Computational principles of working memory in sentence comprehension

Understanding a sentence requires a working memory of the partial products of comprehension, so that linguistic relations between temporally distal parts of the sentence can be rapidly computed. We describe an emerging theoretical framework for this working memory system that incorporates several independently motivated principles of memory: a sharply limited attentional focus, rapid retrieval of item (but not order) information subject to interference from similar items, and activation decay (forgetting over time). A computational model embodying these principles provides an explanation of the functional capacities and severe limitations of human processing, as well as accounts of reading times. The broad implication is that the detailed nature of cross-linguistic sentence processing emerges from the interaction of general principles of human memory with the specialized task of language comprehension.     

The believability of children and their interviewers' hearsay testimony: when less is more

Hearsay testimony from children's interviewers is increasingly common in sexual abuse trials, but little is known about its effects on juries. In 2 studies, the authors examined college students' perceptions of 3 types of hearsay testimony (an actual interview with a child or an adult interviewer providing either the gist of what that child had said or a verbatim account of the interview). Interviewers were rated as more accurate and truthful than the children. The interview was rated as higher quality, and children's statements, including their false statements, were sometimes rated as more believable in the interviewer gist hearsay condition. Mock jurors reacted differently to various types of hearsay testimony, and interviewer gist testimony may favor a child's case.     

Teacher acquisition of functional analysis methodology

The current study examined methods for training teachers to use functional analysis methods. Teachers first received written and verbal instructions detailing attention and demand conditions. They then received training that included modeling, rehearsal, and performance feedback. Finally, probes were taken during ongoing class instruction. Results indicate that teachers acquired the skills and used them in classroom settings.     

Neuropsychological Sequelae of Subthalamic Nucleus Deep Brain Stimulation in Parkinson's Disease: A Critical Review

Neuropsychologists are increasingly involved in surgical candidacy evaluations and postoperative neurobehavioral assessments of patients with movement disorders, most notably those with disease (PD). We review here the initial studies regarding neuropsychological outcomes of deep brain stimulation (DBS) within the subthalamic nucleus (STN) for treatment of PD. Overall, these initial investigations provide preliminary support for the cognitive and neurobehavioral safety of STN DBS. Improvements in self-reported symptoms of depression and diminished verbal fluency were the most common findings, whereas changes in global cognitive abilities, memory, attention, and frontal/executive functions were inconsistent and most often described as nominal and/or transient. The generalizability of this literature is hindered by several methodological limitations, including small samples and the absence of appropriate control participants. The clinical and theoretical implications of these initial studies are highlighted and recommendations are offered to guide future research.     

Evidence of perspective-taking constraints in children's on-line reference resolution

Young children's communication has often been characterized as egocentric. Some researchers claim that the processing of language involves an initial stage that relies on egocentric heuristics, even in adults. Such an account, combined with general developmental difficulties with late-stage processes, could provide an explanation for much of children's egocentric communication. However, the experimental data reported in this article do not support such an account: In an elicited-production task, 5- to 6-year-old children were found to be sensitive to their partner's perspective. Moreover, in an on-line comprehension task, they showed sensitivity to common-ground information from the initial stages of language processing. We propose that mutual knowledge is not distinct from other knowledge relevant for language processing, and exerts early effects on processing in proportion to its salience and reliability.     

Neurocognitive insights into substance abuse

Cognitive studies are revealing key aspects of how drug abusers monitor and respond to negative feedback differently from non-abusers, and in doing so are adding an important piece to the conceptual puzzle that must be solved to understand, treat, and prevent drug abuse. In this review, we bring together two quite different lines of research, one addressing the selection of gambles in a risky decision task, and the other focused on imaging neural systems related to the detection and processing of errors. We suggest that diminished behavioural control, which is a cardinal feature of drug abuse, may be linked to alterations in the psychological and neural mechanisms that detect error signals and which, in turn, lead to optimization of behavioural responses.     

How many variables can humans process?

The conceptual complexity of problems was manipulated to probe the limits of human information processing capacity. Participants were asked to interpret graphically displayed statistical interactions. In such problems, all independent variables need to be considered together, so that decomposition into smaller subtasks is constrained, and thus the order of the interaction directly determines conceptual complexity. As the order of the interaction increases, the number of variables increases. Results showed a significant decline in accuracy and speed of solution from three-way to four-way interactions. Furthermore, performance on a five-way interaction was at chance level. These findings suggest that a structure defined on four variables is at the limit of human processing capacity.     

Psychological and stress hormone correlates in early life: a key to HPA-axis dysregulation and normalisation

Substantial recent research has focused on examining hormone indicators of psychosocial stress and on how relationships between stress and hormone changes might be linked to chronic illness. Particular attention has been paid to disease progression in cancer and HIV/AIDS. This focus has generated a plethora of research which has contributed both theoretically and clinically to the understanding of disease experience and the rate of disease progression. Measurement of salivary cortisol levels and diurnal variation has substantially advanced research methodology. Applying the unifying concept of allostasis and accumulated lifetime stress, this review attempts to assess the relevance of psychological and stress hormone correlates to disease resistance and health, through an examination of such correlates on the experience and outcomes of stress during childhood. Focus is on the role and importance of naturalistic social stress experiences such as school transition in healthy children, with emphasis on salivary cortisol as an endocrine marker of HPA-axis activation. It is argued that differing research perspectives offer valuable insight into the often assumed but largely unexplored links between early life experience and subsequent physical health outcomes in adulthood. Longitudinal studies incorporating measures of acute physical health outcome and of learning and memory are clearly needed.     

A psychometric comparison of the Beck Depression Inventory-II in English and Spanish

The Beck Depression Inventory-II (BDI-II; A. T. Beck, R. A. Steer, & G. K. Brown, 1996) is a widely used measure of depressive symptomatology originally authored in English and then translated to Spanish. However, there are very limited data available on the Spanish translation. This study compared the psychometric characteristics of the BDI-II in Spanish and English in a sample of 895 college students. The instrument was administered twice with a 1-week interval, either in the same language on both occasions or in a different language on each occasion. Results show strong internal consistency and good test-retest reliability in both languages. Confirmatory factor analysis demonstrated that the published English-language factor structure showed good fit with data from the Spanish instrument. Among bilingual participants who took the BDI-II in both languages, there was no significant language effect. These data provide initial evidence of comparable reliability and validity between the English and Spanish BDI-II in a nonclinical sample.