语文学习困难儿童的短时记忆、工作记忆和加工速度

短时记忆、工作记忆和加工速度反映了不同的认知加工.采用多因素混合实验设计,在严格控制条件下,比较了语文学习困难和控制组儿童的工作记忆、短时记忆和加工速度的差异.结果发现,与控制组相比,语文学习困难儿童在工作记忆、短时记忆和加工速度方面均存在明显的不足,但短时记忆和加工速度不能解释不同能力组之间的差异,语文学习困难儿童的缺陷在于工作记忆能力的下降.工作记忆的缺陷在于言语工作记忆的不足,与视空间工作记忆能力无关,语文学习困难与特定的工作记忆(言语工作记忆)能力的不足有关.工作记忆缺陷的原因在于存储能力的不足,而不是加工效率的缺陷造成的.     

Non-ruminative processing reduces overgeneral autobiographical memory retrieval in students

It has been suggested that overgeneral memory (OGM) represents a vulnerability marker for depression [Williams, J. M. G., Barnhofer, T., Crane, C., Hermans, D., Raes, F., Watkins, E., et al. (2007). Autobiographical memory specificity and emotional disorder. Psychological Bulletin, 133, 122-148]. One important underlying mechanism involved is rumination [e.g., Watkins, E., & Teasdale, J. D. (2001). Rumination and overgeneral memory in depression: Effects of self-focus and analytic thinking. Journal of Abnormal Psychology, 110, 353-357; Watkins, E., & Teasdale, J. D. (2004). Adaptive and maladaptive self-focus in depression. Journal of Affective Disorders, 82, 1-8]. It is as yet unclear to what extent the relationship between rumination and OGM also applies to nonclinical groups. The present study investigated this relationship in a nonclinical student sample, using an innovative sentence completion procedure to assess OGM. As hypothesized, the experimental induction of a concrete, process-focused (or non-ruminative) thinking style (n=102) led to less OGMs as compared to the experimental induction of an abstract, evaluative (or ruminative) thinking style (n=93). The present results add to the accumulating body of evidence that abstract, evaluative (or ruminative) thinking is a crucial underlying process of OGM, and expand prior literature by extending this idea to nonclinical individuals and by using a new procedure to assess OGM.     

The SNARC effect in the processing of second-language number words: Further evidence for strong lexico-semantic connections

We present new evidence that word translation involves semantic mediation. It has been shown that participants react faster to small numbers with their left hand and to large numbers with their right hand. This SNARC (spatial-numerical association of response codes) effect is due to the fact that in Western cultures the semantic number line is oriented from left (small) to right (large). We obtained a SNARC effect when participants had to indicate the parity of second-language (L2) number words, but not when they had to indicate whether L2 number words contained a particular sound. Crucially, the SNARC effect was also obtained in a translation verification task, indicating that this task involved the activation of number magnitude.     

Timing is everything: Changes in presentation rate have opposite effects on auditory and visual implicit statistical learning

Implicit statistical learning (ISL) is exclusive to neither a particular sensory modality nor a single domain of processing. Even so, differences in perceptual processing may substantially affect learning across modalities. In three experiments, statistically equivalent auditory and visual familiarizations were presented under different timing conditions that either facilitated or disrupted temporal processing (fast or slow presentation rates). We find an interaction of rate and modality of presentation: At fast rates, auditory ISL was superior to visual. However, at slow presentation rates, the opposite pattern of results was found: Visual ISL was superior to auditory. Thus, we find that changes to presentation rate differentially affect ISL across sensory modalities. Additional experiments confirmed that this modality-specific effect was not due to cross-modal interference or attentional manipulations. These findings suggest that ISL is rooted in modality-specific, perceptually based processes.     

The role of visual spatial attention in adult developmental dyslexia

The present study investigated the nature of visual spatial attention deficits in adults with developmental dyslexia, using a partial report task with five-letter, digit, and symbol strings. Participants responded by a manual key press to one of nine alternatives, which included other characters in the string, allowing an assessment of position errors as well as intrusion errors. The results showed that the dyslexic adults performed significantly worse than age-matched controls with letter and digit strings but not with symbol strings. Both groups produced W-shaped serial position functions with letter and digit strings. The dyslexics' deficits with letter string stimuli were limited to position errors, specifically at the string-interior positions 2 and 4. These errors correlated with letter transposition reading errors (e.g., reading slat as “salt”), but not with the Rapid Automatized Naming (RAN) task. Overall, these results suggest that the dyslexic adults have a visual spatial attention deficit; however, the deficit does not reflect a reduced span in visual–spatial attention, but a deficit in processing a string of letters in parallel, probably due to difficulty in the coding of letter position.     

