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1.
Smokers and nonsmokers were compared on three aspects of academic achievement. Although exactly the same percentage of smokers and nonsmokers passed the first-year university examination, smokers obtained significantly higher marks. Similarly, smokers achieved significantly higher marks in their final year examinations in comparison with nonsmokers. Finally, a comparison of the tutorial essay marks of the smokers and nonsmokers again showed that smokers obtained significantly higher marks than nonsmokers. These data are consistent with the idea that ambitious students adopt smoking in the belief that it will help them study and sustain concentration.  相似文献   
2.
Although links have been found between parents’ and teachers’ (caregivers’) attitudes about aggressive behavior, their responses to aggressive behaviour in children, and those children’s own use of aggressive behaviour, most research has focused on primary and secondary school contexts and has examined the influence of parents and teachers separately. The current study explored both parents’ and teachers’ beliefs and intervention strategies for relational and physical aggression in early childhood settings. Teachers (N?=?18; Mage?=?34.8 years) and parents (N?=?68; Mage?=?32.2 years) were presented with vignettes portraying relational and physical aggression. Following each vignette, their perceptions of the seriousness of the act, empathy for the victim, likelihood to intervene, and intervention strategies used to respond to each vignette were assessed. Teachers were also interviewed about examples of aggression that have been seen in preschool age children. Results indicated that caregivers viewed relational compared to physical aggression as more normative, and had less empathy for, and were less likely to intervene in instances of relationally aggressive behaviour. They also recommended more passive intervention strategies towards relationally aggressive children and more direct strategies towards physically aggressive children. Interview responses indicated that teachers perceived the primary cause of aggression to be related to developmental characteristics of the child. Implications for how these findings about adult–child interactions impact the development of relational and physical aggression are discussed.  相似文献   
3.
Recognition memory, involving the ability to discriminate between a novel and familiar object, depends on the integrity of the perirhinal cortex (PRH). Glutamate, the main excitatory neurotransmitter in the cortex, is essential for many types of memory processes. Of the subtypes of glutamate receptor, metabotropic receptors (mGluRs) have received less study than NMDA receptors; thus, the reported experiments examined the role of mGluRs in familiarity discrimination in the rat PRH. Experiments 1 and 2 assessed the effects of systemic administration of MPEP, a group I mGluR (specifically mGluR5) antagonist, and/or LY341495, a group II mGluR antagonist, on a spontaneous object novelty preference task. Simultaneous antagonism of both group I and II mGluRs impaired familiarity discrimination following a 24-h but not a 15-min delay, while antagonism of either mGluR subtype alone had no effect at either delay. The impairment was in acquisition, as in Experiment 3 coadministration of MPEP and LY341495 did not affect recognition memory performance when administered either after the sample phase or prior to test. The impairment in long-term recognition memory was mediated by mGluRs in the PRH, as localized intracortical antagonism of group I and II mGluRs also produced a deficit (Experiment 4). No evidence was found for an involvement of group III mGluRs in the acquisition of long-term familiarity discrimination (Experiment 5). These findings establish that glutamatergic neurotransmission in the PRH via group I and II mGluRs is crucial for the acquisition, but not for the consolidation or retrieval of long-term object recognition memory.  相似文献   
4.
ObjectivesThis study aimed to examine the effects of change in perceived teacher achievement goal emphasis in physical education (PE) on physical self-perceptions and self-esteem across the transition to secondary school.Design & methodsA longitudinal design was adopted with three time points, one at the end of primary school and two during the first year of secondary school. Participants (N = 491) were cross-classified by primary (N = 42) and secondary (N = 46) PE class in order to examine the association between perceived class-level teacher-emphasised goals and within-class student goals with self-beliefs.ResultsPersonal approach goals and class perceptions of teacher mastery approach goal promotion were all positively associated with ratings of co-ordination, sport competence, flexibility, and endurance in primary school. More favourable perceptions of coordination, sport competence, strength, flexibility, and endurance during the first year of secondary school were predicted by an increase in performance approach goal emphasis, whereas ratings of sport competence and flexibility were negatively associated with an increase in mastery approach goal emphasis.ConclusionsAlthough not entirely consonant with theoretical predictions, current findings suggest that teacher-emphasised performance approach goals in PE can promote development of several physical self-perceptions in the initial year of secondary school.  相似文献   
5.
