Chapter 7 Brain Training and Cognition

Alina Korovatskaya, The Graduate Center CUNY, Spring 2018

7.1 Abstract

“Brain training” is something most people have heard of, and there are many techniques and methods that claim to improve one’s cognition and enhance one’s brain. These techniques vary from learning how to play chess or music to various cognitive training programs to ordinary exercise activities. But do these techniques work? Can we really do something that will make us smarter or better at tasks? This topic and these techniques are quiet controversial because there are studies that provide evidence for a positive outcome of these training techniques, but their evidence lack in generalization and long-term effects. This paper is a review of various research articles that talk about different brain training techniques, including playing chess or musical instruments, different cognitive trainings, such as brain training games, bilingual brain training, and working memory training, and fitness training and exercises, and provided evidence for these techniques, if any. Limitations of these techniques are discussed as well.

7.2 Introduction

“Brain training” is something most people have heard of. It promises that with certain techniques and training people will improve their cognitive abilities, become smarter and better at various tasks by improving working memory, attention, executive functions, reasoning skills and speed information processing (van Heugten at al., 2016). And the amount of these techniques and programs is truly endless. There is a lot to choose from, from mobile apps to cognition enhancing drugs, and each of these programs or techniques promises astonishing results. Seems great, but there’s yet another side to the story because the topic of brain training is controversial. People “often rely on claims that are scientifically unsubstantiated” (Rabipour and Raz, 2012). There are studies that provide evidence for a positive outcome of various training techniques, but their evidence lack in generalization and long-term effects. That is, people who engaged in these training programs showed improvement in trained tasks, but there were no evidence of improving in untrained tasks neither in the same cognitive domain nor in different cognitive domain (Wilson, 1997).

There are many techniques and methods offered that claim to improve one’s cognition and enhance one’s brain. These techniques vary from special cognition enhancing drugs to learning how to play chess or music to various cognitive training programs, including brain training games, bilingual training, and working memory training, to ordinary exercise activities. Many people try them, and it might seem like many of these techniques indeed work, or, at least, that is what advertised by developers of those techniques and programs. But do they really work? To what degree? Which techniques and programs are better? Can we really do something that will make us smarter or better at a wide range of cognitive tasks and delay decline in cognitive abilities? Is there enough scientific evidence that can show, “Yes, this program will improve your brain”? How about long-term effect? Or are these training programs can only enhance one’s brains for a certain amount of time?

This paper will examine various research studies that were focused on different brain training techniques that claim to improve cognition. These techniques include ability to play chess and music, playing brain training games, improving working memory, speaking two languages, and fitness training. Section 2 will analyze whether playing chess or a musical instrument makes you better at other tasks. Section 3 will discuss different cognitive trainings, including brain training games, bilingual brain training, and working memory training as ways to enhance cognitive functions. Section 4 will look at various examples of cognitive improvement with fitness training and exercises in elderly adults. Section 5 will talk about some limitation of previous research and possible future implications for brain training research. Section 6 would be a brief summary of reviewed studies and a conclusion.

7.3 Chess and Music

7.3.1 Near and Far Transfer

It is often claimed that chess players and musicians are smarter and better at various task than those who doesn’t know how to play chess or a music instrument. Giovanni Sala and Fernand Gobet in “Does far transfer exits? Negative evidence from chess, music, and working memory training” talked about evidence, or rather lack of evidence that could support the idea of far transfer in chess masters and musicians.

First of all, what is far transfer? What kind of transfers exists? The answer is there are two types of transfer of learning: near transfer and far transfer. Near transfer is “the generalization of a set of skills across two (or more) domains tightly related to each other” (Sala and Gobet, 2017). For example, if you know how to drive an SUV, you will be able to drive a sedan. Far transfer, on the other hand, occurs “when a set of skills generalizes across two (or more) domains that are only loosely related to each other” (Sala and Gobet, 2017). An example of a far transfer would be when studying mathematics helps you learn a foreign language. It is known that near transfer takes place often, while far transfer is not as common (Thorndike and Woodworth, 1901). This theory is supported by the majority of studies, which suggest that cognitive improvement do not transfer to new tasks or transfer only to tasks with the same processing requirements as the trained tasks (Ball et al., 2002; Mahncke et al., 2006; Basak et al., 2008). Nevertheless, some researchers still believe in far transfer from chess and music to other domains because it is assumed that these activities (chess and music) require domain-general cognitive abilities that can be trained by practice in a specific domain. Sala and Gobet (2017) tested this hypothesis by conducting multiple meta-analyses.

