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The vast oak-dominated forests of the Zagros Mountains in southwestern Iran currently undergo large-scale dieback driven by a combination of drought and increasing incidence of charcoal disease caused by the fungal pathogens Biscogniauxia mediterranea and Obolarina persica. Here, we explore the interactive effects between drought and charcoal disease agents on the physiology and biochemistry of Quercus infectoria and Quercus libani seedlings. The combination of pathogen attack and water limitation hampered plant development, especially in Q. libani seedlings, negatively affecting growth, biomass production, photosynthetic efficiency, and leaf water potential. An increase in markers of oxidative damage together with the upregulation of the antioxidant defense revealed that drought stress and pathogen infection led to pro-oxidative conditions in both oak species, especially in Q. libani, where larger changes in malondialdehyde and hydrogen peroxide occurred. The upregulation of the antioxidant system was more prominent in Q. infectoria than in Q. libani, resulting in enhanced enzyme activity and accumulation of non-enzymatic antioxidants. Fungal infection stimulated the activity of chitinase, phenylalanine ammonia lyase and β-1,3-glucanase in Q. infectoria leaves and this response became more pronounced under water shortage. Our study highlights that drought stress greatly intensifies the effects of the charcoal disease. Moreover, our findings imply superior stress resistance of Q. infectoria conferred by a highly efficient antioxidant system, strong osmotic adjustment (through proline), and increases in resistance enzymes and secondary metabolites (phenols and flavonoids). Future investigations should focus on adult trees in their natural habitat including interactions with soil factors and other pathogens like nematodes, bacteria and other fungi. Because the present research was conducted on oak seedlings, the findings can be considered by forest nursery managers.

Aging is associated with increased difficulty in facial emotion identification, possibly due to age-related network change. The neuropeptide oxytocin (OT) facilitates emotion identification, but this is understudied in aging. To determine the effects of OT on dynamic facial emotion identification across adulthood, 46 young and 48 older participants self-administered intranasal OT or a placebo in a randomized, double-blind procedure. Older participants were slower and less accurate in identifying emotions. Although there was no behavioral treatment effect, partial least squares analysis supported treatment effects on brain patterns during emotion identification that varied by age and emotion. For young participants, OT altered the processing of sadness and happiness, whereas for older participants, OT only affected the processing of sadness (15.3% covariance, p = 0.004). Furthermore, seed partial least squares analysis showed that older participants in the OT group recruited a large-scale amygdalar network that was positively correlated for anger, fear, and happiness, whereas older participants in the placebo group recruited a smaller, negatively correlated network (7% covariance, p = 0.002). Advancing the literature, these findings show that OT alters brain activity and amygdalar connectivity by age and emotion.

Introduction: Converging evidence suggests that both emotional and cognitive processes are critically involved in moral judgment, and may be mediated by discrete parts of the prefrontal cortex. The current study aimed at investigating the mediatory effect of right Frontopolar Cortex (rFPC) on the way that emotions affect moral judgments. Methods: Six adult patients affected by rFPC and 10 healthy controls were included in the study. Participants made judgements on moral dilemmas after being shown either neutral or emotional pictures. The role of rFPC in executive control and emotional experience was also examined. Results: The study results showed that inducing an emotional state increased the number of utilitarian responses both in the patients and controls. However, no significant differences were observed between the patients and controls in response time or the number of utilitarian responses. Also, no significant differences were observed in personal and impersonal dilemmas before and after the emotion induction in intergroup comparisons. Results of the executive control tasks showed reduced performance in patients affected by rFPC compared with the controls. Conclusion: The results of the current study suggested that rFPC might not have a direct role in mediating emotional processes during moral judgments, but possibly this region is important in a network supporting executive control functions.

The volumetric and morphometric examination of hippocampus formation subfields in a longitudinal manner using in vivo MRI could lead to more sensitive biomarkers for neuropsychiatric disorders and diseases including Alzheimer’s disease, as the anatomical subregions are functionally specialised. Longitudinal processing allows for increased sensitivity due to reduced confounds of inter-subject variability and higher effect-sensitivity than cross-sectional designs. We examined the performance of a new longitudinal pipeline (Longitudinal Automatic Segmentation of Hippocampus Subfields [LASHiS]) against three freely available, published approaches. LASHiS automatically segments hippocampus formation subfields by propagating labels from cross-sectionally labelled time point scans using joint-label fusion to a non-linearly realigned ‘single subject template’, where image segmentation occurs free of bias to any individual time point. Our pipeline measures tissue characteristics available in in vivo high-resolution MRI scans, at both clinical (3 Tesla) and ultra-high field strength (7 Tesla) and differs from previous longitudinal segmentation pipelines in that it leverages multi-contrast information in the segmentation process. LASHiS produces robust and reliable automatic multi-contrast segmentations of hippocampus formation subfields, as measured by higher volume similarity coefficients and Dice coefficients for test-retest reliability and robust longitudinal Bayesian Linear Mixed Effects results at 7 T, while showing sound results at 3 T. All code for this project including the automatic pipeline is available at https://github.com/CAIsr/LASHiS