Object-in-place memory, which relies on the formation of associations between an object and the place in which it was encountered, depends upon a neural circuit comprising the perirhinal (PRH) and medial prefrontal (mPFC) cortices. This study examined the contribution of muscarinic cholinergic neurotransmission within this circuit to such object-in-place associative memory. Intracerebral administration of scopolamine in the PRH or mPFC impaired memory acquisition, but not retrieval and importantly we showed that unilateral blockade of muscarinic receptors simultaneously in both regions in opposite hemispheres, significantly impaired performance. Thus, object-in-place associative memory depends upon cholinergic modulation of neurones within the PRH-PFC circuit.Recognition memory enables individuals to judge whether stimuli have been encountered before. In its most basic form such judgments may be made on the basis of simply whether a stimulus is familiar or novel (familiarity discrimination). However, these judgments may also be made using associations formed between a stimulus and the location or environmental setting in which it was previously encountered. Such object-in-place associative memory in animals is of particular interest as it is acquired rapidly and it requires the integration of object and spatial information and thus has been described as an analog of human episodic memory (Wilson et al. 2008).The perirhinal cortex (PRH) in the medial temporal lobe is a critical neural structure for object recognition and object-in-place associative memory (Bussey et al. 2000; Barker et al. 2007), but unlike object recognition, this memory process is also dependent on the medial prefrontal cortex (mPFC) (Kesner and Ragozzino 2003; Browning et al. 2005; Barker et al. 2007) and crucially it has been shown to depend upon a functional interaction between the PRH and mPFC, with each region making a distinct cognitive contribution to the memory formation (Barker et al. 2007; Barker and Warburton 2008).Having identified two neural regions critical for object-in-place associative memory, we now extend our investigations to explore the underlying cellular mechanisms mediating acquisition or retrieval of this memory process. The present study focused on the neurotransmitter acetylcholine as cholinergic innervation of the PRH is crucial for familiarity discrimination (Tang et al. 1997; Easton and Gaffan 2001; Warburton et al. 2003; Abe et al. 2004; Winters and Bussey 2005). In contrast, the role of muscarinic receptor neurotransmission in the PRH or mPFC in object-in-place associative memory is unknown. Further, while it might appear that object recognition memory and object-in-place memory are likely to share common neural substrates, recent data from our laboratory suggest that this may not be the case (Griffiths et al. 2008).To explore the importance of muscarinic cholinergic neurotransmission within the PRH-mPFC circuit for object-in-place memory, rats were implanted with bilateral cannulae aimed at the PRH or mPFC or both regions to allow direct intracerebral administration of scopolamine during distinct stages of an object-in-place task. Memory performance was tested following either a short (5 min) or long (1 h) retention delay. All animal procedures were performed in accordance with the United Kingdom Animals Scientific Procedures Act (1986) and associated guidelines. Details of the surgery, infusion procedures, behavioral testing, and histology have been published previously (Barker and Warburton 2008). Briefly, male DA rats (230–250 g, Bantin and Kingman, UK) housed under a 12-h/12-h light/dark cycle (light phase 18:00–6:00 h), were anesthetized with isoflurane (induction 4%, maintenance 2%–3%) and surgically implanted with bilateral cannulae aimed at either the PRH or mPFC or both regions. After a two-week recovery period all rats were handled, habituated, and then tested in the object-in-place memory task.Sample phase: Each rat was placed in a black open-topped wooden arena (50 × 90 × 100 cm) containing four different objects (A, B, C, D) constructed from “Duplo” (Lego UK Ltd.). The walls of the arena were surrounded with a black cloth to a height of 1.5 m, and the floor covered with sawdust. The objects were placed 15 cm from the walls (see Fig. 1A) and each rat was allowed to explore the objects for 5 min, after which it was removed for the delay (5 min or 1 h). Exploratory behavior was defined as the animal directing its nose toward the object at a distance of <2 cm. Any other behavior, such as looking around while sitting on or resting against the object, was not recorded. Subjects that failed to complete a minimum of 15-s exploration in the sample phase or 10 s of exploration in the test