7.3.2 A Meta-Analysis Study

People who are engaged in intellectual activities show overall better cognitive abilities when compared with general population. For example, more skilled chess players show higher level of cognitive abilities (Sala and Gobet, 2017). Burgoyne et al. (2016) also reported a significant correlation between chess skill and four broad measures of cognitive ability: fluid intelligence, processing speed, short-term memory and working memory, and comprehension knowledge. To be more specific, fluid intelligence is the ability to solve new problems; processing speed is the efficiency of basic mental operations; short-term and working memory is the ability to retain, change, and recall information over a short period of time and comprehension knowledge is the ability to use knowledge gained through experience. Schellenberg (2006) and Lee, Lu, and Ko (2007) also reported positive correlations between music skill, working memory, and IQ. However, positive correlation between chess or music and cognitive ability doesn’t tell anything about far transfer (Sala and Gobet, 2017). But researchers believe in presence of far transfer from chess or music to other domains because these activities enhance general intelligence and have a positive effect on cognitive abilities in other domains (Schellenberg, 2006). Same goes for the theory about far transfer and action-video-game training. However, this theory that action-video-game training can enhance one’s performance in a broad set of visuo-attentional and cognitive tasks was challenged by Oei and Patterson (2015). They used four different action games and showed that participants’ improvements were limited only to those cognitive abilities that were targeted in the game played.

Sala and Gobet (2017) tested this hypothesis by running three meta-analyses, focusing on children and young adolescence. The results showed small overall effect sizes in all three meta-analyses, which is not that promising. Simons et al. (2016) also observed no evidence of far transfer benefits from brain-training programs. Although some working memory training programs claimed to improve participants’ performance on various cognitive tasks, studies with a strong experimental design showed no far-transfer effects.

7.3.3 Patterns in Findings

There are a few patterns that can be seen in various studies of effects of chess and music skills on cognitive abilities and far transfer. First of all, people who are engaged in cognitive activities like chess or music have better overall cognitive ability than others. Second, training chess, music, or working memory skills doesn’t enhance one’s skills beyond those that they train. Third, there is no far transfer effect to other domains when training music or chess skills (Sala and Gobet, 2017). Due to a lack of good evidence, it can be concluded that playing chess or music doesn’t make people smarter. Rather, smarter people are more likely to engage and excel in these activities because, no doubt, cognitive ability correlates with domain-specific skills.

7.4 Cognitive Training

With age, people’s cognitive abilities tend to decline. Our memory, attention, ability to maintain and manipulate information gets worse. There are many different kinds of interventions that have been proposed to help maintain our cognitive abilities. Some recommend rudimentary pencil-and-paper type tasks (crosswords), more advanced computer/video-game type programs (Lumosity), or nutritional supplements (caffeine). Others suggest various drugs (Parsons et al., 2014). All of these interventions suppose to suppress and slow down this decline in cognitive abilities and delay such diseases as dementia or Alzheimer’s disease. But drugs do little to none to maintain cognitive and functional abilities or to slow the progress of the diseases (Kueider et al., 2014). On the other hand, mental exercises seem to do a better job when it comes to improving cognitive abilities. Previous study showed that multiple cognitive training programs could improve cognitive functions like memory (Smith et al., 2009), processing speed (Ball et al., 2007), executive function (Uchida and Kawashima, 2008), and attention (Mozolic et al., 2011) in healthy older adults. Cognitive training is based on the idea that out brain can change for the better, even in old age. In the same way that physical training improves physical abilities, cognitive training improves cognitive abilities.

7.5 Cognitive Training Programs: Do They Work?

7.5.1 Brain Training Games

In “Brain training game improves executive functions and processing speed in the elderly: A randomized controlled trial,” Nouchi et al. (2012) examined video game training as one of the types of cognitive training in older adults because some of the previous studies showed that playing video games can lead to improvement in some cognitive functions in older adults. For their study they recruited 32 elderly healthy adults who were divided into two groups: one group played Brain Age game, and another group played Tetris. Brain Age game was published by Nintendo in 2005 and was one of the most popular brain training games. The game was developed based on the previous cognitive training for older adults. Participants in both Brain Age and Tetris groups played for about 15 minutes per day, at least 5 days per week, for 4 weeks (prior to the experiment participants were non-gamers and reported playing video games for less than one hour a week for the past two years).

