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Introduction: Artificial arterio-venous fistula-induced steal syndrome and subsequent distal ischemia are one of the most serious complications of arterial-venous fistula (AVF) surgery, ranging from 1 to 8% of cases. Traditionally, the complication is difficult to treat without losing the fistula. Treatment options include ligature of the fistula, fistula banding, distal revascularization with interval ligation (DRIL), proximalisation of the arterial inflow (PAI), and revision using distal inflow (RUDI). We would like to present a case of a 45-year-old woman who has developed dialysis associated steal syndrome with necrosis on the left arm 5 months after a cubital AVF was created. In order to maintain her arterio-venous fistula, RUDI procedure was performed to eliminate ischemia. We used basilic vein graft for distal revision of the astomosis. As a result of the procedure, ischemic complaints ceased, dialysis did not need to be interrupted, no further vascular access was necessary. Distalization of arterial inflow (RUDI) is an easy-to-implement, good-performing method for which the use of vena basilica graft is a very obvious solution.
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Derivación Arteriovenosa Quirúrgica , Oclusión de Injerto Vascular , Trasplantes , Femenino , Humanos , Ligadura , Persona de Mediana Edad , Diálisis Renal , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento , VenasRESUMEN
In earlier work we showed that individuals learn the spatial regularities within contexts and use this knowledge to guide detection of threatening targets embedded in these contexts. While it is highly adaptive for humans to use contextual learning to detect threats, it is equally adaptive for individuals to flexibly readjust behaviour when contexts once associated with threatening stimuli begin to be associated with benign stimuli, and vice versa. Here, we presented face targets varying in salience (threatening or non-threatening) in new or old spatial configurations (contexts) and changed the target salience (threatening to non-threatening and vice versa) halfway through the experiment to examine if contextual learning changes with the change in target salience. Detection of threatening targets was faster in old than new configurations and this learning persisted even after the target changed to non-threatening. However, the same pattern was not seen when the targets changed from non-threatening to threatening. Overall, our findings show that threat detection is driven not only by stimulus properties as theorised traditionally but also by the learning of contexts in which threatening stimuli appear, highlighting the importance of top-down factors in threat detection. Further, learning of contexts associated with threatening targets is robust and speeds detection of non-threatening targets subsequently presented in the same context.
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Atención/fisiología , Expresión Facial , Miedo/psicología , Aprendizaje/fisiología , Memoria/fisiología , Adulto , Cara , Femenino , Humanos , Masculino , Estimulación Luminosa/métodos , Adulto JovenRESUMEN
There is considerable variation in negative and positive symptoms of psychosis, global functioning, and emotional face perception (EFP), not only in schizophrenia but also in other psychotic disorders and healthy individuals. However, EFP impairment and its association with worse symptoms and global functioning have been examined largely in the domain of schizophrenia. The present study adopted a dimensional approach to examine the association of behavioral and neural measures of EFP with symptoms of psychosis and global functioning across individuals with schizophrenia spectrum (SZ; N = 28) and other psychotic (OP; N = 29) disorders, and never-psychotic participants (NP; N = 21). Behavioral and functional MRI data were recorded as participants matched emotional expressions of faces and geometrical shapes. Lower accuracy and increased activity in early visual regions, hippocampus, and amygdala during emotion versus shape matching were associated with higher negative, but not positive, symptoms and lower global functioning, across all participants. This association remained even after controlling for group-related (SZ, OP, and NP) variance, dysphoria, and antipsychotic medication status, except in amygdala. Furthermore, negative symptoms mediated the relationship between behavioral and brain EFP measures and global functioning. This study provides some of the first evidence supporting the specific relationship of EFP measures with negative symptoms and global functioning across psychotic and never-psychotic samples, and transdiagnostically across different psychotic disorders. Present findings help bridge the gap between basic EFP-related neuroscience research and clinical research in psychosis, and highlight EFP as a potential symptom-specific marker that tracks global functioning. (PsycINFO Database Record
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Encéfalo/fisiopatología , Emociones/fisiología , Reconocimiento Facial/fisiología , Trastornos Psicóticos/fisiopatología , Adulto , Estudios de Casos y Controles , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Trastornos Psicóticos/diagnósticoRESUMEN
Research on the perceptual prioritization of threatening stimuli has focused primarily on the physical characteristics and evolutionary salience of these stimuli. However, perceptual decision-making is strongly influenced by prestimulus factors such as goals, expectations, and prior knowledge. Using both event-related potentials and functional magnetic resonance imaging, we test the hypothesis that prior threat-related information and related increases in prestimulus brain activity play a key role in subsequent threat-related perceptual decision-making. After viewing threatening and neutral cues, participants detected perceptually degraded threatening and neutral faces presented at individually predetermined perceptual thresholds in a perceptual decision-making task. Compared with neutral cues, threat cues resulted in (1) improved perceptual sensitivity and faster detection of target stimuli; (2) increased late positive potential (LPP) and superior temporal sulcus (STS) activity, both of which are measures of emotional face processing; and (3) increased amygdala activity for subsequently presented threatening versus and neutral faces. Importantly, threat cue-related LPP and STS activity predicted subsequent improvement in the speed and precision of perceptual decisions specifically for threatening faces. Present findings establish the importance of top-down factors and prestimulus neural processing in understanding how the perceptual system prioritizes threatening information.
