Categoría: Papers con abstracts

Executive dysfunction may result from prefrontal circuitry involvement occurring in both neurodegenerative diseases and psychiatric disorders. Moreover, multiple neuropsychiatric conditions, may present with overlapping behavioral and cognitive symptoms, making differential diagnosis challenging, especially during earlier stages. In this sense, cognitive assessment may contribute to the differential diagnosis by providing an objective and quantifiable set of measures that has the potential to distinguish clinical conditions otherwise perceived in everyday clinical settings as quite similar. OBJECTIVE: The goal of this study was to investigate the utility of the INECO Frontal Screening (IFS) for differentiating bv-FTD patients from patients with Major Depression. METHODS: We studied 49 patients with bv-FTD diagnosis and 30 patients diagnosed with unipolar depression compared to a control group of 26 healthy controls using the INECO Frontal Screening (IFS), the Mini Mental State Examination (MMSE) and the Addenbrooke’s Cognitive Examination-Revised (ACE-R). RESULTS: Patient groups differed significantly on the motor inhibitory control (U=437.0, p<0.01), verbal working memory (U=298.0, p<0.001), spatial working memory (U=300.5, p<0.001), proverbs (U=341.5, p<0.001) and verbal inhibitory control (U=316.0, p<0.001) subtests, with bv-FTD patients scoring significantly lower than patients with depression. CONCLUSION: Our results suggest the IFS can be considered a useful tool for detecting executive dysfunction in both depression and bv-FTD patients and, perhaps more importantly, that it has the potential to help differentiate these two conditions.

Hierarchical predictive coding suggests that attention in humans emerges from increased precision in probabilistic inference, whereas expectation biases attention in favor of contextually anticipated stimuli. We test these notions within auditory perception by independently manipulating top-down expectation and attentional precision alongside bottom-up stimulus predictability. Our findings support an integrative interpretation of commonly observed electrophysiological signatures of neurodynamics, namely mismatch negativity (MMN), P300, and contingent negative variation (CNV), as manifestations along successive levels of predictive complexity. Early first-level processing indexed by the MMN was sensitive to stimulus predictability: here, attentional precision enhanced early responses, but explicit top-down expectation diminished it. This pattern was in contrast to later, second-level processing indexed by the P300: although sensitive to the degree of predictability, responses at this level were contingent on attentional engagement and in fact sharpened by top-down expectation. At the highest level, the drift of the CNV was a fine-grained marker of top-down expectation itself. Source reconstruction of high-density EEG, supported by intracranial recordings, implicated temporal and frontal regions differentially active at early and late levels. The cortical generators of the CNV suggested that it might be involved in facilitating the consolidation of context-salient stimuli into conscious perception. These results provide convergent empirical support to promising recent accounts of attention and expectation in predictive coding.

Vascular dementia (VaD) is one of the most prevalent causes of dementia, and it is frequently misdiagnosed and undertreated in clinical practice. Because neuropsychological outcome depends, among other factors, on the size and location of the vascular brain injury, characterizing the cognitive profile of VaD has been especially challenging. Yet, there has been sufficient evidence to show a marked impairment of attention and executive functions, in particular in relation to Alzheimer disease. Being able to detect these deficits at bedside is crucial for everyday clinical practice, and yet, brief cognitive screening toots such as the Mini-Mental Sate Examination (MMSE) may overlook at cognitive deficits typical of patients with VaD. The Addenbrooke’s Cognitive Examination Revised (ACE-R) is also a brief cognitive screening tool designed to incorporate the items of the MMSE and further extend the test to assess orientation, attention, verbal fluency, memory, language, and visuospatial abilities. In this study, we investigated the ability of the Spanish version of the ACE-R to detect the cognitive impairment showed in patients with subcortical ischemic vascular dementia, and we compared its usefulness to that of the MMSE in this population. Scores on these tests were compared to those of patients with Alzheimer disease and matched healthy controls. The 88-point cut-off proposed for the ACE-R was associated with a sensitivity of 100% and a specificity of 100% for the detection of cognitive impairment, demonstrating a stronger capacity than the MMSE (sensitivity of 42% with its 23-point cut-off score). We also found that the verbal fluency subtest of the ACE-R may be potentially useful in discriminating patients with subcortical ischemic vascular dementia from patients with AD. We discuss the utility of these findings in the context of everyday clinical practice and we propose that future studies should evaluate the potential usefulness of combining the ACE-R with a brief screening tool of executive functioning.

