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171.
Emerging evidence suggests that nicotine may enhance short‐term memory. Some of this evidence comes from nonhuman primate research using a procedure called delayed matching‐to‐sample, wherein the monkey is trained to select a comparison stimulus that matches some physical property of a previously presented sample stimulus. Delays between sample stimulus offset and comparison stimuli onset are manipulated and accuracy is measured. The present research attempted to systematically replicate these enhancement effects with pigeons. In addition, the effects of nicotine were assessed under another, more dynamic, memory task called titrating‐delay matching‐to‐sample. In this procedure, the delay between sample offset and comparison onset adjusts as a function of the subject's performance. Correct matches increase the delay, mismatches decrease the delay, and titrated delay values serve as the primary dependent measure. Both studies examined nicotine's effects under acute and chronic administration. Neither provided clear or compelling evidence of memory enhancement following nicotine administration despite reliable and systematic dose‐related changes in response latency measures. A modest dose‐related effect on accuracy was found, but the magnitude of the effect appears to be directly related to tactics of data analysis involving best‐dose analyses of a very circumscribed subset of trial types.  相似文献   
172.
Domestic hens responded under multiple fixed‐ratio fixed‐ratio schedules with equal fixed ratios. One component provided immediate reinforcement and the other provided reinforcement after a delay, signaled by the offset of the key light. The components were presented quasirandomly so that all four possible transitions occurred in each session. The delay was varied over 0, 4, 8, 16, and 32 s with fixed‐ratio 5 schedules, and over 0, 8 and 32 s with fixed‐ratio 1, 15 and 40 schedules. Main effects of fixed‐ratio value and delay duration were detected on between‐ratio pauses. Pauses were longer when the multiple‐schedule stimulus correlated with a delayed‐reinforcer component was presented, with the longest pauses occurring at the transition from a component with an immediate reinforcer to one with a delayed reinforcer. Pause durations were shortest during immediate components. Overall, both the presence or absence of a delay in the upcoming component, and the presence or absence of a delay in the preceding component affected pause length, but the upcoming delay had the larger effect. Thus changes in delay had similar effects to past reports of the effects of changes in response force, response requirement, and reinforcer magnitude in multiple fixed‐ratio fixed‐ratio schedules.  相似文献   
173.
Havik, M., Jakobson, A., Tamm, M., Paaver, M., Konstabel, K., Uusberg, A., Allik, J., Ööpik, V. & Kreegipuu, K. (2012). Links between self‐reported and laboratory behavioral impulsivity. Scandinavian Journal of Psychology 53, 216–223. A major problem in the research considering impulsivity is the lack of mutual understanding on how to measure and define impulsivity. Our study examined the relationship between self‐reported impulsivity, behavioral excitatory and inhibitory processes and time perception. Impulsivity – fast, premature, thoughtless or disinhibited behavior – was assessed in 58 normal, healthy participants (30 men, mean age 21.9 years). Self‐reported impulsivity as measured by Adaptive and Maladaptive Impulsivity Scale (AMIS) and behavioral excitatory and inhibitory processes as measured by Stop Signal Task were not directly related. Time perception, measured by the retrospective Time Estimation Task, was related to both. The length of the perceived time interval was positively correlated to AMIS Disinhibition subscale and negatively to several Stop Signal Task parameters. The longer subjects perceived the duration to last, the higher was their score on Disinhibition scale and the faster were their reactive responses in the Stop Signal Task. In summary our findings support the idea of cognitive tempo as a possible mechanism underlying impulsive behavior.  相似文献   
174.
Since knowledge intensive work often requires self-management, one might fear that persons who are dependent on work success for self-esteem will have difficulties in finding a healthful and sustainable balance between internal needs and external demands. Accordingly, we examined to what degree work-related performance-based self-esteem (PBS) was linked to work and health behaviors in 392 knowledge workers (226 women, 166 men). In the women group, multiple binary logistic regression analyses with repeated measurements showed that the PBS score was associated with 10 of the 17 examined work and health behaviors. For men the corresponding figure was 3 of 17. In both men and women, higher PBS scores were positively associated with reports of efforts and strivings for work as well as attending work while ill. In conclusion, statistically significant relationships between PBS and work and health behaviors were more clearly visible among women than men. Whether this gender difference is dependent on the study design, or on true inherent differences between women and men, cannot be concluded with any certainty. However, persons who described themselves as being relatively more dependent on work accomplishments for a high self-esteem, as expressed by the PBS score, seem to display work behaviors that may lessen their restitution time. In addition, they also seem to be more prone to work while sick.  相似文献   
175.
Using a person-oriented approach the study examined whether bullying victimization at school continued into cyberspace victimization in a large sample of high school students in Lithuania (N = 1667, 58% girls), age 15-19 (M = 17.29, SD = 0.95). Three forms of traditional bullying (verbal, physical and relational) and seven forms of cyberbullying victimization through cell phones and computers were included in the analysis. The findings revealed that 35% of traditional bullying victims were also bullied in cyberspace. In particular, adolescents who experienced predominantly verbal and relational bullying at school, showed a higher risk of victimization in cyberspace a year later, while this was not observed for predominantly physical forms of traditional bullying. The findings point to the importance of a cross-contextual perspective in studies on stability of bullying victimization.  相似文献   
176.
