The NED foundation experience: A model of global neurosurgery.

Introduction: The Neurosurgery Education and Development (NED) Foundation (NEDF) started the development of local neurosurgical practice in Zanzibar (Tanzania) in 2008. More than a decade later, multiple actions with humanitarian purposes have significantly improved neurosurgical practice and education for physicians and nurses. Research question: To what extent could comprehensive interventions (beyond treating patients) be effective in developing global neurosurgery from the outset in low and middle-income countries? Material and method: A retrospective review of a 14- year period (2008-2022) of NEDF activities highlighting landmarks, projects, and evolving collaborations in Zanzibar was carried out. We propose a particular model, the NEDF model, with interventions in the field of health cooperation that have simultaneously aimed to equip, treat, and educate in a stepwise manner. Results: 138 neurosurgical missions with 248 NED volunteers have been reported. In the NED Institute, between Nov 2014-Nov 2022, 29635 patients were seen in the outpatient clinics and 1985 surgical procedures were performed. During the course of NEDF's projects, we have identified three different levels of complexity (1, 2 and 3) that include the areas of equipment ("equip"), healthcare ("treat") and training ("educate"), facilitating an increase of autonomy throughout the process. Discussion and Conclusion: In the NEDF's model, the interventions required in each action area (ETE) are coherent for each level of development (1, 2 and 3). When applied simultaneously, they have a greater impact. We believe the model can be equally useful for the development of other medical and/or surgical specialties in other low-resource healthcare settings.

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.

Verbal fluency in school-aged Spanish children: analysis of clustering and switching organizational strategies, employing different semantic categories and letters / Fluidez verbal en niños españoles en edad escolar: análisis de las estrategias organizativas de agrupación y cambio, empleando diferentes categorías semánticas y letras

The verbal fluency task is a measure of cognitive flexibility and search strategy within the lexicon and semantic topic. The use of organizational strategies was tested in healthy Spanish children divided in two groups: group 1 of younger children and group 2 of older children introducing different letters and semantic categories. Semantic fluency was greater than phonological fluency in both age groups. In addition, older children showed better performance of both fluencies than younger children. From the phonological analyses, younger children evoked more word with the PMR letter group than with the FAS one. Moreover, an improvement of semantic fluency associated with the animal's category faced to meals and drink was observed only in the younger children group. In respect to organizational strategies, older children used more switches specifically in FAS group and more clusters for the meals or drinks category compared with the older children group. The relationships between the number of words evoked and the number of clusters and switches for both VF tasks were significant and positive. These data suggest that the type of letter and the semantic category employed in the VF evaluation modulate the verbal fluency performance in both groups of age.

La tarea de fluidez verbal es una medida de flexibilidad cognitiva y estrategia de búsqueda dentro del contenido léxico y semántico. Se evaluó el uso de estrategias organizativas en niños españoles sanos divididos en dos grupos: grupo 1 de niños más pequeños y grupo 2 de niños mayores introduciendo diferentes letras y categorías semánticas. La fluidez semántica fue mayor que la fluidez fonológica en ambos grupos de edad. Además, los niños mayores mostraron un mejor rendimiento de ambas fluencias que los niños más pequeños. A partir de los análisis fonológicos, los niños más pequeños evocaron más palabras con el grupo de letras PMR que con el de FAS. Además, se observó una mejora de la fluidez semántica asociada con la categoría animales frente a la categoría comidas y bebidas únicamente en el grupo de niños más pequeños. Con respecto a las estrategias organizativas, los niños mayores utilizaron más cambios, específicamente en el grupo FAS y más agrupamientos para la categoría de comidas o bebidas, en comparación con el grupo de niños mayores. Las relaciones entre el número de palabras evocadas y el número de agrupamientos y cambios para ambas tareas de VF fueron significativas y positivas. Estos datos sugieren que el tipo de letra y la categoría semántica empleada en la evaluación de la VF modulan el rendimiento en fluidez verbal en ambos grupos de edad.(AU)

Educational level as a protective factor against the influence of depressive symptoms on cognition in older adults: implications for functional independence during a 10-year follow-up.

OBJECTIVES: To examine whether the educational level moderates the relationship between baseline depressive symptoms and cognitive functioning at 5- and 10-year follow-ups in older adults, considering the association between cognitive functioning and difficulty with activities of daily living (ADL). DESIGN: Using a prospective design, a path analysis was performed. SETTING: In-home, face-to-face interviews and self-administered questionnaires, within the National Social Life, Health, and Aging Project. PARTICIPANTS: In total, 1,461 participants (mean age = 66.62) were followed up from Wave 1 (baseline) to Wave 2 (at 5 years) and Wave 3 (at 10 years). MEASUREMENTS: Depressive symptoms were assessed at baseline. Cognitive functioning and difficulty with ADL were assessed at baseline and at 5 and 10 years. RESULTS: Educational level moderates the relationship between depressive symptoms and cognitive functioning at 5 years (ß = 0.07, SE = 0.03, p = 0.04, Cohen's f2 = 0.02), being depressive symptoms related to poor cognitive functioning only at low educational levels. Cognitive functioning predicts difficulty with ADL at 5 and 10 years (ß = -0.08, SE = 0.03, p = 0.008, Cohen's f2 = 0.01; ß = -0.09, SE = 0.03, p = 0.006, Cohen's f2 = 0.02). The proposed model yielded excellent fit (CFI = 1.00, RMSEA = 0.0001, 90% CI 0.0001-0.03, SRMR = 0.004, and χ2(8) = 7.16, p = 0.52). CONCLUSIONS: Cognitive reserve may act as a protective factor against the effect of depressive symptoms on cognition in older adults, which, in turn, is relevant to their functional independence.

