无意识冲突的发生机制：基于Stroop范式的探讨

无意识信息对人们的行为有着十分重要的影响,它不仅能触发相对低级的认知功能而且也能触发冲突控制等相对高级的认知功能。尽管已有研究从行为和认知神经研究两个方面强有力地证实了无意识冲突的存在,但对无意识冲突是源自中枢加工产生的语义冲突还是晚期动作选择中产生的反应冲突存在激烈的争议。本研究采用分离语义冲突和反应冲突的实验逻辑在Stroop掩蔽启动任务中探讨了无意识冲突的机制。结果发现,无意识Stroop效应中既包含语义冲突又包含反应冲突。这说明无意识冲突可能由语义冲突和反应冲突共同构成。实验结果也进一步支持了无意识刺激可以加工到语义水平的观点。     

负相容效应中启动项-目标项关系对阈下信息加工的影响

采用掩蔽启动范式考察了负相容效应中启动项与目标项关系对阈下信息加工的影响,以及是否存在语义水平的负相容效应.两个实验分别以双箭头和汉字为掩蔽启动项,考察启动项和目标项重复、加工水平相同及加工水平不同三种条件下的启动效应.结果发现,两个实验的重复及加工水平相同条件下都出现负相容效应,且重复条件下启动量最大,加工水平不同条件下则无启动.这表明:(1)启动项与目标项的知觉重复影响启动量,但不是负相容效应的必要条件,只有当启动项和目标项加工水平相同时,才出现负相容效应;(2)存在语义水平上的负相容效应,阈下语义信息可得到加工并表现为对后继同类反应的抑制.     

Acceptance,well-being and goals in adolescents with chronic illness: a daily process analysis

Objective: The main aim of this study was to investigate the relationship between acceptance and well-being in adolescents with chronic illness from a daily process perspective. Furthermore, we explored the role of daily experienced interference and facilitation of life goals by treatment goals as mediating mechanisms.

Methods: Thirty-eight adolescents with cystic fibrosis (CF) or diabetes completed questionnaires assessing acceptance, negative life events and goal-related self-efficacy. Furthermore, an online diary assessing daily mood, daily experienced interference and facilitation of life goals by treatment goals was completed during three consecutive weeks.

Results: Acceptance of illness was positively related to daily well-being, but unrelated to daily goal interference and facilitation. Furthermore, daily goal interference and facilitation were unrelated to same-day and next-day well-being.

Conclusion: This study suggests that acceptance of illness plays an important role in the daily mood of adolescents with CF and diabetes. This relationship, however, was not mediated by daily experienced interference and facilitation of life goals by treatment goals. Further research is needed to determine whether interventions promoting acceptance are beneficial for adolescents with CF and diabetes.     

Limitations in Verbal Fluency Following Heavy Burdens of Early Childhood Diarrhea in Brazilian Shantytown Children

The effects of heavy burdens of diarrhea in the first 2 years of life on specific executive control function like verbal fluency are not well understood. In previous studies, we have shown associations of early childhood diarrhea (ECD) with nonverbal intelligence and school functioning. Therefore, we postulated that ECD might affect early neuropsychological development leading to long-term deficits in normal cognitive development. Based on our extensive 14-year prospective cohort studies of early childhood diarrheal illnesses in a Brazilian shantytown community, we examined ECD correlations between specific impairments of higher mental function and executive skills in shantytown children 5–10 years later (now at 6–12) years of age. Specifically we examined whether heavy diarrheal illnesses correlate with reduced performance on selected tests of executive function. Our study, for the first time, suggests a disproportional impairment in semantic but not phonetic fluency in a subset of children with heavy burdens of diarrhea in their first 2 years of life even when controlling for maternal education, breastfeeding, and child schooling. Similar semantic decrements have been associated with impaired recovery from brain injury. These exploratory studies suggest the importance of verbal fluency tests to assess executive functioning in children challenged by poor nutrition and diarrhea in early life. In addition, our unique findings show the potential influences of early childhood diarrhea on language development that is so critical to productive adulthood and potentially set a foundation for new neuropsychological approaches, which assess early burdens of enteric illnesses on childhood development.     

Epistemic Contextualism,Semantic Blindness and Content Unawareness

It is held by many philosophers that it is a consequence of epistemic contextualism that speakers are typically semantically blind, that is, typically unaware of the propositions semantically expressed by knowledge attributions. In his ‘Contextualism, Invariantism and Semantic Blindness’ (this journal, 2009), Martin Montminy argues that semantic blindness is widespread in language, and not restricted to knowledge attributions, so it should not be considered problematic. I will argue that Montminy might be right about this, but that contextualists still face a serious and related problem: that it is a consequence of epistemic contextualism that subjects are typically unaware of contents conveyed by knowledge attributions, independently of whether these are semantic or non-semantic contents. Even if semantic blindness is widespread in language, it does not seem that content unawareness of this sort is.     

