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排序方式: 共有523条查询结果,搜索用时 15 毫秒
1.
A. W. Logue Henry Tobin John J. Chelonis Rex Y. Wang Nori Geary Stanley Schachter 《Psychopharmacology》1992,109(1-2):245-247
Cocaine abuse is often associated with behavior that takes into account short-term, but not long-term consequences. However, there has been no empirical research concerning the effects of cocaine on self-control (choice of a larger, more delayed reinforcer over a smaller, less delayed reinforcer). In the present research, when food-deprived rats repeatedly chose between a larger, more delayed food reinforcer and a smaller, less delayed food reinforcer, chronic intraperitoneal injections of 15 mg/kg cocaine (but not 10 mg/kg fluoxetine) decreased the rats' choices of the larger, more delayed reinforcer. Cocaine can decrease rats' self-control. 相似文献
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Because prepared learning has been defined in terms of response acquisition in spite of degraded input, it was expected that differences in resistance to extinction between skin conductance responses conditioned to potentially phobic and neutral stimuli would increase with increased interstimulus interval (ISI) and be larger with a trace than with a delay conditioning paradigm. Twelve groups with 10 subjects each were observed in a differential conditioning experiment manipulating ISI (2, 8, or 16 sec), paradigm (delay versus trace), and fear-relevance of the conditioned stimulus (potentially phobic versus neutral). The results showed highly reliable resistance to extinction of first-interval anticipatory responses to phobic stimuli, and no resistance to extinction of the corresponding responses to the neutral stimuli. This difference did not interact either with the ISI or the paradigm factor. Thus, although underscoring the reliability of the difference in conditioning to potentially phobic and neutral stimuli, the results did not support the specific hypothesis of conditioning to phobic stimuli as being less dependent on the ISI parameters than conditioning to neutral stimuli. 相似文献
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Tzelepi A Yang Q Kapoula Z 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2005,164(1):67-77
In this study, we investigated the effect of transcranial magnetic stimulation (TMS) over the right posterior parietal cortex (PPC) on the latency of two different types of visually-guided vertical saccades: reflexive saccades triggered by the sudden onset of a target, and saccades towards target locations known in advance. For this reason, we used two oculomotor tasks: a gap and a delay task, respectively. Nine normal subjects performed vertical saccades at ±7.5 and ±15°. TMS was applied at 80 and 100 ms after target onset in the gap task, and after fixation offset in the delay task. Without TMS, we confirmed a latency asymmetry in the gap task favouring upward saccades at the lower eccentricity (7.5°), and a latency symmetry in the delay task. TMS increased the latencies of all saccades in the delay task, when delivered at 100 ms. This effect was mostly pronounced for downward saccades at 7.5°. As a result, saccade latencies showed an asymmetry in this condition, similar to the one observed in the gap task without TMS. The gap task with TMS resulted in a variable latency distribution and no significant overall effect on saccade latency. Our results indicate that the right PPC is involved in the initiation of vertical saccades in the delay task, and that this involvement appears to be enhanced for downward saccades. A conclusion for the involvement of this area in the gap task could not be drawn from this study. 相似文献
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Federico E. Vaca Kaigang Li Selam Tewahade James C. Fell Denise L. Haynie Bruce G. Simons-Morton Eduardo Romano 《The Journal of adolescent health》2021,68(1):191-198
PurposeMore teens delay in driving licensure (DDL). It is conceivable they miss Graduated Driver Licensing (GDL) safety benefits. We assessed prevalence, disparities, and factors associated with DDL among emerging adults.MethodsData used were from all seven waves (W1–7) of the NEXT Generation Health Study (W1 in 10th grade [2009–2010]). The outcome variable was DDL (long-DDL [delayed >2 years], intermediate-DDL [delayed 1–2 years] versus no-DDL), defined as participants receiving driver licensure ≥1 year after initial eligibility. Independent variables included sex, urbanicity, race/ethnicity, family structure, parental education, family affluence, parental monitoring knowledge, parent perceived importance of alcohol nonuse, and social media use. Logistic regressions were conducted.ResultsOf 2,525 participants eligible for licensure, 887 (38.9%) reported intermediate-DDL and 1,078 (30.1%) long-DDL. Latinos (adjusted odds ratio [AOR] = 2.5 vs. whites) and those with lower affluence (AOR = 2.5 vs. high) had higher odds of intermediate-DDL. Latinos (AOR = 4.5 vs. whites), blacks (AOR = 2.3 vs. whites), those with single parent (AOR = 1.7 vs. both biological parents), whose parents’ education was high school or less (AOR = 3.7 vs. bachelor+) and some college (AOR = 2.0 vs. bachelor+) levels, and those with lower affluence (AOR = 4.4 vs. high) had higher odds of long-DDL. Higher mother’s monitoring knowledge (AOR = .6) was associated with lower odds of long-DDL, but not intermediate-DDL.ConclusionsSome teens that DDL “age out” of protections afforded to them by GDL driver restrictions. Minority race/ethnicity, socioeconomic status, urbanicity, and parenting factors contribute to DDL. Further study of these factors and their individual/collective contributions to DDL is needed to understand potential unintended consequences of GDL, particularly in more vulnerable youth. 相似文献
6.
Impulsivity and cigarette smoking: delay discounting in current, never, and ex-smokers 总被引:25,自引:10,他引:15
Rationale: Impulsivity is implicated in drug dependence. Recent studies show problems with alcohol and opioid dependence are associated
with rapid discounting of the value of delayed outcomes. Furthermore, discounting may be particularly steep for the drug of
dependence. Objectives: We determined if these findings could be extended to the behavior of cigarette smokers. In particular, we compared the discounting
of hypothetical monetary outcomes by current, never, and ex-smokers of cigarettes. We also examined discounting of delayed
hypothetical cigarettes by current smokers. Methods: Current cigarette smokers (n=23), never-smokers (n=22) and ex-smokers (n=21) indicated preference for immediate versus delayed money in a titration procedure that determined indifference points
at various delays. The titration procedure was repeated with cigarettes for smokers. The degree to which the delayed outcomes
were discounted was estimated with two non-linear decay models: an exponential model and a hyperbolic model. Results: Current smokers discounted the value of delayed money more than did the comparison groups. Never- and ex-smokers did not
differ in their discounting of money. For current smokers, delayed cigarettes lost subjective value more rapidly than delayed
money. The hyperbolic equation provided better fits to the data than did the exponential equation for 74 out of 89 comparisons.
Conclusions: Cigarette smoking, like other forms of drug dependence, is characterized by rapid loss of subjective value for delayed outcomes,
particularly for the drug of dependence. Never- and ex-smokers could discount similarly because cigarette smoking is associated
with a reversible increase in discounting or due to selection bias.
Received: 3 March 1999 / Final version: 11 May 1999 相似文献
7.
The disturbance caused by various short propagation delays to the perception of external sounds and own voice for a non-occluding hearing aid was investigated. Ten normal-hearing and 10 mildly hearing-impaired individuals listened to external sounds and their own voice while wearing non-occluding devices providing 10dB of linear gain. Participants rated the disturbance caused by delays of 2, 4 and 10ms to music, running speech, and their own voices. The results indicated greater disturbance for the longest delay for both subject groups when judging own voice, with the ratings of the hearing-impaired participants being lowest. Normal-hearing participants also judged the 10-ms delay as more disturbing for the external sounds. Owing to the listening conditions with constant gain from 800Hz and above, the results apply directly only to this experiment. Disturbance ratings for all delays were low, which suggests that any of those tested would be acceptable for this application. 相似文献
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