In logical reasoning, difficulties in inhibition of currently-held beliefs may lead to unwarranted conclusions, known as belief bias. Aging is associated with difficulties in inhibitory control, which may lead to deficits in inhibition of currently-held beliefs. No study to date, however, has investigated the underlying neural substrates of age-related differences in logical reasoning and the impact of belief load. The aim of the present study was to delineate age differences in brain activity during a syllogistic logical reasoning task while the believability load of logical inferences was manipulated. Twenty-nine, healthy, younger and thirty, healthy, older adults (males and females) completed a functional magnetic resonance imaging experiment in which they were asked to determine the logical validity of conclusions. Unlike younger adults, older adults engaged a large-scale network including anterior cingulate cortex (ACC) and inferior frontal gyrus (IFG) during conclusion stage. Our functional connectivity results suggest that while older adults engaged the ACC network to overcome their intuitive responses for believable inferences, the IFG network contributed to higher control over responses during both believable and unbelievable conditions. Our functional results were further supported by structure-function-behavior analyses indicating the importance of cingulum bundle and uncinate fasciculus integrity in rejection of believable statements. These novel findings lend evidence for age-related differences in belief bias, with potentially important implications for decision making where currently-held beliefs and given assumptions are in conflict.

Previous findings indicate age-related differences in frontal-amygdala connectivity during emotional processing. However, direct evidence for age differences in brain functional activation and connectivity during emotional processing and concomitant behavioral implications is lacking. In the present study, we examined the impact of aging on the neural signature of selective attention to emotional information during working memory (WM) encoding. Participants completed an emotional WM task in which they were asked to attend to emotional targets and ignore irrelevant distractors. Despite an overall reduction in accuracy for older relative to younger adults, no behavioral age effect was observed as a function of emotional valence. The functional connectivity patterns of left ventrolateral prefrontal cortex showed that younger adults recruited one network for encoding of both positive and negative emotional targets and this network contributed to higher memory accuracy in this cohort. Older adults, on the other hand, engaged two distinct networks for encoding of positive and negative targets. The functional connectivity analysis using left amygdala further demonstrated that older adults recruited one single network during encoding of positive as well as negative targets whereas younger adults recruited this network only for encoding of negative items. The engagement of amygdala functional network also contributed to higher memory performance and faster response times in older adults. Our findings provide novel insights into the differential roles of functional brain networks connected to the medial PFC and amygdala during encoding of emotionally-valenced items with advancing age.

Normal adult aging is associated with difficulties in processing social cues to emotions such as anger and also altered motivation to focus more on positive than negative information. Gaze direction is an important modifier of the social signals conveyed by an emotion, for example, an angry face looking directly at you is considerably more threatening than an angry face looking away. In the present study we tested the hypothesis that older adults would show less neural differentiation to angry faces with direct and avert gaze compared to younger people, with the opposite prediction for happy faces. Healthy older (65-75 years; mean = 69.75) and younger (17-27 years; mean = 20.65) adults completed a functional magnetic resonance imaging experiment in which they were asked to identify happy and angry expressions displayed either with direct or averted gaze. While younger adults showed neural sensitivity to eye-gaze direction during recognition of angry expressions, older adults showed no effect of eye-gaze direction on neural response. In contrast, older adults showed sensitivity to eye-gaze direction during recognition of happy expressions but younger adults did not. Additionally, brain-behavior correlations were conducted to investigate the relationships between emotion recognition and mentalizing brain network in both age groups. Younger (but not older) adults' social cognitive performance was differentially correlated with activation in 2 brain networks when looking at angry faces with direct compared to averted gaze. These novel findings provide evidence for age-related differences in the neural substrates underlying the capacity to integrate facial affect and eye-gaze cues. The results of this study suggest that age-related differences in integrating facial cues may be related to engagement of the mentalizing network, with potentially important implications for social cognitive functioning in late adulthood.

In prospective memory (PM), an intention to act in response to an external event is formed, retained, and at a later stage, when the event occurs, the relevant action is performed. PM typically shows a decline in late adulthood, which might affect functions of daily living. The neural correlates of this decline are not well understood. Here, 15 young (6 female; age range=23-30years) and 16 older adults (5 female; age range=64-74years) were scanned with fMRI to examine age-related differences in brain activation associated with event-based PM using a task that facilitated the separation of transient and sustained components of PM. We show that older adults had reduced performance in conditions with high demands on prospective and working memory, while no age-difference was observed in low-demanding tasks. Across age groups, PM task performance activated separate sets of brain regions for transient and sustained responses. Age-differences in transient activation were found in fronto-striatal and MTL regions, with young adults showing more activation than older adults. Increased activation in young, compared to older adults, was also found for sustained PM activation in the IFG. These results provide new evidence that PM relies on dissociable transient and sustained cognitive processes, and that age-related deficits in PM can be explained by an inability to recruit PM-related brain networks in old age.