phase were excluded from the analysis.Open in a separate windowFigure 1.Diagrammatic representations of the individual infusion sites in each animal. (A) Bilateral medial prefrontal (mPFC) group. (B) Bilateral perirhinal (PRH) group. (C) The mPFC infusion sites of the PRH+mPFC group. (D) The PRH infusion sites of the PRH+mPFC group. All of the infusion sites were within the PRH or mPFC.Test phase: Two of the objects, e.g., B and D, exchanged positions and the subjects were replaced in the arena for 3 min. The time spent exploring the two objects that had changed position was compared to the time spent exploring the two objects that had remained in the same position. If object-in-place memory is intact, subjects spend more time exploring the “moved” objects, compared to the “unmoved” objects. Scopolamine hydrobromide (Sigma-Aldrich) dissolved in sterile 0.9% saline solution was administered at a dose of 10 μg/μL per hemisphere (Schroeder and Packard 2002; Warburton et al. 2003; Winters et al. 2006); control infusions consisted of saline. The infusions were given either 15 min before the sample phase or 15 min before the test phase. At the end of the experiment, each rat was anesthetized and perfused transcardially. Coronal brain sections (40 μm) were stained with cresyl-violet to verify the cannulae locations. All the rats in the PRH group had the tip of the bilateral cannulae in the PRH and all the rats in the mPFC group had tips in the ventral portion of the prelimbic or dorsal portion of the infralimbic region of the prefrontal cortex (Fig. 1B). From unpublished observations, using Indian ink and radiolabeled scopolamine, the region infused is estimated to be 1–1.5 mm3, and largely confined to perirhinal cortex or the prelimbic/infralimbic regions of the prefrontal cortex. This spread is consistent with previously quoted results in other brain regions (Martin 1991; Izquierdo et al. 2000; Attwell et al. 2001). Figure 2, A and B show the performance of the rats receiving bilateral infusions of scopolamine or vehicle into either the PRH (n = 12) or mPFC (n = 12) 15 min prior to the sample phase. After a minimum of 48 h, vehicle or scopolamine was infused in a cross-over design and the animal retested using different objects. A three-way ANOVA (drug × region × delay) showed that scopolamine infusion into either region significantly impaired the acquisition of object-in-place memory (main effect of drug F (1,35) = 63.87, P < 0.001). The magnitude of the deficit was similar irrespective of the region into which scopolamine was infused (region F (1,35) < 1.0) or the delay employed (delay F (1,35) < 1.0). Further analyses to examine whether individual groups discriminated between the objects, using a within subjects t-test (two-tailed), confirmed that vehicle-treated animals in the PRH and mPFC groups showed a significant preference for the moved objects over the objects that had remained in the same position, irrespective of the retention delay (PRH 5 min t (9) = 2.96, P < 0.02; 1 h t (10) = 5.71, P < 0.001: mPFC 5 min t (5) = 5.47, P < 0.005; 1 h t (11) = 9.89, P < 0.001), while scopolamine infusion into the PRH or mPFC significantly disrupted the animal''s ability to discriminate (PRH 5min t (9) = 0.13, P = 0.9; 1 h t (10) = 0.92, P = 0.38: mPFC 5 min t (5) = 0.051, P = 0.961; 1 h t (11) = 0.68, P = 0.51). Scopolamine was without effect on the total amount of exploration completed in the sample or test phases (all Fs < 1.0).Open in a separate windowFigure 2.Discrimination between the objects was calculated using a discrimination ratio, which takes into account individual differences in the total amount of exploration. The discrimination ratio is calculated as follows: the difference in time spent by each animal exploring objects that changed position compared to the objects that remained in the same position divided by the total time spent exploring all objects. (A) Infusion of scopolamine (Scop) into the perirhinal cortex (PRH) significantly impaired performance in the object-in-place task following a 5 min and a 1 h delay. (B) Infusion of scopolamine (Scop) into the medial prefrontal cortex (mPFC) significantly impaired performance in the object-in-place task following a 5 min and a 1 h delay. Illustrated for each group is the mean (+ SEM) discrimination ratio. * P < 0.05; ** P < 0.01; and *** P < 0.001 difference between groups.It could be argued that the impairment produced by intracortical infusions of scopolamine following a short delay, reflects an effect on retrieval as well as acquisition. Therefore, we examined the effect of pretest administration of scopolamine (infusion 15 min before the start of the test phase) in the mPFC or PRH following a 1 h delay. No significant impairments were