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961.
Jonathan Buriticá Cristiano V. dos Santos 《Journal of the experimental analysis of behavior》2017,108(2):151-170
The concept of reinforcement value summarizes the effect of different variables, such as reinforcement delay, reinforcement magnitude, and deprivation level, on behavior. In the present set of experiments, we evaluated the effect of reinforcement devaluation on performance under FI schedules. The literature on timing and reinforcement value suggests that devaluation generates longer expected times to reinforcement than the same intervals trained under control conditions. We devalued reinforcement with delay in Experiments 1A, 1B, and 2, and diminished deprivation in Experiments 3A and 3B. Devaluation reduced response rates, increased the number of one‐response intervals, and lengthened postreinforcement pauses, but had inconsistent effects on other timing measures such as quarter life and breakpoint. The results of delayed reinforcement and diminished deprivation manipulations are well summarized as reinforcement devaluation effects. These results suggest that devaluation may reduce stimulus control. In addition, we argue that the process by which delayed reinforcement affects behavior might also explain some effects observed in other devaluation procedures through the concept of reinforcement value. 相似文献
962.
Carmen Moret‐Tatay Lenin‐Guillermo Lemus‐Zúñiga Diana Abad Tortosa Daniel Gamermann Andrea Vázquez‐martínez Esperanza Navarro‐Pardo J. Alberto Conejero 《Scandinavian journal of psychology》2017,58(4):304-311
The reaction time has been described as a measure of perception, decision making, and other cognitive processes. The aim of this work is to examine age‐related changes in executive functions in terms of demand load under varying presentation times. Two tasks were employed where a signal detection and a discrimination task were performed by young and older university students. Furthermore, a characterization of the response time distribution by an ex‐Gaussian fit was carried out. The results indicated that the older participants were slower than the younger ones in signal detection and discrimination. Moreover, the differences between both processes for the older participants were higher, and they also showed a higher distribution average except for the lower and higher presentation time. The results suggest a general slowdown in both tasks for age under different presentation times, except for the cases where presentation times were lower and higher. Moreover, if these parameters are understood to be a reflection of executive functions, these findings are consistent with the common view that age‐related cognitive deficits show a decline in this function. 相似文献
963.
Twenty-three offenders convicted of homicide or attempted murder/manslaughter, and their respective crimes, were examined to identify any common characteristics. Court documents were assessed, and the most prominent information of the offenders was that they were often single, most of them had no psychiatric diagnoses, the most frequent modus operandi was a knife or sharp weapon (although firearms resulted in more homicides), and the most common homicide typology was domestic disputes, and disputes between friends or acquaintances. Based on a cluster analysis, two profiles emerged: one with so-called traditional criminals and another profile over-represented with offenders who commit domestic crimes. 相似文献
964.
Karlen Lyons‐Ruth Jody Todd Manly Kai Von Klitzing Tuula Tamminen Robert Emde Hiram Fitzgerald Campbell Paul Miri Keren Astrid Berg Maree Foley Hisako Watanabe 《Infant mental health journal》2017,38(6):695-705
Children worldwide experience mental and emotional disorders. Mental disorders occurring among young children, especially infants (birth –3 years), often go unrecognized. Prevalence rates are difficult to determine because of lack of awareness and difficulty assessing and diagnosing young children. Existing data, however, suggest that rates of disorders in young children are comparable to those of older children and adolescents (von Klitzing, Dohnert, Kroll, & Grube, 2015 ). The lack of widespread recognition of disorders of infancy is particularly concerning due to the unique positioning of infancy as foundational in the developmental process. Both the brain and behavior are in vulnerable states of development across the first 3 years of life, with potential for enduring deviations to occur in response to early trauma and deprivation. Intervention approaches for young children require sensitivity to their developmental needs within their families. The primacy of infancy as a time of unique foundational risks for disorder, the impact of trauma and violence on young children's development, the impact of family disruption on children's attachment, and existing literature on prevalence rates of early disorders are discussed. Finally, global priorities for addressing these disorders of infancy are highlighted to support prevention and intervention actions that may alleviate suffering among our youngest world citizens. 相似文献
965.
It is well known that relative to neutral stimuli, attention is biased towards processing stimuli that convey threat. In a previous study in which a particular stimulus (e.g. a blue diamond) was associated with the delivery of an electrical shock, the presence of the fear-conditioned stimulus interfered with the execution of voluntary eye movements to other locations. Here, we show that this effect not only occurs early in time, but remains present long after the fear-conditioned stimulus was removed from the screen. In a subsequent experiment, we associated the presence of a particular stimulus with safety, that is, when this stimulus was present it was certain that no electrical shock would be delivered. The presence of the safety signalling stimulus also interfered with the execution of voluntary saccades, but only when the time between stimulus and cue presentation was relatively long. The results indicate that both signals of threat and signals of safety interfere with execution of a saccade long after the source of threat or safety has been removed. However, only threatening stimuli affect saccade execution early in time, suggesting that threatening stimuli drive selection exogenously. 相似文献
966.
