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161.
Nieuwenhuis S Ridderinkhof KR Talsma D Coles MG Holroyd CB Kok A van der Molen MW 《Cognitive, affective & behavioral neuroscience》2002,2(1):19-36
When participants commit errors or receive feedback signaling that they have made an error, a negative brain potential is elicited. According to Holroyd and Coles’s (in press) neurocomputational model of error processing, this error-related negativity (ERN) is elicited when the brain first detects that the consequences of an action are worse than expected. To study age-related changes in error processing, we obtained performance and ERN measures of younger and high-functioning older adults. Experiment 1 demonstrated reduced ERN amplitudes in older adults in the context of otherwise intact brain potentials. This result could not be attributed to uncertainty about the required response in older adults. Experiment 2 revealed impaired performance and reduced response- and feedback-related ERNs of older adults in a probabilistic learning task. These age changes could be simulated by manipulation of a single parameter of the neurocomputational model, this manipulation corresponding to weakened phasic activity of the mesencephalic dopamine system. 相似文献
162.
Manbir?SodhiEmail author Bryan?Reimer Ignacio?Llamazares 《Behavior research methods》2002,34(4):529-538
With the increasing use of in-vehicle devices in cars, an understanding of the safety implications of secondary tasks has become crucial. It is now possible to study the effects of many in-vehicle devices and tasks on driving by using head-mounted eye-tracking devices (HEDs) to collect eye positions and pupil diameters, which have been considered indicators of attentional focus. The collection of eye-position and pupil-diameter data of automobile drivers under on-road conditions and while completing various secondary tasks is described in this paper. Drivers were asked to drive on a preselected two-lane road for a total distance of 22 miles while gaze data were recorded using a HED. Longer off-road fixation durations were observed in radio-tuning and rearview mirror checking tasks, but not in the odometer checking task. In addition, the standard deviations of fixation displacements during a cognitive task involving the computation of a date for a meeting were shorter than those observed during normal driving. 相似文献
163.
Laura?Barca Cristina?BuraniEmail author Lisa?S.?Arduino 《Behavior research methods》2002,34(3):424-434
The present study describes normative measures for 626 Italian simple nouns. The database (LEXVAR. XLS) is freely available for down-loading on the Web site http://wwwistc.ip.rm.cnr.it/material/ database/. For each of the 626 nouns, values for the following variables are reported: age of acquisition, familiarity, imageability, concreteness, adult written frequency, child written frequency, adult spoken frequency, number of orthographic neighbors, mean bigram frequency, length in syllables, and length in letters. A classification of lexical stress and of the type of word-initial phoneme is also provided. The intercorrelations among the variables, a factor analysis, and the effects of variables and of the extracted factors on word naming are reported. Naming latencies were affected primarily by a factor including word length and neighborhood size and by a word frequency factor. Neither a semantic factor including imageability, concreteness, and age of acquisition nor a factor defined by mean bigram frequency had significant effects on pronunciation times. These results hold for a language with shallow orthography, like Italian, for which lexical nonsemantic properties have been shown to affect reading aloud. These norms are useful in a variety of research areas involving the manipulation and control of stimulus attributes. 相似文献
164.
Shepherd I. Franz was an important figure in psychology of the last century, and historians of psychology have given recognition
to much of his work. However, his experimental work with animals and his pioneer investigations in experimental and clinical
neuropsychology have been largely ignored. This article reviews his conceptual, assessment, and treatment contributions, including
(1) his pioneering work on the use of learned behavior as a baseline for the study of cerebral ablations, (2) his interest
in brain plasticity, (3) his development of comprehensive psychological assessment methods, and (4) his work on the rehabilitation
of neurological patients with techniques derived from his animal experiments. His work predated much of what is now part of
the conceptual substance of the experimental and clinical neurosciences. 相似文献
165.