Cognitive functions that were measured were divided into four categories: global cognitive status, executive function, attention, and processing speed. Measures of cognitive functions were conducted before and after training. After the experiment, their result showed that playing Brain Age in short term training could help improve such cognitive functions as executive functions and processing functions in older adults. However, there was no difference between playing Brain Age or Tetris when they measured global cognitive statuses. Also, neither game improved attention. These finding were consistent with some of the previous evidence that playing certain games can help improve cognitive functions in older adults (Basak et al., 2008). But they didn’t study any long-term effects, which is an important part when it comes to determining if a particular game can indeed be used to improve cognitive abilities in older people. And, as authors indicated themselves, a study with a larger number of participants would be necessary to confirm the present results.

7.5.2 Bilingual Brain Training

In “Bilingual brain training: A neurobiological framework of how bilingual experience improves executive function,” Stocco et al., (2014) made an interesting point that bilingualism helps “train the brain.” They stated that individuals who are bilingual often outperform monolinguals on tests of executive functions. Executive functions are defined as activities that can be dissociated from one another to a certain extent, like inhibition, shifting, and updating. Bilingual advantage on such tests has been well documented (Bialystok, 2009). This is due to the fact that demands for language selection and switching in bilinguals directly overlaps with the inhibition and shifting components of executive function.

Miyake et al. (2000) stated that bilinguals have advantage in executive function because it reflects a superior capacity for inhibitory control, or “the capacity of controlling and halting dominant and automatic responses that are strongly associated to environmental stimuli but are not appropriate for the current task” (Stocco et al., 2014). Bilingual have to deal with interfering responses from the unwanted language (responses that are normally activated in parallel with those of the target language) (Bialystok, 2001). However, more recent studies suggest that improved inhibitory control may not be the best characterizations of bilinguals’ cognitive advantages (Festman et al., 2010).

Yet, Miyake et al. (2000) had another explanation for bilinguals’ advantage in executive function. They suggested that it can also be explained by the fact that bilinguals are better at the shifting component of complex tasks, or “the capacity of flexibly switching back and forth between multiple tasks, mental operations, or response sets” (Stocco et al., 2014). This assumption is based on the fact that, in order to be fluent bilinguals, people need to switch effectively between relative grammatical rules and phonological outputs for each of the languages they speak. Therefore bilinguals have a lot of practice with shifting and gain more benefits from it. People who can easily switch between two languages are proven to perform better on all executive function tasks than people who lack the ability to switch between languages effectively (Festman et al., 2010). That can be a proof that the capacity to switch between languages is closely related to having better executive functions.

It is evident that bilinguals have advantages over monolinguals. Bilingual practice can be adopted to improve cognitive performance and rehabilitate cognitive decline because extensive training in task switching results in general cognitive benefits.

7.5.3 Working Memory Training

Working memory is a capacity limited system that serves as the workplace of our mind and its size can determine or ability to perform various cognitive tasks (Kane et al., 2004). Although it was assumed that working memory capacity has a limit, but more recent studies suggested that working memory capacity can be expanded with targeted training (Klingberg et al., 2005). In “Does working memory training work? The promise and challenges of enhancing cognition by training working memory,” Morrison and Chein (2010) discussed working memory training as a tool for broad cognitive benefits. They identified two approaches to working memory training: strategy training and core training.

“Strategy training paradigms involve teaching of effective approaches to encoding, maintenance, and/or retrieval from working memory” (Morrison and Chein, 2010). The main goal of the majority of strategy training studies is to increase performance in tasks that require retention of information over a delay. In strategy training studies, participants are introduced to specific task strategies and then provided with practice sessions encouraging the strategy of interest. Morrison and Chein (2010) found out that training-related increases in working memory capacity have been successfully demonstrated across a wide range of subject populations, but different training techniques seem to produce different impact upon the broader range of cognitive abilities. They also mentioned that the amount of information remembered on measures of working memory can be increased by teaching strategies like rehearsing out loud, telling a story with a stimuli, using imagery to make stimuli salient.

“Core training studies typically involve repetition of demanding working memory tasks that are designed to target domain-general working memory mechanisms” (Morrison and Chein, 2010). Thus tasks for core training programs usually involve sequential processing and frequent memory updating and are designed to decrease the use of domain-specific strategies, limit automization, include stimuli that span multiple modalities, enforce fast working memory encoding and retrieval, and demand high cognitive workload. Morrison and Chein (2010) identified that it produced more far-reaching transfer effects, probably because they targeted domain-general mechanisms of working memory.

