Practice Makes Perfect... Until it Doesn't

It is by now common knowledge among scientists that the brain has a certain plasticity – we are able to change and/or strengthen neural connections based on different mental, physical, musical, or other exercises. This has spawned a huge desire and demand for memory-enhancing exercises, and brain teasers, directed at increasing your level of cognitive functioning. A study published recently in Nature, however, has refuted this idea and claimed that brain teasers and memory exercises actually have little to no effect at all on total cognition.

The study was conducted on over 11,000 participants, separated into three different experimental groups (one being the control). Although all participants experienced a slight increase in performance on the tests, this was chalked up to practice effects since the control group also performed better. Some of the largest critiques on the study so far, according to an article found in Time Magazine, is that the study was not conducted in a controlled environment (participants did the mental exercises on their computers at home, with no oversight), and that the amount of mental exercises they were asked to do were not sufficient to increase cognitive capacity. Because this study challenges previously popular beliefs, I expect that there will be a lot of debate within the cognitive community regarding it.

At first glance, this study seems to contradict the common saying “practice makes perfect” – one of Gary Marcus’ favorite sayings in his book Guitar Zero. Even though he by no means concludes that through practice anyone can achieve perfection (there must also exist a certain aptitude for the skill/task), everyone can – according to Marcus – achieve at the very least mediocrity. The authors of the study, however, do agree with Marcus on this. Practice in a particular mental task will vastly increase performance of that task. Their argument is that practice will not increase general, or overall, cognition.

This I think ties into another of Marcus’ main points: many tasks and exercises that we, as humans, perform, involve multiple areas of the brain – they are not localized. While I understand Marcus’ point in this regard, and it is obviously backed up with neuroimaging scans. However, this study seems to be arguing for localization in terms of cognition. Although brain scans were not used, results indicated that overall cognition did not improve, only performance in the specific task did. Following this line of thinking, only synapses (regardless of whether or not they are localized to a specific part of the brain) that were involved in the initial task would be strengthened – there is no total strengthening.

Though several prominent neuroscientists have already spoken out against this study, it is not actually as contradictory to already-held beliefs as it first seems. The main purpose of the study seems to have been directed at attacking the multi-million dollar companies that have profited off of advertising better memory and cognition. Though the ‘practice makes perfect’ adage can still be upheld in this study, the question is now – if we truly do want to increase our cognitive capacity – how can we practice with the whole brain?

http://www.time.com/time/health/article/0,8599,1983306,00.html

Owen, A. M. et al. Nature advance online publicationdoi:10.1038/nature09042 (20 April 2010).