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81.
Similar to adults with schizophrenia, youth at high risk for developing schizophrenia present difficulties in recognizing emotions in faces. These difficulties might index vulnerability for schizophrenia and play a role in the development of the illness. Facial emotion recognition (FER) impairments have been implicated in declining social functioning during the prodromal phase of illness and are thus a potential target for early intervention efforts. This study examined 9- to 14-year-old children: 34 children who presented a triad of well-replicated antecedents of schizophrenia (ASz), including motor and/or speech delays, clinically relevant internalizing and/or externalizing problems, and psychotic-like experiences (PLEs), and 34 typically developing (TD) children who presented none of these antecedents. An established FER task (ER40) was used to assess correct recognition of happy, sad, angry, fearful, and neutral expressions, and facial emotion misperception responses were made for each emotion type. Relative to TD children, ASz children presented an overall impairment in FER. Further, ASz children misattributed neutral expressions to face displaying other emotions and also more often mislabeled a neutral expression as sad compared with healthy peers. The inability to accurately discriminate subtle differences in facial emotion and the misinterpretation of neutral expressions as sad may contribute to the initiation and/or persistence of PLEs. Interventions that are effective in teaching adults to recognize emotions in faces could potentially benefit children presenting with antecedents of schizophrenia.Key words: emotion recognition, high risk, child and adolescent psychopathology, social functioning, psychotic-like experiencesPeople with schizophrenia display a marked impairment in recognizing emotions in the faces of others, particularly anger, sadness, and fear, and less difficulty recognizing happy expressions.1,2 Facial emotion recognition (FER) difficulties are associated with poor social functioning3 and have implications for the development, course, and outcome of the disorder.4 Yet, interventions to improve FER performance (eg, Training of Affect Recognition)5 can reduce these deficits and elicit generalized improvement in other social cognitive domains.6FER impairments are apparent not only among individuals with chronic schizophrenia (for review see Kohler et al 2010)2 but also among individuals experiencing a first episode of psychosis7,8 and among unaffected adolescent (though only for neutral facial expressions)9 and adult first-degree relatives of individuals with schizophrenia.10 Thus, abnormalities in FER are present at illness onset and may also index vulnerabil ity for schizophrenia. Prospective studies following individuals at elevated risk for developing schizophrenia are needed to determine the extent to which impairments of FER precede illness and represent potential targets for early intervention. Among symptomatic, help-seeking individuals meeting ultra-high risk (UHR) criteria for psychosis,7,8,11–13 evidence for FER impairments is mixed. Two studies reported FER impairments relative to healthy participants,7,11 while another study indicated specific difficulties in correctly identifying neutral expressions.13 A study of a large British birth cohort comprising 5267 children reported no association between FER at 8 years and subclinical psychotic symptoms at 12 years.14 By contrast, a recent cross-sectional study of 748 children aged 10–13 years indicated that those reporting psychotic-like experiences (PLEs) on questionnaires were poorer at recognizing facial emotional expressions, primarily sadness.15 Unfortunately, as with many previous FER studies, no information was provided about the nature of the facial emotion misperceptions committed when processing facial expressions. Though PLEs in childhood are significantly associated with later psychotic illness,16,17 they are also associated with an increased risk of anxiety disorders16 and other psychiatric disorders including affective disorders, drug use disorders, and personality disorders,18 albeit to a lesser extent. Thus, PLEs constitute a relatively nonspecific marker of risk for subsequent psychiatric disorders. Further, cross-sectional data from the general population indicate significant comorbidity of PLEs with emotional and behavioral problems,19,20 implying that the observed relationship between PLEs and FER reported by Roddy et al15 might reflect the presence of unreported internalizing and/or externalizing psychopathology.To better characterize the nature of FER associated with schizophrenia, several studies have examined facial emotion misperceptions. Relative to healthy adults, individuals with schizophrenia more often mislabel negative emotions to faces displaying no or neutral expressions.21,22 Adolescent relatives of individuals with schizophrenia, compared with adolescents from healthy families, also more often incorrectly label neutral expressions as displaying negative emotions, predominantly mislabeling them as sad.9 Among individuals with schizophrenia, and individuals at high risk for psychosis,23 functional imaging has revealed