Limitations and chances of working memory training

Limitations and chances of working memory training Daniela Nussbaumer (nussbaumer@ifv.gess.ethz.ch) Institute for Behavioral Sciences, ETH Zurich, Universitatsstrasse 41 8092 Zurich, Switzerland Roland H. Grabner (roland.grabner@psych.uni-goettingen.de) Department of Psychology, Georg-August-University of Gottingen, Waldweg 26 37073 Gottingen, Germany Michael Schneider (m.schneider@uni-trier.de) Department of Psychology, University of Trier, Universitatsring 15 54296 Trier, Germany Elsbeth Stern (stern@ifv.gess.ethz.ch) Institute for Behavioral Sciences, ETH Zurich, Universitatsstrasse 41 8092 Zurich, Switzerland Abstract Recent studies show controversial results on the trainability of working memory (WM) capacity being a limiting factor of human cognition. In order to contribute to this open question we investigated if participants improve in trained tasks and whether gains generalize to untrained WM tasks, mathematical problem solving and intelligence tests. 83 adults trained over a three week period (7.5 hours total) in one of the following conditions: A high, a medium or a low WM load group. The present findings show that task specific characteristics could be learned but that there was no transfer between trained and untrained tasks which had no common elements. Positive transfer occurred between two tasks focusing on inhibitory processes. It might be possible to enhance this specific component of WM but not WM capacity as such. A possible enhancement in a learning test is of high educational interest and worthwhile to be investigated further. Keywords: inhibition working memory; training; intelligence; Theoretical Background The concept of WM has received much attention lately by various psychological disciplines for its importance as a basis of human intelligence and as a limiting factor of human cognition. WM can be seen as a cognitive system for simultaneously storing and manipulating information, and hence strongly relates to reasoning abilities and the handling of novel information (Baddeley & Hitch, 1974). Also the attention to goal-relevant information and inhibition of irrelevant information are important functions of WM. High correlations between WM capacity and intelligence (Oberauer, Suss, Wilhelm, & Wittmann, 2008), notably when measured by Matrices Tests (e.g. Advanced Progressive Matrices Test; Raven, 1990) as well as high correlations between WM capacity and applied fields, e.g. mathematical problem solving tasks leave the following open question: What happens to intelligence and mathematical problem solving skills when WM capacity potentially gets enhanced? One possibility could be a likewise enhancement of WM and intelligence (and mathematical problem solving skills). The similarity of the two concepts would make far transfer plausible. But as stated earlier, results are controversial and more evidence is needed. Early studies were positive in judging the possibility of a WM training being able to enhance WM capacity and performance in related fields. These early studies were also more explorative in nature. Later studies took criticism (Moody, 2009; Sternberg, 2008) into consideration and the complexity of study designs has been raised (for example by Redick et al. (2012) a non-replication of the study by Jaeggi, Buschkuehl, Jonides, & Perrig, (2008)). In the current study the following criticisms of the past studies are taken into consideration and examined: a) inclusion of an active control group, b) administering a wide variety of transfer tasks and c) examining long term effects. The trainability of WM capacity would mean that we are able to broaden an important limiting factor of human cognition and this would be of highly practical as well as of seminal educational relevance. There is a growing body of WM training literature (Chein & Morrison, 2010; Klingberg, 2010; Shipstead, Redick, & Engle, 2012). Melby-Lervag and Hulme (2012) conducted a meta-analytic study and compared effects: Across training studies, effects vary in whether WM training paradigms are effective in improving cognitive abilities. We included three training groups: a high, a medium and a high WM load group. Their training differed in the amount as well as in the type of WM load included. The first two groups focused on resolution of proactive interference – an ability tapping the WM subcomponent of inhibition, which is regarded as critical subcomponent of WM (Friedman & Miyake, 2004). The third group was an active control group (low to zero WM load) solving a control reaction time task. The further manipulations