Working memory structure in children: comparing different models during childhood

Escritos de Psicología, Vol. 5, nº 2, pp. 27-38 Mayo-Agosto 2012 Copyright © 2012 Escritos de Psicología ISSN 1989-3809 DOI: 10.5231/psy.writ.2012.1904 Working Memory Structure in Children: Comparing Different Models During Childhood Estructura de la Memoria Operativa: Comparando diferentes modelos en la infancia Irene Injoque-Ricle, Juan Pablo Barreyro, & Débora I. Burin Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET) - Facultad de Psicología, Universidad de Buenos Aires - Argentina Disponible online 31 de agosto de 2012 Working Memory (WM) is an active memory system responsible for the temporary storage and concurrent processing of information. Different authors have considered WM as a complex but unitary system, whereas others have suggested that the system is multidimensional. In this line, the model developed by Baddeley and Hitch (1974) is one of the most well known; it proposes two modality-specific components - the phonological loop and the visuo-spatial sketchpad - and a supervisory executive system - the central executive. This paper contributes to the debate on WM structure by investigating three groups of children of different ages and assessing different models using confirmatory factor analysis. The Working Memory Assessment Battery Test (Alloway, 2007; Injoque-Ricle, Calero, Alloway & Burin, 2011) was administered to 180 monolingual Spanish-speaking children. The three age groups consisted of 6-, 8-, and 11-year-old children (n = 60 participants per group). The results suggest that the WM structure is not uniform across the different age groups tested, showing progressive differentiation and specialization during childhood. This structure would appear to form between the ages of 6 and 8 years and become more complex as adolescence is approached. Keywords: Working Memory; Confirmatory Factor Analysis; Children; AWMA. La Memoria Operativa (MO) es un sistema de memoria activa responsable del almacenamiento temporal y procesamiento concurrente de información. Diferentes autores han considerado a la MO como un sistema complejo pero unitario, otros sugieren una estructura más compleja. Uno de los modelos más aceptados es el de Baddeley y Hitch (1974) que propone dos componentes de modalidad específica, el Bucle Fonológico y la Agenda Viso-Espacial, y un sistema ejecutivo supervisor, el Ejecutivo Central. El objetivo de este trabajo es contribuir al debate de la estructura de la MO en tres grupos de edades de niños, evaluando diferentes modelos, a través de un análisis factorial confirmatorio. Se administró la Batería Automatizada de Memoria Operativa (Alloway, 2007; Injoque-Ricle, Calero, Alloway & Burin, 2011) a 180 niños de habla española, distribuidos en tres grupos de edades (60 sujetos cada uno) de 6, 8 y 11 años. Los resultados sugieren que la estructura de la MO no sería uniforme entre los grupos evaluados, mostrando una diferenciación y especialización a lo largo de la infancia. Entre los 6 y los 8 años comienza a observarse una estructura y se complejiza hacia la adolescencia. Palabras clave: Memoria Operativa; Análisis Factorial Confirmatorio; Niños; AWMA. Correspondence concerning this article should be addressed to: Dra. Irene Injoque-Ricle. Instituto de Investigaciones, Facultad de Psicología, Universidad de Buenos Aires. Av. Independencia 3065 3º Piso, Of. 13, (C1425AAM), Ciudad de Buenos Aires, Argentina. E-mail: . Authors’ E-mails: Dr. Juan Pablo Barreyro: . Dra. Débora I. Burin: This research was supported by the Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET; Res. Nº 258/06 and Res. N° 3100/08) and by the Secretaría de Ciencia y Técnica, Universidad de Buenos Aires (SECyT; UBACyT P016). The Automated Working Memory Assessment battery was translated and reproduced by Permission. Copyright © 2007 by Harcourt Assessment. Spanish Translation copyright © 2007 by Harcourt Assessment. All rights reserved. 27 IRENE INJOQUE-RICLE, JUAN PABLO BARREYRO, DÉBORA I. BURIN When we use the term working memory capacity, we refer to the attentional processes that allow for goal-directed behavior by maintaining relevant information in an active, easily accessible state outside of conscious focus, or to retrieve that information from inactive memory, under conditions of interference, distraction, or conflict (Kane, Conway, Hambrick & Engle, 2007, p. 23). Even when factor analysis has shown two different components in WM, a short term maintenance one and another for long term memory retrieval (Engle & Kane, 2004; Unsworth & Engle, 2007; Unsworth et al., 2009), or a short term memory factor and a WM one (Conway et al., 2002; Engle et al., 1999; Kane et al., 2004; Oberauer, Süb, Schulze, Wilhelm & Wittmann, 2000; Süb et al., 2002), this research perspective has considered that due to the great amount of shared variance between the tests and their high correlations with different measures of cognitive abilities, the unitary model is the most plausible. A second line of research suggests a fractioning within WM. One of the most accepted models is the one developed by Baddeley and Hitch (Baddeley, 1986, 1999a, 2007; Baddeley & Hitch, 1974). According to this model, WM has two modality specific components, the phonological loop (PL), for the maintenance of verbal material, and the visuo-spatial sketchpad (VSSP) for the maintenance of visuo-spatial information; and a supervisory executive system, the central executive (CE), amodal and devoid of storage resources. The CE is a flexible system responsible for the control and regulation of the two slave systems (Baddeley, 1999a, 1999b, 2007; Baddeley & Logie, 1999; Gathercole, Pickering, Ambridge & Wearing, 2004). The most recent version of the model includes a third subsystem: the Episodic Buffer. This subsystem uses multidimensional codes to form an episodic representation. Due to this integration it works as an interface between different subsystems (Baddeley, 2000). This new component doesn’t have the same empirical support than the original ones (Alloway, Gathercole, Willis & Adams, 2004; Repovs & Baddeley, 2006), so most WM research is based on the original model. Another line of research has studied maintenance in the modal stores, and maintenance plus concurrent processing separately, sometimes referred as short-term and working memory, respectively (e.g. Baddeley, 1992, 2007; Conway et al., 2002; Engle et al., 1999; Gathercole & Baddeley, 1989; Gathercole & Hitch, 1993; Papagno & Vallar, 1992; Swanson & Howell, 2001; Tillman, Nyberg & Bohlin, 2008). Verbal information storage in the PL is assessed as verbal short term memory (VSTM), and the capacity to process verbal information while storing in the PL, is termed verbal working memory (VWM). The same happens when the information modality is visuospatial: visuo-spatial short term memory (VSSTM) or visuospatial working memory (VSWM) is assessed. Within VSWM a subdivision between visual WM and spatial WM (Baddeley & L (...truncated)