hyperactivation of the amygdala during the processing of neutral expressions, which could reflect emotional salience being assigned to neutral stimuli.24 It has been suggested that the tendency to misinterpret neutral facial expressions as displaying emotion may contribute to the development of positive symptoms in schizophrenia.23 Previous research indicates that facial emotion misperceptions might constitute the cognitive mechanism contributing to the social impairment that characterizes UHR samples13 and is a critical component to understanding FER difficulties in samples at risk for schizophrenia.Until recently, there has been no practical method for identifying children who are at elevated risk for schizophrenia. Despite the high heritability of schizophrenia, only approximately one-third of individuals with schizophrenia have a first- or second-degree relative with the illness. Consequently, a positive family history identifies only a subset of children who will develop the illness.25 Prospective investigations of birth cohorts have demonstrated consistently that, by middle childhood, individuals who later developed schizophrenia presented delays in motor and language development; disturbances in social, emotional, and behavioral functioning; and PLEs.17 Based on this evidence, we developed questionnaires, to be completed by children aged 9–12 years and their primary caregiver, to identify children who present a triad of these replicated antecedents of schizophrenia (ASz).26,27 We defined ASz to include (1) early speech and/or motor developmental delays/abnormalities; (2) social, emotional, and/or behavioral problems in the clinical range; and (3) PLEs. It is thought that the identification of children who present multiple antecedents of schizophrenia that have been replicated in prospective longitudinal studies will offer greater sensitivity and specificity for later development of schizophrenia than any one antecedent.We are currently following the development of ASz children to determine the specificity and sensitivity of the triad of antecedents for later schizophrenia development. We anticipate that some ASz children will develop schizophrenia and spectrum disorders, some will develop other disorders, and others will remain healthy. In the interim, our investigations have shown that ASz children, compared with typically developing (TD) children who present no antecedents and no family history of schizophrenia or a spectrum disorder, are characterized by features observed among adults with schizophrenia including (1) deficits in performance on standardized intelligence and neuropsychological tests of executive function and memory,28 (2) dyskinetic movement abnormalities,29 (3) reduction in the amplitude of the error-related negativity event-related potential component generated in the anterior cingulate that indexes internal monitoring of behavior,30 and (4) structural brain abnormalities in the superior/middle temporal gyri.31 Further, among children aged 9–12 years, two-thirds (69%) of those presenting with the triad of antecedents report distress and/or functional impairment associated with their PLEs.27This study sought to determine whether ASz children present FER difficulties similar to those reported among individuals with schizophrenia and at-risk youth, after accounting for intelligence quotient (IQ) differences between ASz and TD groups,28 which may contribute to FER performance. The study examined overall performance on FER tasks, as well as the specific nature of facial emotion misperceptions. We hypothesized that ASz children would be less accurate than TD children in identifying emotions in facial expressions and that they would more often mislabel neutral faces with other emotion expressions. In particular, we anticipated that ASz children would misidentify neutral expressions as sad, as was reported in a study of youth with family histories of schizophrenia using the same FER task.9  相似文献   
82.
83.
Comparing local neural structures across large sets of examples is crucial when studying gene functions, and their effect in the Drosophila brain. The current practice of aligning brain volume data to a joint reference frame is based on the neuropil. However, even after alignment neurons exhibit residual location and shape variability that, together with image noise, hamper direct quantitative comparison and retrieval of similar structures on an intensity basis. In this paper, we propose and evaluate an image-based retrieval method for neurons, relying on local appearance, which can cope with spatial variability across the population. For an object of interest marked in a query case, the method ranks cases drawn from a large data set based on local neuron appearance in confocal microscopy data. The approach is based on capturing the orientation of neurons based on structure tensors and expanding this field via Gradient Vector Flow. During retrieval, the algorithm compares fields across cases, and calculates a corresponding ranking of most similar cases with regard to the local structure of interest. Experimental results demonstrate that the similarity measure and ranking mechanisms yield high precision and recall in realistic search scenarios.  相似文献   
84.
85.
86.
