Dual n-back training: potential tool for lucid dreamers
A couple years back I became interested in dual n-back (DNB) training: a game designed to challenge its player's working memory. Later I became interested in lucid dreaming. The more I read about both topics, the more I began to make a link between the two. In fact, when I searched for "n-back" on Dreamviews, I was actually surprised to find out that DNB has yet to have been discussed here!
In short, the game flashes a series of sounds and pictures on the screen, which the user must memorize. In 1-back mode, a player needs to recall what happened one instance ago. Once you get good at that, the game increases in difficulty by asking you to recall what happened two instances ago (2-back), and so on. It's incredibly challenging. Anyway, the idea is that since this training does such a good job at activating the parts of the brain associated with working memory, perhaps it would do well to increase one's IQ (something generally considered to be set in stone). There's been at least one study so far that has made the correlation between DNB training and IQ improvement (which admittedly has been subject to criticism). That's interesting, but more interesting to me is the implications it has on lucid dreaming. If you're interested in learning more about general DNB stuff, gwern.net hosts a very thorough FAQ on dual n-back training. You can also find a pretty decent online DNB community at the relevant Google Groups page. The Brain Workshop seems to be their preferred DNB game. I also found a decent version for my iPhone called "iBrain."
Now that you have an idea what DNB is about, let's talk about how it relates to our passion: lucid dreaming. While I was reading through Gwern's DNB FAQ, I kept noticing "dream recall" popping up in the testimonials. Note that these guys aren't in it for dreaming: DNB is about intelligence training. Dream recall seems to be an often-cited side-effect of the training:
Quote:
Originally Posted by negatron
One perhaps coincidental thing I noticed is that dream recollection went up substantially.
Quote:
Originally Posted by Ashirgo
I have also experienced better dream recalling, with all these reveries and other hallucinations included ;)"
Quote:
Originally Posted by Jan Pouchlı
Better dream recall.
Quote:
Originally Posted by TeCNoYoTTa
I also want to report that after training on DNB I found that I am dreaming almost every day...by the way I remember that this effect was not directly after training...unfortunately I stopped using DNB from about 2 months or something like that and now I dream less.
Quote:
Originally Posted by Chris
One thing I have noticed is the recollection of a number of very unpleasant images in dreams. Specifically, images of bodily disease, mutilation, injury and post-mortem decomposition. I find it difficult to believe it's just a coincidence, because I can't remember when I last had such a dream, and I've had maybe half a dozen since I started dual n-back. But perhaps it's simply owing to better recall.
Quote:
Originally Posted by reece
Dream recall has increased significantly as has lucid dreaming.
Naturally, I became interested in learning more about the relationship between DNB, working memory, and dream recall. The obvious explanation is that since a user is exercising recall during DNB, that ability transfers over to dream recall. Since I consider dream recall my number one goal as an aspiring oneironaut, this is more than enough motivation for me to start a daily regimen of DNB training.
But perhaps DNB can help lucid dreaming in a way more directly than just by increasing dream recall. I became suspicious of this after learning what areas of the brain DNB activates.
Quote:
Originally Posted by Working memory capacity and its relation to general intelligence
More importantly, significant correlations were observed between RAPM [Raven's Progressive Matrices, a non-verbal intelligence test], n-back [a superset of DNB], and activity in DLPFC [dorsolateral prefrontal cortex] and ACC [anterior cingulate cortex]. In fact, the correlation between RAPM and event-related activity to lure trials [a tricky n-back] was particularly striking (r ¼ 0.54) and remained significant even when performance on non-lure trials was partialled out. Finally, the correlation between lure performance and RAPM was almost completely accounted for by lure-trial activity in DLPFC. That is, the percent-signal-change in DLPFC associated with lure trials accounted for 92% of the covariance between lure performance and RAPM, suggesting that the WMC/executive attention/g relation is mediated by activity in DLPFC.
[Link]
By the way, a "'lure trial' is "basically B-R-B-A in a 3-back session. Here the second b "lures the mind" since it's almost 3-back and therefore takes alot of executive control not to press the L button." - Pontus
Quote:
Originally Posted by Does excessive memory load attenuate activation in the prefrontal cortex? Load-dependent processing in single and dual tasks: functional magnetic resonance imaging study
When subjects perform single tasks as well as dual tasks at different levels of difficulty, comparable activation patterns for both conditions seem to emerge in the DLPFC, indicating that both single and dual tasks enhance activation with increasing load in that region.
[Link]
Quote:
Originally Posted by The Psychophysiology of Lucid Dreaming (by Stephen LaBerge)
To summarize, an elevated level of CNS activation seems to be a necessary condition for the occurrence of lucid dreams. Evidently the high level of cognitive function involved in lucid dreaming requires a correspondingly high level of neuronal activation. In terms of Antrobus's (1986) adaptation of Anderson's (1983) ACT* model of cognition to dreaming, working memory capacity is proportional to cognitive activation, which in turn is proportional to cortical activation. Becoming lucid requires an adequate level of working memory to activate the pre-sleep intention to recognize that one is dreaming.This level of cortical and cognitive activation is apparently not always available during sleep, but normally only during phasic REM.
