Mighty Dons Of Science News

A wom­an looks fa­mil­iar, but you can’t re­mem­ber her name or where you met her. New re­search sug­gests the mem­o­ry ex­ists – you simp­ly can’t re­trieve it.

Us­ing brain im­ag­ing, neu­ro­sci­en­tists at the Uni­vers­ity of Cal­i­for­nia, Ir­vine found that a per­son’s brain ac­tiv­ity while re­mem­bering an event is very si­m­i­lar to when it was first ex­pe­ri­enced, even if spe­cif­ics can’t be re­called.

“If the de­tails are still there, hope­ful­ly we can find a way to ac­cess them,” said Jeff John­son, a post­doc­tor­al re­searcher at the uni­ver­sity and lead au­thor of the stu­dy, ap­pear­ing Sept. 10 in the sci­ent­ific jour­nal  Neu­ron.

“By un­der­stand­ing how this works in young, healthy adults, we can po­ten­tial ly gain in­sight in­to situ­a­t­ions where our mem­o­ries fail more no­tice­ably, such as when we get old­er,” he said. “It al­so might shed light on the fate of viv­id mem­o­ries of trau­mat­ic events that we may want to for­get.”

John­son and col­leagues used func­tion­al mag­net­ic res­o­nance im­ag­ing, a brain scan­ning tech­nique, to study the brain ac­tiv­ity of stu­dents.

The stu­dents were shown words and asked to per­form var­i­ous tasks: im­ag­ine how an art­ist would draw the ob­ject named by the word, think about how the ob­ject is used, or pro­nounce the word back­ward in their minds. The scan­ner cap­tured im­ages of their brain ac­tiv­ity dur­ing these ex­er­cises.

About 20 min­utes lat­er, the stu­dents viewed the words a sec­ond time and were asked to re­mem­ber any de­tails linked to them. Again, brain ac­tiv­ity was recorded.

Uti­liz­ing a math­e­mat­i­cal meth­od called pat­tern anal­y­sis, the sci­en­tists as­so­ci­at­ed the dif­fer­ent tasks with dis­tinct pat­terns of brain ac­tiv­ity. When a stu­dent had a strong rec­ol­lec­tion of a word from a par­tic­u­lar task, the pat­tern was very si­m­i­lar to the one gen­er­at­ed dur­ing the task. When rec­ol­lec­tion was weak or non­ex­ist­ent, the pat­tern was not as prom­i­nent but still rec­og­niz­a­ble as be­long­ing to that par­tic­u­lar task, the re­search­ers said.

“The pat­tern an­a­lyz­er could ac­cu­rate­ly iden­ti­fy tasks based on the pat­terns gen­er­at­ed, re­gard­less of wheth­er the sub­ject re­mem­bered spe­cif­ic de­tails,” John­son said. “This tells us the brain knew some­thing about what had oc­curred, even though the sub­ject was not aware of the in­form­at­ion.”