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241.
The present study examined the relationship between the predictability of words within a sentence and the availability of
parafoveal word length information, on when and where the eyes move in reading. Predictability influenced first-pass reading
times when parafoveal word length preview information was correct, but not when it was incorrect. Similarly, for saccades
launched from near the target word (wordn), predictability influenced the probability with which it was skipped only when the word length preview was correct. By contrast,
for saccades launched farther away from wordn, predictability influenced word skipping regardless of the parafoveal word length preview. Taken together, the data suggest
that parafoveal word length preview and predictability can act as a joint constraint on the decision of when and where to
move the eyes. 相似文献
242.
Fos protein expression in olfactory-related brain areas after learning and after reactivation of a slowly acquired olfactory discrimination task in the rat
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Roullet F Liénard F Datiche F Cattarelli M 《Learning & memory (Cold Spring Harbor, N.Y.)》2005,12(3):307-317
Fos protein immunodetection was used to investigate the neuronal activation elicited in some olfactory-related areas after either learning of an olfactory discrimination task or its reactivation 10 d later. Trained rats (T) progressively acquired the association between one odor of a pair and water-reward in a four-arm maze. Two groups of pseudotrained rats were used: PO rats were not water restricted and were submitted to the olfactory stimuli in the maze without any reinforcement, whereas PW rats were water-deprived and systematically received water in the maze without any odorous stimulation. When the discrimination task was well mastered, a significantly lower Fos immunoreactivity was observed in T rats compared to PW and PO rats in most of the analyzed brain areas, which could reflect the post-acquisition consolidation process. Following memory reactivation, differences in Fos immunoreactivity between trained and some pseudotrained rats were found in the anterior part of piriform cortex, CA3, and orbitofrontal cortex. We also observed that Fos labeling was significantly higher in trained rats after memory reactivation than after acquisition of the olfactory task in most of the brain areas examined. Our results support the assumption of a differential involvement of neuronal networks after either learning or reactivation of an olfactory discrimination task. 相似文献
243.
Angiotensin II (ANGII) has an evolutionary preserved role in determining adaptative responses to water-shortages. In addition, it has been shown to modulate diverse phases of memory. Still, it is not clear whether ANGII improves or spoils memory. We demonstrated that endogenous angiotensins enhance consolidation of a long-term associative memory in the crab Chasmagnathus and that water shortage improves memory consolidation through brain ANGII actions. Here, we show that weakly trained crabs, when water-deprived, exhibit enhanced retrieval. Subsequently, memory retention is indistinguishable from that of strongly trained crabs. ANGII, but not angiotensin IV, is a necessary and sufficient condition for such enhancing effect. We conclude that ANGII released due to water shortage leads to enhanced memory retrieval. Thus, it seems that ANGII has an evolutionary preserved role as a multifunction coordinator that enables an adaptative response to water-shortage. The facilitation of memory consolidation and retrieval would be among those coordinated functions. 相似文献
244.
Cammarota M Bevilaqua LR Rossato JI Ramirez M Medina JH Izquierdo I 《Neurobiology of learning and memory》2005,84(1):25-32
Both the acquisition and the extinction of memories leave short- and long-term mnemonic traces. Here, we show that in male Wistar rats, the short-term memory for a step-down inhibitory avoidance task (IA) is resistant to extinction, and that its expression does not influence retrieval or extinction of long-term memory. It has been known for some time that short- and long-term inhibitory avoidance memory involve separate and parallel processes. Here we show that, instead, short-term extinction of IA long-term memory is the first step towards its long-term extinction, and that this link requires functional NMDA receptors and protein synthesis in the CA1 region of the dorsal hippocampus at the time of the first CS-no US presentation. 相似文献
245.
A number of measures have been used in epidemiological studies of children's exposure to community violence, yet the quality
of these instruments is not uniformly good. This paper undertakes a systematic review of the most commonly used (or most promising)
self-report or interview-administered instruments, with regard to their conceptual bases and psychometric properties. Based
on the review, recommendations are made for working with the current state of the science in order to move the field forward.
A key recommendation is for sounder conceptualization of work in the field and greater transparency in the reporting of research,
in order to facilitate the comparability of studies. 相似文献
246.
The aim of this study is to analyze how the length of time a patient spends in an Intensive Care Unit (ICU) affects close relatives, with regard to specific clinical variables of personality, family relationships and fear of death. The study group consisted of 57 relatives of seriously ill patients admitted to the ICU of "Virgen del Rocío" Rehabilitation and Trauma Hospital (Seville, Spain). The instruments applied were: a psychosocial questionnaire, clinical analysis questionnaire, family environment scale and fear of death scale. The relatives of patients admitted to ICU obtained higher scores in hypochondria, suicidal depression, agitation, anxious depression, guilt-resentment, paranoia, psychasthenia, psychological maladjustment and self-expression, and less in fear of their own death, as when compared to interviews with the same relatives 4 years later. The length of time a patient spent in the ICU influenced relatives in some clinical variables of personality, family relationships and fear of death 相似文献
247.
Flores Sarazúa E Borda Más M Pérez San Gregorio MA 《The Spanish journal of psychology》2005,8(1):45-55
The purpose of this survey is to detect common personality features in people infected with AIDS who have a case history of drug addiction and who live in a situation of social exclusion. The sample comprised 105 male participants from the Autonomous Community of Andalusia, divided into 4 groups: (a) 30 men with AIDS, having an intravenous drug addiction case history and who live in a condition of social exclusion; (b) 30 men with IVDA case history, also living in a situation of social exclusion; (c) 15 men in a social exclusion condition; and (d) 30 men in a condition of social adaptation. The evaluation instruments were an author-designed semi-structured interview and the Multiaxial Clinical Inventory (MCMI-II; Millon, 1987). Although some differences were found, the results indicate that there is no specific personality profile in the "social exclusion" population. People in a condition of social exclusion (AIDS, drug addicts, and poor people) may obtain similar scores in the variables studied, but there is no clear specific personality profile in the excluded population, although there may be certain situations in which the segregated groups present similar behaviors. Furthermore, these behaviors do not always correspond to personality features but are adaptive responses to a harsh and complex reality. 相似文献
248.
In the context of a medium-term study designed to integrate the simulation of different types and processes of learning-such as classical, operant, and some cognitive types--one must start with other more elementary ones that are facilitators of the more complex types and processes. Of special interest is habituation, owing to the filtering out of irrelevant stimuli, which means that the simulated agent does not have to respond to them. This paper presents two difference functions constructed to computationally simulate the characteristics that define habituation. The behavior of these functions is described, as are differences arising from stimulus intensity and interstimulus intervals. Results are compared with existing empirical data. 相似文献
249.
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
250.
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