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61.
Depending on the brain networks involved, aging is not accompanied by a general decrease in learning and memory capabilities. We demonstrated previously that learning and retrieval of taste potentiated odor aversion (TPOA) is preserved, and even slightly improved, in senescent rats showing some memory deficiencies in cognitive tasks (Dardou, Datiche, & Cattarelli, 2008). TPOA is a particular behavior in which the simultaneous presentation of odor and taste cues followed by a delayed visceral illness leads to a robust aversion towards both conditioned stimuli, which permits diet selection and animal survival. The present experiment was performed in order to investigate the stability or the evolution of the brain network underlying TPOA retrieval during aging. By using immunocytochemical detection of Fos and Egr1 proteins we mapped the cerebral activation induced by TPOA retrieval elicited by the odor presentation in the young, the adult and the senescent rats. The pattern of brain activation changed and the number of activated areas decreased with age. Nevertheless, the piriform cortex and the basolateral amygdala nucleus were always activated and seemed essential for TPOA retrieval. The hippocampus and the neocortical areas could have different implications in TPOA memory in relation to age. The patterns of expression of Fos and Egr1 were different, suggesting their differential involvement in TPOA retrieval. Data are discussed according to the possible roles of the brain areas studied and a model of schematic brain network subtending TPOA retrieval induced by the odor cue is proposed.  相似文献   
62.
A proof of magnetic compass learning by pigeons under laboratory conditions has been attempted for decades, but all experiments have failed so far. The aim of the present study was to test whether pigeons can learn magnetic compass directions in an operant chamber if magnetic cues are presented as true spatial cues. Experimental sessions were carried out in the local geomagnetic field and in magnetic fields with matched total intensity and inclination, but different directions generated with Helmholtz-coils. Birds demonstrated successful learning with a performance level comparable to that in learning studies with magnetic anomalies. In addition, we compared the data from magnetic learning in the laboratory with performance from homing experiments in the field. The birds that were more successful in the learning experiment had vanishing bearings farther away from the home direction than the group mean at unfamiliar, but not at familiar sites. This might suggest that better learners explore unknown locations in a different way. Our findings represent the first evidence for operant magnetic compass learning in pigeons and also provide a link between behavioural data from the field and the laboratory.  相似文献   
63.
In the 2-4-6 rule discovery task, reasoners seek to discover a rule that governs the arrangement of three numbers (or triple). The to-be-discovered rule is “ascending numbers”. Upon being given the triple 2-4-6 as an initial example, however, reasoners tend to formulate algebraically specific hypotheses. Traditionally, this task is conducted primarily from an internal representation of the triples and candidate hypotheses. More recently, substantial representational effects have been demonstrated wherein an external representation of the dimensions of the problem space facilitated successful rule discovery. In the two experiments reported here, an interactive graphical representation was created by concurrently plotting each triple produced by the participants. In Experiment 1, participants who performed the task with this external representation were more likely to discover the rule than were a group of control participants. Experiment 2 replicated the effect but also assessed participants' hypotheses for each triple generated. Results indicated that a graphical representation of the triples fostered the development of hypotheses that were less constrained by the implied algebraic specificity of the initial triple.  相似文献   
64.
The authors investigated the coordination of periodic right-hand tapping with single stimulus-evoked discrete lefthand taps to check for task interactions and a possible relationship between phase resetting (see tapping literature; e.g., J. Yamanishi, M. Kawato, & R. Suzuki, 1979) and phase entrainment (see tremor literature; e.g., R. J. Elble, C. Higgins, & L. Hughes, 1994). The experimental paradigm employs a dual-task condition as used by K. Yoshino, K. Takagi, T. Nomura, S. Sato, and M. Tonoike (2002), and it includes normal tapping and isometric tapping with the authors recording finger positions and ground contact forces. Four different types of coordination schemes were observed in tapping behavior: marginal tapping interaction (MTI), periodic tap retardation (PTR), periodic tap hastening (PTH), and discrete tap entrainment (DTE); MTI and PTR correspond to the phase-resetting effect for the coordination of periodic tapping with single discrete taps. The novel aspect of the study described in this article includes the impact of the periodic tapping on the discrete tap timing and the hastening of the periodic tapping due to the discrete tap behaviors resulting in a synchronized execution of the two concurrent tapping tasks. All participants showed a dominant tapping behavior, but they all used the other nondominant forms of the four reported coordination schemes in some trials too, which reflects possible constraints of the sensorimotor system in handling two competing tasks.  相似文献   
65.
