Showing posts with label quantitative knowledge. Show all posts
Showing posts with label quantitative knowledge. Show all posts

Wednesday, April 20, 2011

Research bytes: MS & Gs, numerical development, working memory & bilinguals, Ga-pseudo word repetition tasks, etc




Denney, D. R., Gallagher, K. S., & Lynch, S. G. (2011). Deficits in Processing Speed in Patients with Multiple Sclerosis: Evidence from Explicit and Covert Measures. Archives of Clinical Neuropsychology, 26(2), 110-119

Cognitive slowing in individuals with multiple sclerosis (MS) has been documented by numerous studies employing explicitly timed measures in which speed of responding is an obvious focus of task performance. The present study examined information processing speed in MS patients and controls with a computerized battery of covertly timed as well as explicitly timed measures. The explicit measures were derived from two tests requiring rapid serial processing of visual stimuli, the Stroop Test and a Picture Naming Test. Covert measures were derived from the Rotated Figures Test, Remote Associates Test, and Tower of London, all tasks in which participants’ attention was drawn toward arriving at an accurate solution, and the latency with which they arrived at these solutions was timed by the computer “behind the scenes.” Significant differences in processing speed for patients and controls occurred on both types of measures, although the effect sizes were notably larger on the explicit measures.



Jones, G. (2011). A computational simulation of children's performance across three nonword repetition tests. Cognitive Systems Research, 12(2), 113-121

The nonword repetition test has been regularly used to examine children’s vocabulary acquisition, and yet there is no clear explanation of all of the effects seen in nonword repetition. This paper presents a study of 5–6year-old children’s repetition performance on three nonword repetition tests that vary in the degree of their lexicality. A model of children’s vocabulary acquisition is then presented that captures the children’s performance in all three repetition tests. The model represents a clear explanation of how working memory and long-term lexical and sub-lexical knowledge interact in a way that is able to simulate repetition performance across three nonword tests within the same model and without requiring test specific parameter settings



Bonifacci, P., Giombini, L., Bellocchi, S., & Contento, S. (2011). Speed of processing, anticipation, inhibition and working memory in bilinguals. Developmental Science, 14(2), 256-269.

Literature on the so-called bilingual advantage is directed towards the investigation of whether the mastering of two languages fosters cognitive skills in the non-verbal domain. The present study aimed to evaluate whether the bilingual advantage in non-verbal skills could be best defined as domain-general or domain-specific, and, in the latter case, at identifying the basic cognitive skills involved. Bilingual and monolingual participants were divided into two different age groups (children, youths) and were tested on a battery of elementary cognitive tasks which included a choice reaction time task, a go/no-go task, two working memory tasks (numbers and symbols) and an anticipation task. Bilingual and monolingual children did not differ from each other except for the anticipation task, where bilinguals were found to be faster and more accurate than monolinguals. These findings suggest that anticipation, which has received little attention to date, is an important cognitive domain which needs to be evaluated to a greater extent both in bilingual and monolingual participants



Hyde, D. C., & Spelke, E. S. (2011). Neural signatures of number processing in human infants: evidence for two core systems underlying numerical cognition. Developmental Science, 14(2), 360-371

Behavioral research suggests that two cognitive systems are at the foundations of numerical thinking: one for representing 1–3 objects in parallel and one for representing and comparing large, approximate numerical magnitudes. We tested for dissociable neural signatures of these systems in preverbal infants by recording event-related potentials (ERPs) as 6–7.5-month-old infants (n = 32) viewed dot arrays containing either small (1–3) or large (8–32) sets of objects in a number alternation paradigm. If small and large numbers are represented by the same neural system, then the brain response to the arrays should scale with ratio for both number ranges, a behavioral and brain signature of the approximate numerical magnitude system obtained in animals and in human adults. Contrary to this prediction, a mid-latency positivity (P500) over parietal scalp sites was modulated by the ratio between successive large, but not small, numbers. Conversely, an earlier peaking positivity (P400) over occipital-temporal sites was modulated by the absolute cardinal value of small, but not large, numbers. These results provide evidence for two early developing systems of non-verbal numerical cognition: one that responds to small quantities as individual objects and a second that responds to large quantities as approximate numerical values. These brain signatures are functionally similar to those observed in previous studies of non-symbolic number with adults, suggesting that this dissociation may persist over vast differences in experience and formal training in mathematics


Schleifer, P., & Landerl, K. (2011). Subitizing and counting in typical and atypical development. Developmental Science, 14(2), 280-291.