found (mean discrimination ratio ± SEM: PRH vehicle 0.38 ± 0.07, scopolamine 0.46 ± 0.11; mPFC vehicle 0.37 ± 0.08, scopolamine 0.44 ± 0.05), confirmed by a nonsignificant drug effect (F (1,14) < 1.0, P > 0.1) and nonsignificant drug × area interaction (F (1,14) = <  1.0, P > 0.1). In addition all groups significantly discriminated between the moved objects compared to objects in the same location (PRH vehicle t (7) = 4.95, P < 0.01; PRH scopolamine t (7) = 3.45, P < 0.05; mPFC vehicle t (7) = 4.26, P < 0.01; mPFC scopolamine t (7) = 8.37, P < 0.01). Scopolamine was without effect on the total amount of exploration completed in the test phase (drug × region F (1,14) < 1.0, P > 0.05).To evaluate the importance of intrahemispheric interactions between these cortical regions and the cholinergic system, a third group of animals had cannulae implanted into both the PRH and mPFC (n = 12). In this experiment the behavioral effects of unilateral scopolamine infusions into the PRH and mPFC in the same hemisphere (Scop Ipsi) were compared with the effects of unilateral scopolamine infusions into opposite hemispheres (Scop Contra). The animals assigned to the Scop Ipsi group on day one, received infusions into opposite hemispheres (Scop Contra) on day two (minimum of 48 h later). Likewise, the animals in the Scop Contra group on day one, received ipsilateral infusions on day two. Figure 3 shows discrimination performance following a 5 min or 1 h delay. A two-way within-subject ANOVA revealed that the Scop Contra group was significantly impaired (infusion F (1,20) = 44.35, P < 0.001) irrespective of the delay (infusion × delay F (1,20) < 1.0, P < 0.05). Further analysis confirmed that the Scop Contra group failed to discriminate between the moved and unmoved objects (5 min t (10) = 0.70, P > 0.1; 1 h t (10) = 1.03, P > 0.1), while the Scop Ipsi group preferentially explored the moved objects (5 min t (10) = 9.99, P < 0.0001; 1 h t (10) = 4.34, P = 0.001).Open in a separate windowFigure 3.Unilateral scopolamine infusions into the PRH and mPFC in opposite hemispheres (Scop Contra) impaired object-in-place performance following both a 5 min and a 1 h delay. Scopolamine infusions into both the PRH and mPFC in the same hemisphere (Scop Ipsi) had no effect on performance following either delay. ** P < 0.01 and *** P < 0.001 difference between groups.Scopolamine was without effect on overall exploration levels during the sample (infusion × delay F (1,20) < 1.0, P > 0.05; infusion F (1,20) < 1.0, P > 0.05; delay F (1,20) < 1.0, P > 0.05) or test phases (infusion × delay F (1,20) < 1.0, P  >  0.05; infusion F (1,20)  <  1.0, P > 0.05). There was a significant main effect of delay (F (1,20) = 10.67, P < 0.01), as the Scop Ipsi and Scop Contra groups completed a greater amount of exploration in the test phase following a 1 h delay compared to a 5 min delay.These results demonstrate that acquisition, but not retrieval of object-in-place memory, is dependent upon muscarinic cholinergic neurotransmission in both the mPFC and PRH. Thus, acute bilateral administration of scopolamine directly into the mPFC or PRH before the sample phase impaired both short- and long-term memory performances. In contrast administration of scopolamine into either the mPFC or PRH prior to the test phase had no effect. Significantly, co-administration of scopolamine into the PRH and mPFC in opposite hemispheres produced a significant impairment in both short-term and long-term object-in-place memory compared to performance following co-administration of scopolamine into the PRH and mPFC in the same hemisphere. Thus, concomitant activation of cholinergic muscarinic receptors is necessary in both regions for the formation of object-in-place associative recognition memory.Our previous studies investigating the role of the mPFC and PRH in object-in-place associative memory suggest that these regions make different cognitive contributions to this mnemonic process. Thus, the PRH appears to be primarily involved in the acquisition of “object” information, while we have hypothesized that the role of the mPFC is to integrate object and place information (Barker et al. 2007). As administration of scopolamine into either region disrupted performance following a long- or short-retention delay, the present data suggest that the neural mechanisms underlying both these different cognitive processes must be dependent upon cholinergic neurotransmission.The results demonstrate that muscarinic receptor neurotransmission is clearly critical for acquisition of the object-in-place task as no impairment was produced when scopolamine was administered only prior to the test phase. While the current study is the first to investigate the importance of cholinergic