YOU MAY have heard recently that neuroscientists reported regularly playing the game Tetris is good for the brain because it increases gray matter in the cortex, the part associated with thinking.

Maybe you?ve had the Tetris theme song running through your head ever since you found out. Maybe you can also visualize the ever-increasing group of Russian dancers and musicians that appear at the end of the B game (yes, I was a Tetris Gameboy addict), though before the rocket ship finally blasts off.

Comments from the study?s senior author Rex Jung, who is affiliated with both the Mind Research Network and its neighbor the University of New Mexico, suggest the study was inspired in part by research on another repeated and mentally stimulating activity: juggling.

Jung noted that over time a thicker cortex could result from an active brain engaged in keeping all the balls moving. A thicker cortex leads to increased thought-processing capacity, which in turn means more mental productivity.

?We did our Tetris study to see if mental practice increased cortical thickness, a sign of more gray matter,? he said in a statement. ?More gray matter in an area could mean that the area would not need to work as hard during Tetris play.?

To answer the question of the computer game?s ability to increase gray matter in the brain, Jung and his colleagues recruited 26 girls between the ages of 12 and 15 who didn?t play computer games such as Tetris on a regular basis for their three month-long study, dividing them into two groups.

One group played Tetris for at least an hour and a half every week on a website monitored by the researchers, but the other group was not allowed to play it at all during the same time period. The girls? brains were scanned to record the activity noted before and after the experiment. Each girl?s brain was also scanned to see how brain activity differed when each one was playing the game.

How Tetris is played

If you?ve never played Tetris before, picture an empty screen that has a few lines at the bottom formed from four-block configurations that form a square, a straight line, an ?L? shape, a ?T? shape, and a ?Z? shape. More of these same four-block shapes fall from the top of the screen and the game?s objective is to simply rotate and move the blocks to fill the spaces at the bottom of the screen and get rid of all the lines before the screen fills up with unused shapes.

The researchers found that the gray matter did thicken in the brains of the Tetris-playing girls compared to the control group. Study co-author Richard Haier from the University of California at Irvine, a consultant for the company that exclusively oversees the licensing and development of all Tetris products, attributed the change to the mental and physical stimulation offered by the game.

?Tetris, for the brain, is quite complex,? Haier said in a statement. ?It requires many cognitive processes like attention, hand/eye coordination, memory and visual spatial problem solving all working together very quickly. It?s not surprising that we see changes throughout the brain.?

The researchers noted that the regions where the cortex had thickened weren?t the same places where brain activity had decreased due to increased processing capacity resulting from the game. Structural change doesn?t always lead to functional change in the same place, they observed in their report, adding that further exploring these differences is on their agenda.

The findings raise the question of what long-term players? cortices might look like under similar scans. Given that the game has been around for 25 years, perhaps the researchers will one day look at how long-term players? brains might have been changed by constant play.

The study by Jung and his colleagues was published online September 1 in the journal BMC Research Notes.

E-mail the author at massie@massie.com.