Is a picture worth a thousand words? Evidence from concept definitions by patients with semantic dementia

Nine patients with semantic dementia (the temporal lobe variant of frontotemporal dementia) were asked to define concrete concepts either from presentation of a picture of the object or from its spoken name. As expected, the patients with the most severe semantic impairment produced the least detailed definitions, and the quality of the definitions overall was significantly related to concept familiarity. Further analyses of the definitions were designed to assess two key theoretical aspects of semantic organization. (i) Do objects and their corresponding names activate conceptual information in two neuroanatomically separable (modality-specific) semantic systems? If so, then-apart from any expected commonality in performance attributable to factors such as concept familiarity-one would not predict striking item-specific similarities in a patient's picture- and word-elicited definitions. (ii) Do sensory/perceptual features and more associative/functional attributes of conceptual knowledge form two neuroanatomically separable subsystems? If so, then one would predict significant dissociations in the prominence of these two types of information in the patients' definitions. The results lead us to favor a model of the semantic system that is divided by attribute type but not by modality.     

The Relation between Formal and Informal Logic

The issue of the relationship between formal and informal logic depends strongly on how one understands these two designations. While there is very little disagreement about the nature of formal logic, the same is not true regarding informal logic, which is understood in various (often incompatible) ways by various thinkers. After reviewing some of the more prominent conceptions of informal logic, I will present my own, defend it and then show how informal logic, so understood, is complementary to formal logic.     

Schleiermacher and Spirit Christology: Unexplored Horizons of The Christian Faith

One of the more recent efforts at christological construction has focused on Spirit christology, issuing in sometimes opposing constructions. At first sight, considering Schleiermacher's synthetic approach to the doctrine of the Trinity, one would suspect the irrelevance of his christology for these present efforts. However, an analysis of the convergence between christology and pneumatology in the Glaubenslehre could contribute significantly to this debate. By interpreting the God-consciousness of Jesus as the presence of the Spirit in him and correlating this with the communication of this consciousness as the work of Christ in regeneration and sanctification we achieve an identity between Christ as Spirit-bearer and Spirit-sender (viz. the Redeemer understood according to his 'peculiar activity' and 'exclusive dignity'). By lending a stronger pneumatological bearing to Schleiermacher's theological discourse (picking up the suggestion of Karl Barth) Schleiermacher helps illuminate some of the issues that have arisen in debate over Spirit christology.     

Unpicking the semantic impairment in Alzheimer's disease: qualitative changes with disease severity

Despite a vast literature examining semantic impairment in Alzheimer's disease (AD), consensus regarding the nature of the deficit remains elusive. We re-considered this issue in the context of a framework that assumes semantic cognition can break down in two ways: (1) core semantic representations can degrade or (2) cognitive control mechanisms can become impaired. We hypothesised and confirmed that the nature of semantic impairment in AD changes with disease severity. Patients at mild or severe stages of the disorder exhibited impairment across various semantic tasks but the nature of those deficits differed qualitatively for the two groups. Commensurate with early dysfunction of the cognitive control, temporoparietal-frontal-cingulate network, characteristics of deregulated semantic cognition were exhibited by the mild AD cases. In contrast, the severe AD group reproduced features of additional degradation of core semantic representations. These results suggest that spread of pathology into lateral anterior temporal lobes in later stage AD produces degradation of semantic representations, exacerbating the already deregulated system. Moreover, the dual nature of severe patients' impairment was highlighted by disproportionately poor performance on tasks placing high demand on both conceptual knowledge and control processes--e.g., category fluency.     

How do people judge risks: Availability heuristic, affect heuristic, or both?

