Bjo ¨ rn Lyxell *,§ Birgitta Sahle ´n $ Malin Wass *,§ Tina Ibertsson $ Birgitta Larsby *,% Mathias Ha ¨ llgren *,% Elina Ma ¨ ki-Torkko % * The Swedish Institute for Disability Research, Linko ¨ping University, Linko ¨ping, Sweden § Department of Behavioural Sciences, Linko ¨ping University, Linko ¨ ping, Sweden $ Department of Clinical Sciences, Lund University, Lund, Sweden % Department of Clinical and Experimental Medicine, Lund University, Lund Sweden Key Words Cochlear implant Behavioural measures Psychoacoustics/hearing science Paediatric Abbreviations CI: Cochlear implant Original Article International Journal of Audiology 2008; 47 (Suppl. 2):S47S52 Cognitive development in children with cochlear implants: Relations to reading and communication Abstract The purpose of the present article is to present an overview of a set of studies conducted in our own laboratory on cognitive and communicative development in children with cochlear implants (CI). The results demonstrate that children with CIs perform at signifi- cantly lower levels on the majority of the cognitive tasks. The exceptions to this trend are tasks with relatively lower demands on phonological processing. A fairly high proportion of the children can reach a level of reading comprehension that matches hearing children, despite the fact that they have relatively poor phonological skills. General working memory capacity is further correlated with the type of questions asked in a referential commu- nication task. The results are discussed with respect to issues related to education and rehabilitation. Sumario El propo ´sito de este artı ´culo es presentar una perspectiva de una serie de estudios realizados en nuestro laboratorio sobre el desarrollo cognitivo y comunicativo de nin ˜ os con implante coclear (IC). Los resultados demuestran que los nin ˜os con IC rinden en niveles significativamente ma ´s bajos en la mayorı ´a de las tareas cognitivas. Las excepciones a esta tendencia son las tareas que tienen una demanda relativamente menor en el procesamiento fonolo ´gico. Una buena proporcio ´n de los nin ˜os pueden alcanzar niveles de comprensio ´n de la lectura equipar- ables a los de nin ˜os oyentes, a pesar del hecho de que tienen habilidades fonolo ´gicas relativamente pobres. La capacidad de memoria general se correlaciona adema ´s con el tipo de preguntas presentadas en una tarea referencial de comunicacio ´ n. Se discuten los resultados con respecto a lo relacionado con la educacio ´n y la rehabilitacio ´n. A cochlear implant (CI) provides auditory sensations to children with severe or profound hearing impairment, and the auditory sensations open up the possibility of a different course of development in a wider variety of areas related to communica- tion than would have been the case without the CI (Geers et al, 2003; Houston et al, 2003, Richter et al, 2002; Spencer, 2004; Wass et al, 2007). This is a developmental trend that is most pronounced in areas where processing of cognitive and language- related information is central (e.g. working memory, phonologi- cal skills, and reading; Geers, in press; Dillon & Pisoni, 2004; Pisoni et al, in press). Previous research also demonstrates that demographic factors such as age at implant, duration of deaf- ness, and time with the CI may have an impact on the course of development (Richter et al, 2002; Snik et al, 1997). Children with CI have a different development of basic academic skills such as language and reading skills, compared both with children with normal hearing (Normand et al, 2003), and compared with children with severe deafness, who have not been implanted (Truy et al, 1998). A central feature of the empirical picture is that early implantation is more beneficial for development than implantation at a later age (Connor & Zwolan, 2004; Tait et al, 2007; Pisoni et al, in press; Sharma et al, 2005; Wass et al, 2007). In the present paper we will give an overview of results from a set of studies focusing on the development of working memory capacity, phonological processing skills, and lexical abilities and how these three relate to reading and communication skills. Working memory capacity, phonological processing skills, and lexical abilities are cognitive components that are central for processing of information in most language-related activities (e.g. reading, speech understanding, communication). Further- more, they are composite skills such that they are constituted by a number of different sub-components, where each sub-compo- nent serves a specific purpose (e.g. the phonological loop, which is responsible for processing and storage of phonological information in the working memory system, Repovs & Baddeley, 2006). A general strategy has been to examine three to five sub- components within each of the three components. This strategy will enable us to study whether the auditory stimulation from the CI promotes a general development (i.e. all sub-components) or whether the benefits of CI are restricted to some specific sub- component (e.g. the phonological loop in working memory). Previous research on working memory in children with CI has demonstrated that their phonological storage capacity varies widely among the children. Dillon (2004), using a nonword ISSN 1499-2027 print/ISSN 1708-8186 online DOI: 10.1080/14992020802307370 # 2008 British Society of Audiology, International Society of Audiology, and Nordic Audiological Society Bjorn Lyxell Department of Behavioural Sciences, Linko ¨ping University, Linko ¨ ping, S-58183, Sweden. E-mail: Bjorn.Lyxell@liu.se Received: June 26, 2008 Accepted: June 27, 2008