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Conducta/fisiología , Encéfalo/fisiología , Percepción/fisiología , Electroencefalografía , Potenciales Evocados/fisiología , Miedo/psicología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Adulto JovenRESUMEN
The rostral-ventral subdivision of the anterior cingulate cortex (rACC) plays a key role in the regulation of emotional processing. Although rACC has strong anatomical connections with anterior insular cortex (AIC), amygdala, prefrontal cortex and striatal brain regions, it is unclear whether the functional connectivity of rACC with these regions changes when regulating emotional processing. Furthermore, it is not known whether this connectivity changes with deficits in emotion regulation seen in different kinds of anxiety and depression. To address these questions regarding rACC functional connectivity, non-patients high in self-reported anxious apprehension (AP), anxious arousal (AR), anhedonic depression (AD) or none (CON) indicated the ink color of pleasant, neutral and unpleasant words during functional magnetic resonance imaging. While ignoring task-irrelevant unpleasant words, AD and CON showed an increase in the functional connectivity of rACC with AIC, putamen, caudate and ventral pallidum. There was a decrease in this connectivity in AP and AR, with AP showing greater reduction than AR. These findings provide support for the role of rACC in integrating interoceptive, emotional and cognitive functions via interactions with insula and striatal regions during effective emotion regulation in healthy individuals and a failure of this integration that may be specific to anxiety, particularly AP.
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Emociones/fisiología , Giro del Cíngulo/fisiopatología , Red Nerviosa/fisiopatología , Adolescente , Amígdala del Cerebelo/fisiopatología , Trastornos de Ansiedad/fisiopatología , Mapeo Encefálico , Corteza Cerebral/fisiopatología , Cognición/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Corteza Prefrontal/fisiopatología , Adulto JovenRESUMEN
It is hypothesised that threatening stimuli are detected better due to their salience or physical properties. However, these stimuli are typically embedded in a rich context, motivating the question whether threat detection is facilitated via learning of contexts in which threat stimuli appear. To address this question, we presented threatening face targets in new or old spatial configurations consisting of schematic faces and found that detection of threatening targets was faster in old configurations. This indicates that individuals are able to learn regularities within visual contexts and use this contextual information to guide detection of threatening targets. Next, we presented threatening and non-threatening face targets embedded in new or old spatial configurations. Detection of threatening targets was facilitated in old configurations, and this effect was reversed for non-threatening targets. Present findings show that detection of threatening targets is driven not only by stimulus properties as theorised traditionally but also by learning of contexts in which threatening stimuli appear. Further, results show that context learning for threatening targets obstructs context learning for non-threatening targets. Overall, in addition to typically emphasised bottom-up factors, our findings highlight the importance of top-down factors such as context and learning in detection of salient, threatening stimuli.