Víctor M. Verdejo 《Philosophical Papers》2017,46(2):315-344
Ever since John Perry's developments in the late 70s, it is customary among philosophers to take de se contents as essentially tied to the explanation of action. The target explanation appeals to a subject-specific notion of de se content capable of capturing behavioural differences in central cases. But a subject-specific de se content leads us, I argue, to a subject-specific notion of intentional action that prevents basic forms of generalisation. Although this might be seen as a welcome revision of our pre-theoretical conceptions, I propose, instead, a strategy to circumvent this rather unexpected result: to reject subject-specific de se contents in favour of subject-specific ways of thinking that do not enter into the content of one's attitudes. 相似文献
967.
Maltreatment of children is a chronic community problem that increases the risk of future aggression. Despite several decades of research highlighting this relationship, few studies have explored the potential neuropsychological deficits that are likely to mediate it. This exploratory study aimed to examine how child maltreatment may be associated with aggression via impairment in the developing prefrontal-limbic-autonomic pathways that are implicated in neuropsychological models of aggression. Furthermore, it aimed to investigate the relationship between child maltreatment and both reactive and proactive aggression subtypes. To investigate this non-invasively in an at-risk population, children with a documented protective care history (n = 20) and a community control group (n = 30), aged between 6 and 12 years, were compared on measures of cardiovascular functioning, affect regulation and cognitive functioning aligned with this neuropsychological model. Whilst no group differences were found on cardiovascular functioning (i.e., resting heart rate, heart rate reactivity, heart rate variability), the protective care group performed significantly worse on measures of affect regulation and cognitive functioning (i.e., global intelligence, executive functioning, smell identification and social cognition). The relationship between child maltreatment and aggression was mediated by executive dysfunction and affect dysregulation but not global IQ, social cognition or olfactory identification. The results suggest that interventions targeting aggression in maltreated children will benefit from clinical assessment and psychological strategies that address the executive dysfunction and affect dysregulation that has been associated with this clinical outcome. 相似文献
968.
S. Chandra M. K. Samal N. N. Kumar V. M. Chavan S. Raghunathan 《Philosophical Magazine Letters》2017,97(12):504-514
The interaction between a brittle crack and pre-existing void in front of the crack tip was studied in the realm of molecular dynamics simulations at the nanoscale in face centred cubic Al within the framework of embedded-atom method. The results provide corroborative evidence of the fact that presence of a void in front of a running crack deters further crack growth. By performing an extensive series of simulations with different void sizes and crack-void distances coupled with statistical analysis, it has been found that (1) major role of voids is to decrease the fracture stress with increasing void size, in addition to slight increase in strain at which the crack growth occurs and the consequent strain to fracture, (2) fracture stress for a constant void size follows a sinusoidal distribution by varying the crack-void distance and (3) it is the void size that is most crucial in dictating the fracture properties of the material, rather than the void placement. 相似文献
969.
Alejandra E. Ruiz-Contreras Talía V. Román-López Ulises Caballero-Sánchez Cintia B. Rosas-Escobar E. Ivett Ortega-Mora Miguel A. Barrera-Tlapa 《Memory (Hove, England)》2017,25(3):335-343
Individual differences in working memory ability are mainly revealed when a demanding challenge is imposed. Here, we have associated cannabinoid 1 (CB1) receptor genetic variation rs2180619 (AA, AG, GG), which is located in a potential CNR1 regulatory sequence, with performance in working memory. Two-hundred and nine Mexican-mestizo healthy young participants (89 women, 120 men, mean age: 23.26 years, SD?=?2.85) were challenged to solve a medium (2-back) vs. a high (3-back) difficulty N-back tasks. All subjects responded as expected, performance was better with the medium than the high demand task version, but no differences were found among genotypes while performing each working memory (WM) task. However, the cost of the level of complexity in N-back paradigm was double for GG subjects than for AA subjects. It is noteworthy that an additive-dosage allele relation was found for G allele in terms of cost of level of complexity. These genetic variation results support that the endocannabinoid system, evaluated by rs2180619 polymorphism, is involved in WM ability in humans. 相似文献
970.
Bindi V. Shah 《Journal of Contemporary Religion》2017,32(2):299-314
The on-going importance of religion as a marker of identity among young South Asians has provoked reflection on the relationship between religion and citizenship in the aftermath of events such as 9/11 and 7/7. In general, European and American scholarship highlights different perspectives on the role of religion in the social incorporation of immigrants and their children. In this article I explore how religion shapes identity and citizenship among young Jains, a group that experiences successful socio-economic integration and material success in Britain and the United States. This qualitative comparative analysis of Jain institutions which are oriented towards young Jains reveals the ways in which the intersection of transnational circulation of religious ideas and actors, national integration regimes, migration histories, and the place of religion in specific contexts shapes religious identities, religious group boundaries, and religious discourses in different ways. Different Jain religious assemblages affirm views of religion in the United States as having a positive role in the social incorporation of immigrants and their children, but point to a more neutral role for religion in the incorporation of middle-class young Jains in Britain. 相似文献