neurotransmission in object-in-place associative memory, a number of previous studies have shown that intra-PRH infusions of scopolamine block discrimination of novel and familiar objects when administered prior to the sample phase, but not when administered immediately after the sample phase or prior to the test phase (Aigner and Mishkin 1986; Aigner et al. 1991; Warburton et al. 2003; Winters et al. 2006). Thus, together these results support the hypothesis that muscarinic cholinergic neurotransmission within the PRH is necessary for encoding representations of new visual stimuli for subsequent recognition (Turchi et al. 2005), but not for the retrieval of such information. The present results also show for the first time that muscarinic receptor neurotransmission within the mPFC is crucial for the encoding, but not the retrieval of object-in-place memory.It may be argued that the disruptions in performance following administration of scopolamine reflect disruptions in attentional processing. Indeed muscarinic cholinergic neurotransmission in the prefrontal cortex has been implicated in both mnemonic and attentional processes (Voytko et al. 1994; Everitt and Robbins 1997; Chudasama et al. 2004; Dalley et al. 2004). However, deficits in attentional processing are typically observed when the attentional demands of the tasks are high, for example, when very short (millisecond) stimulus exposure times are used (Chudasama et al. 2004; Dalley et al. 2004). In the present study, the exposure time to the stimuli is relatively long (minutes); further there was no evidence of a drug-associated change in explorative behavior following either an infusion into the mPFC or PRH or simultaneously into both regions. Thus, it seems unlikely that the impairments in memory observed can be attributed purely to an attentional deficit, although it is possible that during the encoding of the object-in-place task attentional processes are also recruited involving the cholinergic afferents to the mPFC or PRH.The results showing that simultaneous muscarinic cholinergic blockade in the PRH and mPFC produces a significant impairment in performance support our previous findings of a neural system for object-in-place memory and extend these findings to show that cholinergic neurotransmission is a key component within the system. Our results also support those studies in primates demonstrating a circuit involving the basal forebrain, frontal cortex, and inferior temporal cortex is necessary for object memory encoding (Easton et al. 2002; Easton and Parker 2003).Results from our laboratory have shown that the maintenance of long-term, but not short-term, object-in-place memory is critically dependent upon concurrent NMDA receptor activation in the PRH and mPFC (Barker and Warburton 2008), while short-term object-in-place performance is dependent upon kainate receptor activation in the PRH. Hence, we have argued that there may be multiple cellular mechanisms underlying encoding of information for the short or long term. The present study contrasts with these findings as it demonstrates the necessity for muscarinic receptor activation for both short- and long-term object-in-place memory. Primate studies have indicated that a synergistic interaction between the cholinergic and glutamatergic systems plays an important role in the regulation of visual recognition memory (Matsuoka and Aigner 1996). Hence, further investigations are warranted to explore such interactions in the rat; for example, an interaction between NMDA and muscarinic receptor neurotransmission may mediate long-term recognition memory, while a kainate–muscarinic receptor interaction may mediate short-term recognition memory. Further, the extent to which the contribution of the cholinergic system to encoding of object-in-place memory within the PRH-mPFC system is the same for both short- or long-term memory is unknown.Our results have demonstrated that when a subject is required to use information concerning an association between an object and a place to produce a behavioral response, muscarinic cholinergic receptors in the mPFC are involved. Further, the object-in-place task requires the subject to acquire and remember the topographical relationship between the objects, a process that is known to depend upon the parietal cortex (Goodrich-Hunsaker et al. 2005). The precise contribution of object and spatial information processing in the parietal cortex to the operation of the PRH-mPFC circuit has yet to be determined.In conclusion, the cholinergic projections to the PRH and mPFC originating in the basal forebrain (Wenk et al. 1980) are an important component of the neural mechanisms underlying short- and long-term object-in-place associative memory.  相似文献   
6.

