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151.
Identification of the second of two targets (T2) is impaired when presented shortly after the first (T1). This attentional blink (AB) is thought to arise from a delay in T2 processing during which T2 is vulnerable to masking. Conventional studies have measured T2 accuracy which is constrained by the 100% ceiling. We avoided this problem by using a dynamic threshold-tracking procedure that is inherently free from ceiling constraints. In two experiments we examined how AB magnitude is affected by three masking-related factors: (a) presence/absence of T2 mask, (b) T2-mask stimulus onset asynchrony (SOA), and (c) level of T2 impoverishment (signal-to-noise ratio [SNR]). In Experiment 1, overall accuracy decreased with T2-mask SOA. The magnitude of the AB, however, was invariant with SOA and with mask presence/absence. Experiment 2 further showed that the AB was invariant with T2 SNR. The relationship among mask presence/absence, SOA, and T2 SNR and the AB is encompassed in a qualitative model.  相似文献   
152.
Growing experimental evidence suggests that temporal events are represented on a mental time line, spatially oriented from left to right. Support for the spatial representation of time comes mostly from studies that have used spatially organized responses. Moreover, many of these studies did not avoid possible confounds attributable to target stimuli that simultaneously convey both spatial and temporal dimensions. Here we show that task-irrelevant, lateralized visuospatial primes affect auditory duration judgments. Responses to short durations were faster when the auditory target was paired with left- than with right-sided primes, whereas responses to long durations were faster when paired with right- than with left-sided primes. Thus, when the representations of physical space and time are concurrently activated, physical space may influence time even when a lateralized, spatially encoded response is not required by the task. The time-space interaction reported here cannot be ascribed to any Spatial-Temporal Association of Response Codes effect. It supports the hypothesis that the representation of time is spatially organized, with short durations represented on the left space and longer ones on the right.  相似文献   
153.
This study examines the relational model of self-supporting personality, enacted social support, and perceived social support in a sample of 482 Chinese high school students using the Self-Supporting Personality Scale for Adolescent Students (SSPS-AS), the Social Support Rating Scale (SSRS), and the Multidimensional Scale of Perceived Social Support (MSPSS). Results from the cross-sectional structural equation analyses revealed that interpersonal initiative, interpersonal openness, personal openness and personal initiative predicted perceived social support through the mediating role of enacted social support, while interpersonal responsibility, interpersonal flexibility, and personal initiative predicted perceived social support directly. Thus, the hypothesized relational model of personality, enacted social support, and perceived social support was supported. The positive relational schema may be the main underpinning of the relation of self-supporting personality, enacted social support, and perceived social support. Culture also may influence the relation.  相似文献   
154.
The purpose of this study was to investigate the hypothesis that a self-organized criticality (SOC) practice condition would have a higher improvement rate in performance outcome than a typical progressive difficulty of practice regimen. The roller ball task was used where participants undergo a phase transition from failure to successful performance after sufficient practice. The findings from two experiments showed that the SOC condition had the fastest rate of improvement and the highest performance success level. The success probability in the SOC practice regime was close to the theoretically predicted value of 50%. It appears that the SOC practice condition - by scaling task difficulty to skill level in a self-controlled adaptive strategy - facilitates the learning of new movement coordination pattern by keeping the participant close to the parameter region of the transition of the movement dynamics.  相似文献   
155.
With p and q each standing for a familiar event, a disjunctive statement, “either p or q”, seems quite different from its material conditional, “if not p then q”. The notions of sufficiency and necessity seem specific to conditional statements. It is surprising, however, to find that perceived sufficiency and necessity affect disjunctive reasoning in the way they affect conditional reasoning. With B and C each standing for a category name, a universal statement, “all B are C”, seems stronger than its logically equivalent conditional statement, “if B then C”. However, the effects of perceived sufficiency or necessity were found to be as pronounced in conditional reasoning as in syllogistic reasoning. Furthermore, two experiments also showed that (a) MP (modus ponens)-comparable disjunctive reasoning was as difficult as MT (modus tollens)-comparable disjunctive reasoning, and that (b) MT-comparable syllogisms were easier to solve than MT problems in conditional reasoning.  相似文献   
156.
This study examined the effects of visual-verbalload (as measured by a visually presented reading-memory task with three levels) on a visual/auditory stimulus-response task. The three levels of load were defined as follows: "No Load" meant no other stimuli were presented concurrently; "Free Load" meant that a letter (A, B, C, or D) appeared at the same time as the visual or auditory stimulus; and "Force Load" was the same as "Free Load," but the participants were also instructed to count how many times the letter A appeared. The stimulus-response task also had three levels: "irrelevant," "compatible," and "incompatible" spatial conditions. These required different key-pressing responses. The visual stimulus was a red ball presented either to the left or to the right of the display screen, and the auditory stimulus was a tone delivered from a position similar to that of the visual stimulus. Participants also processed an irrelevant stimulus. The results indicated that participants perceived auditory stimuli earlier than visual stimuli and reacted faster under stimulus-response compatible conditions. These results held even under a high visual-verbal load. These findings suggest the following guidelines for systems used in driving: an auditory source, appropriately compatible signal and manual-response positions, and a visually simplified background.  相似文献   
157.
The transtheoretical model proposes that behavior change is experienced as a series of stages. Interventions tailored to these stages are most likely to be effective in progressing people through the model's hypothesized behavior change continuum. In this study, a stage-tailored, 12-week, exercise behavior intervention based on the transtheoretical model was conducted among a sample of 150 Chinese youth with hearing loss. Participants were randomized into an intervention or control group with all the core transtheoretical model constructs assessed pre- and post-intervention. Participants in the intervention group showed greater advances in their stage of exercise behavior change, decisional balance, and processes of change use compared to those in the control group. The intervention, however, was insufficient for increasing participants' self-efficacy for exercise behavior. The findings partially support the utility of the theory-based intervention for improving the exercise behavior of Chinese youth with hearing loss, while simultaneously helping to identify areas in need of improvement for future applications.  相似文献   
158.
Inaction inertia describes the phenomenon that an individual is unlikely to act on an attractive opportunity after having bypassed an even more attractive one. The results of two experiments indicate that after missing an initial opportunity to obtain a product as a free gift during a promotional period, the inaction inertia effect reduces the likelihood of consumers buying the product at a discounted price (second, inferior opportunity), particularly if the free gift has a high regular price. Additionally, according to the results of Experiment 2, those consumers are less likely to buy a product that has been offered previously as a free gift when a greater total quantity of the free gift is offered during a promotional period. Moreover, the mediation analysis results indicate that anticipated regret and valuation significantly impact the mediating role of inaction inertia.  相似文献   
159.