Directed Forgetting of Related Words: Evidence for the Inefficient Inhibition Hypothesis

Fifth-grade children and college students were asked to remember some words and to forget others in an item-cued-directed-forgetting task. Taxonomically related pairs of words and control pairs that were unrelated in meaning were used as stimuli. Children found it more difficult than did adults to ignore forget-cued words that followed asso-ciatively related words that were remember-cued. The results provide support for D. F. Bjorklund and K. K. Harnishfeger's (1990) inefficient inhibition hypothesis (i.e., that the efficiency of inhibitory mechanisms improves as children develop). The results also suggest that the inhibition is occurring primarily in the early stages of processing.     

Challenge Point: A Framework for Conceptualizing the Effects of Various Practice Conditions in Motor Learning

The authors describe the effects of practice conditions in motor learning (e.g., contextual interference, knowledge of results) within the constraints of 2 experimental variables: skill level and task difficulty. They use a research framework to conceptualize the interaction of those variables on the basis of concepts from information theory and information processing. The fundamental idea is that motor tasks represent different challenges for performers of different abilities. The authors propose that learning is related to the information arising from performance, which should be optimized along functions relating the difficulty of the task to the skill level of the performer. Specific testable hypotheses arising from the framework are also described.     

Influence of practice schedules and attention on skill development and retention

Focus of attention during dual-tasks and practice schedules are important components of motor skill performance and learning; often studied in isolation. The current study required participants to complete a simple key-pressing task under a blocked or random practice schedule. To manipulate attention, participants reported their finger position (i.e., skill-focused attention) or the pitch of an auditory tone (i.e., extraneous attention) while performing two variations of a dual-task key-pressing task. Analyses were conducted at baseline, 10 min and 24 h after acquisition. The results revealed that participants in a blocked schedule, extraneous focus condition had significantly faster movement times during retention compared to a blocked schedule, skill focus condition. Furthermore, greatest improvements from baseline to immediate and delayed retention were evident for an extraneous attention compared to the skill-focused attention, regardless of practice schedule. A discussion of the unique benefits an extraneous focus of attention may have on the learning process during dual-task conditions is presented.     

语义整合的早期加工:来自ERPs的证据

本研究借助ERPs技术,通过操纵关键词与当前语境的语义合理性关系,考察在严格限定关键词词频变异性的情况下,语义整合过程能否反映在P2效应上。ERPs结果发现关键词呈现后,语义合理相比违背条件在右侧脑区诱发了更大的P2成分。该结果支持如果关键词低水平的变量信息(词频等)得到适当控制,ERPs技术可以检测到发生在250ms以前的语义整合过程。     

Deregulated semantic cognition contributes to object‐use deficits in Alzheimer's disease: A comparison with semantic aphasia and semantic dementia

Executive control is impaired from the early stages of Alzheimer's Disease (AD) and this produces deregulated semantic cognition (Corbett, Jefferies, Burns, & Lambon Ralph, 2012 ; Perry, Watson, & Hodges, 2000 ). While control deficits should affect semantic retrieval across all modalities, previous studies have typically focused on verbal semantic tasks. Even when non‐verbal semantic tasks have been used, these have typically employed simple picture‐matching tasks, which may be influenced by abnormalities in covert naming. Therefore, in the present study, we examined 10 patients with AD on a battery of object‐use tasks, in order to advance our understanding of the origins of non‐verbal semantic deficits in this population. The AD patients’ deficits were contrasted with previously published performance on the same tasks within two additional groups of patients, displaying either semantic degradation (semantic dementia) or deregulation of semantic retrieval (semantic aphasia; Corbett, Jefferies, Ehsan, & Lambon Ralph, 2009 ). While overall accuracy was comparable to the scores in both other groups, the AD patients’ object‐use impairment most closely resembled that observed in SA; they exhibited poorer performance on comprehension tasks that placed strong demands on executive control. A similar pattern was observed in the expressive domain: the AD and SA groups were relatively good at straightforward object use compared to executively demanding, mechanical puzzles. Error types also differed: while all patients omitted essential actions, the SA and AD groups’ demonstrations also featured unrelated intrusions. An association between AD patients’ object use and their scores on standard executive measures suggested that control deficits contributed to their non‐verbal semantic deficits. Moreover, in a task specifically designed to manipulate executive demand, patients with AD (and SA) exhibited difficulty in thinking flexibly about the non‐canonical uses of everyday objects, especially when distracted by semantically related objects. This study provides converging evidence for the notion that a failure of regulatory control contributes to multimodal semantic impairment in AD and uniquely demonstrates this pattern for the highly non‐verbal domain of object use.