Causal reasoning and the diagnostic process

Background: Causal reasoning as a way to make a diagnosis seems convincing. Modern medicine depends on the search for causes of disease and it seems fair to assert that such knowledge is employed in diagnosis. Causal reasoning as it has been presented neglects to some extent the conception of multifactorial disease causes. Goal: The purpose of this paper is to analyze aspects of causation relevant for discussing causal reasoning in a diagnostic context. Procedures: The analysis will discuss different conceptions of causal reasoning in medical diagnosis, discriminating primarily between narrow causal diagnosis and more thorough causal explanation. The theory of causes as non-redundant factors in effective causal complexes is used as an analytical background. Causal explanations are performed according to different causal models. Such models of diagnosis are assumptions concerning structure and mechanisms, which cannot be directly or immediately observed. Conceptions and results of causal search strategies differ, according to the focus of the searcher. Causal reasoning is also seen in diagnosis in a more extensive meaning: the pin-pointing of factors responsible for the condition of the patient at any time during the course of disease. Conclusion: Causal reasoning and diagnosis go well in hand, especially if both concepts are widened. The theory of causes as non-redundant components in effective causal complexes, modulated by what is referred to as the stop problem and causal fields, is valuable for explaining the many aspects of causal reasoning in medical diagnosis.     

Agreement and movement: a syntactic analysis of attraction

This paper links experimental psycholinguistics and theoretical syntax in the study of subject-verb agreement. Three experiments of elicited spoken production making use of specific characteristics of Italian and French are presented. They manipulate and examine its impact on the occurrence of 'attraction' errors (i.e. incorrect agreement with a word that is not the subject of the sentence). Experiment 1 (in Italian) shows that subject modifiers do not trigger attraction errors in free inverted VS (Verb Subject) structures, although attraction was found in VS interrogatives in English (Vigliocco, G., & Nicol, J. (1998). Separating hierarchical relations and word order in language production. Is proximity concord syntactic or linear? Cognition, 13-29) In Experiment 2 (in French), we report stronger attraction with preverbal clitic object pronouns than with subject modifiers. Experiment 3 (in French) shows that displaced direct objects in the cleft construction trigger attraction effects, in spite of the fact that the object does not intervene between the subject and the verb in the surface word order (OSV). Moreover, attraction is stronger in structures with subject-verb inversion (...). These observations are shown to be naturally interpretable through the tools of formal syntax, as elaborated within the Principles and Parameters/Minimalist tradition. Three important constructs are discussed: (1) the hierarchical representation of the sentence during syntactic construction, and the role of intermediate positions by which words transit when they move; (2) the role of specific hierarchical (c-command) but also linear (precedence) relations; and (3) the possibility that agreement involves two functionally distinct components. A gradient of computational complexity in agreement is presented which relates empirical evidence to these theoretical constructs.     

Causality in medicine: Towards a theory and terminology

One of the cornerstones of modern medicine is the search for what causes diseases to develop. A conception of multifactorial disease causes has emerged over the years. Theories of disease causation, however, have not quite been developed in accordance with this view. It is the purpose of this paper to provide a fundamental explication of aspects of causation relevant for discussing causes of disease. The first part of the analysis will discuss discrimination between singular and general causality. Singular causality, as in the specific patient, is a relation between a concrete sequence of causally linked events. General causation, e.g. as in disease etiology, means various categories of causal relations between event types. The paper introduces the concept of a reference case serving as a source for causal inference, reaching beyond the concept of general causality. The second part of the analysis provides exemplification of a theory of causation suitable for discussing singular causation. The chain of events that induce a disease state can be identified as effective causal complexes, each complex composed of nonredundant components, which separately contribute to the effect of the complex, without the individual component being necessary or sufficient in itself to produce the effect. In the third part of the analysis the theory is elaborated further. Causes, defined as nonredundant components, can furthermore be differentiated according to their avoidability, according to theories about human error or by the potential of eradication. Multifactorial models of disease creates a need for systematic approaches to causal factors. The paper proposes a taxonomical terminology that serves this purpose.     

Aspects of grammatical development in young French children with SLI

This paper presents an exploratory study of the spontaneous production of 11 French children clinically diagnosed as specific language impaired (SLI). In a cross‐sectional study of the children under and over 5 years of age, we investigate the production of finite and non‐finite verbal forms, of sentences with overt and null subjects, and of pronominal clitics. A comparison between younger and older children with SLI highlights developmental patterns which parallel normal syntactic development in important respects, though at a slower pace. An area of difficulty which clearly persists for the older group involves the domain of pronominal complement clitics.     