Individual differences in theory of mind (ToM) are affected by a variety of factors. We investigated the relationship between empathy, sex and fluid intelligence (FI) as predictors of ToM in a random probabilistic sample of secondary students. First, we explored whether sex, as well as high, average or low levels of empathy and FI affect ToM performance. Furthermore, we assessed the contribution of empathy, sex and FI in predicting ToM by using a path analysis. This method allows testing of causal models of directed dependencies among a set of variables. The causal dependencies of empathy, sex and fluid intelligence were confirmed and identified. In addition, the model confirmed the direct effect of empathy, sex and fluid intelligence on ToM; and the indirect effect of sex mediated by empathy. Thus, individual differences in ToM levels are partially attributable to sex, empathy and fluid intelligence variability, raising important considerations for clinical research as well as ToM‟s theoretical models of domain specificity.

We sought to investigate the decision making profile of Primary Progressive Aphasia (PPA) by assessing patients diagnosed with this disease (n = 10), patients diagnosed with behavioral variant frontotemporal dementia (bvFTD, n = 35), and matched controls (n = 14) using the Iowa Gambling Task, a widely used test that mimics real-life decision making. Participants were also evaluated with a complete neuropsychological battery. Patients with PPA were unable to adopt an advantageous strategy on the IGT, which resulted in a flat performance, different to that exhibited by both controls (who showed advantageous decision making) and bvFTD patients (who showed risk-appetitive behavior). The decision making profile of PPA patients was not associated with performance on language tasks and did not differ between sub-variants of the disease (namely, semantic dementia and progressive nonfluent aphasia). Investigating decision making in PPA is crucial both from a theoretical perspective, as it can shed light about the way in which language interacts with other cognitive functions, as well as a clinical standpoint, as it could lead to a more objective detection of impairments of decision making deficits in this condition.

Is it permissible to harm one to save many? Classic moral dilemmas are often defined by the conflict between a putatively rational response to maximize aggregate welfare (i.e., the utilitarian judgment) and an emotional aversion to harm (i.e., the non-utilitarian judgment). Here, we address two questions. First, what specific aspect of emotional responding is relevant for these judgments? Second, is this aspect of emotional responding selectively reduced in utilitarians or enhanced in non-utilitarians? The results reveal a key relationship between moral judgment and empathic concern in particular (i.e., feelings of warmth and compassion in response to someone in distress). Utilitarian participants showed significantly reduced empathic concern on an independent empathy measure. These findings therefore reveal diminished empathic concern in utilitarian moral judges.

BACKGROUND: The ability to integrate contextual information with social cues to generate social meaning is a key aspect of social cognition. It is widely accepted that patients with schizophrenia and bipolar disorders have deficits in social cognition; however, previous studies on these disorders did not use tasks that replicate everyday situations.

METHODOLOGY/PRINCIPAL FINDINGS: This study evaluates the performance of patients with schizophrenia and bipolar disorders on social cognition tasks (emotional processing, empathy, and social norms knowledge) that incorporate different levels of contextual dependence and involvement of real-life scenarios. Furthermore, we explored the association between social cognition measures, clinical symptoms and executive functions. Using a logistic regression analysis, we explored whether the involvement of more basic skills in emotional processing predicted performance on empathy tasks. The results showed that both patient groups exhibited deficits in social cognition tasks with greater context sensitivity and involvement of real-life scenarios. These deficits were more severe in schizophrenic than in bipolar patients. Patients did not differ from controls in tasks involving explicit knowledge. Moreover, schizophrenic patients’ depression levels were negatively correlated with performance on empathy tasks.

