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Stress is an inevitable element of everyday living. Developmental studies suggested that adolescents are more vulnerable and sensitive to the effect of stress due to their developing brains, especially in areas related to stress perception and processing. This voxel-based morphometry study examined the association between various neurobiological markers and the level of perceived stress experienced by adolescents (n = 26) and middle-aged adults (n = 26). Our findings indicated that differences existed in the relationships between perceived stress and the structural volume of the orbitofrontal cortex (OFC) extending to the insula and amygdala. Specifically, the levels of perceived stress and the grey matter volume of the orbitofrontal cortex, the insula, and the amygdala were positively related in adolescents but negatively related for adults. Furthermore, a significant negative correlation between perceived stress and cortisol levels was observed in adults, whereas the relationship between perceived stress and cortisol levels was not significant for adolescents. Perceived stress measurement may be better than cortisol levels in terms of reflecting the emotional states of adolescents. In sum, the relationships between perceived stress and neurobiological markers were different between adolescents and middle-aged adults and thus appeared to be age dependent.

Our brain during distinct developmental phases may show differential responses to perceived psychological stress, yet existing research specifically examining neurodevelopmental changes in stress processing is scarce. To fill in this research gap, this functional magnetic resonance imaging (fMRI) study examined the relationship between perceived stress and resting-state neural connectivity patterns among 67 healthy volunteers belonging to three age groups (adolescents, young adults and adults), who were supposed to be at separate neurodevelopmental phases and exhibit different affect regulatory processes in the brain. While the groups showed no significant difference in self-reported general perceived stress levels, the functional connectivity between amygdala and ventromedial prefrontal cortex (vmPFC) was positively and negatively correlated with perceived stress in adolescents and young adults respectively, while no significant correlations were observed in adults. Furthermore, among adolescents, the causal functional interaction between amygdala and vmPFC exhibited bottom-up connectivity, and that between amygdala and subgenual anterior cingulate cortex exhibited top-down connectivity, both of which changed to bilateral directions, i.e. both bottom-up and top-down connections, in both young adults and adults, supporting the notion that the amygdala and prefrontal cortical circuitries undergo functional reorganizations during brain development. These novel findings have important clinical implications in treating stress-related affective disorders in young individuals., Highlights • Age moderates the relationship between prefrontal-amygdala circuitry and perceived stress. • The VMPFC-amygdala connectivity were distinct in different age groups. • The VMPFC-amygdala connectivity was positively related to stress in adolescents. • The VMPFC-amygdala connectivity was negatively related to stress in young adults. • The Ventral PFC-amygdala connectivity was bi-directional in adults.

Highlights • PSD patients showed GMV decreases in the left MFG. • Change of the MFG's GMV is independent from the lesions. • Hypoactivity in IFG and DLPFC may account for the PSD symptoms. • PSD patients may have difficulty in understanding and appraising negative emotions., Stroke survivors are known to suffer from post-stroke depression (PSD). However, the likelihood of structural changes in the brains of PSD patients has not been explored. This study aims to extract changes in the gray matter of these patients and test how these changes account for the PSD symptoms. High-resolution T1 weighted images were collected from 23 PSD patients diagnosed with subcortical stroke. Voxel-based morphometry and support vector machine analyses were used to analyze the data. The results were compared with those collected from 33 non-PSD patients. PSD group showed decreased gray matter volume (GMV) in the left middle frontal gyrus (MFG) when compared to the non-PSD patients. Together with the clinical and demographic variables, the MFG's GMV predictive model was able to distinguish PSD from the non-PSD patients (0•70 sensitivity and 0•88 specificity). The changes in the left inferior frontal gyrus (61%) and dorsolateral prefrontal cortex (39%) suggest that the somatic/affective symptoms in PSD is likely to be due to patients’ problems with understanding and appraising negative emotional stimuli. The impact brought by the reduced prefrontal to limbic system connectivity needs further exploration. These findings indicate possible systemic involvement of the frontolimbic network resulting in PSD after brain lesions which is likely to be independent from the location of the lesion. The results inform specific clinical interventions to be provided for treating depressive symptoms in post-stroke patients.

Background: Neuroplastic underpinnings of meditation-induced changes in affective processing are largely unclear. Methods: We included healthy older participants in an active-controlled experiment. They were involved a meditation training or a control relaxation training of eight weeks. Associations between behavioral and neural morphometric changes induced by the training were examined. Results: The meditation group demonstrated a change in valence perception indexed by more neutral valence ratings of positive and negative affective images. These behavioral changes were associated with synchronous structural enlargements in a prefrontal network involving the ventromedial prefrontal cortex and the inferior frontal sulcus. In addition, these neuroplastic effects were modulated by the enlargement in the inferior frontal junction. In contrast, these prefrontal enlargements were absent in the active control group, which completed a relaxation training. Supported by a path analysis, we propose a model that describes how meditation may induce a series of prefrontal neuroplastic changes related to valence perception. These brain areas showing meditation-induced structural enlargements are reduced in older people with affective dysregulations. Conclusion: We demonstrated that a prefrontal network was enlarged after eight weeks of meditation training. Our findings yield translational insights in the endeavor to promote healthy aging by means of meditation.

