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Alden E. Gaertner Jamie L. Rathert Paula J. Fite Michael Vitulano Porché T. Wynn Jennifer Harber 《Journal of child and family studies》2010,19(5):607-616
Previous research demonstrates that aspects of parenting interact to influence child adjustment. We aimed to extend this research
by examining parenting strategies associated with behavioral control, specifically sources of parental knowledge regarding
child behavior (child disclosure, parental solicitation, parental control), as moderators of the relation between psychological
control and relational and physical/verbal aggression. Our sample included 89 children (56% male), ages 9–12. Consistent with
prior research on child adjustment, low child disclosure was the only source of parental knowledge associated with both relational
and physical/verbal aggression. Moreover, parental solicitation moderated the association between psychological control and
relational, but not physical, aggression. That is, at high levels of parental solicitation, psychological control and relational
aggression were positively related, whereas at low levels of parental solicitation, psychological control and relational aggression
were unrelated. Implications and future directions are discussed. 相似文献
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In two experiments that we conducted with adult (Experiment 1) and child (Experiment 2) participants, we experimentally controlled
the eyes' first fixation in the word using a variable viewing-position technique in a classical all-letter-coloring Stroop
procedure. We explored the impact of initial-fixation position (optimal viewing position [OVP] vs. end of the word) on the
magnitude of Stroop effects (both interference and facilitation). The results showed that both interference and facilitation
effects were reduced when the first fixation was located at the end of the word rather than at the OVP. These data make a
new contribution to the study of the role of low-level processes in Stroop effects and add support to the growing body of
research indicating that oculomotor processes can act as moderators of cognitive processes in the determination of Stroop
effects. 相似文献
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Sonal Goswami Michele Cascardi Olga E. Rodríguez-Sierra Sevil Duvarci Denis Paré 《Learning & memory (Cold Spring Harbor, N.Y.)》2010,17(10):494-501
Humans with post-traumatic stress disorder (PTSD) are deficient at extinguishing conditioned fear responses. A study of identical twins concluded that this extinction deficit does not predate trauma but develops as a result of trauma. The present study tested whether the Lewis rat model of PTSD reproduces these features of the human syndrome. Lewis rats were subjected to classical auditory fear conditioning before or after exposure to a predatory threat that mimics a type of traumatic stress that leads to PTSD in humans. Exploratory behavior on the elevated plus maze 1 wk after predatory threat exposure was used to distinguish resilient vs. PTSD-like rats. Properties of extinction varied depending on whether fear conditioning and extinction occurred before or after predatory threat. When fear conditioning was carried out after predatory threat, PTSD-like rats showed a marked extinction deficit compared with resilient rats. In contrast, no differences were seen between resilient and PTSD-like rats when fear conditioning and extinction occurred prior to predatory threat. These findings in Lewis rats closely match the results seen in humans with PTSD, thereby suggesting that studies comparing neuronal interactions in resilient vs. at-risk Lewis rats might shed light on the causes and pathophysiology of human PTSD.Following a severe traumatic event, some individuals manifest a syndrome, known as post-traumatic stress disorder (PTSD), characterized by repeated painful recollection of the trauma, avoidance of trauma reminders, intrusive thoughts, startle, hyperarousal, and disturbed sleep. Lifetime prevalence of PTSD ranges from 1.4% to 11.2% in representative samples (Afifi et al. 2010). Review of heritability studies indicate that there is a significant genetic component to PTSD (Nugent et al. 2008) as shared genes explain approximately 25%–38% of variability in PTSD symptom clusters and total symptoms (Afifi et al. 2010). Moreover, PTSD heritability coincides with that of other psychiatric conditions such as generalized anxiety, panic disorder, and depression (Chantarujikapong et al. 2001; Fu et al. 2007), suggesting that these disorders gain expression through common biological pathways.Although our understanding of PTSD has improved recently, we still have a limited grasp of the factors that predispose some to be at risk for PTSD, as well as those contributing to PTSD expression following trauma. In part, this situation results from the ethical limitations associated with human studies. For example, humans cannot be randomly assigned to trauma, and, importantly, the invasive techniques required to study the pathophysiology of PTSD can be used only in animals. Thus, a promising approach toward understanding the underlying pathophysiology of PTSD would be to study the disease in a valid animal model of the human syndrome.Fortunately, much work has already been performed to define an animal model of PTSD that reproduces the salient features of the human syndrome (see Adamec et al. 2006; Cohen et al. 2006a; Siegmund and Wotjak 2006). The most promising research has focused on the impact of exposing rodents to species-relevant threatening stimuli that mimic the kind of life-and-death circumstances that precipitates PTSD