CONCLUSIONS/SIGNIFICANCE: Overall performance on emotion recognition predicted performance on intentionality attribution during the more ambiguous situations of the empathy task. These results suggest that social cognition deficits could be related to a general impairment in the capacity to implicitly integrate contextual cues. Important implications for the assessment and treatment of individuals with schizophrenia and bipolar disorders, as well as for neurocognitive models of these pathologies are discussed.

It is commonly assumed thatearly emotional signals provide relevant informationfor social cognition tasks. The goal of this study was to test the association between (a) cortical markers of face emotional processing and (b) social-cognitive measures,and also to build a model which can predictthis association (a & b) in healthy volunteers as well as in different groups of psychiatric patients. Thus, we investigated the early cortical processing of emotional stimuli (N170, using a face and word valence task) and their relationship with the social-cognitive profiles (SCPs, indexed by measures of theory of mind, fluid intelligence, speed processing, and executive functions). Group comparisons and individual differences were assessed among schizophrenia (SCZ) patients and their relatives, individuals with attention deficit hyperactivity disorder (ADHD), individuals with euthymic bipolar disorder (BD) and healthy participants (educational level, handedness, age and gendermatched). Our results provide evidence of emotional N170 impairments in the affected groups (SCZ and relatives, ADHD and BD) as well as subtle group differences. Importantly, cortical processing of emotional stimuli predicted the social cognition profile (SCP), as evidenced by a structural equation model (SEM) analysis. This is the first study to report anassociation model of brain markers of emotional processing and SCP.

Empathy is a highly flexible and adaptive process that allows for the interplay of prosocial behavior in many different social contexts. Empathy appears to be a very situated cognitive process, embedded with specific contextual cues that trigger different automatic and controlled responses. In this review, we summarize relevant evidence regarding social context modulation of empathy for pain. Several contextual factors, such as stimulus reality and personal experience, affectively link with other factors, emotional cues, threat information, group membership, and attitudes toward others to influence the affective, sensorimotor, and cognitive processing of empathy. Thus, we propose that the frontoinsular-temporal network, the so-called social context network model (SCNM), is recruited during the contextual processing of empathy. This network would (1) update the contextual cues and use them to construct fast predictions (frontal regions), (2) coordinate the internal (body) and external milieus (insula), and (3) consolidate the context-target associative learning of empathic processes (temporal sites). Furthermore, we propose these context-dependent effects of empathy in the framework of the frontoinsular-temporal network and examine the behavioral and neural evidence of three neuropsychiatric conditions (Asperger syndrome, schizophrenia, and the behavioral variant of frontotemporal dementia), which simultaneously present with empathy and contextual integration impairments. We suggest potential advantages of a situated approach to empathy in the assessment of these neuropsychiatric disorders, as well as their relationship with the SCNM.

La cognición social es dependiente de la información sutil e implícita presente en el contexto durante interacciones sociales. Presentamos y describimos un modelo anatomofuncional, denominado SCNM (del inglés Social Context Network Model), que pretende explicar cómo se procesa el contexto en situaciones sociales. Además, muestra cómo diferentes alteraciones de sus redes subyacen a los déficits en cognición social de pacientes con demencia frontotemporal, lesiones fronto-insulares, enfermedades del neurodesarrollo y otros cuadros neuropsiquiátricos. Se presentan estudios precursores basados en el SCNM y se los contrapone al enfoque descontextualizado de abordajes clásicos en cognición social. El SCNM es un modelo teórico que provee un conjunto de hipótesis que permiten examinar y comprender mejor los procesos subyacentes a los déficits en cognición social. A nivel clínico, propone el desarrollo de herramientas más ecológicas que las tradicionales que permitirían una mejor detección y caracterización de distintas enfermedades neurológicas y psiquiátricas, como así también la implementación de ambientes en rehabilitación que imiten mejor las situaciones de la vida cotidiana