The effects of social influence on children's memory reports: the omission and commission error asymmetry

Children in two age groups (7 vs. 12 yrs, N= 174) individually interacted with a stranger and were later interviewed about this event. Right before the interview, each child encountered the stranger once again and he engaged in a conversation where he either suggested that a (central or peripheral) detail originally present in the event had actually not been there or that an originally non-present (central or peripheral) detail had in fact been there. It was hypothesized that the two types of misinformation would result in omission and commission errors respectively. The results showed that the social influence resulted in an asymmetric effect (i.e., more commission than omission errors). Importantly, we also found that the children made more errors with respect to the peripheral detail (a suitcase), compared to the central detail (a passenger). Younger children did not make more errors (neither omission nor commission errors) than older children.     

The effect of personality variables in the prediction of the execution of different prospective memory tasks in the laboratory

The study of prospective memory (ProM), the remembering of the delayed execution of intentions, has been growing in recent years, and we know quite a bit about the cognitive variables that affect it. But the performance of a task depends on personality variables as well as on cognitive ones, and the role of personality variables in ProM has only been partially studied, the results being less conclusive. We sought to address two main objectives: (1) to quantify the joint influence of cognitive and personality variables on three ProM tasks in the laboratory (two based on events and the other on time), and (2) to identify the personality profiles of those who perform well in these three ProM tasks as opposed to those who do not. The cognitive and personality variables were evaluated with two sessions of 157 participants. The 16 PF-5 was applied (Cattell, Cattell & Cattell, 1993) and other cognitive variables were measured. With the data obtained, we ran several regression analyses to determine how some cognitive variables (sustained attention, verbal fluency, interference, retrospective memory, selective attention) and personality factors (tested using the 16 PF-5) can help to explain the variance in the performance of prospective memory tasks. Our results show that the contribution of personality predictor variables is moderate and smaller than that of the cognitive variables for predicting the execution of ProM tasks in the laboratory. Furthermore the intervention of the personality variables differs depending on the ProM tasks used. Global self-control and rule-consciousness were the personality variables that contributed the most in the prediction of the scores in the ProM tasks that were used.     

An fMRI study of phonological and spatial working memory using identical stimuli

The aim of the present fMRI study was to localize brain areas that were uniquely activated for phonological versus spatial working memory. Previous studies have reported inconsistent results, most likely because of methodological heterogeneity varying both stimuli and instructions in the same study. Here, identical consonant-vowel-consonant non-words were visually presented to the subjects in a 2-back paradigm under two different instructions; the subjects either had to memorize the non-words per se or their location. The results give evidence for a hemispheric organization of working memory, with dominance for processing of phonological information in the left hemisphere and frontal cortex, and spatial information in the right hemisphere and parietal cortex. The results also reflect a certain overlap between the neuronal network for working memory and processing of verbal and spatial material. These findings are discussed with regard to processing specificity and the extent that activated areas also may reflect perceptual processes.     

Examination of the processing speed account in a population-based longitudinal study with narrow age cohort design

The processing speed account suggests that general slowing of mental processing speed results in an overall decline, especially age-related decline, in other cognitive domains. Support for the speed account comes mainly from cross-sectional studies with participants that vary in age (age-heterogeneous samples). This study investigated how well variations in processing speed predict change of episodic recall in a longitudinal framework and examined with the Narrow Age Cohort (NAC) design. Data were obtained from Betula, a population-based longitudinal study. Both 5-year (n= 490; Time 3 - Time 4) and 10-year follow-up results (n= 608; Time 1 - Time 3) were used. In both samples, which were subjected to prospective dementia screening, we found considerably weaker associations in longitudinal data compared to cross-sectional, and also weaker associations in age-homogeneous than in age-heterogeneous samples. The results provide little support for the speed account.     

Cognitive and linguistic skills in Swedish children with cochlear implants - measures of accuracy and latency as indicators of development

The purpose of the present study was to examine working memory (WM) capacity, lexical access and phonological skills in 19 children with cochlear implants (CI) (5;7-13;4 years of age) attending grades 0-2, 4, 5 and 6 and to compare their performance with 56 children with normal hearing. Their performance was also studied in relation to demographic factors. The findings indicate that children with CI had visuospatial WM capacities equivalent to the comparison group. They had lower performance levels on most of the other cognitive tests. Significant differences between the groups were not found in all grades and a number of children with CI performed within 1 SD of the mean of their respective grade-matched comparison group on most of the cognitive measures. The differences between the groups were particularly prominent in tasks of phonological WM. The results are discussed with respect to the effects of cochlear implants on cognitive development.     

