Ons werkgeheugen is beperkt. We kunnen slechts een korte tijd een kleine hoeveelheid informatie opslaan. Eerst dacht men aan 7 getallen, vandaag hoor je eerder 3-4 stukken van informatie. Een telefoonnummer (voor de mobiele telefoons) zou dan al in feite te lang zijn, daarom dat we er ‘chunks’ van maakten om het zo toch te kunnen hanteren.

Nieuw onderzoek door onderzoekers aan Carnegie Mellon University toont dat bij die ‘chunks’, samengeperste informatie, herkenbaarheid ook een belangrijke rol speelt. Geake omschreef in 2009 het werkgeheugen al als een soort van spamfilter, waarbij gecontroleerd werd of wat je van prikkels binnenkrijgt overeenkomt of aansluit bij kennis die je al hebt. Dit nieuwe onderzoek bevestigt dit, maar geeft aan dat dit zelfs ook speelt voor kleinere hoeveelheden informatie. Daarom is het moeilijker voor Amerikanen om IAJ, FKI, RSU en SAF te onthouden dan lettercombinaties zoals FBI, CIA, JFK, IRS of USA.

Nog belangrijker: de onderzoekers vermoeden op basis van hun studie dat ons werkgeheugen wellicht meer aankan dan we voorheen dachten, als de informatiestukken, de chunks, die we gebruiken maar al voor ons herkenbaar waren:

“We are suggesting that working memory capacity is not a fixed quantity but interacts with the familiarity of the elements that need to be processed. If everything is very familiar, it is easy to comprehend and build new knowledge. If all of the components are unfamiliar, the task becomes very difficult or impossible,” (bron)

Meer informatie over het verloop van het onderzoek:

For the study, 20 CMU undergraduates with no prior experience with Chinese language learning were familiarized with 64 Chinese characters during three-hour-long sessions each week for one month. This involved searching for a particular character in visual display of similar characters. Half of the characters were randomly selected to display at a higher frequency — 20 times more often — to become more familiar to the participants, leaving the remaining “low-frequency” characters less familiar.

Each week, participants also completed a memory test requiring them to learn an association between a pair of characters and an arbitrary English word. Each pair of characters was completely new and was composed either of the low-frequency or the high-frequency characters. The researchers found that novel combinations of characters that were made from the more familiar characters were easier to learn to associate with new information than combinations made from the less familiar characters.

Reder and her team theorized that learning would be faster and more accurate with more familiar characters because, according to them, stronger chunks consume less working memory and working memory is critical for forming new knowledge. To further support the finding that more familiar chunks consume less working memory resources, they had participants complete a popular test of working-memory (N-back) with both the high- and low-frequency characters and found that the N-back task was much easier with the high-frequency characters.

“This work has implications for how to optimize instruction, specifically that concepts should be introduced to students in a way that they have a good grasp and familiarity with those concepts before trying to combine them into more complex informational structures. These findings may also help to explain certain paradoxes such as why children tend to learn computer applications more easily than adults and may help to explain why they learn second languages better than adults,” Reder said.

“Little kids may actually have more working memory than adults. They often appear to have less only because they have fewer knowledge chunks and those chunks are weaker than adults. Adults have wisdom ‘knowledge and skills — and scientists have been confusing that with greater working memory,” she said.

Abstract van de studie:

Despite vast efforts to better understand human learning, some principles have been overlooked; specifically, that less familiar stimuli are more difficult to combine to create new knowledge and that this is because less familiar stimuli consume more working memory resources. Participants previously unfamiliar with Chinese characters were trained to discriminate visually similar characters during a visual search task over the course of a month, during which half of the characters appeared much more frequently. Ability to form associations involving these characters was tested via cued recall for novel associations consisting of two Chinese characters and an English word. Each week performance improved on the cued-recall task. Crucially, however, even though all Chinese character pairs were novel each week, those pairs consisting of more familiar characters were more easily learned. Performance on a working-memory task was better for more familiar stimuli, consistent with the claim that familiar stimuli consume fewer working memory resources. These findings have implications for optimal instruction, including second language learning.