Fodor's and Pylyshyn's stand on systematicity in thought and language has been debated and criticized. Van Gelder and Niklasson, among others, have argued that Fodor and Pylyshyn offer no precise definition of systematicity. However, our concern here is with a learning based formulation of that concept. In particular, Hadley has proposed that a network exhibits strong semantic systematicity when, as a result of training, it can assign appropriate meaning representations to novel sentences (both simple and embedded) which contain words in (...) syntactic positions they did not occupy during training. The experience of researchers indicates that strong systematicity in any form is difficult to achieve in connectionist systems.Herein we describe a network which displays strong semantic systematicity in response to Hebbian, connectionist training. During training, two-thirds of all nouns are presented only in a single syntactic position (either as grammatical subject or object). Yet, during testing, the network correctly interprets thousands of sentences containing those nouns in novel positions. In addition, the network generalizes to novel levels of embedding. Successful training requires a, corpus of about 1000 sentences, and network training is quite rapid. The architecture and learning algorithms are purely connectionist, but classical insights are discernible in one respect, viz, that complex semantic representations spatially contain their semantic constituents. However, in other important respects, the architecture is distinctly non-classical. (shrink)

It has been proposed that the implicate order can be given mathematical expression in terms of an algebra and that this algebra is similar to that used in quantum theory. In this paper we bring out in a simple way those aspects of the algebraic formulation of quantum theory that are most relevant to the implicate order. By using the properties of the standard ket introduced by Dirac we describe in detail how the Heisenberg algebra can be generalized to produce (...) an algebraic structure in which it is possible to describe space translations in a way that is analogous to the description of rotations in a Clifford algebra. This approach opens up the possibility of going beyond the limits of the present quantum formalism and we discuss briefly some of the new implications. (shrink)

We review some of the essential novel ideas introduced by Bohm through the implicate order and indicate how they can be given mathematical expression in terms of an algebra. We also show how some of the features that are needed in the implicate order were anticipated in the work of Grassmann, Hamilton, and Clifford. By developing these ideas further we are able to show how the spinor itself, when viewed as a geometric object within a geometric algebra, can be given (...) a meaning which transcends the notion of the usual metric geometry in the sense that it must be regarded as an element of a broader and more general pregeometry. (shrink)

An eminent psychologist and a gerontologist explain how to cope with the problems of aging and how to get the most out of one's later years.

Three experiments investigated the relationship between subjective experience and attentional lapses during sustained attention. These experiments employed two measures of subjective experience to examine how differences in awareness correspond to variations in both task performance and psycho-physiological measures . This series of experiments examine these phenomena during the Sustained Attention to Response Task . The results suggest we can dissociate between two components of subjective experience during sustained attention: task unrelated thought which corresponds to an absent minded disengagement from the (...) task and a pre-occupation with one's task performance that seems to be best conceptualised as a strategic attempt to deploy attentional resources in response to a perception of environmental demands which exceed ones ability to perform the task. The implications of these findings for our understanding of how awareness is maintained on task relevant material during periods of sustained attention are discussed. (shrink)

Antonio Argandoña, Norbert Bilbeny, Victòria Camps, Miquel Calsina, Àngel Castiñeira, Cristian Palazzi, Ferran Requejo, Raimon Ribera, Begoña Román, Ferran Sàez, Miquel Seguró, Francesc Torralba, Josep Maria Vallès, Rosamund Thomas Ramon Llull Journal of Applied Ethics 2012 3(3):9-16.

Yoga is believed to have beneficial effects on cognition, attenuation of emotional intensity and stress reduction. Previous studies were mainly performed on eastern experienced practitioners or unhealthy subjects undergoing concomitant conventional therapies. Further investigation is needed on the effects of yoga per se, as well as its possible preventive benefits on healthy subjects. We investigated the effects of yoga on memory and psychophysiological parameters related to stress, comparing yoga practice and conventional physical exercises in healthy men . Memory tests, salivary (...) cortisol levels and stress, anxiety, and depression inventories were assessed before and after 6 months of practice. Yoga practitioners showed improvement of the memory performance, as well as improvements in psychophysiological parameters. The present results suggest that regular yoga practice can improve aspects of cognition and quality of life for healthy individuals. An indirect influence of emotional state on cognitive improvement promoted by yoga practice can be proposed. (shrink)

The study of reciprocal altruism, or the exchange of goods and services between individuals, requires attention to both evolutionary explanations and proximate mechanisms. Evolutionary explanations have been debated at length, but far less is known about the proximate mechanisms of reciprocity. Our own research has focused on the immediate causes and contingencies underlying services such as food sharing, grooming, and cooperation in brown capuchin monkeys and chimpanzees. Employing both observational and experimental techniques, we have come to distinguish three types of (...) reciprocity. Symmetry-based reciprocity is cognitively the least complex form, based on symmetries inherent in dyadic relationships (e.g., mutual association, kinship). Attitudinal reciprocity, which is more cognitively complex, is based on the mirroring of social attitudes between partners and is exhibited by both capuchin monkeys and chimpanzees. Finally, calculated reciprocity, the most cognitively advanced form, is based on mental scorekeeping and is found only in humans and possibly chimpanzees. (shrink)