Specifying the human body configuration

Three experiments investigated the specific spatial relations that define the human body configuration. In Experiment 1, participants searched for scrambled bodies amongst normal distractors. In Experiments 2 and 3 participants were asked to identify whether single body images (upright or inverted) were scrambled or normal. Scrambled bodies had head or limbs displaced to either symmetrical or asymmetrical positions. Experiment 1 showed that asymmetrical violations are recognized faster than symmetrical violations. All three experiments revealed that when the number of structural violations is held constant, head violations are recognized faster than limb violations. Experiment 3 also showed a greater inversion effect for scrambled bodies that maintained head on top and vertical symmetry, providing evidence that these are key spatial relations in the human body configuration. Overall, the results supported our hypothesis that the human body configuration is defined primarily by a head at the apex of a vertically symmetrical body.     

Extrafoveal Processing in Categorical Search for Geometric Shapes: General Tendencies and Individual Variations

The paper addresses the capabilities and limitations of extrafoveal processing during a categorical visual search. Previous research has established that a target could be identified from the very first or without any saccade, suggesting that extrafoveal perception is necessarily involved. However, the limits in complexity defining the processed information are still not clear. We performed four experiments with a gradual increase of stimuli complexity to determine the role of extrafoveal processing in searching for the categorically defined geometric shape. The series of experiments demonstrated a significant role of extrafoveal processing while searching for simple two-dimensional shapes and its gradual decrease in a condition with more complicated three-dimensional shapes. The factors of objects’ spatial orientation and distractor homogeneity significantly influenced both reaction time and the number of saccades required to identify a categorically defined target. An analysis of the individual p-value distributions revealed pronounced individual differences in using extrafoveal analysis and allowed examination of the performance of each particular participant. The condition with the forced prohibition of eye movements enabled us to investigate the efficacy of covert attention in the condition with complicated shapes. Our results indicate that both foveal and extrafoveal processing are simultaneously involved during a categorical search, and the specificity of their interaction is determined by the spatial orientation of objects, type of distractors, the prohibition to use overt attention, and individual characteristics of the participants.     

Features of the Expert-System-Shell SPIRIT

The inference process in a probabilistic and conditional environmentunder minimum relative entropy, permits the acquisition of basicknowledge, the consideration of - even uncertain - ad hoc knowledge,and the response to queries. Even if these procedures are wellknown in the relevant literature their realisation for large-scaleapplications needs a sophisticated tool, allowing the communicationwith the user as well as all relevant logical transformationsand numerical calculations. SPIRIT is an Expert-System-Shellfor these purposes. Even for hundreds of – consistent– facts about the involved variables’ dependenciesthe shell automatically generates the corresponding epistemicstate, thus permitting the derivation of conclusions from theacquired knowledge. These conclusions’ reliability orprecision can be checked, inviting the user to enrich the knowledgeby further facts, if desired. Any inconsistencies among providedfacts are detected, and their elimination will be supportedby the shell. Knowledge acquisition can come from provided factsby a knowledge engineer as well as from real world data; inductivelearning supports the use of such data. An important capabilityof the shell is the calculation of impacts upon ideas or conceptsfrom a given stimulus. This paper is a brief survey of theoreticalconcepts and the corresponding features of the system, whichare accompanied by illustrative examples.     

Searching for the Trace: The Influence of Age, Lexical Activation and Working Memory on Sentence Processing

To investigate the stability of trace reactivation in healthy older adults, 22 older volunteers with no significant neurological history participated in a cross-modal priming task. Whilst both object relative center embedded (ORC) and object relative right branching (ORR) sentences were employed, working memory load was reduced by limiting the number of words separating the antecedent from the gap for both sentence types. Analysis of the results did not reveal any significant trace reactivation for the ORC or ORR sentences. The results did reveal, however, a positive correlation between age and semantic priming at the pre-gap position and a negative correlation between age and semantic priming at the gap position for ORC sentences. In contrast, there was no correlation between age and priming effects for the ORR sentences. These results indicated that trace reactivation may be sensitive to a variety of age related factors, including lexical activation and working memory. The implications of these results for sentence processing in the older population are discussed.