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911.
This study evaluated the prevalence of Internet addiction (IA) and its association with negative psychological symptoms in Brazilian adults. A network analysis was conducted to estimate specific variables and their expected influence on IA. In this cross-sectional study, 15,476 adults (Mage = 37.5, SD = 9.59) completed an open web-based survey. Three questionnaires were used: the Internet Addiction Test (IAT), Depression Anxiety and Stress Scale (DASS-21) and Satisfaction With Life Scale (SWLS). Based on IAT scores, participants were classified as No-Risk user (NRU), Low-Risk user (LRU) or High-Risk user (HRU). We observed that 4.8% of the participants were classified in the HRU group. In addition, their risk for severe symptoms of depression was 10 times higher and, for anxiety, seven times higher than that in the NRU group (p < .001). Time spent using smartphones was also significantly higher in the HRU group (Mhours = 5.1, p < .001). The main factors associated with IA were depression, gender and anxiety, but the variable “having children” was the most influential in the IA network. These findings suggest that psychiatric symptoms are the main factors associated with IA among the adult population.  相似文献   
912.
The present study investigated whether the Go/No-Go procedure with compound stimuli produces emergent relations among dictated words (A), pictures (B), and printed words (C) and the emergence of textual behavior (CD) using a multiple probe design across word sets. Three preschool children were exposed to 4 phases: (1) pretests for BC, CB, and CD relations, (2) pretraining with known stimuli, (3) AB and AC training, and (4) posttests for BC, CB, and CD relations. During AB and AC training, responses to A1B1, A2B2, A1C1, and A2C2 compound stimuli, but not to A1B2, A2B1, A1C2, and A2C1, were reinforced. The results showed that all participants met the learning criterion and demonstrated emergence of BC and CB relations (i.e., relations between pictures and printed words), and CD relations (i.e., textual behavior) after training. These results suggest that the Go/No-Go procedure with compound stimuli is an effective alternative for establishing reading comprehension.  相似文献   
913.
914.
The emergence of the COVID-19 pandemic in 2019 forced an abrupt shift in the modality through which psychotherapy was delivered and online therapy became the only viable option for clients. Research regarding experiences of online therapy during the early stages of the COVID-19 pandemic is minimal, however, and has largely focussed on therapists' experiences of delivering online treatment, as opposed to clients' experiences of receiving it. A scoping review was undertaken to establish what is known from the existing literature about clients' experiences of online therapy during the initial stages of the COVID-19 pandemic and identify gaps in the current knowledge. Searches were conducted across four academic databases: Scopus, EBSCO CINAHL Complete, EBSCO MEDLINE and OVID PsycInfo; the literature was excluded based on established PICOS criteria. Data were summarised through data charting and synthesised by way of inductive content analysis. A total of five articles were identified. All articles focussed on online therapy using video or audio conferencing, and four of the five studies examined clients with eating disorders. Inductive content analysis identified seven categories, as follows: preference for face-to-face therapy; appreciation of accessibility and convenience; online format hindered connection; positive experience of online therapy; individual client differences impacted experience; strong therapeutic alliance indicative of positive experience; and gratitude for continuation of treatment. Future research could explore clients' experiences of online therapy in a “post-pandemic” world and include a broader range of client populations and online therapy approaches in the COVID-19 context.  相似文献   
915.
In Islamic culture, there is an imperative demand that women should be virgins on their wedding night. Service providers in The Netherlands are increasingly confronted by Islamic young women who find themselves in serious difficulties because they are no longer virgins, and are about to enter a forced or arranged marriage. These young women report a diversity of problems such as loneliness, social isolation, depression, despair, suicidal feelings, identity problems and serious conflicts with parents. In this article we focus attention on the circumstances that can result in these types of difficulties, and also critically consider the kinds of help that young Islamic women are given. Attention is paid to the question of whether existing forms of service provision, especially surgical reconstruction of the hymen, take sexual and other inequalities into account.  相似文献   
916.
The authors tested for predominant patterns of coordination in the combination of rhythmic flexion-extension (FE) and supination- (SP) at the elbow-joint complex. Participants (N=10) spontaneously established in-phase (supination synchronized with flexion) and antiphase (pronation synchronized with flexion) patterns. In addition, the authors used a motorized robot arm to generate involuntary SP movements with different phase relations with respect to voluntary FE. The involuntarily induced in-phase pattern was accentuated and was more consistent than other patterns. The result provides evidence that the predominance of the in-phase pattern originates in the influence of neuromuscular-skeletal constraints rather than in a preference dictated by perceptual-cognitive factors implicated in voluntary control. Neuromuscular-skeletal constraints involved in the predominance of the in-phase and the antiphase patterns are discussed.  相似文献   
917.
