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981.
Although, in everyday life, patients with attention deficit hyperactivity disorder (ADHD) are frequently distracted by goal-irrelevant affective stimuli, little is known about the neural and behavioral substrates underlying this emotional distractibility. Because some of the most important brain responses associated with the sudden onset of an emotional distracter are characterized by their early latency onset and short duration, we addressed this issue by using a temporally agile neural signal capable of detecting and distinguishing them. Specifically, scalp event-related potentials (ERPs) were recorded while 20 boys with ADHD combined type and 20 healthy comparison subjects performed a digit categorization task during the presentation of three types of irrelevant, distracting stimuli: arousing negative (A−), neutral (N) and arousing positive (A+). Behavioral data showed that emotional distracters (both A− and A+) were associated with longer reaction times than neutral ones in the ADHD group, whereas no differences were found in the control group. ERP data revealed that, compared with control subjects, boys with ADHD showed larger anterior N2 amplitudes for emotional than for neutral distracters. Furthermore, regression analyses between ERP data and subjects’ emotional ratings of distracting stimuli showed that only in the ADHD group, emotional arousal (ranging from calming to arousing) was associated with anterior N2: its amplitude increased as the arousal content of the visual distracter increased. These results suggest that boys with ADHD are more vulnerable to the distracting effects of irrelevant emotional stimuli than control subjects. The present study provides first data on the neural substrates underlying emotional distractibility in ADHD.  相似文献   
982.
Both children with epilepsy and children with ADHD may be characterized by slowing on reaction-time measurement. This is of particular interest, as neuropsychological assessment is often requested in the differential diagnosis between children with short non-convulsive epileptic seizures and children with ADHD. In this study we attempt to identify patterns of impairment on timed tasks that are specific for epilepsy, relative to ADHD. This study was an open, controlled parallel-group clinical investigation which included two groups of patients: 60 children with ADHD and 60 children with epilepsy. These children were compared with a control group (n =30) on two types of timed cognitive tasks: tasks with low information load (simple reaction-time measurement) and tasks with high information load (multiple decision reaction-time measurement). The simple reaction-time measurements show significant differences between ADHD and controls (all except for visual RT non-dominant hand) and between epilepsy and controls (only one test). No significant differences were found between epilepsy and ADHD. The two tests with high information load show significant slowing compared with the controls for epilepsy on the Binary Choice Reaction-Time Test and for ADHD on the Visual Searching Test. On both tests also the differences between epilepsy and ADHD are significant. The two tests in combination have a relatively satisfactory potential to classify the children with ADHD (75% correct classification) and the children with epilepsy (55% correct classification). We may conclude that complex reaction-time tests (i.e., timed tasks with high information load) have potential for assessing the differential impact of ADHD and epilepsy on attentional function. These tasks specifically reveal general slowing for children with epilepsy and slowing as an effect of failures of inhibitory self control on unstructured tasks for ADHD.  相似文献   
983.
Consulting Heidegger's other texts composed during 1936–1942, this article employs a principle of charity and constructs a consistent discourse about an inceptual negativity Heidegger articulates through a confrontation with Hegel in GA 68. Heidegger deliberately differentiates his use of denial (Verneinung) that bears Being-historical significance from Hegel's Negation that allegedly aims at synthesis or elevation as a dialectical movement. Being unsatisfied with his approach that remains entangled with metaphysics in the Contributions, Heidegger attempts to transform the question of the Nothing from a subsidiary question to Beyng to an abyssal question. One needs to go under toward the Nothing in its concealed, conjoined, and most intimate relation to Beyng. The movement of going under is fundamentally significant for transitions that could occur from out of the history of Beyng. Never being the fullness of essence, the Nothing places a limit on Beyng, constantly thwarts its unfolding, and maintains it in finitude.  相似文献   
984.
It has previously been shown that task performance and frontal cortical activation increase after cognitive conflict. This has been argued to support a model of attention where the level of conflict automatically adjusts the amount of cognitive control applied. Conceivably, conflict could also modulate lower-level processing pathways, which would be evident as trial-to-trial changes in domain specific activation. The present fMRI experiment used a syllable identification task where conflict is manipulated by presenting recently ignored syllables. Results showed that on trials following a high conflict trial, activation increased primarily in the planum temporale region of the left temporal cortex, an area believed to be involved in syllable discrimination. The experiment thus showed a transient, domain specific attention effect that was modulated on a trial-to-trial basis. We argue that this indicates a self-regulating system where increased levels of conflict directs resources in order to improve performance.  相似文献   
985.
There is growing evidence that among the different conduct disorder (CD) behaviors, physical aggression, but not theft, links to low neurocognitive abilities. Specifically, physical aggression has consistently been found to be negatively related to neurocognitive abilities, whereas theft has been shown to be either positively or not related to neurocognition. The specificity of these links needs further examination because attention deficit hyperactivity disorder (ADHD) links to both physical aggression and neurocognitive variation. The development of self-reported physical aggression and theft, from age 11 to 17 years, was studied in a prospective at-risk male cohort via a dual process latent growth curve model. Seven neurocognitive tests at age 20 were regressed on the growth parameters of physical aggression and theft. The links between neurocognition and the growth parameters of physical aggression and theft were adjusted for ADHD symptoms at ages 11 and 15 (parent, child and teacher reports). Results indicated that verbal abilities were negatively related to physical aggression while they were positively associated with theft. However, inductive reasoning was negatively associated with increases in theft across adolescence. Symptoms of ADHD accounted for part of the neurocognitive test links with physical aggression but did not account for the associations with theft. These differences emphasize the importance of examining specific CD behaviors to better understand their neurodevelopmental mechanisms. They also suggest that youth who engage in different levels of physical aggression or theft behaviors may require different preventive and corrective interventions.  相似文献   
986.