in humans. Indeed, rodents exposed to predators or their odor develop long-lasting (3 wk or more) manifestations of anxiety as seen in a variety of behavioral assays including the elevated plus maze (EPM), social interaction test, and acoustic startle (Adamec and Shallow 1993; Blanchard et al. 2003; Adamec et al. 2006). The inherent strength of this species-relevant stimulus was demonstrated in studies where predator odor served as an unconditioned stimulus to support cued or contextual fear conditioning (Blanchard et al. 2001; McGregor et al. 2002). As is the case with human PTSD, differential vulnerability to predatory threat was also observed in rodents. In one study, for instance, the propensity of different strains of rats to develop extreme behavioral manifestations of anxiety (EBMAs) as a result of predatory threat has been characterized, revealing that a much higher proportion (50%) of Lewis rats (an inbred strain) develops EBMAs as a result of an intense predatory threat compared with 10% of Fisher rats and 20% of Sprague–Dawley rats (Cohen et al. 2006b).Although these results are promising, it remains unclear whether Lewis rats also exhibit traits that parallel the pathophysiology of human PTSD. One such factor, thought to play a particularly critical role in the persistence of PTSD, is a compromised ability to extinguish fear memories (for review, see Quirk and Mueller 2008). Two main lines of evidence support this notion. First, in functional imaging studies, the brain structures that normally support fear expression and extinction (for review, see Pape and Pare 2010) show abnormal activity patterns in PTSD (Rauch et al. 2006; Shin et al. 2006; Bremner et al. 2008; Milad et al. 2009). Second, several studies have reported that individuals with PTSD are deficient at extinguishing classically conditioned fear responses (Orr et al. 2000; Peri et al. 2000; Blechert et al. 2007; Milad et al. 2008, 2009). Of particular interest, a study of identical twins discordant for trauma exposure has revealed that this extinction deficit was not a pre-existing condition but developed as a result of trauma (Milad et al. 2008). Given the possibility that an inability to extinguish fear might contribute to the maintenance of PTSD, we therefore tested whether Lewis rats reproduced the properties of extinction seen in human PTSD. 相似文献
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A. Huerta-Rivas G. Pérez-García C. González-Espinosa A. Meneses 《Neurobiology of learning and memory》2010,93(1):99-110
Growing evidence indicates that antagonists of the 5-hydroxytryptamine (serotonin) receptor6 (5-HT6) improve memory and reverse amnesia although the mechanisms involved are poorly understood. Hence, in this paper RT-PCR was used to evaluate changes in mRNA expression of 5-HT6 receptor in trained and untrained rats treated with the 5-HT6 receptor antagonist SB-399885 and amnesic drugs scopolamine or dizocilpine. Changes in mRNA expression of 5-HT6 receptor were investigated at different times in prefrontal cortex, hippocampus and striatum. Data indicated that memory in the Pavlovian/instrumental autoshaping task was a progressive process associated to reduced mRNA expression of 5-HT6 receptor in the three structures examined. SB-399885 improved long-term memory at 48 h, while the muscarinic receptor antagonist scopolamine or the non-competitive NMDA receptor antagonist dizocilpine impaired it at 24 h. Autoshaping training and treatment with SB-399885 increased 5-HT6 receptor mRNA expression in (maximum increase) prefrontal cortex and striatum, 24 or 48 h. The scopolamine-induced amnesia suppressed 5-HT6 receptor mRNA expression while the dizocilpine-induced amnesia did not modify 5-HT6 receptor mRNA expression. SB-399885 and scopolamine or dizocilpine were able to reestablish memory and 5-HT6 receptor mRNA expression. These data confirmed previous memory evidence and of more interest is the observation that training, SB-399885 and amnesic drugs modulated 5-HT6 receptor mRNA expression in prefrontal cortex, hippocampus and striatum. Further investigation in different memory tasks, times and amnesia models together with more complex control groups might provide further clues. 相似文献
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Jelle Demanet Frederick Verbruggen Baptist Liefooghe André Vandierendonck 《Psychonomic bulletin & review》2010,17(3):387-393
The present study investigated the relative contribution of bottom-up and top-down control to task selection in the voluntary
task-switching (VTS) procedure. In order to manipulate the efficiency of top-down control, a concurrent working memory load
was imposed during VTS. In three experiments, bottom-up factors, such as stimulus repetitions, repetition of irrelevant information,
and stimulus-task associations, were introduced in order to investigate their influence on task selection. We observed that
the tendency to repeat tasks was stronger under load, suggesting that top-down control counteracts the automatic tendency
to repeat tasks. The results also indicated that task selection can be guided by several elements in the environment, but
that only the influence of stimulus repetitions depends on the efficiency of top-down control. The theoretical implications
of these findings are discussed within the interplay between top-down and bottom-up control that underlies the voluntary selection
of tasks. 相似文献
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David Dardou Frédérique Datiche Martine Cattarelli 《Neurobiology of learning and memory》2010,93(1):137-150
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
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