clustering algorithms; (3) network density (that describes the portion of the potential connections in a network that are actual connections) and entropy level (that describe the level of randomness and the amount of information encoded in a network); (4) comparative use of definition by negation; (5) qualitative analysis of the features associated with each emotional concept. To carry out the bulk of these activities and analysis, we used the tools and procedures provided by Social Network Analysis (SNA). As a result: (1) regarding the number of features, adults produced significantly more associations. A chi-square analysis found significant differences between groups in the type of features evoked, with a primacy of taxonomic for adults and introspective for children; (2) the quadratic assignment procedure found a significant level of association of .59 between the two age groups. The groupings performed at the lowest level of demand for linkage between cluster members distinguish positive emotions from negative ones; higher levels of demand begin to disaggregate the groupings: first fear and sadness are separated, then anger, then the dyad constituted by both versions of disgust. The emotion of greater commonality between children and adults is joy; (3) the density of the total network is higher in children than in adults, and the concepts of joy, disgust and sadness present a lower entropy in children than in adults; (4) Children produce considerably more definitions by the negative than adults; (5) the most similar emotion between both groups is joy and the most dissimilar is disgust. In children, disgust responds to gustatory stimuli, in adults it is used with social metaphorical value. The results obtained show the semantic representation of basic emotions in children and adults, finding both continuities (e. g. joy) and divergences (e. g. disgust) associated with the context and life experience. In both age groups, positive and negative emotions are found to be separated, which is consistent with theories on the importance of hedonic valence in the understanding of emotions. There are also differences in categorization, either more thematically or taxonomically oriented.

EEG markers and subjective memory complaints in young and older people.

Subjective memory complaints (SMCs) have been related to subtle cognitive deficits and neural changes. In this study, we investigated whether EEG rhythms, usually altered in mild cognitive impairment and Alzheimer's disease, are also affected in SMCs compared to people without SMCs. Seventy-one older adults (55-74 years old) and 75 young people (18-34 years old) underwent 3 min of EEG recording in a resting-state condition with their eyes open (EO) and eyes closed (EC) and a comprehensive neuropsychological evaluation. The EEG measures included were power spectral delta (0.5-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (13-30 Hz), and EEG reactivity to EO. Compared to controls, older people with SMCs showed increased theta power and a loss of alpha reactivity to EO. Additionally, in older participants with SMCs, the theta power spectral was related to deficits in verbal memory. In contrast, we failed to find differences in the young people with SMCs, compared to the control group, in the power spectral or the EEG reactivity to EO. Our findings suggest that neurophysiological markers of brain dysfunction may identify cognitive changes even before they are observed on objective neuropsychological tests, at least in older people.

Depression and Suicide Risk in Mild Cognitive Impairment: The Role of Alzheimer’s Disease Biomarkers / Depresión y Riesgo de Suicidio en el Deterioro Cognitivo Leve: el Rol de los Biomarcadores de la Enfermedad de Alzheimer

Background: Patients with depression and mild cognitive impairment (MCI) are at greater risk of developing dementia. Depression involves a higher risk of suicidal ideation (SI) and suicide attempts (SA). Biomarkers of Alzheimer’s Disease (AD) could help to clarify the role of depression and SI in AD. Method: Fifty-nine participants aged > 50 with criteria of MCI positive (MCI-AD) (n=22) and negative (MCI-Non AD) (n=24) AD and healthy controls (HC) (n=13) were evaluated. We used the Geriatric Depression Scale (GDS-30) and the GDS-SI factor to measure depression and indirect risk for suicide, respectively. Additionally, AD biomarkers such as amyloid-ß (Aß), hyperphosphorilated tau (P-tau), and total tau (T-tau) in cerebrospinal fluid (CSF) were analyzed. Results: No significant differences between the groups were found in depression. However, in the MCI-AD group, lower P-tau and T-tau levels were related to higher GDS-SI scores, suggesting that MCI-AD patients with lower AD pathology are at a higher risk of suicide. Conclusions: The result highlights the importance of considering SI in the initial phases of AD, and the potential role of AD biomarkers in early detection of symptoms.(AU)

Antecedentes: Los pacientes con depresión y deterioro cognitivo leve (DCL) tienen un alto riesgo de desarrollar demencia. La depresión implica un alto riesgo de ideación suicida (IS) e intentos de suicidio (AS). Los biomarcadores de la enfermedad de Alzheimer (EA) pueden clarificar el papel de la depresión e IS en la EA. Método: Cincuenta y nueve participantes >50 años con criterios de DCL-EA positivo (DCL-EA; 22) y negativo (DCL-NoEA; 24) y 13 controles sanos. La depresión fue evaluada con la Escala Geriátrica de Depresión (GDS-30) y la IS con el factor GDS-IS. Además, se midieron los siguientes biomarcadores en el líquido cefalorraquídeo: ß-amiloide (ß-A), tau hiperfosforilada (H-tau) y total (T-tau). Resultados: No se encontraron diferencias significativas entre los tres grupos de participantes en depresión o en IS. Sin embargo, en el grupo DCL-EA, niveles más bajos de H-tau y T-tau, indicadores de menor patología EA, se relacionaron significativamente con mayor riesgo de suicidio indirecto. Conclusiones: Este resultado subraya la importancia de considerar la IS en fases iniciales de EA, y el potencial papel de los biomarcadores de EA para detectar sus síntomas.(AU)

Double the dose, double the impact? Effects of iTBS on salivary cortisol in stressed healthy volunteers.

