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Phonological Loop (phonological + loop)
Selected AbstractsNeural correlates of consolidation in working memoryHUMAN BRAIN MAPPING, Issue 3 2007Nelly Mainy Abstract Many of our daily activities rely on a brain system called working memory, which implements our ability to encode information for short-term maintenance, possible manipulation, and retrieval. A recent intracranial study of patients performing a paradigmatic working memory task revealed that the maintenance of information involves a distributed network of oscillations in the gamma band (>40 Hz). Using a similar task, we focused on the encoding stage and targeted a process referred to as short-term consolidation, which corresponds to the encoding of novel items in working memory. The paradigm was designed to manipulate the subjects' intention to encode: series of 10 letters were presented, among which only five had to be remembered, as indicated by visual cues preceding or following each letter. During this task we recorded the intracerebral EEG of nine epileptic patients implanted in mesiotemporal structures, perisylvian regions, and prefrontal areas and used time,frequency analysis to search for neural activities simultaneous with the encoding of the letters into working memory. We found such activities in the form of increases of gamma band activity in a set of regions associated with the phonological loop, including the Broca area and the auditory cortex, and in the prefrontal cortex, the pre- and postcentral gyri, the hippocampus, and the fusiform gyrus. Hum Brain Mapp, 2007. © 2006 Wiley-Liss, Inc. [source] Susceptibility of spatial and verbal working memory to demands of the central executive1JAPANESE PSYCHOLOGICAL RESEARCH, Issue 2 2004HIROHITO KONDO Abstract:, We used a dual-task paradigm to examine the degree to which domain-specific spatial and verbal subsystems depend on the domain-general central executive. Forty participants were asked to retain spatial or verbal information while performing a concurrent secondary task related to simple arithmetic. The secondary tasks consisted of three cognitive processes: single-digit addition, a digit-carrying operation, and digit reading. The single-digit addition and carry operation include central executive functioning, while digit reading relies solely on the phonological loop. The single-digit addition caused a performance decrement on the spatial working memory task, while the digit reading impaired performance on the verbal working memory task. The carry operation interfered with recall accuracy on both working memory tasks. The spatial working memory task was significantly correlated with the verbal working memory task only when the secondary task was more demanding on the central executive. Our results suggest that spatial working memory rather than verbal working memory is susceptible to failure of central executive functioning and that the central executive plays an important role in regulating the cognitive demands of different domains. [source] Working memory functioning in children with learning disabilities: does intelligence make a difference?JOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 1 2009C. Maehler Abstract Background Children with learning disabilities are identified by their severe learning problems and their deficient school achievement. On the other hand, children with sub-average school achievement and sub-average intellectual development are thought to suffer from a general intellectual delay rather than from specific learning disabilities. The open question is whether these two groups are characterised by differences in their cognitive functioning. The present study explored several functions of working memory. Method A working memory battery with tasks for the phonological loop, the visual,spatial sketchpad and central executive skills was presented in individual sessions to 27 children with learning disabilities and normal IQ (ICD-10: mixed disorders of scholastic skills), 27 children with learning disabilities and low IQ (intellectual disabilities), and a control group of 27 typically developing children with regular school achievement levels and normal IQ. Results The results reveal an overall deficit in working memory of the two groups with learning disabilities compared with the control group. However, unexpectedly, there were no differences between the two groups of children with disabilities (normal vs. low IQ). Conclusions These findings do not support the notion of different cognitive functioning because of differences in intelligence of these two groups. In the ongoing discussion about the role of intelligence (especially as to the postulated discrepancy between intelligence and school achievement in diagnosis and special education), our findings might lead to rethinking the current practice of treating these two groups as fundamentally different. [source] Working memory and Down syndromeJOURNAL OF INTELLECTUAL DISABILITY RESEARCH, Issue 12 2007A. Baddeley Abstract A brief account is given of the evolution of the concept of working memory from a unitary store into a multicomponent system. Four components are distinguished, the phonological loop which is responsible for maintaining speech-based information, the visuospatial sketchpad performing a similar function for visual information, the central executive which acts as an attentional control system, and finally a new component, the episodic buffer. The buffer comprises a temporary multidimensional store which is assumed to form an interface between the various subsystems of working memory, long-term memory, and perception. The operation of the model is then illustrated through an account of a research programme concerned with the analysis of working memory in Down syndrome. [source] Visuospatial memory and phonological loop in learning from multimediaAPPLIED COGNITIVE PSYCHOLOGY, Issue 6 2002Valérie Gyselinck The dual-task paradigm was used to show how visuospatial working memory and the phonological loop are involved in processing scientific texts and illustrations presented via computer. In experiment 1, two presentation formats were compared: text-only and text-with-illustrations. With a concurrent tapping task, the beneficial effect of illustrations disappeared, while a concurrent articulatory task impaired performance similarly in both presentation formats. An analysis of individual differences revealed that this pattern of results was present in high, but not low spatial span subjects. These results support the selective involvement of visuospatial working memory in processing illustrated texts. In Experiment 2, the text-only presentation format was compared to an illustrations-only format. The concurrent articulatory task selectively impaired text-only processing, compared with processing illustrations-only. In addition, this pattern of results was found for high, but not low digit span subjects. These results suggest that individual differences define the extent to which the two subsystems of working memory are involved in learning from multimedia. These two subsystems would be mainly involved in the maintenance of a visual trace of illustrations and of a verbatim representation of linguistic information respectively, these representations being the basis for higher-level comprehension processes. Copyright © 2002 John Wiley & Sons, Ltd. [source] | ||||||||||