Objective

The purpose of this study was to synthesize findings from motivational climate interventions employing [Ames, 1992a] and [Ames, 1992b] and [Epstein, 1988] and [Epstein, 1989] TARGET framework within school-based physical education contexts.

Design

The present study employed a quantitative research synthesis design. Meta-analysis uses empirical studies to summarize past research by drawing overall conclusions from separate investigations. This research design highlights important and unsolved issues related to motivational climate interventions within physical education.

Methods

Standard meta-analytic procedures incorporating inclusion and exclusion criteria, literature search, coding procedures, and statistical methods were used to identify and synthesize 22 studies with 24 independent samples. Cohen’s (1988) criteria for effect sizes were used to interpret and evaluate results.

Results

There was an overall small positive treatment effect (g = 0.103) for groups exposed to mastery motivational climates. Outcome analyses identified the most consistent and largest overall treatment effects for behavioral outcomes (g = 0.39–0.49) followed by affective outcomes (g = −0.27 to 0.59) and cognitive outcomes (g = −0.25 to 0.32). Moderator analyses were directed by study heterogeneity and identified several trends in intervention features and study features with the most substantial trend for participant features as elementary students had the largest overall treatment effect (g = 0.41).

Conclusions

Outcome and moderator analyses identified several trends in methodological features, participant features, and study features that should be addressed in future physical education motivational climate interventions.  相似文献   
7.
Rats were trained with a tone, light or a tone--light combination as the discriminative stimulus. These groups were tested after doses of scopolamine and it was found that groups trained with a single cue were more sensitive to the drug than double-cue groups, although their pre-drug responding was similar. A similar pattern was found among individuals in the double-cue groups in which there was a significant correlation between dependency on a single cue, as shown in transfer tests, and drug sensitivity. These results were interpreted in terms of scopolamine-induced changes in stimulus sensitivity produced by a modification of the neural mechanisms controlling attention.  相似文献   
8.
This study utilized the California Psychological Inventory (CPI) and the Gough Adjective Check List (ACL) in an investigation of the relationship between personality characteristics and academic achievement in gifted university women. Several scales of the CPI differentiated achievers from underachievers. In addition, achieving and underachieving women described themselves differently on the ACL. As defined in this study, the achieving women were more highly socialized than the underachieving women.  相似文献   
9.
10.
This study has dual aims. First, it aims to explore the relationship between generativity and political participation, a neglected aspect of civic participation. Second, using different dimensions of generativity in a mixed methods study, it also aims to contribute to the theoretical and methodological literature on generativity as a multidimensional concept relevant to later life. This Spanish study involved a large survey utilising three different measures of generativity—generative concern, generative goals, and perceived cultural demands—to look for differences between older people actively engaged in political organisations and a comparison group. Results showed that older people from the two groups differed on all dimensions of generativity. Participants in political organisations showed significantly higher scores on generative concern, reported more generative goals in the present and future, and noted more perceived generative demands than comparison individuals. Overall, our findings suggest that generativity plays a key role in political engagement in later life, and, further, that our understanding of generativity in later life gains from a multidimensional assessment of the concept.  相似文献   
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