How Stress Can Change Your Brain: An Animated Introduction

We hear the mantra of “self-care” in ever-widen­ing cir­cles, a con­cept both derid­ed and cel­e­brat­ed as a “mil­len­ni­al obses­sion,” with the acknowledgment—at least in this NPR think piece— that self-care was cen­tral to the philoso­phies of antiq­ui­ty, from Aris­to­tle to the Sto­ics.

In phi­los­o­phy, self-care exists as a set of ethics. The rea­sons for this may often be couched in high-mind­ed dis­cus­sions of civics, sex­u­al pol­i­tics, and exis­ten­tial self-actu­al­iza­tion. These days, doc­tors and researchers are mak­ing urgent appeals for our men­tal and phys­i­cal health, and the sci­ence of stress is an unsur­pris­ing­ly rich field of inves­ti­ga­tion at the moment.

It’s hard to over­state the neg­a­tive effects of stress on the body over time. Increased stress hor­mones have been linked in study after study to overeat­ing and obe­si­ty, low­ered immune response, drug use and addic­tion, mem­o­ry impair­ment, heart dis­ease, and many oth­er debil­i­tat­ing and life-threat­en­ing con­di­tions. “The long-term acti­va­tion of the stress-response sys­tem,” writes the Mayo Clin­ic, “and the sub­se­quent over­ex­po­sure to cor­ti­sol and oth­er stress hormones—can dis­rupt almost all your body’s process­es.” (The video below makes this har­row­ing point with some help­ful, ani­mat­ed com­ic relief.)

When we expe­ri­ence chron­ic stress, it rais­es our blood pres­sure and affects our car­dio­vas­cu­lar sys­tem, increas­ing the chances of heart attack or stroke. The even worse news—reports the TED-Ed video at the top of the post—is that chron­ic stress weak­ens our abil­i­ty to make sound deci­sions about our well-being, by chang­ing the size, struc­ture, and func­tion of our brain.

We’re famil­iar with the symp­toms of chron­ic stress: “sleep­ing rest­less­ly,” becom­ing “irri­ta­ble or moody,” “for­get­ting lit­tle things,” and “feel­ing over­whelmed and iso­lat­ed.” Con­tin­u­ous stress, from our work lives, home lives, social and polit­i­cal lives, can cause shrink­ing in parts of the brain respon­si­ble for mem­o­ry, spa­tial recog­ni­tion… and stress reg­u­la­tion.

Research shows that high lev­els of cor­ti­sol and oth­er stress hor­mones can cause shrink­ing of the pre­frontal cor­tex, the part of the brain respon­si­ble for rea­son­ing and deci­sion-mak­ing. Stress can inhib­it neuroplasticity—the abil­i­ty of the brain to adapt to new circumstances—and neu­ro­ge­n­e­sis: the abil­i­ty to pro­duce new brain cells.

Con­verse­ly, stress increas­es the size of the amyg­dala, which acti­vates fight-or-flight respons­es, which in turn increase the strain on our heart and blood ves­sels.

All of these effects can set the stage in lat­er life for major depres­sion, forms of cog­ni­tive decline and demen­tia, and Alzheimer’s dis­ease.

Most unset­tling­ly, as the video notes, these effects can be passed down to the next gen­er­a­tion, fur­ther­ing the cycle of chron­ic stress in our chil­dren and theirs. Per­sis­tent stress “fil­ters down” to DNA, mak­ing it genet­i­cal­ly inher­i­ta­ble.

Giv­en the incred­i­ble amount of stress most peo­ple seem to be under, this sci­ence can seem like a diag­no­sis of doom. We all know that chron­ic stres­sors assail us all day long, with­out ask­ing whether we want them in our lives or not. An increas­ing amount of our dai­ly stress, I’d hypoth­e­size, may indeed come from the grow­ing real­iza­tion of how lit­tle con­trol we have over many stress­ful sit­u­a­tions.

But the TED explain­er ends with good news, and it’s been there all along—we can find it in the ancient Greeks, in Bud­dhist prac­tices, and many oth­er tra­di­tions, both active and con­tem­pla­tive. We can con­trol our respons­es to stress, and thus reverse and mod­u­late the effects of cor­ti­sol on our sys­tem. The best, proven, ways to do so are through exer­cise and med­i­ta­tion (and, I’d add, good nutri­tion).

These activ­i­ties will not erad­i­cate the con­di­tions of inequal­i­ty, injus­tice, or insta­bil­i­ty that stress us all out—a great many of us more than oth­ers. But prac­tic­ing “self-care” inas­much as we are able with stress-reliev­ing dis­ci­plines and prac­tices will bet­ter equip us to respond to the state of the world and the state of our lives by inter­rupt­ing the bio­log­i­cal mech­a­nisms that, over time, make things much worse. Find some help­ful resources below.

Relat­ed Con­tent:

Stream 18 Hours of Free Guid­ed Med­i­ta­tions

Med­i­ta­tion 101: A Short, Ani­mat­ed Beginner’s Guide

Philoso­pher Sam Har­ris Leads You Through a 26-Minute Guid­ed Med­i­ta­tion

How to Get Start­ed with Yoga: Free Yoga Lessons on YouTube

Do Your­self a Favor and Watch Stress: Por­trait of a Killer (with Stan­ford Biol­o­gist Robert Sapol­sky)

How Mind­ful­ness Makes Us Hap­pi­er & Bet­ter Able to Meet Life’s Chal­lenges: Two Ani­mat­ed Primers Explain

How Bak­ing, Cook­ing & Oth­er Dai­ly Activ­i­ties Help Pro­mote Hap­pi­ness and Alle­vi­ate Depres­sion and Anx­i­ety

Allen Gins­berg Teach­es You How to Med­i­tate with a Rock Song Fea­tur­ing Bob Dylan on Bass

Josh Jones is a writer and musi­cian based in Durham, NC. Fol­low him at @jdmagness