[Link]
Okay, so isn't it interesting that n-back training does so well at activating the dorsolateral prefrontal cortex (DLPFC)! A couple years ago, Dreamviews user I H8 Reality pointed out one hypothesis which links the DLPFC to lucid dreaming:
Quote:
Originally Posted by I H8 Reality
According to Allan Hobson the differences between the self-awareness, working memory and executive functions, and consciousness experienced in waking life and its loss in dreaming can be explained by deactivation of the dorsolateral prefrontal cortex during REM sleep (The Prefrontal Cortex in Sleep, 2002).
The Dorsolateral Prefrontal Cortex (DLPFC) is responsible for executive functions and working memory. As a consequence of deactivation of the DLPFC during sleep, executive functions such as self-consciousness and analytical thought are severely impaired during dreams. (The Prefrontal Cortex in Sleep, 2002).
In his book The Dream Drugstore(2001-pg 97) Allan Hobson proposed that lucid dreaming is the result of DLPFC activation during REM sleep, and that working memory resides in the DLPFC which is deactivated during sleep and results in the bizarreness and mute executive functions associated with dreams.
I really wish there was an fMRI study out there which looked at the DLPFC during a lucid dream. Until then, Allan Hobsin's speculation is the best I can do. So under that hypothesis, in addition to improved dream recall, perhaps DNB training will improve one's ability to become lucid by way of strengthening the DLPFC.
But that's not the only part of the brain that n-back training activates that has interesting implications...
Quote:
Originally Posted by Differential dorsolateral prefrontal cortex activation during a verbal n-back task according to sensory modality
Functional neuroimaging studies carried out on healthy volunteers while performing different n-back tasks have shown a common pattern of bilateral frontoparietal activation, especially of the dorsolateral prefrontal cortex (DLPFC). Our objective was to use functional magnetic resonance imaging (fMRI) to compare the pattern of brain activation while performing two similar n-back tasks which differed in their presentation modality. Thirteen healthy volunteers completed a verbal 2-back task presenting auditory stimuli, and a similar 2-back task presenting visual stimuli. A conjunction analysis showed bilateral activation of frontoparietal areas including the DLPFC. The left DLPFC and the superior temporal gyrus showed a greater activation in the auditory than in the visual condition, whereas posterior brain regions and the anterior cingulate showed a greater activation during the visual than during the auditory task. Thus, brain areas involved in the visual and auditory versions of the n-back task showed an important overlap between them, reflecting the supramodal characteristics of working memory. However, the differences found between the two modalities should be considered in order to select the most appropriate task for future clinical studies.
[link]
Interesting stuff! While n-back training activates many other areas besides the DLPFC, two parts that are especially interesting are the anterior cingulate cortex (ACC) and the superior temporal gyrus (STG). Here's why:
Quote:
Originally Posted by What Dreams Are Made Of NEW TECHNOLOGY IS HELPING BRAIN SCIENTISTS UNRAVEL THE MYSTERIES OF THE NIGHT. THEIR WORK COULD SHOW US ALL HOW TO MAKE THE MOST OF OUR TIME IN BED
Another active part of the brain in REM sleep is the anterior cingulate cortex, which detects discrepancies. Eric Nofzinger, director of the Sleep Neuroimaging Program at the University of Pittsburgh Medical Center, thinks that could be why people often figure out thorny problems in their dreams. "It's as if the brain surveys the internal milieu and tries to figure out what it should be doing, and whether our actions conflict with who we are," he says.
[link]
Quote:
Originally Posted by Dreaming and the brain: from phenomenology to neurophysiology
Some lesions, especially those in medial prefrontal cortex, the anterior cingulate cortex and the basal forebrain, are associated with increased frequency and vividness of dreams and their intrusion into waking life.
[link]
Quote:
Originally Posted by Visualizing Out-of-Body Experience in the Brain
Two patients have been described in whom out-of-body experiences were evoked by electrical stimulation of the right temporoparietal junction. The patient described by Penfield had a floating feeling without autoscopy, induced by electrical stimulation of the posterior part of the superior temporal gyrus, anterior to the angular gyrus.
[link]
Perhaps, then, DNB might help us by way of activating the ACC, which apparently facilitates problem solving and conflict resolution while dreaming as well as it having to do with dreaming frequency and vividness. It's also very interesting that the STG (another DNB-activated area), through electrical stimulation, can induce out-of-body experiences.
I, personally, prefer to stay practical. I speculate that DNB may improve dream frequency, lucidity, and vividness by way of the DLPFC, ACC, and STG, but that's really just speculation (and not even very good speculation: I'm "carwashguy," not "neuroscientistguy"). After all, there's controversy about whether or not DNB training even improves working memory in the first place. That said, the main thing prompting me to practice DNB daily is the anecdotal evidence of dream recall improvement. But really, only time will tell if DNB will help even that.