Background: Although Attention Deficit-Hyperactivity Disorder (ADHD) is a common mental disorder among adults, until recently, it was seldom diagnosed in adults. The significance of this disorder as a disease afflicting adults is increasing on a daily basis due to the complications associated with it such as disrupting occupational and educational functionality, as well as increasing the probability of drug abuse among those suffering from it. Objectives: With due regard to the significance of the subject. This study was conducted with the purpose of investigating the ADHD symptoms exhibited by students at Zahedan University of Medical Sciences. Patients and Methods: The present investigation is a descriptive-analytical study conducted at Zahedan Universitsy of Medical Sciences. The consensus sampling method was implemented to a sample volume consisting of 1000 persons. Based on the goals set in this research, two questionnaires were presented to the students to be completed arbitrarily: the demographic questionnaire and the Conners Adult ADHD Rating Scale Screening Version (CAARS-O:SV) questionnaire. The obtained information was then fed as input to the SPSS Software for analysis. Results: Of the 1000 questionnaires, 913 were completely answered by participants: 589 (64.5%) by female and 324 (35.5%) by male students. The average age of the participants was 21.7 ± 3.2. About 8% of the students reported drug abuse during the previous month. Compared with the symptom-free group, 27.1% in the inattention group, 30.3% in the hyperactivity group, 28.1% in the impulsiveness group, and 36.7% in the self-image problem group mentioned cases of drug abuse. Conclusions: The obtained results seem to indicate frequent occurrences of ADHD symptoms among the students. This requires further clinical evaluation and, if possible, diagnosis and consequent medical treatment for preventing the loss of educational performance or possible drug abuse, as well as decreasing impulsiveness.

Facial cues, such as a person's age, provide important information for social interactions. Processing such facial cues can be affected by observer bias. However, there is currently no consensus regarding how the brain is processing facial cues related to age, and if facial age processing changes as a function of the age of the observer (i.e., own-age bias). The primary study aim was to investigate functional networks involved in processing own-age vs. other-age faces among younger and older adults and determine how emotional expression of the face modulates own-age vs. other-age face processing. The secondary study aim was to examine the relation between higher social cognitive processes (i.e., empathy) and modulation of brain activity by facial age and emotional expression. During functional magnetic resonance imaging (fMRI) younger and older participants were asked to recognize happy, angry, and neutral expressions in own-age and other-age faces. Functional connectivity analyses with the amygdala as seed showed that for own-age faces both age groups recruited a network of regions including the anterior cingulate and anterior insula that was involved in empathy and detection of salient information. Brain-behavior analyses furthermore showed that empathic responses in younger, but not in older, participants were positively correlated with engagement of the medial prefrontal cortex during processing of angry own-age faces. These findings identify the neurobehavioral correlates of facial age processing, and its modulation by emotion expression, and directly link facial cue processing to higher-order social cognitive functioning.

Age-related declines in attention and working memory (WM) are well documented and may be worsened by the occurrence of distracting information. Emotionally valenced stimuli may have particularly strong distracting effects on cognition. We investigated age-related differences in emotional distraction using task-fMRI. WM performance in older adults was lower for emotional compared with neutral distractors, suggesting a disproportional impairment elicited by emotional task-irrelevant information. Critically, older adults were particularly distracted by task-irrelevant positive information, whereas the opposite pattern was found for younger adults. Age groups differed markedly in the brain response to emotional distractors; younger adults activated posterior cortical regions and the striatum, and older adults activated frontal regions. Also, an age by valence interaction was found for IFG and ACC, suggesting differential modulation of attention to task-relevant emotional information. These results provide new insights into age-related changes in emotional processing and the ability to resolve interference from emotional distraction. Electronic supplementary material The online version of this article (10.3758/s13415-018-0610-8) contains supplementary material, which is available to authorized users.

Eye-gaze direction plays a fundamental role in the perception of facial features and particularly the processing of emotional facial expressions. Yet, the neural underpinnings of the integration of eye gaze and emotional facial cues are not well understood. The primary aim of this study was to delineate the functional networks that subserve the recognition of emotional expressions as a function of eye gaze. Participants were asked to identify happy, angry, or neutral faces, displayed with direct or averted gaze, while their neural responses were measured with fMRI. The results showed that recognition of happy expressions, irrespective of eye-gaze direction, engaged the critical nodes of the default mode network. Recognition of angry faces, on the other hand, was gaze-dependent, engaging the critical nodes of the salience network when presented with direct gaze, but fronto-parietal areas when presented with averted gaze. Functional connectivity analysis further showed gaze-dependent engagement of a large-scale network connected to bilateral amygdala during the recognition of angry expressions. This study provides important insights into the functional connectivity between the amygdala and other critical social-cognitive brain nodes, which are essential in processing of ambiguous, potentially threatening social signals. These findings have implications for psychiatric disorders, such as post-traumatic stress disorder, which are characterized by aberrant limbic connectivity.