7.6 Fitness/Physical activities

Aside from many negative reviews on brain training techniques, there are some studies that suggest that people can improve their cognitive functions with some physical activities and training.

Unfortunately, with age, older adults show decline in cognitive abilities (Salthouse, 2004). Research shows a decline in abilities of working memory, long-term memory, dual-tasking, task switching, and processing speed (Park et al., 2002; Verhaeghen and Cerella, 2002; Salthouse, 2004). Research claims that “aerobic fitness training enhances the cognitive vitality of healthy but sedentary adults” (Colcombe and Kramer, 2003). Studies of the relationship between cognition and physical training go back several decades; one of the first researches in this area was Spirduso and her colleagues. It was observed that the performance of the older athletes was better than the performance of the older sedentary adults, but for younger sedentary adults the benefit of fitness was not so significant (Spirduso and Clifford, 1978). Aerobic physical activity interventions (like swimming or power-walking) have been associated with improved attention (Colcombe et al., 2004) and executive control processes, like switching (Colcombe and Kramer, 2003).

7.6.1 A Meta-Analysis Study

In “Fitness effect on the cognitive function of older adults: A Meta-analysis study,” Stanley Colcombe and Arthur F. Kramer (2003) talked about several studies that reported a positive effect on cognitive vitality of older adults who were engaged in physical activities. They examined four theoretical hypotheses (speed hypothesis, visuospatial hypothesis, controlled-procesing hypothesis, and executive-control hypothesis) that could affect the extent to which enhancements in aerobic fitness results in improvement in cognition (Rosenthal, 1998). Colcombe and Kramer were interested in the effect of exercise on cognitive functions identified by these four theoretical positions: speed, visuospatial, controlled processing, and executive control. They divided participants by age in three groups: young-old (56-65), middle-old (66-70), and old-old (71+). The training interventions included a large variety of activities from walking and dancing to circuit training, but were divided into two groups: aerobics and combination. Aerobics included exercises that emphasized cardiovascular fitness in isolation, and combination included exercises that combined cardiovascular fitness and strength training. Duration of the sessions also varied: short (15-30 min), moderate (31-45 min), and long (46-60 min), as well as the length if the exercise intervention: short (1-3 months), medium (4-6 months), and long (6+ months). Authors reported that on average fitness training did improve participants’ performance by 0.5 SD (standard deviation) in various cognitive processes in the four theoretical positions mentioned above. Colcombe and Kramer also stated that performing combined strength and aerobic training was more effective than aerobic training alone. However, it is also mentioned that more clinical studies are required to make sure that these results were not influenced by such factors as general health or education, but rather these training programs are indeed as efficient as they are claimed to be.

7.7 Combining Cognitive and Aerobic Training

In “Does combined cognitive training and physical activity training enhance cognitive abilities more than either one alone? A four-condition randomized controlled trial among healthy older adults,” Evelyn Shatil (2013) examined the separate and combined effects of cognitive and aerobic training on four groups of healthy older adults. Four groups of older adults participated in four months cognitive and/or mild aerobic training. Based on the results it was concluded that older adults who engaged in cognitive training (separately or combined) showed a significant improvement in cognitive performance when compared to older adults who didn’t engage in cognitive training. The improvement was shown in cognitive performance on Hand-Eye Coordination, working memory and long-term memory, Seed of Information Processing, Visual Scanning, and Naming. Shatil’s hypothesis was that combining physical activity with cognitive training would yield significantly larger cognitive benefits than physical activity or cognitive training separately, which, indeed, was the result of the study. The differences and improvements held true not only between the groups but also within the groups.

7.7.1 Problems with the research

One important point to keep in mind is that all of these studies were done with healthy older adults. Even though these studies show improvement in cognitive abilities in older adults, whether fitness training has the same effect on cognition in younger adults or young people is to be determined. More scientific studies are needed to examine if active fitness regimen is as beneficial for young people as it is for older adults and what are the benefits of performing regular physical activities from early on in life. In addition, there are no studies with older adults that have any kind of diseases, like Alzheimer’s diseases, for example (Shatil, 2013). Will physical activities help those people that are not as healthy as the participants in all presented studies?

