Mental training affects distribution of limited brain resources

"Attentional-blink" occurs when two pieces of information are presented to a person in very close succession, and the brain doesn't perceive the second piece of information because it is still processing the first. Richard Davidson and colleagues attempted to determine if intensive mental training through meditation could extend the brain's limits on information processing, reducing "attentional-blink."

The researchers compared two groups of people--17 expert meditators and 23 novices--to see if either was better at recognizing two pieces of information shown in quick succession.

The participants were tested at the beginning and end of a 3-month period. For the intervening 3 months, the meditation practitioners participated in a retreat, during which they meditated for 10-12 hours a day. The novices participated in a 1-hour meditation class, and were asked to meditate for 20 minutes a day for the week before each test.

The researchers found that intensive training did reduce "attentional-blink." The participants who had gone through the mental training were more likely to perceive both pieces of information instead of just the first because the brain used fewer resources to detect the first piece of information -- leaving more resources available to detect the second. The researchers also note that this study supports the idea that brain plasticity, or the ability of the brain to adapt, exists throughout life.

==== pubmed entry:

The information processing capacity of the human mind is limited, as is evidenced by the so-called "attentional-blink" deficit: When two targets (T1 and T2) embedded in a rapid stream of events are presented in close temporal proximity, the second target is often not seen. This deficit is believed to result from competition between the two targets for limited attentional resources. Here we show, using performance in an attentional-blink task and scalp-recorded brain potentials, that meditation, or mental training, affects the distribution of limited brain resources. Three months of intensive mental training resulted in a smaller attentional blink and reduced brain-resource allocation to the first target, as reflected by a smaller T1-elicited P3b, a brain-potential index of resource allocation. Furthermore, those individuals that showed the largest decrease in brain-resource allocation to T1 generally showed the greatest reduction in attentional-blink size. These observations provide novel support for the view that the ability to accurately identify T2 depends upon the efficient deployment of resources to T1. The results also demonstrate that mental training can result in increased control over the distribution of limited brain resources. Our study supports the idea that plasticity in brain and mental function exists throughout life and illustrates the usefulness of systematic mental training in the study of the human mind.
PMID: 17488185