Qualitative interviews on family and financial problems from 332 adolescents, young, middle-aged, and older adults, demonstrated that developmentally relevant goals predicted problem-solving strategy use over and above problem domain. Four focal goals concerned autonomy, generativity, maintaining good relationships with others, and changing another person. We examined both self- and other-focused problem-solving strategies. Autonomy goals were associated with self-focused instrumental problem solving and generative goals were related to other-focused instrumental problem solving in family and financial problems. Goals of changing another person were related to other-focused instrumental problem solving in the family domain only. The match between goals and strategies, an indicator of problem-solving adaptiveness, showed that young individuals displayed the greatest match between autonomy goals and self-focused problem solving, whereas older adults showed a greater match between generative goals and other-focused problem solving. Findings speak to the importance of considering goals in investigations of age-related differences in everyday problem solving.  相似文献   
66.
A commonly used screening tool for psychopathology, the Brief Symptom Inventory, provides normative data for assessing current mental functioning across multiple domains. Using data from 654 psychiatric inpatients, receiver operating characteristic (ROC) analyses were conducted for three scales, Depression, Paranoid Ideation, and Psychoticism. t ratios identified significant group differences on the Depression scale between patients diagnosed with or without depression but no differences on the Paranoid Ideation and Psychoticism scales between patients diagnosed with or without schizophrenia. Area under the curve for Depression was .65, indicating that the scale improved diagnostic prediction somewhat beyond chance; for Paranoid Ideation, the area was .52 and for Psychoticism, the area was .53, indicating that these two scales did not significantly improve diagnostic prediction beyond chance.  相似文献   
67.
This paper deals with French norms for mental image versus picture agreement for 138 pictures and the imagery value for 138 concrete words and 69 abstract words. The pictures were selected from Snodgrass et Vanderwart's norms (1980). The concrete words correspond to the dominant naming response to the pictorial stimuli. The abstract words were taken from verbal associative norms published by Ferrand (2001). The norms were established according to two variables: 1) mental image vs. picture agreement, and 2) imagery value of words. Three other variables were controlled: 1) picture naming agreement; 2) familiarity of objects referred to in the pictures and the concrete words, and 3) subjective verbal frequency of words. The originality of this work is to provide French imagery norms for the three kinds of stimuli usually compared in research on dual coding. Moreover, these studies focus on figurative and verbal stimuli variations in visual imagery processes.  相似文献   
68.
69.
Childhood depressive conditions have been explored from multiple theoretical approaches but with few empirical attempts to address the interrelationships among these different domains and their combined effects. In the present study, the authors examined different pathways through which social, cognitive, and genetic risk factors may be expressed to influence depressive symptoms in 300 pairs of child twins from a longitudinal study. Path analysis supported several indirect routes. First, risks associated with living in a step- or single-parent family and punitive parenting did not directly influence depressive outcome but were instead mediated through maternal depressive symptoms and child negative attributional style. Second, the effects of negative attributional style on depressive outcome were greatly exacerbated in the presence of precipitating negative life events. Third, independent of these social and cognitive risk mechanisms, modest genetic effects were also implicated in symptoms, with some indication that these risks are expressed through exposure to negative stressors. Together, these routes accounted for approximately 13% of total phenotypic variance in depressive symptoms. Theoretical and analytical implications of these results are discussed in the context of several design-related caveats.  相似文献   
70.
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