We describe features of a patient that broadens the clinical and pathological spectrum of neurofilament inclusion disease (NFID). The patient was a 52-year-old man with a 5–6 year history of progressive, asymmetrical spastic weakness of the upper and lower extremities; l-DOPA-unresponsive parkinsonism; and SPECT evidence of asymmetrical frontoparietal and basal ganglia hypoperfusion. The brain had marked frontoparietal parasagittal cortical atrophy, including the motor cortex, with histopathological evidence of neurofilament- and -internexin-immunoreactive neuronal inclusions. The corticospinal tract had degeneration, but there was minimal lower motor neuron pathology. There was also severe neuronal loss and gliosis in the posterolateral putamen and the substantia nigra, mimicking multiple system atrophy; however, glial cytoplasmic inclusions were not detected with -synuclein immunohistochemistry. This case extends the clinical and pathological spectrum of NFID to include cases with predominant parkinsonian and pyramidal features.Gerry Shaw holds equity in EnCor Biotechnology Inc., a company commercializing the alpha-internexin antibody used in this study, and may benefit by receiving royalties or equity growth.  相似文献   
87.
The focus of the investigation was the relationship between intellectual function, as measured by the Satz-Mogel WAIS-R, and performance on the Benton Visual Retention Test. One hundred and twenty subjects, aged 18 to 30 years, were divided, 20 each, by IQ level into groups ranging from Mentally Retarded to Superior. Subjects provided both Number Correct and Error Score performances under conditions of immediate (Administration A, Form C), 15 s delay (Administration D, Form D), 30 m delay (Form E-card 2, 6, and 10), and copy (Administration C, Form C). Significant group differences were evident at all three conditions, primarily at the lower IQ ranges. Performances of the Average, High Average, and Superior IQ groups differed little, suggesting a ceiling effect. Significant decrements is performance under 30 m delay were evident only within the Low Average, Average and Superior IQ groups. Finally, normative performances under Administration C (Copy, Form C) and a quantitative assessment of errors (Administrations A and D) were reported.  相似文献   
88.
Adenosine and its derivatives are important building blocks of the biological system. They serve as the universal energy currency, amplify intracellular signals for various signal transduction pathways, and can also be used as the co-substrates for enzymatic transformations. The synthesis and regulation of adenosine and its analogs rely on the adenosine binding proteins (ABPs). Dysregulated ABP activity contributes to numerous diseases such as cancer, metabolic disorders, and neurodegenerative diseases. Presently, there is intense interest in targeting ABPs for therapeutic purposes. A large fraction of the human ABP family remains poorly characterized. The need for innovative chemical probes to investigate ABP function in the native biological matrix is apparent. In this study, an adenosine analog, probe 1, with a photoaffinity group and biotin tag was synthesized using concise synthetic strategies. This probe was able to label and capture individual recombinant ABPs with good target selectivity. Probe 1 was also evaluated for its ability to label spiked ABP in complex cell lysates. This chemical probe, together with the labeling and enrichment assay, is of great value to interrogate the biological functions of ABPs and to elucidate their diversity under different physiological conditions.

Photoactivatable adenosine analog-enabled capture and enrichment of adenosine binding protein (ABP).  相似文献   
89.
Examined the California Psychological Inventory (CPI) profiles of peernominated assertives, unassertives, and aggressives. Eighty males from two social fraternities peer-nominated assertives, unassertives and aggressives. The nomination procedure yielded 12 nominees per group. A profile analysis of the CPI indicated that assertives and aggressives were significantly more similar than were assertives and unassertives, and unassertives and aggressives. Results of a subscale analysis indicated that assertives and aggressives were significantly higher on Dominance, Capacity for Status, Sociability, and Social Presence than Unassertives, but were not significantly different from each other on these subscales. Also, assertives were significantly higher on Socialization, Self-Control, and Achievement via Conformance than were aggressives. Finally, assertives were significantly higher on Achievement via Conformance than were unassertives and aggressives. Implications are discussed.  相似文献   
90.
The Assertion Inventory (AI) (Gambrill & Richey, 1975), a 40-item questionnaire, collects two types of information about assertive behavior: (a) degree of discomfort felt in specific situations; and (b) judged probability of engaging in a behavior. Ss are categorized into one of four groups: Assertive (low discomfort and high assertion), Unassertive (high discomfort and low assertion), Doesn't Care (low discomfort and low assertion), or Anxious Performer (high discomfort and high assertion). The purpose of the study was to validate the Al using a role-play format. Two experiments comprised the study. The Ss were 96 undergraduates (48 in Experiment 1 and 48 in Experiment 2). The AI scores were maximally representative of each Al category. The results of experiment 1 were congruent with inventory scores; the results of Experiment 2 were not. Potential consequences of social desirability and the use of role-play as an outcome measure are discussed.  相似文献   
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