A few more points to mention, while it is evident that fitness does improve cognitive abilities in older adults, it is important to develop a range of aerobic exercises that could be performed while sitting in order to accommodate those participants who are the oldest or have a high risk of falling (Shatil, 2013). Also, not many studies examine or observe how long the fitness training should last if people want to see any significant results in improving their cognitive functions. Shatil’s study, for example, lasted only four months, but there is an indication that aerobic training must be practiced at least one whole year to produce any cognitive benefits in sedentary adults (Voss et al., 2010). It is also not clear whether the benefits of physical training have a long-term effect or for how long the improvement lasts if one stops training.

7.8 Limitations and Future Work

Results in resent research on ways to improve cognitive functions seem very promising. It is evident that there brain training techniques that indeed work and help people with their cognitive functions. For example, physical activities help older adults to maintain or improve cognitive processing that inevitably decline with age: speed, visuospatial, controlled processing, and executive control (Shatil, 2013). So do some of the brain training games (Nouchi et al., 2012). Knowing more than one language also seems to help with our executive functions (Stocco et al., 2014). And some studies encourage optimism regarding working memory training as a tool for cognitive enhancement (Morrison and Chein, 2010).

However, people should investigate these results closely. While they seem promising and optimistic, there are still a lot of questions for these studies and their results. These are the four main concerns researchers should address when conducting new experiments with brain training programs: examining long-term effects of the training, applying training to people of various age, trying to identify whether these programs work on people who are not healthy and have either physical or mental disorders; identifying whether performing activities for cognitive enhancement individually or in a group setting affects the final results.

7.8.1 Long-Term Effects

These studies didn’t examine a long-term effect of any of these brain training programs. Most of the evidence regarding improved cognitive functions was reported right after the end of the appropriate experiment, which resulted in the immediate effect of the training, but there was no follow-up experiment to measure if the results of the training held over a certain amount of time. It would be important to measure if the brain training program has a long-term effect because if it does not, then can this training program be considered as useful? Or would it be not useful without long-term effect?

7.8.2 Various Age Groups

Most of the studies that were reviewed in this paper were focused on participants that are older in age. Even though some brain training games and physical activities do help to enhance cognitive functions in older adults, the question is, would these games and activities be more effective and more beneficial if people start using them at earlier age? If that is the case, why wait until your cognitive functions start to decline and then try to improve them if it can be prevented or delayed at earlier stage? In addition, some of these programs and especially physical activities would be much easier to perfume for those who are younger in age and there will be less risk factors involved in doing such activities.

7.8.3 Participants with Health Problems

One more important limitation in all of the studies mentioned above is that all of them were performed with the participation of healthy individuals. Such things as personal health can have a great effect on the participant’s performance and on the final results of the study. Even though some programs might work for individuals with a good health, those same programs might have little to no effect on individual with health problems or who has an Alzheimer’s disease, for example (Colcombe and Kramer, 2003). It is important to consider not only mental health of a person, but their physical condition as well. Some active exercise programs may be suitable for some and not suitable for other, therefore scientists need to develop a program that could be performed by people in different physical conditions or a range of programs that would provide the same cognitive benefits to people but would be suitable for people in various physical conditions.

7.8.4 Individual vs. Group Setting

One more interesting aspect that can influence performance and the outcome of the training is individual vs. group setting. This is especially true for physical training because physical activities can be performed individually or in groups. Since aerobic training and other fitness activities are claimed to improve participants’ cognitive functions, it would be interesting to see whether a greater effect can be achieved if participants have support and feedback from those who participates in the same fitness program. Positive feedback from peers in a group setting may increase one’s desire to continue with the raining or to try to work harder and better, while no such feedback is available during individual training, therefore there is a high possibility for the lack of motivation.

Addressing these issues in future studies could help make brain training less controversial and more beneficial for people. First of all, addressing issues such as age of the participants and participants who have any mental or physical diseases would account for a wider range of users. And studying long-term effect and benefits of various programs in different settings (individual vs. group) would help identify which brain training programs indeed work and which ones work the best.