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Miedo/psicología , Aprendizaje , Detección de Señal Psicológica , Expresión Facial , Femenino , Humanos , Masculino , Estimulación Luminosa , Tiempo de Reacción , Adulto JovenRESUMEN
Deficits in working memory (WM) and emotion processing are prominent impairments in psychotic disorders, and have been linked to reduced quality of life and real-world functioning. Translation of knowledge regarding the neural circuitry implementing these deficits into improved diagnosis and targeted treatments has been slow, possibly because of categorical definitions of disorders. Using the dimensional Research Domain Criteria (RDoC) framework, we investigated the clinical and practical utility of transdiagnostic behavioral and neural measures of emotion-related WM disruption across psychotic disorders. Behavioral and functional MRI data were recorded while 53 participants with psychotic disorders and 29 participants with no history of psychosis performed a modified n-back task with fear and neutral distractors. Hierarchical regression analyses showed that psychotic symptoms entered after diagnosis accounted for unique variance in fear versus neutral accuracy and activation in the ventrolateral, dorsolateral, and dorsomedial prefrontal cortex, but diagnostic group entered after psychotic symptoms did not. These results remained even after controlling for negative symptoms, disorganized symptoms, and dysphoria. Finally, worse accuracy and greater prefrontal activity were associated with poorer social functioning and unemployment across diagnostic groups. Present results support the transdiagnostic nature of behavioral and neuroimaging measures of emotion-related WM disruption as they relate to psychotic symptoms, irrespective of diagnosis. They also provide support for the practical utility of these markers in explaining real-world functioning. Overall, these results elucidate key aspects of the RDoC construct of WM maintenance by clarifying its transdiagnostic importance and clinical utility in psychotic disorders. (PsycINFO Database Record
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Encéfalo/fisiopatología , Cognición/fisiología , Emociones/fisiología , Memoria a Corto Plazo/fisiología , Trastornos Psicóticos/diagnóstico , Trastornos Psicóticos/fisiopatología , Adulto , Mapeo Encefálico , Miedo/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Corteza Prefrontal/fisiopatología , Escalas de Valoración PsiquiátricaRESUMEN
Distracting emotional information impairs attention more in schizophrenia (SCZ) than in never-psychotic individuals. However, it is unclear whether this impairment and its neural circuitry is indicative generally of psychosis, or specifically of SCZ, and whether it is even more specific to certain SCZ symptoms (eg, deficit syndrome). It is also unclear if this abnormality contributes to impaired behavioral performance and real-world functioning. Functional imaging data were recorded while individuals with SCZ, bipolar disorder with psychosis (BDP) and no history of psychotic disorders (CON) attended to identity of faces while ignoring their emotional expressions. We examined group differences in functional connectivity between amygdala, involved in emotional evaluation, and sub-regions of medial prefrontal cortex (MPFC), involved in emotion regulation and cognitive control. Additionally, we examined correlation of this connectivity with deficit syndrome and real-world functioning. Behaviorally, SCZ showed the worst accuracy when matching the identity of emotional vs neutral faces. Neurally, SCZ showed lower amygdala-MPFC connectivity than BDP and CON. BPD did not differ from CON, neurally or behaviorally. In patients, reduced amygdala-MPFC connectivity during emotional distractors was related to worse emotional vs neutral accuracy, greater deficit syndrome severity, and unemployment. Thus, reduced amygdala-MPFC functional connectivity during emotional distractors reflects a deficit that is specific to SCZ. This reduction in connectivity is associated with worse clinical and real-world functioning. Overall, these findings provide support for the specificity and clinical utility of amygdala-MPFC functional connectivity as a potential neural marker of SCZ.
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Amígdala del Cerebelo/fisiopatología , Atención/fisiología , Trastorno Bipolar/fisiopatología , Conectoma/métodos , Emociones/fisiología , Función Ejecutiva/fisiología , Corteza Prefrontal/fisiopatología , Esquizofrenia/fisiopatología , Adolescente , Adulto , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
The importance of top-down factors such as goals and expectations is well-established in both visual perception and anxiety. However, researchers have attributed the perceptual prioritization of threatening stimuli in anxiety to bottom-up, automatic processing of these stimuli while neglecting the role of prestimulus, top-down factors. Furthermore, different kinds of anxiety (dispositional versus induced) impact cognitive functions differently, suggesting that top-down factors may have distinct effects on threat perception. In the present study, we examined whether prestimulus representations of threatening stimuli facilitate perception differently, depending on induced and trait anxiety. Two groups of participants completed a cued discrimination task using threatening or neutral cues to identify subsequently presented fearful and neutral faces, degraded to each participant's perceptual threshold. In Group 1, threat of shock induced anxiety (n = 22; 12 men), whereas in Group 2, no anxiety was induced (n = 29; 7 men). The impact of induced anxiety on perception interacted with trait anxiety. Following fear cues, higher trait anxiety was associated with improved perceptual sensitivity and faster reaction time under threat of shock, and worse perceptual sensitivity and slower reaction time in absence of shock. The present findings represent an important advance in the literature because they elucidate the role of previously ignored top-down factors in threat perception for individuals with varying levels of anxiety and highlight the distinct impact that different types of anxiety have on the perception of threatening stimuli. Furthermore, these findings underline the importance of including top-down factors in future conceptualizations of perceptual bias toward threat in anxiety.