The frequency of theta activity may be important for hippocampal function. Anxiolytic drugs reduce theta frequency and have behavioral effects that are similar to those of hippocampal lesions. The effect of the anxiolytic benzodiazepine chlordiazepoxide (CDP) on theta frequency is partially mediated by the medial supramammillary nucleus (mSuM), part of an ascending theta-activating system. Rats were trained on the hippocampal-sensitive fixed-interval 60-sec schedule (FI60). CDP (5 mg/kg i.p.) released responding suppressed by nonreward, seen as increased leverpressing, and reduced theta frequency concurrently. Microinfusion of CDP (20 μg in 0.5 μl saline) into mSuM had as large effects on both frequency and behavior. Other nuclei mediate the benzodiazepine reduction of theta frequency in the open field and the water maze. But the mSuM appears to be the major, if not sole, nucleus controlling theta frequency and, so, hippocampal-mediated behavioral inhibition in the FI60 lever task. 相似文献
166.
167.
Kevin?D.?BeckEmail author Francis?X.?Brennan Richard?J.?Servatius 《Integrative psychological & behavioral science》2002,37(2):128-139
In this study we assessed habituation and sensitization of the acoustic startle response (ASR) to discern whether intense,
inescapable stress affects nonassociative learning differently in male and female rats. Rats were inescapably stressed 2 hours
per day over 3 consecutive days. ASR magnitudes were measured at several times post-stress (1, 4, 8, and 15 days after cessation).
Females generally showed greater ASR magnitudes (compared to males), but both sexes exhibited short and long-term habituation
across the testing days. ASR magnitudes were only affected by stress in male subjects. The effect in males was an increase
in short-term sensitization of the ASR on post-stress day-4. The results suggest that stressed males and females react differently
to ASR testing, in that stress males appear to develop an exaggerated ASR response over repeated test sessions due to short-term
sensitization. The source of the short-term sensitization is discussed with regards to possible stress-induced enhanced contextual
learning during ASR testing on post-stress day-1. 相似文献
168.
Daniel Tr?hler 《Studies in Philosophy and Education》2000,19(1):219-221
Biography
Notes on Contributors 相似文献169.
We examined whether the functionality of spatial relations affects the construction and memory of information in situation models. A functional relationship involves the interaction of entities that is implied by either typical use or contextual demands. Previous research has shown that spatial relations are less likely to be encoded during comprehension unless there is extensive prior knowledge, explicit instructions to attend to spatial information, or a clear emphasis on spatial information. If the construction of a situation model is guided by a need to understand the functional structure of a situation, then functional spatial relations should be more likely to be encoded. The results of our study showed that sentences with functional spatial relations were read faster and remembered better in both recall and recognition tests than sentences with nonfunctional spatial relations. 相似文献
170.
Scientific misconduct includes the fabrication, falsification, and plagiarism (FFP) of concepts, data or ideas; some institutions
in the United States have expanded this concept to include “other serious deviations (OSD) from accepted research practice.”
It is the absence of this OSD clause that distinguishes scientific misconduct policies of the past from the “research misconduct”
policies that should be the basis of future federal policy in this area. This paper introduces a standard for judging whether
an action should be considered research misconduct as distinguished from scientific misconduct: by this standard, research
misconduct must involve activities unique to the practice of science and must have the potential to negatively affect the
scientific record. Although the number of cases of scientific misconduct is uncertain (only the NIH and the NSF keep formal
records), the costs are high in terms of the integrity of the scientific record, diversions from research to investigate allegations,
ruined careers of those eventually exonerated, and erosion of public confidence in science. Existing scientific misconduct
policies vary from institution to institution and from government agency to government agency; some have highly developed
guidelines that include OSD, others have no guidelines at all. One result has been that the federal False Claims Act has been
used to pursue allegations of scientific misconduct. As a consequence, such allegations have been adjudicated in federal courts,
rather than judged by scientific peers. The federal government is now establishing a first-ever research misconduct policy
that would apply to all research funded by the federal government regardless of which agency funded the research or whether
the research was carried out in a government, industrial or university laboratory. Physical scientists, who up to now have
only infrequently been the subject of scientific misconduct allegations, must nonetheless become active in the debate over
research misconduct policies and how they are implemented since they will now be explicitly covered by this new federal wide
policy.
Disclaimer: The authors are grateful for the support for conduct of this research provided by the United States Department of Energy
(DOE). The views expressed in this paper are solely those of the authors and were formed and expressed without reference to
positions taken by DOE or the Pacific Northwest National Laboratory (PNNL). The views of the authors are not intended either
to reflect or imply positions of DOE or PNNL. 相似文献