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211.
It is widely assumed that reinforcers are biologically relevant stimuli, or stimuli that have been associated with biologically relevant stimuli. However, brief, arbitrary stimuli have also been reported to have reinforcement-like effects, despite being unrelated to biologically relevant stimuli like food. The present study explored the potential reinforcement-like effects of brief stimuli across 5 experiments. In Experiments 1 through 4, pigeon subjects responded for food reinforcement and brief stimulus presentations in a 2-component multiple schedule. Neither baseline response rates nor resistance to change during disruption tests were systematically greater in a component with versus without brief stimulus presentations. Increasing the rate and duration of brief stimulus presentations in Experiment 4 did not reveal reinforcement-like effects when compared directly with food. In Experiment 5, pigeons chose between independent terminal links in a concurrent-chains procedure. Across conditions, varying the location, duration, and rate of brief stimulus presentations in the terminal links had no systematic effects on preference. In contrast, varying rates of food reinforcers resulted in large and reliable shifts in preference. Therefore, the present study found no systematic evidence that brief stimuli unrelated to food reliably increase response rates, resistance to change, or preference. These data demonstrate the value of systematic replication, and a behavioral momentum approach to assessing potential reinforcement-like effects.  相似文献   
212.
The transition to university can be stressful for first-year university students. Despite the fact where the feeling of worry is a shared symptom by various mental health issues, there is a lack of studies that investigate into this matter. As worry is a domain-specific construct, there is a need for a valid and reliable measure of worry specifically for university students. Hence, this study aimed to evaluate the psychometric properties of the Student Worry Scale (SWS), particularly in terms of its validity and reliability. For this purpose, the current study recruited a sample of 295 first-year students to evaluate the psychometric properties of SWS. Exploratory factor analysis yielded a five-factor structure of SWS, which explained 55.7% of the total variance. The yielded five factors were general worries, financial-related concerns, significant other’s well-being, academic concerns, and social adequacy concerns. Inter-correlations between the five factors were all significant (r ranged between 0.395 and 0.625). The SWS demonstrated good internal consistency in this study (Cronbach’s alpha ranged between 0.786 and 0.941). Overall, the SWS is psychometrically evidenced to be a reliable and valid content-based worry measure specifically for university students.  相似文献   
213.
Past research showed that people project their goals onto unknown others. The present research investigates whether they also rely on their motivational orientation in terms of regulatory mode (locomotion vs. assessment). In line with work on self-judgments, a stronger chronic personal focus on locomotion over assessment decreased predictions of others' experiences of nostalgia (Study 1) and increased predictions of others' preference for, motivation by, and evaluation of a transformational over a transactional leader (Study 2). Furthermore, an experimentally induced locomotion mode compared to an assessment mode increased peoples' predictions of others' motivation to reconcile after interpersonal conflict (Study 3). We examined process evidence via the Testing-Process-by-Interaction-Strategy: As predicted, effects only emerged under time pressure (vs. ample deliberation; Study 2) and for ingroup (vs. outgroup) members (Study 3). These findings suggest that people's regulatory mode is a basis for predicting others' reactions and preferences. We discuss implications and future research directions.  相似文献   
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Rheumatoid arthritis (RA) prevalence increases with age and old people are special patient population. The recognition of functional disability related to RA could be challenging in elderly patients because aging itself and potential co-morbid disease may also cause functional disability. In this study, we aimed to look at the correlation between disease activity and functional disability in elderly RA patients. Elderly RA patients, ≥65 years old at their routine visits were included in the study. The composite ‘disease activity score’ in 28 joints (DAS-28) was used to determine disease activity groups. Health assessment questionnaire (HAQ) scores were calculated to describe the functional disability and compared across the disease activity groups. Two hundred and fifty-eight RA patients with the mean age of 71 ± 5 (65–90) and a total disease duration of 8.4 ± 8.5 (.5–50) years were recruited. The proportion of patients with high and moderate disease activity was 70%. HAQ scores were significantly correlated with disease activity (p < .05). Functional disability estimated by HAQ was correlated with disease activity in elderly patients with RA  相似文献   
216.
The Hidden Markov Modeling approach for eye-movement data analysis is able to quantitatively assess differences and similarities among individual patterns. Here we applied this approach to examine the relationships between eye-movement patterns in face recognition and age-related cognitive decline. We found that significantly more older than young adults adopted “holistic” patterns, in which most eye fixations landed around the face center, as opposed to “analytic” patterns, in which eye movements switched among the two eyes and the face center. Participants showing analytic patterns had better performance than those with holistic patterns regardless of age. Interestingly, older adults with lower cognitive status (as assessed by the Montreal Cognitive Assessment), particularly in executive and visual attention functioning (as assessed by Tower of London and Trail Making Tests) were associated with a higher likelihood of holistic patterns. This result suggests the possibility of using eye movements as an easily deployable screening assessment for cognitive decline in older adults.  相似文献   
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Examining how animals direct social learning during skill acquisition under natural conditions, generates data for examining hypotheses regarding how transmission biases influence cultural change in animal populations. We studied a population of macaques on Koram Island, Thailand, and examined model-based biases during interactions by unskilled individuals with tool-using group members. We first compared the prevalence of interactions (watching, obtaining food, object exploration) and proximity to tool users during interactions, in developing individuals (infants, juveniles) versus mature non-learners (adolescents, adults), to provide evidence that developing individuals are actively seeking information about tool use from social partners. All infants and juveniles, but only 49% of mature individuals carried out interacted with tool users. Macaques predominantly obtained food by scrounging or stealing, suggesting maximizing scrounging opportunities motivates interactions with tool users. However, while interactions by adults was limited to obtaining food, young macaques and particularly infants also watched tool users and explored objects, indicating additional interest in tool use itself. We then ran matrix correlations to identify interaction biases, and what attributes of tool users influenced these. Biases correlated with social affiliation, but macaques also preferentially targeted tool users that potentially increase scrounging and learning opportunities. Results suggest that social structure may constrain social learning, but the motivation to bias interactions towards tool users to maximize feeding opportunities may also socially modulate learning by facilitating close proximity to better tool users, and further interest in tool-use actions and materials, especially during development.  相似文献   
219.
This article investigates how test-takers change their strategies to handle increased test difficulty. An adult sample reported their test-taking strategies immediately after completing the tasks in a reading test. Data were analyzed using structural equation modeling specifying a measurement-invariant, ability-moderated, latent transition analysis in Mplus (Muthén & Asparouhov, 2011). It was found that almost half of the test-takers (47%) changed their strategies when encountering increased task-difficulty. The changes were characterized by augmenting comprehending-meaning strategies with score-maximizing and test-wiseness strategies. Moreover, test-takers' ability was the driving influence that facilitated and/or buffered the changes. The test outcomes, when reviewed in light of adjusted test-taking strategies, demonstrated a form of process-based validity evidence.  相似文献   
220.
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