Magnocellular Bias in Exogenous Attention to Biologically Salient Stimuli as Revealed by Manipulating Their Luminosity and Color.

Exogenous attention is a set of mechanisms that allow us to detect and reorient toward salient events-such as appetitive or aversive-that appear out of the current focus of attention. The nature of these mechanisms, particularly the involvement of the parvocellular and magnocellular visual processing systems, was explored. Thirty-four participants performed a demanding digit categorization task while salient (spiders or S) and neutral (wheels or W) stimuli were presented as distractors under two figure-ground formats: heterochromatic/isoluminant (exclusively processed by the parvocellular system, Par trials) and isochromatic/heteroluminant (preferentially processed by the magnocellular system, Mag trials). This resulted in four conditions: SPar, SMag, WPar, and WMag. Behavioral (RTs and error rates in the task) and electrophysiological (ERPs) indices of exogenous attention were analyzed. Behavior showed greater attentional capture by SMag than by SPar distractors and enhanced modulation of SMag capture as fear of spiders reported by participants increased. ERPs reflected a sequence from magnocellular dominant (P1p, ≃120 msec) to both magnocellular and parvocellular processing (N2p and P2a, ≃200 msec). Importantly, amplitudes in one N2p subcomponent were greater to SMag than to SPar and WMag distractors, indicating greater magnocellular sensitivity to saliency. Taking together, results support a magnocellular bias in exogenous attention toward distractors of any nature during initial processing, a bias that remains in later stages when biologically salient distractors are present.

Exogenous attention to fear: Differential behavioral and neural responses to snakes and spiders.

Research has consistently shown that threat stimuli automatically attract attention in order to activate the defensive response systems. Recent findings have provided evidence that snakes tuned the visual system of evolving primates for their astute detection, particularly under challenging perceptual conditions. The goal of the present study was to measure behavioral and electrophysiological indices of exogenous attention to snakes, compared with spiders - matched for rated fear levels but for which sources of natural selection are less well grounded, and to innocuous animals (birds), which were presented as distracters, while participants were engaged in a letter discrimination task. Duration of stimuli, consisting in a letter string and a concurrent distracter, was either presented for 180 or 360ms to explore if the stimulus duration was a modulating effect of snakes in capturing attention. Results showed a specific early (P1) exogenous attention-related brain potential with maximal amplitude to snakes in both durations, which was followed by an enhanced late attention-related potential (LPP) showing enhanced amplitudes to spiders, particularly under the longer exposure durations. These results suggest that exogenous attention to different classes of threat stimuli follows a gradual process, with the most evolutionary-driven stimulus, i.e., snakes, being more efficient at attracting early exogenous attention, thus more dependent on bottom-up processes.

Autonomic markers associated with generalized social phobia symptoms: heart rate variability and salivary alpha-amylase.

The study of autonomic nervous system changes associated with generalized social phobia (GSP) disorder has increased in recent years, showing contradictory results. The present study aimed to evaluate how young people with GSP reacted before, during, and after exposure to the Trier Stress Social Test (TSST), focusing on their autonomic changes (heart rate variability (HRV) and salivary alpha-amylase (sAA)) compared to a control group (non-GSP). Some psychological variables were also considered. Sex was specifically studied as a possible modulator of autonomic fluctuations and psychological state. Eighty young people were randomly distributed into two counterbalanced situations: stress condition (N = 18 and 21 for GSP and non-GSP, respectively) and control condition (N = 21 and 20 for GSP and non-GSP, respectively), where cardiovascular variables were continuously recorded. Psychological questionnaires about mood and perceived stress were filled out, and five saliva samples were collected to analyze sAA. GSP participants showed higher values on low- and high-frequency ratios (HR domains), compared to non-GSP people, during exposure to the TSST, but no differences were observed after the stressor. Furthermore, the two groups did not differ in sAA. Importantly, positive affect in GSP participants was modulated by sex. The present study suggests that the balance between high- and low-frequency domains of HRV is a key cardiovascular marker reflecting the stress response of GSP people, as well the importance of sex in positive affect when facing a stressful situation.

Working memory of emotional stimuli: Electrophysiological characterization.

Memorizing emotional stimuli in a preferential way seems to be one of the adaptive strategies brought on by evolution for supporting survival. However, there is a lack of electrophysiological evidence on this bias in working memory. The present study analyzed the influence of emotion on the updating component of working memory. Behavioral and electrophysiological indices were measured from a 3-back task using negative, neutral, and positive faces. Electrophysiological data evidenced an emotional influence on the working memory sensitive P3 component, which presented larger amplitudes for negative matching faces compared to neutral ones. This effect originated in the superior parietal cortex, previously reported to be involved in N-back tasks. Additionally, P3 results showed a correlation with reaction times, where higher amplitudes were associated with faster responses for negative matching faces. These findings indicate that electrophysiological measures seem to be very suitable indices of the emotional influence on working memory.