How does the public reckon which risks to be concerned about? The availability heuristic and the affect heuristic are key accounts of how laypeople judge risks. Yet, these two accounts have never been systematically tested against each other, nor have their predictive powers been examined across different measures of the public's risk perception. In two studies, we gauged risk perception in student samples by employing three measures (frequency, value of a statistical life, and perceived risk) and by using a homogeneous (cancer) and a classic set of heterogeneous causes of death. Based on these judgments of risk, we tested precise models of the availability heuristic and the affect heuristic and different definitions of availability and affect. Overall, availability-by-recall, a heuristic that exploits people's direct experience of occurrences of risks in their social network, conformed to people's responses best. We also found direct experience to carry a high degree of ecological validity (and one that clearly surpasses that of affective information). However, the relative impact of affective information (as compared to availability) proved more pronounced in value-of-a-statistical-life and perceived-risk judgments than in risk-frequency judgments. Encounters with risks in the media, in contrast, played a negligible role in people's judgments. Going beyond the assumption of exclusive reliance on either availability or affect, we also found evidence for mechanisms that combine both, either sequentially or in a composite fashion. We conclude with a discussion of policy implications of our results, including how to foster people's risk calibration and the success of education campaigns. (PsycINFO Database Record (c) 2012 APA, all rights reserved).     

Biological Indeterminacy

Reductionist explanations in biology generally assume that biological mechanisms are highly deterministic and basically similar between individuals. A contrasting view has emerged recently that takes into account the degeneracy of biological processes??the ability to arrive at a given endpoint by a variety of available paths, even within the same individual. This perspective casts significant doubt on the prospects for the ability to predict behavior accurately based on brain imaging or genotyping, and on the ability of neuroscience to stipulate ethics.     

The role of contextual associations in producing the partial reinforcement acquisition deficit

Three conditioned suppression experiments with rats as subjects assessed the contributions of the conditioned stimulus (CS)-context and context-unconditioned stimulus (US) associations to the degraded stimulus control by the CS that is observed following partial reinforcement relative to continuous reinforcement training. In Experiment 1, posttraining associative deflation (i.e., extinction) of the training context after partial reinforcement restored responding to a level comparable to the one produced by continuous reinforcement. In Experiment 2, posttraining associative inflation of the context (achieved by administering unsignaled outcome presentations in the context) enhanced the detrimental effect of partial reinforcement. Experiment 3 found that the training context must be an effective competitor to produce the partial reinforcement acquisition deficit. When the context was down-modulated, the target regained behavioral control thereby demonstrating higher-order retrospective revaluation. The results are discussed in terms of retrospective revaluation, and are used to contrast the predictions of a performance-focused model with those of an acquisition-focused model.     

Development of parenting self‐efficacy in mothers of infants with high negative emotionality

Maternal parenting self‐efficacy (PSE) is a potential target for infant mental health interventions because it is associated with a number of positive outcomes for children and mothers. Understanding the development of maternal PSE under conditions of increased parenting stress, such as parenting an infant who is easily distressed and difficult to soothe, will contribute to providing more effective interventions. This study examines the development of maternal PSE in mothers of infants with high negative emotionality (NE). The Neonatal Behavioral Assessment Scale (NBAS; T. Brazelton, 1973 ) was administered twice to 111 infants to select a sample of irritable (n = 24) and nonirritable (n = 29) infants for a prospective study comparing the development of PSE in mothers of infants differing in neonatal NE. Consistent with our hypotheses and previous research, at 8 weeks' postpartum, mothers of irritable infants have significantly lower domain‐specific PSE than do mothers of nonirritable infants. Contrary to our predictions, mothers of irritable infants exhibit a significant increase in domain‐specific and domain‐general PSE from 8 to 16 weeks' postpartum. The implications of these results for infant mental health screening, infant mental health interventions, and research on self‐efficacy theory are discussed.     

Language and tool making are similar cognitive processes

Design features for language and stone toolmaking (not tool use) involve similar if not homologous cognitive processes. Both are arbitrary transformations of internal "intrinsic" symbolization, whereas non-human tool using is mostly an iconic transformation. The major discontinuity between humans and non-humans (chimpanzees) is language. The presence of stone tools made to standardized patterns suggests communicative and social control skills that involved language.