The in vivo neural activity of the pons during the perception of affective stimuli has not been studied despite the strong implications of its role in affective processing. To examine the activity of the pons during the viewing of affective stimuli, and to verify its functional and structural connectivity with other affective neural correlates, a multimodal magnetic resonance imaging methodology was employed in this study. We observed the in vivo activity of the pons when viewing affective stimuli. Furthermore, small-world connectivity indicated that the functional connectivity (FC) between the pons and the cortico-limbic affective regions was meaningful, with the coefficient λ being positively associated with self-reported emotional reactivity. The FC between the pons and the cortico-limbic-striatal areas was related to self-reported negative affect. Corroborating this finding was the observation that the tract passing through the pons and the left hippocampus was negatively related to self-reported positive affect and positively correlated with emotional reactivity. Our findings support the framework that the pons works conjunctively with the distributed cortico-limbic-striatal systems in shaping individuals' affective states and reactivity. Our work paves the path for future research on the contribution of the pons to the precipitation and maintenance of affective disorders.

Background. Oxford Cognitive Screen is designed for assessing cognitive functions of poststroke patients. This study was aimed to assess the psychometric properties of the Chinese (Putonghua) version of the Oxford Cognitive Screen-Putonghua (OCS-P) for use among poststroke patients without neglect. Methods. Expert review panel evaluated content validity of the Chinese-translated items. After pilot tested the translated items, the patients and healthy participants completed the OCS-P as well as the Montreal Cognitive Assessment (MoCA-ChiB) and Goldenberg’s test. A group of patients completed OCS-P for the second time within seven days. Data analyses included confirmatory factor analysis, item difficulty and item-total correlation, inter- and intrarater reliability, internal consistency, and between-group discrimination. Results. One hundred patients and 120 younger (n=60) or older (n=60) healthy participants completed all the tests. Modifications were required for items in the “Picture Naming”, “Orientation”, and “Sentence Reading” subscales. Confirmatory factor analysis revealed a three-factor structure for the OCS-P subscales. The internal consistency coefficients for the three identified test dimensions were 0.30 to 0.52 (Cronbach’s alpha). Construct validity coefficients between the OCS-P and MoCA-ChiB subscales were 0.45 < r < 0.79 (p<0.001) and the “Praxis” subscale of OCS-P and Goldenberg’s test was r=0.72 (p<0.001). The interrater reliability coefficients for the subscales were in general higher than the intrarater reliability coefficients. The “Picture Naming” and “Numerical Cognition” subscales were the most significant (p=0.003) for differentiating patient participants from their older healthy counterpart. Conclusion. This study generated satisfactory evidence on the content validity, substantive validity, construct validity, inter- and intrarater reliability, and known-group discrimination of the OCS-P. They support its application among poststroke patients who speak Putonghua. Future studies could review the existing five-dimension domains for improving its structural validity and internal consistency as well as generate evidence of the OCS-P for use among the poststroke patients with neglect.

Comparing early- and late-onset blindness in individuals offers a unique model for studying the influence of visual experience on neural processing. This study investigated how prior visual experience would modulate auditory spatial processing among blind individuals. BOLD responses of early- and late-onset blind participants were captured while performing a sound localization task. The task required participants to listen to novel “Bat-ears” sounds, analyze the spatial information embedded in the sounds, and specify out of 15 locations where the sound would have been emitted. In addition to sound localization, participants were assessed on visuospatial working memory and general intellectual abilities. The results revealed common increases in BOLD responses in the middle occipital gyrus, superior frontal gyrus, precuneus, and precentral gyrus during sound localization for both groups. Between-group dissociations, however, were found in the right middle occipital gyrus and left superior frontal gyrus. The BOLD responses in the left superior frontal gyrus were significantly correlated with accuracy on sound localization and visuospatial working memory abilities among the late-onset blind participants. In contrast, the accuracy on sound localization only correlated with BOLD responses in the right middle occipital gyrus among the early-onset counterpart. The findings support the notion that early-onset blind individuals rely more on the occipital areas as a result of cross-modal plasticity for auditory spatial processing, while late-onset blind individuals rely more on the prefrontal areas which subserve visuospatial working memory.