The Effects of Incentives on Visual–Spatial Working Memory in Children with Attention-deficit/Hyperactivity Disorder

Working memory is one of several putative core neurocognitive processes in attention-deficit/hyperactivity disorder (ADHD). The present work seeks to determine whether visual–spatial working memory is sensitive to motivational incentives, a laboratory analogue of behavioral treatment. Participants were 21 children (ages 7–10) with a diagnosis of ADHD-combined type. Participants completed a computerized spatial span task designed to assess storage of visual–spatial information (forward span) and manipulation of the stored information (backward span). The spatial span task was completed twice on the same day, once with a performance-based incentive (trial-wise feedback and points redeemable for prizes) and once without incentives. Participants performed significantly better on the backward span when rewarded for correct responses, compared to the no incentive condition. However, incentives had no effect on performance during the forward span. These findings may suggest the use of motivational incentives improved manipulation, but not storage, of visual–spatial information among children with ADHD. Possible explanations for the differential incentive effects are discussed, including the possibility that incentives prevented a vigilance decrement as task difficulty and time on task increased.     

Nature and facts about natural and artifactual categories: Sex differences in the semantic priming paradigm

There is abundant evidence from behavioral and neurophysiological experiments for the distinction of natural versus artifactual categories and a gender-specific difference: women’s performances in cognitive tasks increase when natural categories are used, whereas men’s performances increase with artifactual categories. Here, we used the semantic priming paradigm to study retrieval processes by presenting category labels as primes and exemplars as targets. Overall, in two experiments we found larger priming effects for natural than for artifactual categories. In addition, females showed positive priming effects for natural but negative effects for artifactual categories, whereas males showed positive priming effects for both categories. This pattern matches with that from other tasks and can be interpreted as evidence that the findings from these other tasks are, at least partially, indeed due to different representations or processing modes for males and females and not (exclusively) due to—for example—different familiarity with a category. In a further experiment, we showed that the found pattern for females can be manipulated by focusing on perceptual vs. functional features. The results can be interpreted as first evidence that there are (eventually in addition to different “crystallized” semantic structures) specific default processing modes that differ for males and females.     

视觉工作记忆中的加工与存储机制:回顾与思考

在视觉工作记忆的研究中,是否可能划分出视觉空间工作记忆和视觉物体工作记忆两个子系统还没有定论.子系统划分成立的基本前提是以特征为存储单位.当前关于存储单位的理论有特征理论、客体理论和双重存储等不同观点,多数视觉信息加工与存储机制的研究支持双重存储说.注意与视觉信息的加工和存储相互影响,因此,加工及存储机制的研究就要在具体的注意水平上进行.     

关键字母法对英文词汇记忆效能的制约因素初步研究

通过干预范式和中介刺激法,选择89名初中一年级学生为被试,采用一系列自编的材料和工具,初步探讨了关键字母法对英文词汇记忆效能的制约因素.结果表明:(1)无论从短期看,还是从长期看.难以识别关键字母,会在一定程度上制约关键字母法的效能,不过,该因素的制约作用并不显著;(2)无论从短期看.还是从长期看,无论为准确的回忆,还是为大致的回忆,难以提取关键字母释义是制约关键字母法的显著因素.中介刺激法,作为本研究的突出特征,试图继承和发展维果茨基所创立的双莺刺激法.     

A comparison of backward and forward spatial spans

The standard Corsi blocks task is frequently used to measure the capacity of visuospatial working memory, but the implications of the use of both forward and backward recall are still unclear. In the present study, we showed that the backward Corsi task is particularly powerful in discriminating between low- and high-spatial-ability individuals and involves different processes from those involved in the forward task. From a sample of 425 participants we selected one group of 20 high-spatial-ability participants and one of 20 low-spatial-ability participants. The results demonstrated that a backward spatial span offers specific information not available from a forward spatial span, and that there was no facilitation due to a descending format. In particular, in the low-spatial-ability group, performance was generally poorer, but backward Corsi recall was lower than forward recall, and participants did not show any advantage following the descending presentation format—which in some contexts is considered to reduce proactive interference. We conclude that the backward Corsi task has specific value and that the assumption of fully parallel verbal and visuospatial working-memory systems can lead to a variety of misunderstandings.