Nanoporous gold obtained from a metallic glass precursor used as substrate for surface-enhanced Raman scattering

Nanoporous gold (NPG) has been synthesized by electrochemical de-alloying a new precursor, amorphous Au₃₀Cu₃₈Ag₇Pd₅Si₂₀ (at.%), starting from melt-spun ribbons. Ligaments ranging from 75 to 210 nm depending on the de-alloying time were obtained. Analytical and electrochemical evidence showed the ligaments contain residual Cu, Ag and Pd. Surface-enhanced Raman scattering from the NPG was investigated using pyridine and 4,4′-bi-pyridine as probe molecules. It was found that the activity is at maximum when the ribbon is fully de-alloyed although the ligaments then have a larger size. The enhancement is attributed to the small size of crystals in the ligaments, to their morphology and to trapped atoms.     

In judo,Randori (free fight) and Kata (highly ritualized fight) differentially change plasma cortisol,testosterone, and interleukin levels in male participants

Two forms of competitive encounters namely Randori (free fight) and Kata (highly ritualized fight) were studied in 22 professional male judo fighters. The dyadic, symmetrical (in terms of body weight and fighting ability) encounters were videotaped to assess relationships between agonistic behavior and individual variations in plasma levels of testosterone (T), cortisol (C) and interleukins (IL‐6 and IL‐1β) measured before and after the competition. Unremarkably, winners showed longer attack but devoted less time to defensive behaviors when compared to losers. T increased only during Randori but the individual pre‐ and post‐competition T levels recorded in such fights were strongly correlated with the corresponding measures in the Kata for the same individuals. Interestingly, the pre‐ and post‐Randori competition T levels were higher in losers than in winners and T variations positively correlated with the frequencies of attacks and with the duration of defensive postures. The T response shows individual variation and seems to reflect evaluation of the likelihood of winning or losing. Both Randori and Kata induced a marked C increase, although the pre‐ and post‐Randori hormonal titers were higher than those found for the Kata. IL‐6 significantly increased between the pre‐ and the post‐Randori competition, but no such changes occurred during the Kata. No correlations were found between individual pre‐ and post‐competition C and IL‐6 and IL‐1β levels in either Randori or Kata. This suggests that C and cytokine release are unrelated to emotional or cognitive perception of the possible outcome of fighting but are a consequence of general motor activity. Martial arts appear to provide good human models to understand: (a) the relationships between conflict, hormones and the immune system and (b) the relationships between mood and physiological responses to competitive aggression. Aggr. Behav. 32:1–9, 2006. © 2006 Wiley‐Liss, Inc.     

Medical prognosis — Some fundamentals

Background: The concept of prognosis as a prediction concerning the probable outcome of an attack of disease shows some severe contextual drawbacks in the everyday clinical sense. It is often used to describe possible outcomes of the disease in general, or the progression of a disease course, not the expected course in a particular case. Goal: To render more discriminating uses of the term prognosis, in order to provide the prognosticating physician with a valid tool, comparable to the theoretical basis of diagnostic and therapeutic actions. Procedures: Analysis and discussion of etymology, definition and practical usage. Conclusion: Prognosis is not to be considered soothsaying, but forecasting on qualified grounds. Prognostic statements are announcements containing prognostic information. Prognostic factors are pieces of information associated with a specific outcome of disease, which can be utilized in the formulation of the prognosis. Prognostic estimates involve subjective probability and can be formulated by using frequencies along with (clinical) experience. A prognosis is a prediction of a particular future stage of disease, considering a single case — the prognosis is neither part of the patient, nor part of the disease.     

The indirect effect of cognitive reserve on the relationship between age and cognition in pathological ageing: A cross-sectional retrospective study in an unselected and consecutively enrolled sample

Cognitive reserve (CR) allows individuals to maintain cognitive functionality even in the presence of pathologies. The compensation hypothesis suggests that CR plays an indirect role between age and cognitive decline, contrasting the negative effect of ageing on cognition. We test this hypothesis in an unselected and consecutively enrolled sample of memory clinic attendees (n = 134) who completed the CR Index questionnaire and three neuropsychological tests assessing global cognition (MMSE, FAB, CDT). Participants were divided into two groups based on standard diagnostic criteria (DSM-5): those who were cognitively impaired (n = 92) and those who were preserved (n = 42). A principal component analysis was used to extract a composite measure of global cognitive functioning from the three neuropsychological tests, and mediation analysis was used to examine the relationship between CR, age and global cognitive functioning in the two groups. Results revealed that: (i) age had a significant direct negative effect on the global cognitive score in both groups; (ii) the three socio-behavioural proxies of CR together suppress the direct negative relationship between age and global cognitive score in cognitively impaired patients but not in cognitively preserved participants. This study confirms the association between CR, age and cognition and allows us to validate its role in a population with cognitive impairment and extend findings to a low-to-middle educated population. These results hold important implications for public health and wellness promotion, emphasising the beneficial role of maintaining healthy and active physical, cognitive and social lifestyles.