We formulate and analyze the dynamics of an influenza pandemic model with vaccination and treatment using two preventive scenarios: increase and decrease in vaccine uptake. Due to the seasonality of the influenza pandemic, the dynamics is studied in a finite time interval. We focus primarily on controlling the disease with a possible minimal cost and side effects using control theory which is therefore applied via the Pontryagin’s maximum principle, and it is observed that full treatment effort should be given while (...) increasing vaccination at the onset of the outbreak. Next, sensitivity analysis and simulations (using the fourth order Runge-Kutta scheme) are carried out in order to determine the relative importance of different factors responsible for disease transmission and prevalence. The most sensitive parameter of the various reproductive numbers apart from the death rate is the inflow rate, while the proportion of new recruits and the vaccine efficacy are the most sensitive parameters for the endemic equilibrium point. (shrink)

We investigate computational properties of propositional logics for dynamical systems. First, we consider logics for dynamic topological systems (W.f), fi, where W is a topological space and f a homeomorphism on W. The logics come with ‘modal’ operators interpreted by the topological closure and interior, and temporal operators interpreted along the orbits {w, f(w), f2 (w), ˙˙˙} of points w ε W. We show that for various classes of topological spaces the resulting logics are not recursively enumerable (and so not (...) recursively axiomatisable). This gives a ‘negative’ solution to a conjecture of Kremer and Mints. Second, we consider logics for dynamical systems (W, f), where W is a metric space and f and isometric function. The operators for topological interior/closure are replaced by distance operators of the form ‘everywhere/somewhere in the ball of radius a, ‘for a ε Q +. In contrast to the topological case, the resulting logic turns out to be decidable, but not in time bounded by any elementary function. (shrink)

Current thinking on the development of molecular microbial characterisation techniques in public health focuses mainly on operational issues that need to be resolved before incorporation into daily practice can take place. Notwithstanding the importance of these operational challenges, it is also essential to formulate conditions under which such microbial characterisation methods can be used from an ethical perspective. The potential ability of molecular techniques to show relational patterns between individuals with more certainty brings a new sense of urgency to already (...) difficult ethical issues associated with privacy, consent and a moral obligation to avoid spreading a disease. It is therefore important that professionals reflect on the ethical implications of using these techniques in outbreak management, in order to be able to formulate the conditions under which they may be applied in public health practice. (shrink)

Through discourse with international groups of physicians, we conducted a cross-cultural analysis of the types of ethical dilemmas physicians face. Qualitative analysis was used to categorise the dilemmas into seven themes, which we compared among the physicians by country of practice. These themes were a-theoretically-driven and grounded heavily within the text. We then subjected the dilemmas to an analysis of moral intensity, which represents an important theoretical perspective of ethical decision making. These constructs represent salient determinants of ethical behaviour and (...) our cross-cultural sample afforded us the opportunity to consider both the pragmatic aspects of culture, as they are perceived by physicians, as well as the theory-driven concept of moral intensity. By examining both culture and moral intensity, we hope to better elucidate the complexities of ethical decision-making determinants among physicians in their daily practice. Doing so may potentially have practical implications for ethics training of medical students and foreign physicians. (shrink)

BackgroundIn the Canadian Alliance for Healthy Hearts and Minds (CAHHM) cohort, participants underwent magnetic resonance imaging (MRI) of the brain, heart, and abdomen, that generated incidental findings (IFs). The approach to managing these unexpected results remain a complex issue. Our objectives were to describe the CAHHM policy for the management of IFs, to understand the impact of disclosing IFs to healthy research participants, and to reflect on the ethical obligations of researchers in future MRI studies.MethodsBetween 2013 and 2019, 8252 participants (...) (mean age 58 ± 9 years, 54% women) were recruited with a follow-up questionnaire administered to 909 participants (40% response rate) at 1-year. The CAHHM policy followed a restricted approach, whereby routine feedback on IFs was not provided. Only IFs of severe structural abnormalities were reported.ResultsSevere structural abnormalities occurred in 8.3% (95% confidence interval 7.7–8.9%) of participants, with the highest proportions found in the brain (4.2%) and abdomen (3.1%). The majority of participants (97%) informed of an IF reported no change in quality of life, with 3% of participants reporting that the knowledge of an IF negatively impacted their quality of life. Furthermore, 50% reported increased stress in learning about an IF, and in 95%, the discovery of an IF did not adversely impact his/her life insurance policy. Most participants (90%) would enrol in the study again and perceived the MRI scan to be beneficial, regardless of whether they were informed of IFs. While the implications of a restricted approach to IF management was perceived to be mostly positive, a degree of diagnostic misconception was present amongst participants, indicating the importance of a more thorough consent process to support participant autonomy.ConclusionThe management of IFs from research MRI scans remain a challenging issue, as participants may experience stress and a reduced quality of life when IFs are disclosed. The restricted approach to IF management in CAHHM demonstrated a fair fulfillment of the overarching ethical principles of respect for autonomy, concern for wellbeing, and justice. The approach outlined in the CAHHM policy may serve as a framework for future research studies.Clinical trial registrationhttps://clinicaltrials.gov/ct2/show/nct02220582. (shrink)