1,810 research outputs found
The simulation of action disorganisation in complex activities of daily living
Action selection in everyday goal-directed tasks of moderate complexity is known to be subject to breakdown following extensive frontal brain injury. A model of action selection in such tasks is presented and used to explore three hypotheses concerning the origins of action disorganisation: that it is a consequence of reduced top-down excitation within a hierarchical action schema network coupled with increased bottom-up triggering of schemas from environmental sources, that it is a more general disturbance of schema activation modelled by excessive noise in the schema network, and that it results from a general disturbance of the triggering of schemas by object representations. Results suggest that the action disorganisation syndrome is best accounted for by a general disturbance to schema activation, while altering the balance between top-down and bottom-up activation provides an account of a related disorder - utilisation behaviour. It is further suggested that ideational apraxia (which may result from lesions to left temporoparietal areas and which has similar behavioural consequences to action disorganisation syndrome on tasks of moderate complexity) is a consequence of a generalised disturbance of the triggering of schemas by object representations. Several predictions regarding differences between action disorganisation syndrome and ideational apraxia that follow from this interpretation are detailed
How brains make decisions
This chapter, dedicated to the memory of Mino Freund, summarizes the Quantum
Decision Theory (QDT) that we have developed in a series of publications since
2008. We formulate a general mathematical scheme of how decisions are taken,
using the point of view of psychological and cognitive sciences, without
touching physiological aspects. The basic principles of how intelligence acts
are discussed. The human brain processes involved in decisions are argued to be
principally different from straightforward computer operations. The difference
lies in the conscious-subconscious duality of the decision making process and
the role of emotions that compete with utility optimization. The most general
approach for characterizing the process of decision making, taking into account
the conscious-subconscious duality, uses the framework of functional analysis
in Hilbert spaces, similarly to that used in the quantum theory of
measurements. This does not imply that the brain is a quantum system, but just
allows for the simplest and most general extension of classical decision
theory. The resulting theory of quantum decision making, based on the rules of
quantum measurements, solves all paradoxes of classical decision making,
allowing for quantitative predictions that are in excellent agreement with
experiments. Finally, we provide a novel application by comparing the
predictions of QDT with experiments on the prisoner dilemma game. The developed
theory can serve as a guide for creating artificial intelligence acting by
quantum rules.Comment: Latex file, 20 pages, 3 figure
Dynamic Assessment of Narrative Competence
In Developmental Education, language plays an essential role as a tool for communication (and thinking). Learning to produce coherent messages (“narratives”) with both cultural and personal value in the context of meaningful socio-cultural practices is considered as an important goal of Developmental Education. Narratives are essential for human action as they function as a tool for giving meaning to reality. Therefore, close observation and assessment of children’s narratives is essential in the context of Developmental Education. Over the past years we have developed a Dynamic Assessment (DA) instrument for assessing children’s narrative competence. This instrument combines two common approaches to DA, namely standardised interventionist DA and interactionist DA. With the help of this instrument, teachers are able to gain insight into children’s actual narrative competence as well as their developmental potential and their receptivity to certain forms of assistance to reach this potential. Our experience up to now shows that it is possible to assess children’s narrative competence in a valid and reliable manner
Alternative Mechanisms for Tn5 Transposition
Bacterial transposons are known to move to new genomic sites using either a replicative or a conservative mechanism. The behavior of transposon Tn5 is anomalous. In vitro studies indicate that it uses a conservative mechanism while in vivo results point to a replicative mechanism. To explain this anomaly, a model is presented in which the two mechanisms are not independent—as widely believed—but could represent alternate outcomes of a common transpositional pathway
The Buffer Gas Beam: An Intense, Cold, and Slow Source for Atoms and Molecules
Beams of atoms and molecules are stalwart tools for spectroscopy and studies
of collisional processes. The supersonic expansion technique can create cold
beams of many species of atoms and molecules. However, the resulting beam is
typically moving at a speed of 300-600 m/s in the lab frame, and for a large
class of species has insufficient flux (i.e. brightness) for important
applications. In contrast, buffer gas beams can be a superior method in many
cases, producing cold and relatively slow molecules in the lab frame with high
brightness and great versatility. There are basic differences between
supersonic and buffer gas cooled beams regarding particular technological
advantages and constraints. At present, it is clear that not all of the
possible variations on the buffer gas method have been studied. In this review,
we will present a survey of the current state of the art in buffer gas beams,
and explore some of the possible future directions that these new methods might
take
Computational Cancer Biology: An Evolutionary Perspective
ISSN:1553-734XISSN:1553-735
Acquisition vs. Memorization Trade-Offs Are Modulated by Walking Distance and Pattern Complexity in a Large-Scale Copying Paradigm
In a “block-copying paradigm”, subjects were required to copy a configuration of colored blocks from a model area to a distant work area, using additional blocks provided at an equally distant resource area. Experimental conditions varied between the inter-area separation (walking distance) and the complexity of the block patterns to be copied. Two major behavioral strategies were identified: in the memory-intensive strategy, subjects memorize large parts of the pattern and rebuild them without intermediate visits at the model area. In the acquisition-intensive strategy, subjects memorize one block at a time and return to the model after having placed this block. Results show that the frequency of the memory-intensive strategy is increased for larger inter-area separations (larger walking distances) and for simpler block patterns. This strategy-shift can be interpreted as the result of an optimization process or trade-off, minimizing combined, condition-dependent costs of the two strategies. Combined costs correlate with overall response time. We present evidence that for the memory-intensive strategy, costs correlate with model visit duration, while for the acquisition-intensive strategy, costs correlate with inter-area transition (i.e., walking) times
Vygotsky in English: What Still Needs to Be Done
At present readers of English have still limited access to Vygotsky’s writings. Existing translations are marred by mistakes and outright falsifications. Analyses of Vygotsky’s work tend to downplay the collaborative and experimental nature of his research. Several suggestions are made to improve this situation. New translations are certainly needed and new analyses should pay attention to the contextual nature of Vygotsky’s thinking and research practice
Prematurity, executive functions and quality of parental care: a systematic review
Este artigo de revisĂŁo visa contextualizar o desenvolvimento das funções executivas (FE) em crianças prematuras, com especial atenção para o efeito dos cuidados parentais. As principais bases eletrĂ´nicas foram utilizadas para essa revisĂŁo: 31 estudos originais, duas meta-análises, uma meta-sĂntese e dois artigos de revisĂŁo foram identificados. Concluiu-se que as crianças prematuras tĂŞm maior risco de disfunção executiva global, sendo a qualidade dos cuidados parentais fundamentais para a modulação das FE, nomeadamente no que concerne Ă s variáveis socioemocionais da interação, como a sensibilidadematerna. Salientam-se ainda as principais limitações dos estudos analisados e apontam-se recomendações para futura investigação sobre os efeitos dos cuidados parentais no desenvolvimento de FE em crianças prematuras.This review article aims to contextualize the development of executive functions (EF) in preterm children with special attention to the effects of parental care. The main electronic databases were used for this review: 31 original studies, two meta-analyses, one meta-synthesis and two systematic reviews were identified. The results showed that preterm infants are at risk for global executive dysfunction,and that the quality of parenting impacts the development of EF, mainly in terms of interactive socio-emotional variables, like maternal sensitivity.Finally, the main limitations of the analyzed studies are pointed out, and recommendations of future research about the effects of parental care in the development of EF in preterm children are offered.(undefined)info:eu-repo/semantics/publishedVersio
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