7.9 Conclusion

In this paper we took a look at different ways to improve one’s cognitive abilities: chess and music, physical training, and various cognitive training programs, including brain training games, bilingual training, and working memory training. Many people will be greatly disappointed, but being good at chess or music doesn’t mean that you’ll be good at everything else. There is not enough scientific evidence of far transfer from the domain on music and chess to other domains, not related to the two above. Near transfer, on the other hand, is known to take place. However, there are training programs that can help people improve our cognitive abilities. Such programs would be fitness training and exercises, brain training games, bilingual training and working memory training. Results of multiple studies show improvement in cognitive abilities in adults after participating in these brain training programs. But despite how promising and optimistic these results might sound, there are still a lot of grey areas and many unanswered questions. More research studies are required to develop better programs that would help improve one’s cognitive abilities despite their age, health or any other factors that might influence the final effect of the programs that are currently promoted on the market. But this is a right step towards improving our cognitive abilities.

7.10 References

Ball, K., Berch, D. B., Helmers, K. F., Jobe, J. B., Leveck, M. D., & Marsiske, M. (2002). Effects of cognitive training interventions with older adults: a randomized controlled trial. JAMA, 288, 2271–2281.

Ball, K., Edwards, J. D., & Ross, A. L. (2007). Cognitive interventions and aging: the impact of speed of processing training on cognitive and everyday functions J. Gerontol. Ser. B, 62B, 19-31.

Basak, C., Boot, W. R., Voss, M. W., & Kramer, A. F. (2008). Can training in a real-time strategy video game attenuate cognitive decline in older adults? Psychol. Aging, 23, 765-777.

Bialystok, E. (2001). Bilingualism in development: Language, literacy and cognition. New York: Cambridge University Press.

Bialystok, E. (2009). Bilingualism: The good, the bad, and the indifferent. Bilingualism: Language and Cognition, 12, 3-11.

Burgoyne, A. P., Sala, G., Gobet, F., Macnamara, B. N., Campitelli, G., & Hambrick, D. Z. (2016). The relationship between cognitive ability and chess skill: A comprehensive meta-analysis. Intelligence, 59, 72-83.

Colcombe, S. & Kramer, A. F. (2003). Fitness effect on the cognitive function of older adults: A Meta-analysis study. Psychological Science, 14(2), 125-30. doi:[10.1111/1467-9280.t01-1-01430](

Festman, J., Rodriguez-Fornells, A., & Münte, T. F. (2010). Individual differences in control of language interference in late bilinguals are mainly related to general executive abilities. Behavioral and Brain Functions, 6, 1-12.

Kane, M., Hambrick, D., Tuholski, S., Wilhelm, O., Payne, T., & Engle, R. (2004). The generality of working memory capacity: A latent-variable approach to verbal and visuospatial memory span and reasoning. Journal of Experimental Psychology: General, 133(2), 189-217. doi:10.1037/0096-3445.133.2.189

Klingberg, T., Fernell, E., Olesen, P. J., Johnson, M., Gustafsson, P., Dahlstrom, K. (2005). Computerized training of working memory in children with ADHD: A randomized, controlled trial. Journal of the American Academy of Child and Adolescent Psychiatry, 44(2), 177-186. doi:10.1097/00004583-200502000-00010

Kueider, A., Bichay, K., & Rebok, G. (2014). Cognitive training for older Adults: What is it and does it work? Issue Brief, 10, 1-8.

Lee, Y., Lu, M., & Ko, H. (2007). Effect of skill training on working memory capacity. Learning and Instruction, 17, 336-344.

Mahncke, H. W., Connor, B. B., Appelman, J., Ahsanuddin, O. N., Hardy, J. L., & Wood, R. A. (2006). Memory enhancement in healthy older adults using a brain plasticity-based training program: a randomized, controlled study. Proc. Natl. Acad. U.S.A, 103, 12523-12528.

Miyake, A., Friedman, N. P., Emerson, M. J., Witzki, A. H., Howerter, A., & Wager, T. D. (2000). The unity and diversity of executive functions and their contributions to complex “frontal lobe” tasks: A latent variable analysis. Cognitive Psychology, 41, 49-100.

Morrison, A. B. & Chein, J. M. (2010). Does working memory training work? The promise and challenges of enhancing cognition by training working memory. Springer, 18, 46-60. doi:10.3758/s13423-010-0034-0

Mozolic, J.L., Long, A.B., Morgan, A.R, Rawley-Payne, M., Laurienti, P. J. (2011). A cognitive training intervention improves modality-specific attention in a randomized controlled trial of healthy older adults. Neurobiol Aging, 32, 655-668.