内隐联想测验“内隐性”的可控性研究   总被引:1,自引:0,他引:1       下载免费PDF全文
贾凤芹  冯成志 《心理科学》2012,35(4):799-805
在许多社会科学研究中,社会称许性会对研究的效度产生不良影响。研究者希望能得到被试的真实态度和反应,从而极力避免这种社会称许性偏见。内隐测量工具的一个主要目的是让研究者能够获得未加任何粉饰的态度测量结果从而消除和避免自我表现和社会称许性。本文通过四个实验考察了内隐联想测验的可掩饰性、掩饰的持久性、掩饰的条件化和IAT经验的迁移性,结果显示:(1)被试可以通过一定的反应策略来掩饰其真实的内隐态度,从而使所测得的个体内隐态度和群体内隐态度失真,典型的反应策略是均衡相容和不相容任务的反应速度;(2)内隐联想测验的可掩饰性需以先前的IAT经验为基础,且IAT经验无需属于相同的测验范畴,对IAT原理的掌握将有助于被试成功地实施掩饰;(3)内隐联想测验的可掩饰性具有一定的时效性,先前的IAT经验越久远,则成功掩饰的可能性越低;总之,内隐联想测验并不能彻底避免社会称许性。  相似文献   
987.
A commutative BCK-algebra with the relative cancellation property is a commutative BCK-algebra (X;*,0) which satisfies the condition: if ax, ay and x * a = y * a, then x = y. Such BCK-algebras form a variety, and the category of these BCK-algebras is categorically equivalent to the category of Abelian ℓ-groups whose objects are pairs (G, G 0), where G is an Abelian ℓ-group, G 0 is a subset of the positive cone generating G + such that if u, vG 0, then 0 ∨ (u - v) ∈ G 0, and morphisms are ℓ-group homomorphisms h: (G, G 0) → (G′,G0) with f(G 0) ⫅ G0. Our methods in particular cases give known categorical equivalences of Cornish for conical BCK-algebras and of Mundici for bounded commutative BCK-algebras (= MV-algebras). This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
988.
As part of the behavioral treatment in the Multimodal Treatment Study of Children with ADHD (MTA), children participated in an intensive summer treatment program (STP). This study examined the differences between 57 children in the combined treatment (Comb) group, who were medicated, and 60 children in the behavioral treatment (Beh) group, who were unmedicated throughout the STP. Comb children were significantly better than Beh on 5 measures: rule following, good sportsmanship, peer negative nominations, and STP teacher posttreatment ratings of inattention/overactivity. Groups did not differ on any of the other 30 measures, and responded similarly to the STP over time. Comparisons to normative data revealed that Comb children were more likely to fall within the normative range on 6 measures. The differences between these results and the main MTA results, in which Comb was always superior to Beh, are discussed in terms of the relative intensity of combined treatments. The implications for future studies of pharmacological and behavioral treatment for ADHD are discussed.  相似文献   
989.
Studies examining interventions for adolescents diagnosed with attention-deficit/hyperactivity disorder (ADHD) were reviewed to evaluate their efficacy. These efficacy findings were supplemented with a preliminary system for judging safety and practicality. Results suggest that the stimulant drug methylphenidate (MPH) is safe and well-established empirically, but has some problems with inconvenience and noncompliance. Preliminary research supports the efficacy, safety, and practicality of some psychotherapeutic interventions, including behavioral classroom interventions, note-taking training, and family therapy. Treatment with tricyclic antidepressants was judged to have minimal empirical support and debatable safety. Very little is known about long-term effectiveness of treatments, long-term compliance, or multimodal treatments for adolescents such as stimulants plus behavior therapy.  相似文献   
990.
The increased risk of falls in the older aged population demands the development of assistive robotic devices capable of effective balance support. For the development and increased user acceptance of such devices, which provide balance support in a human-like way, it is important to understand the simultaneous occurrence of entrainment and sway reduction in human-human interaction. However, sway reduction has not been observed yet during a human touching an external, continuously moving reference, which rather increased human body sway. Therefore, we investigated in 15 healthy young adults (27.20±3.55 years, 6 females) how different simulated sway-responsive interaction partners with different coupling modes affect sway entrainment, sway reduction and relative interpersonal coordination, as well as how these human behaviours differ depending on the individual body schema accuracy. For this, participants were lightly touching a haptic device that either played back an average pre-recorded sway trajectory (“Playback”) or moved based on the sway trajectory simulated by a single-inverted pendulum model with either a positive (Attractor) or negative (Repulsor) coupling to participant's body sway. We found that body sway reduced not only during the Repulsor-interaction, but also during the Playback-interaction. These interactions also showed a relative interpersonal coordination tending more towards an anti-phase relationship, especially the Repulsor. Moreover, the Repulsor led to the strongest sway entrainment. Finally, a better body schema contributed to a reduced body sway in both the “reliable” Repulsor and the “less reliable” Attractor mode. Consequently, a relative interpersonal coordination tending more towards an anti-phase relationship and an accurate body schema are important to facilitate sway reduction.  相似文献   
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