University of Tübingen Sleep + N-Back Study : Dec 2017/Jan 2018
Sleep has been known for a while to be important in consolidating memories and
motor skills. It's also a period where more neurogenesis (the birth of new brain cells in adulthood (ref).
In this latest Neurobiology of Learning and
Memory publication, researchers at University of Tübingen wanted to know whether sleep might help synergistically with the working memory gains from n-back training demonstrated in the John Hopkins' study (preprint here). Their research studied both adults and children. It compared working
memory gains after only a short amount of n-back training (just 3 sessions) in two conditions: (1) where training was followed by a night's sleep (training in the evening); (2) where training was followed by a day awake (training in the morning).
The data revealed the following:
>
Overnight sleep facilitates training-based improvements in working memory (maximum n-back performance).
> Both adults and children profit from sleep in these ways.
The researchers conclude:
Overall these findings do not only indicate that working memory performance is subject to plastic changes but also that sleep is a brain state that can be exploited to enhance such changes.
And:
if sleep follows the training of working memory, afterwards the brain is able to operate on longer event sequences, than after post-training wakefulness.
When to Train?
This latest study tells us when training is optimal: In the late evening, 1-2 hours before a good night's sleep!
Johns Hopkins showed us that working memory could improve substantially (30% in their study) from n-back training. Most of those training in that study trained during the day, not just before sleep in late evening. So we would expect even greater IQ gains from training before sleep.
N-Back Meta-Studies - Bringing It All
Together
This most recent study adds to the message the last 33 published, randomized, active-controlled dual n-back studies tell us: there are real training effects of DNB brain training on IQ (particularly working memory) - beyond placebo effects and just getting good at the n-back game itself through practice (review 1, review 2). There has been controversy concerning far transfer to fluid reasoning ability (also known as Gf) from dual n-back training, but this controversy does not cloud results showing
far transfer to working memory (also known as Gwm) - another key subfactor of general intelligence (G), and a better predictor of many real life IQ-demanding outcomes such as academic success.
And this very recent recent study adds to the message of the multiple brain imaging studies (Ref 1, Ref 2, Ref 3) showing neuroplasticity change in the the fronto-parietal network (FPN). This is the brain’s ‘control hub’ and is also called the ‘executive control network’. It sends out top down signals for current task goals and
exerts control by flexibly biasing information flow across multiple large-scale functional networks. The FPN is a key network underlying intelligent, goal directed action and learning.