Nouchi, R., Taki, Y., Takeuchi, H., Hashizume, H., Akitsuki, Y. (2012). Brain training game improves executive functions and processing speed in the elderly: A randomized controlled trial. PLoS ONE, 7(1), e29676. doi:10.1371/journal.pone.0029676

Oei, A. C. & Patterson, M. D. (2015). Enhancing perceptual and attentional skills requires common demands between the action video games and transfer tasks. Frontiers in Psychology, 6, 113. doi:10.3389/fpsyg.2015.00113

Park, D. C., Lautenschlager, G., Hedden, T., Davidson, N. S., & Smith, A. D. (2002). Models of visuospatial and verbal memory across the adult life span. Psychol. Aging, 17, 299-320.

Parsons,B., Magill, T., Boucher, A., Zhang, M., Zogbo, K., Bérubé, S., Scheffer, O., Beauregard, M., & Faubert, J. (2016). Enhancing cognitive function using perceptual-cognitive training. Clinical EEG and Neuroscience, 47(1), 37-47. doi:10.1177/1550059414563746

Rabipour, S. & Raz, A. (2012). Training the brain: Fact and fad in cognitive and behavioral remediation. Brain and Cognition, 79, 159-179. doi:10.1016/j.bandc.2012.02.006

Rosenthal, R. (1998). Meta-analysis: Concepts, corollaries and controversies. Advances in psychological science, 1, 371-384.

Sala, G. & Gobet, F. (2017). Does far transfer exist? Negative evidence from chess, music, and working memory training. Current Directions in Psychological Science, 26(6), 515–520. doi:10.1177/0963721417712760

Salthouse, T. A. (2004). What and when of cognitive aging. Curr. Dir. Psychol. Sci. 13, 140-144.

Schellenberg, E. G. (2006). Long-term positive associations between music lessons and IQ. Journal of Educational Psychology, 98, 457-468.

Shatil, E. (2013). Does combined cognitive training and physical activity training enhance cognitive abilities more than either one alone? A four-condition randomized controlled trial among healthy older adults. Frontiers in Aging Neuroscience, 5, 1-12. doi:10.3389/fnagi.2013.00008

Simons, D. J., Boot, W. R., Charness, N., Gathercole, S. E., Chabris, C. F., Hambrick, D. Z., & Stine-Morrow, E. A. L. (2016). Do “brain-training” programs work? Psychological Science in the Public Interest, 17, 103-186.

Smith, G. E., Housen, P., Yaffe, K., Ruff, R., Kennison, R. F., Mahncke, H. W., & Zelinski, E. M. (2009). A cognitive training program based on principles of brain plasticity: Results for the improvement in memory with plasticity-based adaptive cognitive training (IMPACT) study. Journal of the American Geriatrics Society, 57, 594-603.

Stine-Morrow, E. A. L., Hussey, E. K., & Ng, S. (2015). The potential for literacy to shape lifelong cognitive health. Policy Insights From the Behavioral and Brain Sciences, 2,

92-100. doi:10.1177/2372732215600889

Stocco, A., Yamasaki, B., Natalenko, R., & Prat, C. S. (2014). Bilingual brain training: A neurobiological framework of how bilingual experience improves executive function. International Journal of Bilingualism, 18(1), 67-92.

Thorndike, E. L. & Woodworth, R. S. (1901). The influence of improvement in one mental function upon the efficiency of other functions (I). Psychological Review, 8, 247-261.

Uchida, S., & Kawashima, R. (2008). Reading and solving arithmetic problems improves cognitive functions of normal aged people: a randomized controlled study. Age (Dordr), 30, 21-29.

van Heugten, C. M., Ponds, R. W. H. M., & Kessels, R. P.C. (2016). Brain training: Hype or hope? Neuropsychological Rehabilitation, 26, 639-644. doi:10.1080/09602011.2016.1186101

Verhaeghen, P., & Cerella, J. (2002). Aging, executive control, and attention: A review of meta- analyses. Neurosci. Biobehav. Rev. 26, 849-857.

Voss, M. W., Prakash, R.S., Erickson, K. I.,Basak,C.,Chaddock,L., & Kim, J.S. (2010). Plasticity of brain networks in a randomized intervention trial of exercise training in older adults. Front. Aging Neurosci, 2, 32. doi:10.3389/fnagi.2010.00032

Wilson, B. A. (1997). Cognitive rehabilitation: How it is and how it might be. Journal of the International Neuropsychological Society, 3, 487-496.