The efficacy of working-memory training is a topic of considerable debate, with some studies showing transfer to measures such as fluid intelligence while others have not. We report the results of a study designed to examine two forms of working-memory training, one using a spatial n-back and the other a verbal complex span. Thirty-one undergraduates completed 4 weeks of n-back training and 32 completed 4 weeks of verbal complex span training. We also included two active control groups. One group trained on a non-adaptive version of nback and the other trained on a real-time strategy video game. All participants completed pre-and post-training measures of a large battery of transfer tasks used to create composite measures of short-term and working memory in both verbal and visuospatial domains as well as verbal reasoning and fluid intelligence. We only found clear evidence for near transfer from the spatial n-back training to new forms of n-back, and this was the case for both adaptive and non-adaptive n-back.
Keywords Working memoryWorking memory is of great interest across psychology. Defined as the ability to simultaneously store and process information in the service of a goal (Baddeley, 1992; Miyake & Shah, 1999), working memory is frequently measured by performance on computerized tasks where one must remember a series of items while performing accurately on an interleaved secondary task such as reading a sentence or solving arithmetic problems (Daneman & Carpenter, 1980;Turner & Engle, 1989). What makes the construct so central is its ability to predict performance on a wide array of complex cognitive tasks such as reading and language comprehension (Daneman & Carpenter, 1980;Daneman & Merikle, 1996), reasoning (Kyllonen & Christal, 1990), and mathematical (LeFevre, DeStefano, Coleman, & Shanahan, 2005) performance as well as measures of fluid intelligence (Kane, Conway, Hambrick, & Engle, 2007). Additionally, poor working-memory performance is seen in disorders such as attention-deficit hyperactivity disorder (ADHD; Barkley, 1997), schizophrenia (Goldman-Rakic, 1994), and learning disabilities (Swanson, 2006). Therefore, a natural question is whether improvements in working-memory capacity will lead to improved performance on complex tasks.The broader question of whether cognitive enhancement can be achieved through the training of basic cognitive tasks is an old one (Thorndike & Woodworth, 1901), but the 21st century has seen a growing number of studies suggesting that such training regimens can be effective, especially when working memory is the target. Klingberg, Forssberg, and Westerberg (2002) reported that the use of a computerized working-memory program in children with ADHD showed transferable improvements to working memory as well as a measure of fluid intelligence. One feature deemed critical for success was the adaptive nature of their program, i.e. the difficulty was constantly adjusted for each individual based on their current performance so they would always be challenged but not...