There is a growing interest in applying double-dose repetitive transcranial Magnetic Stimulation (rTMS) as a therapeutic tool for stress-related psychiatric disorders. Such stimulation protocols may shorten the treatment duration and may result in faster symptom improvement. Currently, theta-burst stimulation (TBS) protocols have gained attention because of their significantly reduced treatment duration, compared to conventional rTMS. However, the effect of one or twice daily rTMS sessions remains unclear in relation to stress. Using a two-period cross-over design, we examined the impact of double-dosed intermittent (TBS) over the left dorsolateral prefrontal cortex on stress responses (salivary cortisol) in thirty-eight healthy participants after being stressed by a validated psychosocial stress task: the Trier Social Stress Test. After the first active iTBS session, as contrasted to sham, no differential effects on salivary output were observed. However, after the second active session, there was a significantly smaller decrease of salivary cortisol concentrations in the active iTBS condition compared to sham. Our results suggest that double-dosed iTBS after being stressed might differently affect stress recovery compared to a single session of iTBS.

Pre-pandemic Psychobiological Features Predict Impact of COVID-19 Confinement on Loneliness.

The coronavirus disease 2019 (COVID-19) pandemic led to various government-imposed limitations on social interaction and strict home confinement. Such involuntary social-distancing policies can exacerbate feelings of loneliness and alter emotional well-being. Dysregulation of the hypothalamic-pituitary-adrenocortical (HPA) axis is a potential mechanism for loneliness' deleterious health effects. In this study, we explored whether pre-pandemic diurnal cortisol output (AUC G ), a measure of HPA axis function, may predict the propensity to changes in loneliness during long-term COVID-19 home confinement and if extraversion would moderate this relationship. This association has been explored by analysing the impact of COVID-19 pandemic and strict home confinement on social and emotional loneliness in 45 Spanish young adults. Diurnal cortisol levels were measured from five saliva samples obtained across a day just before the pandemic, and data about participants' perceived loneliness, empathic state, extraversion, and prospective volunteering were obtained both before and during the confinement. Participants' social and family loneliness increased during long-term strict home confinement, while prospective volunteering tendencies and extraversion decreased. Importantly, after adjusting for relevant confounders, moderation analyses revealed that in young adults with high pre-pandemic extraversion, a higher AUC G predicted a larger increase in social loneliness during confinement, while in individuals with low extraversion, AUC G was negatively related to change in loneliness. Our findings highlight the utility of pre-pandemic diurnal cortisol output in predicting the social impact of COVID-19 home confinement, presenting this hormone as a potential biomarker for a priori identification of at-risk groups during public health crises.

Optimism as a protective factor against the psychological impact of COVID-19 pandemic through its effects on perceived stress and infection stress anticipation.

The 2019 coronavirus disease (COVID-19) and the recommended social isolation presented a challenge to people's mental health status. Optimism is a psychological factor that plays a key role in the evaluation of stressful situations. The purpose of this study was to investigate the mediating role of perceived stress and Covid-19-related stress anticipation in the relationship between optimism and post-traumatic stress symptoms. Our sample included 1015 participants ranging in age from 18 to 79 years, 80% of whom were Spaniards. At the beginning of the worldwide pandemic, participants were confined to their homes for at least seven days and completed an online survey measuring various sociodemographic and psychological variables. We found an indirect effect of optimism on intrusion and hyperarousal through perceived stress and stress anticipation. In addition, we observed an indirect effect of optimism on avoidance through perceived stress. Finally, the results showed a significant indirect effect of optimism on the total post-traumatic stress symptoms score through perceived stress and stress anticipation. Our results indicate that positive beliefs inherent to optimism are related to less psychological impact of the COVID-19 outbreak.

Hormonal changes of intimate partner violence perpetrators in response to brief social contact with women.

This study investigated whether men with a history of real-life aggressive, dominant behavior show increases in testosterone and cortisol levels after brief social contact with women. Furthermore, we tested the prediction that such changes in hormones would be larger than those observed previously in young male students. Sixty-seven male participants convicted of intimate partner violence (IPV) either had brief social contact with a female confederate (experimental condition) or a male confederate (control condition). We also performed meta-analyses to investigate whether IPV perpetrators' hormonal responses were larger than the typical responses of young male students in prior studies. All statistical analyses were preregistered. Change in testosterone did not differ across experimental conditions, and testosterone in the IPV perpetrators actually declined from baseline in the female confederate condition. Our meta-analysis showed that this testosterone decrease was different from the testosterone increase typically observed in young male students. The cortisol levels of IPV perpetrators did not change in response to contact with women. This result was consistent with our meta-analysis since young male students also did not experience a cortisol change in response to interactions with women. In sum, our findings provide no evidence that male IPV perpetrators exhibit larger hormone increases to brief interactions with women, although it is possible that the men in this sample did not perceive the social contact period as a courtship opportunity. These results suggest that hormone reactivity to social encounters may differ across subject populations and depend on how subjects perceive social situations within laboratory settings.