You may have heard that the brain is plas­tic.

As you well know. the brain is not made of plastic…Neuroplasticity, or brain plas­tic­i­ty, refers to the brain’s abil­i­ty to CHANGE through­out life.

The human brain has the amaz­ing abil­i­ty to reor­ga­nize itself by form­ing new con­nec­tions between brain cells (neu­rons).

In addi­tion to genet­ic fac­tors, the envi­ron­ment in which a per­son lives, as well as the actions of each per­son, play a sig­nif­i­cant role in plas­tic­i­ty.

Neu­ro­plas­tic­i­ty occurs in the brain…

1- At the begin­ning of life: when the imma­ture brain orga­nizes itself.

2- In case of brain injury: to com­pen­sate for lost func­tions or max­i­mize remain­ing func­tions.

3- Through adult­hood: when­ev­er some­thing new is learned and mem­o­rized

Plas­tic­i­ty, learn­ing and mem­o­ry

For a long time, it was believed that as we aged, the con­nec­tions in the brain became fixed, and then sim­ply fad­ed. Research has shown that in fact the brain nev­er stops chang­ing through learn­ing. Plas­tic­i­ty is the capac­i­ty of the brain to change with learn­ing.

Changes asso­ci­at­ed with learn­ing occur most­ly at the lev­el of con­nec­tions between neu­rons: New con­nec­tions form and the inter­nal struc­ture of the exist­ing synaps­es change. Did you know that when you become an expert in a spe­cif­ic domain, the areas in your brain that deal with this type of skill will grow?

For instance, Lon­don taxi dri­vers have a larg­er hip­pocam­pus (in the pos­te­ri­or region) than Lon­don bus dri­vers. Why is that? It is because this region of the hip­pocam­pus is spe­cial­ized in acquir­ing and using com­plex spa­tial infor­ma­tion in order to nav­i­gate effi­cient­ly. Taxi dri­vers have to nav­i­gate around Lon­don where­as bus dri­vers fol­low a lim­it­ed set of routes.

Plas­tic­i­ty can also be observed in the brains of bilin­guals. It looks like learn­ing a sec­ond lan­guage is pos­si­ble through func­tion­al changes in the brain: the left infe­ri­or pari­etal cor­tex is larg­er in bilin­gual brains than in mono­lin­gual brains.

Plas­tic changes also occur in musi­cians brains com­pared to non-musi­cians. Gas­er and Schlaug com­pared pro­fes­sion­al musi­cians (who prac­tice at least 1hour per day) to ama­teur musi­cians and non-musi­cians. They found that gray mat­ter (cor­tex) vol­ume was high­est in pro­fes­sion­al musi­cians, inter­me­di­ate in ama­teur musi­cians, and low­est in non-musi­cians in sev­er­al brain areas involved in play­ing music: motor regions, ante­ri­or supe­ri­or pari­etal areas and infe­ri­or tem­po­ral areas.

Final­ly, Dra­gan­s­ki and col­leagues recent­ly showed that exten­sive learn­ing of abstract infor­ma­tion can also trig­ger some plas­tic changes in the brain. They imaged the brains of Ger­man med­ical stu­dents 3 months before their med­ical exam and right after the exam and com­pared them to brains of stu­dents who were not study­ing for exam at this time. Med­ical stu­dents’ brains showed learn­ing-induced changes in regions of the pari­etal cor­tex as well as in the pos­te­ri­or hip­pocam­pus. These regions of the brains are known to be involved in mem­o­ry retrieval and learn­ing.

Plas­tic­i­ty and brain injury

A sur­pris­ing con­se­quence of neu­ro­plas­tic­i­ty is the fact that the brain activ­i­ty asso­ci­at­ed with a giv­en func­tion can actu­al­ly move to a dif­fer­ent loca­tion as a con­se­quence of expe­ri­ence or brain dam­age.

In his book “The Brain That Changes Itself: Sto­ries of Per­son­al Tri­umph from the Fron­tiers of Brain Sci­ence,” Nor­man Doidge describes numer­ous exam­ples of func­tion­al shifts. In one of them, a sur­geon in his 50s suf­fers a stroke. His left arm is par­a­lyzed. Dur­ing his reha­bil­i­ta­tion, his good arm and hand are immo­bi­lized, and he is set to clean­ing tables. The task is at first impos­si­ble. Then slow­ly the bad arm remem­bers how too move. He learns to write again, to play ten­nis again: the func­tions of the brain areas killed in the stroke have trans­ferred them­selves to healthy regions!

The brain com­pen­sates for dam­age by reor­ga­niz­ing and form­ing new con­nec­tions between intact neu­rons. In order to recon­nect, the neu­rons need to be stim­u­lat­ed through activ­i­ty.

Final­ly, let me address a cou­ple of ques­tions we often get…

Can new neu­rons grow in my brain?

Yes, and regard­less of how young or old you are. Here’s a good arti­cle.

Can you rec­om­mend a good book to learn more about neu­ro­plas­tic­i­ty and how to har­ness it for good?

Indeed. We pub­lished The Sharp­Brains Guide to Brain Fit­ness: How to Opti­mize Brain Health and Per­for­mance at Any Age pre­cise­ly to pro­vide a use­ful entry point into all this research and how to apply it. And we’re hap­py to report that it’s get­ting rave reviews!