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171.
The contextual modulation of conditioned taste aversions by the physical environment and time of day is similar 下载免费PDF全文
Morón I Manrique T Molero A Ballesteros MA Gallo M Fenton A 《Learning & memory (Cold Spring Harbor, N.Y.)》2002,9(5):218-223
In a pair of experiments, we have compared the ability of changes of place (Exp. 1) and changes of time of day (Exp. 2) to separately modulate learned saline-aversion memory phenomena in rats. Neither a spatial nor a temporal change disrupted latent inhibition using the present behavioral procedure. However, pre-exposure to the taste increased the contextual control of the learned aversion expression. The aversion reappeared in the place or at the time of conditioning after extinction in a different context. The results indicate that environmental and temporal contexts can independently, but similarly modulate taste aversion learning. 相似文献
172.
The positive effect of postlearning sleep on memory consolidation as well as the relationship between sleep-related memory processes and the hippocampal formation are increasingly clarified topics in neurobiology. However, the possibility of a stable relationship between waking mnemonic performance and sleep-dependent hippocampal electric activity is unexplored. Here we report a correlative analysis between sleep-dependent parahippocampal-hippocampal (pHip-Hip) electric activity recorded by foramen ovale (FO) electrodes and different types of memory performances in epileptic patients. Psychological testing was performed days or weeks before electrophysiological recordings. The relative spectral power of the slow activity (below 1.25 Hz) during deep non-REM (NREM) sleep at the right pHip-Hip region correlated positively with the visual memory performance according to Rey-Osterrieth Complex Figure Test (ROCFT). Along the posterior-anterior direction of the hippocampal formation a linear increasing of correlations was observed. The relative power of the activity below 1.25 Hz at the left pHip-Hip during phasic REM sleep correlated positively with verbal learning performance and mnemonic retention values according to ROCFT. It is concluded that the pHip-Hip structures' capacity of producing high amplitude and synchronized slow (< 1 Hz) oscillation during deep NREM sleep is related to the functional power of these structures. We hypothesize that the asymmetric (side-specific) propagation of ponto-geniculo-occipital (PGO) activity to the pHip-Hip region is related to the memory correlates of phasic REM sleep. 相似文献
173.
Twenty-four adults (24 to 53 years old) with Attention-Deficit/Hyperactivity Disorder (ADHD), Combined Type, were studied in a double-blind, placebo-controlled, crossover study of Pycnogenol and methylphenidate. Pycnogenol is an antioxidant derived from the bark of the French maritime pine tree. Methylphenidate is a standard pharmaceutical intervention for ADHD. Anecdotal reports suggest that Pycnogenol improves concentration in adults with ADHD without adverse side effects. Participants received Pycnogenol, methylphenidate, and placebo, each for three weeks, in a randomized and counterbalanced order. Although ADHD symptoms improved during treatment, neither methylphenidate nor Pycnogenol outperformed the placebo control, as measured by self-report rating scales, rating scales completed by the individual's significant other, and a computerized continuous performance test. The conservative dosage levels and relatively brief length of treatment may have contributed to the absence of significant differences among treatment conditions. Implications for future research are noted. 相似文献
174.
This chart review examined the effects of effort on neuropsychological assessment and test performance patterns among genuine and exaggerating patients, with and without neurological findings, as aids to diagnosing symptom exaggeration. The sample consisted of 561 consecutive patients involved in compensation claims. With a flexible neuropsychological test (NPT) battery, the claims were assessed over 2 days. The sample included 303 patients evaluated for traumatic brain injury, 55 patients with neurological disease, and 203 patients assessed for other conditions (eg, depression or chronic pain). An average of 38 ability measures per patient were used to generate an overall NPT domain score. Composite scores were also computed for symptom validity tests, self-report measures of psychiatric symptoms, and memory complaint inventory. Seven NPT cognitive subdomain scores were multiply regressed onto the symptom validity test composite, accounting for 45% of its total variance. Patients were also assigned to Genuine or Exaggerator groups based on symptom validity test performance. The NPT for Exaggerating patients averaged 1.43 standard deviations below that of Genuine patients, suggesting that NPT scores for most Exaggerating patients are underestimates of their true ability. Factor analysis results differed between these groups. As a result, clinicians might avoid falsely identifying genuine patients as exaggerating by incorporating their self-reports of psychiatric symptoms and memory complaints into the diagnostic process. 相似文献
175.