Three pigeons chose between random-interval (RI) and tandem, continuous-reinforcement, fixed-interval (crf-FI) reinforcement schedules by pecking either of two keys. As long as a pigeon pecked on the RI key, both keys remained available. If a pigeon pecked on the crf-FI key, then the RI key became unavailable and the crf-FI timer began to time out. With this procedure, once the RI key was initially pecked, the prospective value of both alternatives remained constant regardless of time spent pecking on the RI key without reinforcement (RI waiting time). Despite this constancy, the rate at which pigeons switched from the RI to the crf-FI decreased sharply as RI waiting time increased. That is, prior choices influenced current choice-an exercise effect. It is argued that such influence (independent of reinforcement contingencies) may serve as a sunk-cost commitment device in self-control situations. In a second experiment, extinction was programmed if RI waiting time exceeded a certain value. Rate of switching to the crf-FI first decreased and then increased as the extinction point approached, showing sensitivity to both prior choices and reinforcement contingencies. In a third experiment, crf-FI availability was limited to a brief window during the RI waiting time. When constrained in this way, switching occurred at a high rate regardless of when, during the RI waiting time, the crf-FI became available.  相似文献   
918.
To examine the effects of different types of goal setting on motor skill acquisition during advanced stages of learning. 44 female volleyball players were tested in four experimental training groups with generic goals, specific long-term goals, specific short-term goals, and as a control group. This study's pretest, training, and retention test phases used performance of a volleyball dig/forearm pass oriented to a target. Analyses yielded no significant differences among groups, although performance increased from pre- to retention test.  相似文献   
919.
The conflict-control loop theory proposes that the detection of conflict in information processing triggers an increase in cognitive control, resulting in improved performance on the subsequent trial. This theory seems consistent with the robust finding that conflict susceptibility is reduced following correct trials associated with high conflict: the conflict adaptation effect. However, despite providing favorable conditions for eliciting and detecting conflict-triggered performance adjustments, none of the five experiments reported here provide unequivocal evidence of such adjustments. Instead, the results corroborate and extend earlier findings by demonstrating that the conflict adaptation effect, at least in the flanker task, is only present for a specific subset of trial sequences that is characterized by a response repetition. This pattern of results provides strong evidence that the conflict adaptation effect reflects associative stimulus-response priming instead of conflict-driven adaptations in cognitive control.  相似文献   
920.
Bilateral deficit has been used to describe the phenomenon of a reduction in performance during synchronous bilateral movements when compared to the sum of identical unilateral movements. The study of bilateral deficit in humans under isometric, and to a lesser extent, dynamic conditions has shown bilateral decreases in force and muscle activation, and delayed reaction time. Results are equivocal, however, and biomechanical analyses of dynamic conditions, i.e., movements, are lacking. Our purpose was to determine, through an analysis of kinematic, kinetic, and electromyographic (EMG) data, whether or not bilateral deficit was present during a dynamic multi-joint movement under conditions where the external load was relatively equal for unilateral and bilateral efforts. Five male participants performed repeated unilateral and bilateral maximal horizontal leg press jumps under 100% (1BW) and 200% (2BW) relative body weight loads. Significant bilateral deficits in resultant ground reaction impulse of 27.7% and 13.0% were present in 1BW and 2BW, respectively. Maximum joint power at the hip exhibited significant deficits in both 1BW and 2BW of 35.6% and 25.1%, respectively. In both 1BW and 2BW conditions, ankle (15.5% and 11.5%), knee (10.9% and 5.7%), and hip (38.5% and 30.4%) work was significantly affected. Statistically significant EMG bilateral deficits were found in every muscle in both conditions except for rectus femoris during the 2BW trials. Bilateral deficit values ranged from 9.1% to 20.9% for 1BW, while deficits between 6.1% and 20.7% were found in 2BW. These results indicate that during dynamic leg press, bilateral deficit does exist, but that individual muscle activation levels and joint kinetics are not equally affected.  相似文献   
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