Purpose

Bilingual aphasia generally affects both languages. However, the age of acquisition of the second language (L2) seems to play a role in the anatomo-functional correlation of the syntactical/grammatical processes, thus potentially influencing the L2 syntactic impairment following a stroke. The present study aims to analyze the influence of late age of acquisition of the L2 on syntactic impairment in bilingual aphasic patients.

Methods

Twelve late bilingual participants (speaking French as L2 and either English, German, Italian or Spanish as L1) with stroke-induced aphasia participated in the study. The MAST or BAT aphasia batteries were used to evaluate overall aphasia score. An auditory syntactic judgement task was developed and used to test participants syntactic performance.

Results

The overall aphasia scores did not differ between L1 and L2. In a multiple case analysis, only one patient had lower scores in L2. However, four patients presented significantly lower performances in syntactic processing in the late L2 than in their native language (L1). In these four patients the infarct was localized, either exclusively or at least partially, in the pre-rolandic region.

Conclusion

This pilot study suggests that, in late bilingual aphasics, syntactic judgment abilities may be more severely impaired in L2, and that this syntactic deficit is most likely to occur following anterior lesions.  相似文献   
160.
Background and Objectives: Although there is supporting evidence for the stress generation hypothesis (i.e., the tendency for depression-prone individuals to experience more negative dependent events influenced by their behaviors and characteristics), additional research is required to advance current understanding of the specific types of dependent events relevant to this effect. The present study elaborated on the stress generation hypothesis, in which the content of negative dependent events experienced by individuals is contingent upon, and matches, the nature of their particular vulnerabilities. This extension was tested within the context of Cole's competency-based model of depression. Design: Participants (n = 185) were assessed at two time-points separated by a four-month interval. Methods: Self-perceived competence in academic, social, and appearance domains at the initial time-point were examined in relation to negative life events prospectively occurring over the four-month follow-up period, assessed using the “contextual threat” method. Results: Partial support was obtained for vulnerability-specific stress generation. Stress-generation specificity was found for self-perceived competence in appearance and academic domains, but not for self-perceived social competence. Conclusions: The current findings are consistent with the possibility of a more complex relation between self-perceived social competence and domain-congruent stress generation. Individuals may be more likely to experience negative dependent events in domains matching their specific vulnerabilities.  相似文献   
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