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121.
Empirical examinations of the hypothesis of dedifferentiation of cognitive abilities in old and very old age (a) do not account for possible retest effects, which consequently may yield biased estimates of age effects, and (b) focus on time-independent relations (e.g., number of latent constructs, correlations between latent or measured variables). The authors applied a structural equation model with statistical control for retest effects to investigate the dynamic relations between a marker of perceptual speed (cross out) and a marker of verbal fluency (category-fruits). Longitudinal data are from 5 waves of the Swiss Interdisciplinary Longitudinal Study on the Oldest Old (N = 377, baseline age range = 79.5- 84.5 years). The authors found that, independently of retest effects, performance on the cross-out task affected changes in performance on the category task while the opposite did not hold true. This analytical technique could be applied to various markers of broad fluid-mechanic and broad crystallized-pragmatic components of cognition. 相似文献
122.
Koch I 《Psychonomic bulletin & review》2005,12(1):107-112
Many studies of task switching have found that a prolonged preparation time reduces switch costs. An alternative manipulation
of task preparation is based on sequential task predictability, rather than preparation time. In Experiments 1 and 2 of the
present study, participants performed explicitly instructed task sequences (i.e., AABB) and were then transferred to a random
sequence. The observed benefit of predictability-based task preparation was not switch specific. In Experiment 3, the participants
changed from random to predictable tasks. The observed predictability benefit again was not switch specific. The data thus
suggest that task switching does not necessarily require a switch-specific reconfiguration process. Rather, task-specific
control processes may be needed in both task switches and repetitions. 相似文献
123.
Twenty-four detoxified opiate addicts were randomized to an experimental group and a control group to evaluate efficacy of a group cue-exposure treatment to reduce or extinguish classically conditioned responses to drug-related stimuli. Assessment included psychophysiological responses (skin temperature, skin conductance level--SCL--, and heart rate) to a videotape and subjective measures (subjective craving, positive and negative affect) before and after the videotape. The experimental group received a group cue-exposure program to drug-related stimuli that comprised twelve treatment sessions administered three times weekly. The treatment program significantly reduced conditioned responses to drug-related stimuli, as measured by SCL and positive affect. 相似文献
124.
Over the last years several European patents were opposed for protecting technology violating the morality requirement under
Article 53(a) EPC. Attempts have been made by the Appeal Boards of the European Patent Office (EPO), as well as by amendments
introduced into the Implementing Regulations of the European Patent Convention (EPC), to address this sensitive patentability
requirement more precisely. The most recent hot topic coming up in this context is the patentability of stem cells. It is
to be expected that this discussion will still go on in the field of biotechnological inventions for the next several years.
An earlier version of this paper was presented at an international conference, “The Ethics of Intellectual Property Rights
and Patents,” held in Warsaw, Poland on 23–24 April, 2004. 相似文献
125.
Nanotechnology — A new field of ethical inquiry? 总被引:2,自引:0,他引:2
Grunwald A 《Science and engineering ethics》2005,11(2):187-201
Parallel to the public discussion on the benefits and risks of nanotechnology, a debate on the ethics of nanotechnology has
begun. It has been postulated that a new “nano-ethics” is necessary. In this debate, the — positive as well as negative —
visionary and speculative innovations which are brought into connection with nanotechnology stand in the foreground. In this
contribution, an attempt is made to discover new ethical aspects of nanotechnology in a more systematic manner than has been
the case. It turns out that there are hardly any completely new ethical aspects raised by nanotechnology. It is much rather
primarily a case of gradual shifts of emphasis and of relevance in questions which, in principle, are already known and which
give reason for ethical discussions on nanotechnology. In a certain manner, structurally novel ethical aspects arise through
the important role played by visions in the public discourse. New questions are also posed by the fact that previously separate
lines of ethical reflection converge in the field of nanotechnology. The proposal of an independent “nano-ethics”, however,
seems exaggerated. 相似文献
126.
127.
Weak phantasmata have a decisive and specifically transcendental function in our everyday perception. This paper provides several different arguments for this claim based on evidence from both empirical psychology and phenomenology.I would like to express my gratitude to Bill McKenna for his help with the English text and his critical remarks. This paper was presented in the Cork Roundtable for Philosophy in March 2003, at University College, Cork, and I would like to thank Julia Jansen, Tony O’Connor and the other participants for their constructive critique. 相似文献
128.
The aims of the present review are to apply a recent risk factor approach (H. C. Kraemer et al., 1997) to putative risk factors for eating disorders, to order these along a timeline, and to deduce general taxonomic questions. Putative risk factors were classified according to risk factor type, outcome (anorexia nervosa, bulimia nervosa, binge-eating disorder, full vs. partial syndromes), and additional factor characteristics (specificity, potency, need for replication). Few of the putative risk factors were reported to precede the onset of the disorder. Many factors were general risk factors; only few differentiated between the 3 eating disorder syndromes. Common risk factors from longitudinal and cross-sectional studies were gender, ethnicity, early childhood eating and gastrointestinal problems, elevated weight and shape concerns, negative self-evaluation, sexual abuse and other adverse experiences, and general psychiatric morbidity. Suggestions are made for the conceptualization of future risk factor studies. 相似文献
129.
130.
de Vries PH 《Psychological research》2004,69(1-2):41-66
The binding problem requires a solution at the level of individual neurons, but no definite mechanism has yet be given. Therefore, the neuronal level is as yet inadequate for modeling cognitive processes in which binding plays a crucial role. Moreover, the neuronal level involves too many details that are unlikely to be essential for understanding cognition. A general model of cognitive brain functioning is described in which cognitive tasks are represented in a network of cell assemblies. In the network, binding is functionally defined in a way that is compatible with the neuronal level. A computer simulation of the model clarifies how the binding of location and identity of a set of simultaneously presented letters takes place and how questions about the location and identity of the letters are answered. From the simulation of the task three predictions on the logistics of neural processes are derived: 1. When the cell assembly representing a letter participates in more than one temporary excitation loop, it will reach its critical threshold faster. At the behavioral level this means that as the number of identical letters in the display increases, responses will be faster. 2. In order to answer questions about the location and identity of presented letters cell assemblies representing the target location and the target identity have to become bound to their appropriate values. As a consequence the facilitatory effect of identical letters will be stronger if they involve the target location or the target identity than when identical non-targets are involved. 3. Negative identifications are more dependent on the presentation time of the letters than positive identifications because the excitation loops involved take more time to reach the critical threshold. Therefore, the facilitatory effect of identical letters is stronger when the external activation is relatively strong, i.e., when presentation time of the letters is sufficiently long. The reaction times obtained in three behavioral experiments support these hypotheses. Effects of binding can therefore be predicted on the basis of the general logistics of neural processes, without assumptions about a specific binding mechanism at the neuronal level. 相似文献