Previous studies have noted that writing processes are impaired by task-irrelevant background sound. However, what makes sound distracting to writing processes has remained unaddressed. The experiment reported here investigated whether the semanticity of irrelevant speech contributes to disruption of writing processes beyond the acoustic properties of the sound. The participants wrote stories against a background of normal speech, spectrally-rotated speech (i.e., a meaningless sound with marked acoustic resemblance to speech) or silence. Normal speech impaired quantitative (e.g., number of characters produced) and qualitative/semantic (e.g., uncorrected typing errors, proposition generation) aspects of the written material, in comparison with the other two sound conditions, and it increased the duration of pauses between words. No difference was found between the silent and the rotated-speech condition. These results suggest that writing is susceptible to disruption from the semanticity of speech but not especially susceptible to disruption from the acoustic properties of speech.  相似文献   
177.
Competing models of attention make different predictions of how priming from recent stimulus processing could interact with intended selection. The present experiment examined the interaction between exogenous attention and endogenous priming across trial sequences. A sound cue directed attention to left, right or both sides before a dichotic syllable pair was presented. Participants were asked to report one syllable from each trial. Results showed that responses were slower on trials where one of the presented syllables had also been presented on the previous trial. Within these trials, the repeated syllable was selected less frequently, and the responses doing so were slower. Examined according to response choice on the preceding trial, syllables that had been ignored on the preceding trial tended to be ignored on the current trial (negative priming), while syllables that had been selected on the preceding trial tended to be selected on the current trial (positive priming). Responses that followed these selection biases were faster than responses that did not. Response selection was also influenced by the attention direction cue for the current trial, but not by the cue presented on the preceding trial. The results support an attentional model where traces from the preceding processing are retained, and current selection is biased to minimize cognitive conflict between recent and current processing. Negative priming appears to be due to after-effects of preceding processing, independently of the intentions behind that processing. The study accounts for positive and negative priming of dichotic listening sequences within an established, computationally viable biased competition framework.  相似文献   
178.
Larsson Sundqvist, M., Todorov, I., Kubik, V. & Jönsson, F.U. (2012) Study for now, but judge for later: Delayed judgments of learning promote long‐term retention. Scandinavian Journal of Psychology 53, 450–454. Delayed judgments of learning (JOL) are assumed to be based on covert retrieval attempts. A common finding is that testing memory during learning improves later retention (i.e., the testing effect), and even more so than an equivalent amount of study, but only after a longer retention interval. To test the assertion that also delayed JOLs improve memory, the participants either studied Swahili‐Swedish word pairs four times, or they both studied (two times) and performed delayed JOLs (two times) alternately. Final cued recall test were given after either five minutes or one week. Results showed a reliable learning‐group by retention‐interval interaction, with less forgetting in the group that alternated between studying and making JOLs. The results are discussed in relation to the self‐fulfilling prophecy account of Spellman and Bjork (1992) , and in terms of study advice, the results further underscore the importance of delaying JOLs when studying and evaluating one’s ongoing learning.  相似文献   
179.
Moksnes, U. K. & Espnes, G. A. (2012). Self‐esteem and emotional health in adolescents – gender and age as a potential moderators. Scandinavian Journal of Psychology 53, 483–489. The present paper investigates possible gender and age differences on emotional states (depression and anxiety) and self‐esteem as well as the association between self‐esteem and emotional states. The cross‐sectional sectional sample consists of 1,209 adolescents 13–18 years from public elementary and secondary schools in mid‐Norway. The results showed that girls reported higher scores on state anxiety and state depression, whereas boys consistently scored higher on self‐esteem in all age groups. Self‐esteem was strongly and inversely associated with both state depression and state anxiety. An interaction effect of gender by self‐esteem was found on state depression, where the association was stronger for girls than for boys. The associations found give support for the positive role of self‐esteem in relation to adolescents’ emotional health and well‐being.  相似文献   
180.
Refugees have often been exposed to multiple traumas making them prone to mental health problems later. The aim of this study is to describe the prevalence and symptom load of psychiatric disorders in refugees admitted to psychiatric outpatient clinics and to investigate the relationship between multiple exposure to traumatic events, the severity of traumatic symptoms and post-migration stressors. A clinical sample of 61 refugee outpatients from psychiatric clinics in Southern Norway was cross-sectionally examined using three structured clinical interviews (SCID-PTSD, SIDES and MINI) and self-report psychometric instruments (HSCL-25, IES-R). Post-traumatic Stress Disorder (PTSD) was diagnosed in 82% of the patients, while Disorders of Extreme Stress Not Otherwise Specified (DESNOS) was present in 16% of them. Comorbidity was considerable; 64% of the patients had both PTSD and major depression disorder (MDD) and 80% of those who had PTSD had three or more additional diagnoses. Multi-traumatized refugees in outpatient clinics have high prevalence of PTSD, DESNOS, comorbid depression and anxiety disorders. A more severe symptomatology was found in patients diagnosed with both PTSD and DESNOS, than in those diagnosed with only PTSD. Higher rates of unemployment, weak social network and weak social integration were also prevalent in these outpatients, and related to increased psychiatric comorbidity and severity of symptoms. Further research may clarify the existence of a cumulative relationship between pre-resettlement traumas and post-resettlement stressors in the mental health of refugees, which in turn may help to improve therapeutic interventions.  相似文献   
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