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81.
Animals recognize a taste cue as aversive when it has been associated with post-ingestive malaise; this associative learning is known as conditioned taste aversion (CTA). When an animal consumes a new taste and no negative consequences follow, it becomes recognized as a safe signal, leading to an increase in its consumption in subsequent presentations (attenuation of neophobia, AN). It has been shown that the nucleus accumbens (NAcc) has an important role in taste learning. To elucidate the involvement of N-methyl-D-aspartate (NMDA) and muscarinic receptors in the NAcc during safe and aversive taste memory formation, we administrated bilateral infusions of DL-2-amino-5-phosphonopentanoic acid (APV) or scopolamine in the NAcc shell or core respectively. Our results showed that pre-training injections of APV in the NAcc core and shell disrupted aversive but not safe taste memory formation, whereas pre-training injections of scopolamine in the NAcc shell, but not core, disrupted both CTA and AN. These results suggest that muscarinic receptors seem to be necessary for processing taste stimuli for either safe or aversive taste memory, whereas NMDA receptors are only involved in the aversive taste memory trace formation.  相似文献   
82.
Working memory (WM) plays an important role in children’s learning and is linked to later academic and occupational success. Understanding the early development of WM can provide critical clues regarding the underlying structure of executive functions and how they change over the life span. The main objectives of the present study were to (1) investigate age differences in the development of three components of WM (retrieval, substitution, transformation) on a novel preschool WM measure and (2) explore whether findings are consistent with the hierarchical model of WM development by examining perseverative and non-perseverative WM errors. Perseverative errors were hypothesized to be more strongly associated with problems substituting and transforming a representation held in mind, whereas non-perseverative errors were hypothesized to be associated with problems maintaining a representation in mind. Participants were 64 children ranging in age from 3.0 to 5.6 years. The results provide evidence for the sensitivity of the WM task to age differences from 3 to 5 years and support for the hierarchical model of WM development.  相似文献   
83.
This longitudinal study was conducted among 102 women with non-metastasic breast cancer to identify the time evolution and prevalence of distress at specific times through diagnosis and treatment of disease: preliminary diagnosis, surgery, definitive diagnosis and chemotherapy. Additionally, the study aimed to examine the role of demographic, medical and psychosocial factors on distress. The results indicated that prevalence of distress was higher at initial diagnosis (25%) than the following time points (approximately 17%). The differences inter-individuals in the levels of distress were observed over the four assessments. No relation between distress and demographic and medical factors was found. However, psychosocial aspects were significant risk factors. Patterns of emotional suppression and specific coping responses like helplessness/hopelessness, anxious preoccupation, cognitive avoidance and fatalism were positively related to distress, whereas fighting spirit and perceived social support showed a protective role. Moreover, helplessness/hopelessness and anxious preoccupation jointly predicted 75% of cases and 98% non-cases of distress. Finally, a mediational model between emotional suppression and distress through helplessness/hopelessness was tested. Results support the necessity of routine distress screening all through the illness. Implications of data for psychosocial interventions with breast cancer patients are highlighted.  相似文献   
84.

Purpose  

This study investigated whether meeting electronically first using computer-mediated communication (CMC) before meeting face-to-face (FTF) increases the inclusion of a female group member in a predominantly male project team.  相似文献   
85.
In this paper we present a new framework of idealization in biology. We characterize idealizations as a network of counterfactual and hypothetical conditionals that can exhibit different ??degrees of contingency??. We use this idea to say that, in departing more or less from the actual world, idealizations can serve numerous epistemic, methodological or heuristic purposes within scientific research. We defend that, in part, this structure explains why idealizations, despite being deformations of reality, are so successful in scientific practice. For illustrative purposes, we provide an example from population genetics, the Wright-Fisher Model.  相似文献   
86.
In this article we report on listener categorization of meaningful environmental sounds. A starting point for this study was the phenomenological taxonomy proposed by Gaver (1993b). In the first experimental study, 15 participants classified 60 environmental sounds and indicated the properties shared by the sounds in each class. In a second experimental study, 30 participants classified and described 56 sounds exclusively made by solid objects. The participants were required to concentrate on the actions causing the sounds independent of the sound source. The classifications were analyzed with a specific hierarchical cluster technique that accounted for possible cross-classifications, and the verbalizations were submitted to statistical lexical analyses. The results of the first study highlighted 4 main categories of sounds: solids, liquids, gases, and machines. The results of the second study indicated a distinction between discrete interactions (e.g., impacts) and continuous interactions (e.g., tearing) and suggested that actions and objects were not independent organizational principles. We propose a general structure of environmental sound categorization based on the sounds' temporal patterning, which has practical implications for the automatic classification of environmental sounds.  相似文献   
87.
This study broaches in a novel way the analysis of cognitive impairment characteristic of the early stages of Alzheimer's Disease (AD). Specifically, we attempt to determine the acoustic speech parameters that are sensitive to the onset of the disease, and their association with the language deficit characteristic of AD. Speech analysis was carried out on 21 elderly patients with AD using Praat software, which analyzes the acoustic components of speech. The data obtained were subjected to stepwise regression, using the overall scores obtained in the test as the criterion variable, and the scores on the frequency, amplitude and periodicity variables as predictors of performance. We found that the percentage of voiceless segments explains a significant portion of the variance in the overall scores obtained in the neuropsychological test. This component seems to be related mainly to the patient's ability in phonological fluency. This finding could permit the creation of a diagnostic test for AD through analysis of the acoustic speech parameters at very low cost in terms of both time and resources.  相似文献   
88.
The aim of this study was to analyse the screening utility of the Social Anxiety Screening Scale (SASS/EDAS) in a sample of 227 adolescents with social anxiety disorder and 156 Without it (14-17 years). Results showed that the EDAS subscales (Avoidance, Distress and Interference) scores were reliable in terms of internal consistency (alpha > .80). All the subscales discriminated between adolescents with and without the disorder. They also showed a positive and significant correlation with other empirically validated measures of social anxiety. The three subscales indicated relevant sensitivity (69.16-84.14%), specificity (63.46-66.03%) and areas under the curve (.74-.81%). Binary logistic regression analyses indicated the adequate predictive utility of EDAS subscales, with the Distress subscale as the best diagnostic predictor. The data provide empirical evidence of the usefulness of EDAS as a screener for adolescent social anxiety disorder in terms of reliability, convergent and discriminant validity, diagnostic accuracy and clinical usefulness.  相似文献   
89.
90.
Brain event-related potentials are a useful tool for investigating visual processing and action planning. This technique requires extremely accurate synchronization of stimulus delivery with recordings. The precision of the onset time of visual stimulus delivery is a major challenge when attempting to use real, three-dimensional objects as stimuli. Here, we present an innovative device, the “box for interaction with objects” (BIO), that is designed to synchronize the presentation of objects with electroencephalographic (EEG) recordings. To reach the required resolution of stimulus-onset timing, the BIO system features an interface with reflective glass and light-emitting diodes (LEDs). When the LEDs inside the BIO are turned on, the object inside becomes visible, and a synchronizing pulse is sent to the recording systems. The BIO was tested in a motivational study that focused on visual and motor event-related potentials. EEG signals were recorded during the presentation of an emotion-laden object that could be grasped and brought close to the participant’s chest. BIO successfully synchronized the appearance of a three-dimensional object with EEG recordings, which would allow for an analysis of visual and motor event-related potentials in the same experiment. The BIO device, through a high-quality psychophysiological approach, offers a new perspective for the study of the motivational factors that drive actions toward relevant stimuli.  相似文献   
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