Human brains are highly plastic throughout the life­span, even after brain injuries. The possible modulation of functions due to neural plasticity in various brain regions contributes to the learning and adaptation of unlearnt as well as new behaviors. Over the past decade, research on brain-behavior relationships has grown exponentially. In addition to behavioral assessments, electrophysiology and neuroimaging methods have been widely used to examine the neural networks, structural and functional abnormalities, and the effects of the therapeutic training in aged adults or individuals with neurological disorders. The five contributions to this special issue address the relationships between brain and behavior and have implications for present and future research and practice in neurorehabilitation.

Recognizing familiar faces is essential to social functioning, but little is known about how people identify human faces and classify them in terms of familiarity. Face identification involves discriminating familiar faces from unfamiliar faces, whereas face classification involves making an intentional decision to classify faces as 'familiar' or 'unfamiliar.' This study used a directed-lying task to explore the differentiation between identification and classification processes involved in the recognition of familiar faces. To explore this issue, the participants in this study were shown familiar and unfamiliar faces. They responded to these faces (i.e., as familiar or unfamiliar) in accordance with the instructions they were given (i.e., to lie or to tell the truth) while their EEG activity was recorded. Familiar faces (regardless of lying vs. truth) elicited significantly less negative-going N400f in the middle and right parietal and temporal regions than unfamiliar faces. Regardless of their actual familiarity, the faces that the participants classified as 'familiar' elicited more negative-going N400f in the central and right temporal regions than those classified as 'unfamiliar.' The P600 was related primarily with the facial identification process. Familiar faces (regardless of lying vs. truth) elicited more positive-going P600f in the middle parietal and middle occipital regions. The results suggest that N400f and P600f play different roles in the processes involved in facial recognition. The N400f appears to be associated with both the identification (judgment of familiarity) and classification of faces, while it is likely that the P600f is only associated with the identification process (recollection of facial information). Future studies should use different experimental paradigms to validate the generalizability of the results of this study., published_or_final_version

r r Abstract: Cross-modal processing enables the utilization of information received via different sensory organs to facilitate more complicated human actions. We used functional MRI on early-blind individuals to study the neural processes associated with cross auditory-spatial learning. The auditory signals, con- verted from echoes of ultrasonic signals emitted from a navigation device, were novel to the participants. The subjects were trained repeatedly for 4 weeks in associating the auditory signals with different distan- ces. Subjects' blood-oxygenation-level-dependent responses were captured at baseline and after training using a sound-to-distance judgment task. Whole-brain analyses indicated that the task used in the study involved auditory discrimination as well as spatial localization. The learning process was shown to be mediated by the inferior parietal cortex and the hippocampus, suggesting the integration and binding of auditory features to distances. The right cuneus was found to possibly serve a general rather than a spe- cific role, forming an occipital-enhanced network for cross auditory-spatial learning. This functional net- work is likely to be unique to those with early blindness, since the normal-vision counterparts shared activities only in the parietal cortex. Hum Brain Mapp 00:000-000, 2011. V C 2011 Wiley-Liss, Inc.

Objective To investigate how family members' attitudes toward functional regain, and patients' knowledge and intention of independence influence poststroke rehabilitation. Design Cross-sectional study. Setting Three rehabilitation inpatient settings. Participants Younger (n=79) and older (n=84) poststroke patients, along with their family members (spouses, n=104; children, n=59). Interventions Not applicable. Main Outcome Measures Custom-designed questionnaires were used to tap into the patients' knowledge about rehabilitation (Patient's Rehabilitation Questionnaire–Knowledge About Rehabilitation) and intention of independence (Patient's Rehabilitation Questionnaire–Intention of Independence), and family members' attitudes toward patients in performing basic activities of daily living (BADL) (Family Member Attitudes Questionnaire–BADL) and instrumental activities of daily living (Family Member Attitudes Questionnaire–instrumental activities of daily living). The rehabilitation outcomes included gains in motor, cognitive, and emotional functions, and self-care independence, measured with common clinical instruments. Results The Family Member Attitudes Questionnaire–BADL predicted cognitive outcome and the Patient's Rehabilitation Questionnaire–Intention of Independence predicted motor outcome for both groups. Differential age-related effects were revealed for the Patient's Rehabilitation Questionnaire–Intention of Independence in predicting emotional outcome only for the younger group, and self-care independence only for the older group. Conclusions Patients' intention of independence positively affected motor recovery, while family members' positive attitudes promoted cognitive regain. The findings suggested plausible age-related differences in how patients' intentions affect emotion versus self-care independence outcomes. Future studies should explore strategies for promoting positive attitudes toward independence among patients and family members during poststroke rehabilitation.