Enumeration performance in standard dot counting paradigms was investigated for different age groups with typical and atypically poor development of arithmetic skills. Experiment 1 showed a high correspondence between response times and saccadic frequencies for four age groups with typical development. Age differences were more marked for the counting than the subitizing range. In Experiment 2 we found a discontinuity between subitizing and counting for dyscalculic children; however, their subitizing slopes were steeper than those of typically developing control groups, indicating a dysfunctional subitizing mechanism. Across both experiments a number of factors could be identified that affect enumeration in the subitizing and the counting range differentially. These differential patterns further support the assumption of two qualitatively different enumeration processes.

















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Sunday, January 02, 2011

Hot and cold CHC intelligence abilities--Gf,Gc,Gv hot--Ga,Glr cold

Interesting article in the journal Intelligence reviewing the state-of-the-art of factor analysis practices for identifying the g (general intelligence) factors. Abstract is below. Of interest is the use of the CHC framework to classify the type of broad CHC factor indicators found in the research synthesis.

Not unexpectedly, Gf, Gc, and Gv were found most often in IQ factor analysis research, followed by Gq, Gs and Gsm. Abilities that appear underrepresented in IQ factor analysis g research are the domains of Glr and Ga.

However, a couple of major caveats. The literature review was primarily adult samples. There has been considerable factor analysis activity with tests in childhood and adolescent samples that might increase the proportion of Glr and Ga indicators. Also, the authors did not include journals favored by those doing research in school psychology, special education, and speech and language---fields of study that most likely have published more studies in the under-represented CHC domains.

Never-the-less......the general trends are not surprising.

Clicking on images should take you toe larger versions.






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Tuesday, December 14, 2010

Research bytes: Cognitive employment testing--aging strategies--cognitive thresholds

Three interesting articles from one of my favorite journals--Current Directions in Psychological Science.

As per usual when I make a research byte/brief post, if anyone would like to read the original article, I can share via email---with the understanding that the article is provided in exchange for a brief guest post about it's contents. :) (contact me at iap@earthlink.net if interested). Also, if figure/images are included in the post, they can usually be made larger by clicking on the image.












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Thursday, November 25, 2010

Research byte: Foundational numerical capacities and math disabilities (dyscalculia)

Interesting article in a special issue of Trends in Cognitive Science--Space, Time and Number

Foundational numerical capacities and the origins of dyscalculia, by Brian Butterworth. Trends in Cognitive Sciences, December 2010, Vol. 14, No. 12

Abstract

One important cause of very low attainment in arithmetic (dyscalculia) seems to be a core deficit in an inherited foundational capacity for numbers. According to one set of hypotheses, arithmetic ability is built on an inherited system responsible for representing approximate numer-osity. One account holds that this is supported by a system for representing exactly a small number (less than or equal to four4) of individual objects. In these approaches, the core deficit in dyscalculia lies in either of these systems. An alternative proposal holds that the deficit lies in an inherited system for sets of objects and operations on them (numerosity coding) on which arith-metic is built. I argue that a deficit in numerosity coding, not in the approximate number system or the small number system, is responsible for dyscalculia. Neverthe-less, critical tests should involve both longitudinal studies and intervention, and these have yet to be carried out.



As per usual when I make a research byte/brief post, if anyone would like to read the original article, I can share via email---with the understanding that the article is provided in exchange for a brief guest post about it's contents. :) (contact me at iap@earthlink.net if interested). Also, if figure/images are included in the post, they can usually be made larger by clicking on the image.


- iPost using BlogPress from my Kevin McGrew's iPad