RAP: a new framework for visual categorization 总被引:1,自引:0,他引:1
Cognitive science might almost be defined as several disciplines communicating their different perspectives on the mind, the common object of study. However, domain-specific concepts and techniques can prevent, rather than foster, a communication of viewpoints. In this article, we develop a new framework for visual categorization in which the interaction between Represented (R) information and Available (A) information determine the Potent (P) information (symbolically, R ? A approximately P). We argue and illustrate that this framework helps to establish a common language to articulate issues common to low-, mid-, and high-level vision. More importantly, we present new techniques with which to visualize the so-far elusive constructs of representation and potent information. 相似文献
176.
On the self-protective nature of inconsistency-negativity management: using the person memory paradigm to examine self-referent memory 总被引:6,自引:0,他引:6
How do individuals remember feedback that is inconsistent or negative? According to the inconsistency-negativity resolution model, individuals are motivated to reduce uncertainty and resolve inconsistency even when threat to self is potential. They more deeply process and better remember negative self- than other-referent information. According to the inconsistency-negativity neglect model, individuals are motivated to protect the self against threat. They engage in more shallow processing and remember less negative self- than other-referent information. Participants read and recalled either self- or other-referent mixed-valence information. The neglect model was supported in personality and minimal feedback settings. A chronometric exploration of processing mechanisms and the ruling out of a retrieval interference account clarified aspects of the model. Individuals are hypersensitive to threat potential: They will protect the self against even hypothetical threat. 相似文献
177.
This work is divided in two papers (Part I and Part II). In Part I, we study a class of polymodal logics (herein called the class of "Rare-logics") for which the set of terms indexing the modal operators are hierarchized in two levels: the set of Boolean terms and the set of terms built upon the set of Boolean terms. By investigating different algebraic properties satisfied by the models of the Rare-logics, reductions for decidability are established by faithfully translating the Rare-logics into more standard modal logics. The main idea of the translation consists in eliminating the Boolean terms by taking advantage of the components construction and in using various properties of the classes of semilattices involved in the semantics. The novelty of our approach allows us to prove new decidability results (presented in Part II), in particular for information logics derived from rough set theory and we open new perspectives to define proof systems for such logics (presented also in Part II). 相似文献
178.
Data illustrating the biological week and chronomes are presented in recognition of extensive work of G. Hildebrandt. 相似文献
179.
Bernhard Plé 《Journal of Happiness Studies》2000,1(4):423-445
Auguste Comte (1798–1857) is the founder of a French school of thought that became famous for its encyclopaedic account of the sciences as well as for its exposition of what was designed as a way out of a state of intellectual and moral crisis. This essay demonstrates that there is a linkage between the diagnosis of crisis and the pursuit of happiness in Comte's foundation of positivism. It begins by distinguishing Comte's notion of positivism from that of a value-free science. In analysing Comte's peculiar usage of the term happiness, the essay shows that happiness is understood as the result of the convergence (consensus) of three components: a scientific conception of the world, the feelings of love and veneration, and a wisely ordered activity. The essay then demonstrates that the first of these components is of primary importance inasmuch as it is to frame a new horizon within which man is expected to return to a healthy state of mind, to reshape both his hopes and activities, and to discover his own participation in a supreme order acting through the laws of nature as well as through those of the civilization in which he lives. Conveying this new horizon to citizens of a lasting Republic is the sacred mission of sociology. The essay concludes by pointing out that Comte's conception of happiness can be assessed as unifying some main qualities of life as they are classified in Ruut Veenhoven's fourfold matrix. 相似文献
180.
The aim of this research is to model and simulate the loss of visual resolution as a function of retinal eccentricity in the perception of natural scenes. The model of visual resolution is based on a space-variant low-pass filter, having a variable convolution kernel according to retinal eccentricity. The parameters of the model are computed from psychophysical measures of visual acuity as a function of retinal eccentricity. The implementation of the model allowed us to generate images of scenes with nonhomogeneous space-variant resolution, simulating the filtering executed by the eye. These scenes are used to test and optimise the model by means of experiments in static vision (through tachistoscopic presentations) and in dynamic vision where the resolution of the scene is computed, in real-time, as a function of the location of gaze. 相似文献