Applications of the working memory model (Baddeley and Hitch, 1974)

Travis DixonCognitive Psychology

Theories and models in psychology can be evaluated based on their empirical evidence and their validity in explaining and predicting human behaviour. But they can also be judged on their productiveness – the extent to which they’ve inspired and provoked further research and applications in various fields. In this post, we’ll look at the various contributions the WMM has made with particular focus on educational psychology. 

The basic ideas of Baddeley and Hitch’s working memory model (the WMM) were proposed in 1974 and it’s been regularly updated ever since. To understand the contributions the model’s made to psychology, let’s first remember that Baddeley and Hitch’s model expanded Atkinson and Shiffrin’s idea of the short-term store by explaining the active processes involved in short-term memory and dividing the store into visual and verbal components. This elaboration is one of the major contributions of the WMM because it’s generated a wealth of research into factors that affect working/short-term memory and how this affects a range of behaviours.

Applications in Education

Numerous have been designed to measure an individual’s working memory capacity – the amount of information we can store and manipulate in our working memory. Measures of working memory capacity have since been linked with a range of outcomes, including learning, literacy, numeracy, reading comprehension, mathematical abilities, intelligence and general academic achievement. Further distinctions can be made by the type of working memory. For example, verbal working memory has been correlated with reading comprehension and literacy, whereas visual working memory capacity with mathematic achievement. Understanding the importance of working memory in learning has major applications in education. Here we’ll review three:

  • Computer game training
  • Listening to music
  • Media multi-tasking

Computer Game Training

If high working memory capacity can predict high achievement in academics, then low working memory capacity might be the reason why some students struggle in school. In order to test this, tools have been designed to accurately measure working memory capacity, like the Automated Working Memory Assessment. By using such tools, psychologists can help identify kids with working memory deficits. This can help explain why they struggle in school. It also allows the development of interventions and programmes aimed to improve kids’ working memory. The most prevalent of these in recent years has been the use of computer game training to improve working memory. A multi-billion dollar industry has been created with game designers claiming their products can improve working memory and reduce attentional problems in kids. Such claims do have support evidence. For instance, Klingberg et al. (2005) found that computer-based working memory training can improve working memory and reduce attentional problems. Other studies have found these changes may be because of neurological changes in the brain. However, Simons et al. (2016) and others have reviewed these studies and the general view is that while they can improve scores on specific working memory games, they have limited transfer to other areas (e.g. paying attention in class or improving reading comprehension).

Read more:

Computer games are just one factor of many that have been studied in relation to working memory.

Studying with Music 

Dual task studies have found that doing two tasks that use the same slave system reduces memory. So what about listening to music while you study? In 1993, Rauscher made a surprising discovery – when students listened to Mozart music for 10 minutes before performing IQ tests their scores on visuo-spatial tasks increased. This became known as the Mozart effect. But the findings were controversial because some studies replicated the findings while others didn’t. It caused heated debates and a plethora of studies – some even performed on rats! The current view is that if the Mozart effect is present it’s rather small, lasts a very short time (about 12 minutes) and is cause by improving someone’s mood and arousal, rather than the music itself.

If the effect is caused by changes to mood, does this mean listening to music you like improves learning? Well, it may depend on the type of music. This was tested by Perham and Currie in 2014.

Perham and Currie (2014) tested this in a repeated-measures experiment where students completed reading comprehension tasks while listening to either liked lyrical music, disliked lyrical music, instrumental music or nothing. Their test scores were best in the no-music condition, followed by instrumental. Their performance was the worst in the lyrical conditions, regardless if they liked the music or not and what’s more is that they accurately predicted these results. In other words, they knew the lyrical music would be distracting and hinder their performance.

There are two possible explanations for these results. One is that the background lyrics get mixed up with the information being processed in the articulatory loop. This reduces the ability to remember what’s just been read. Another possible explanation is that the music distracts the central executive making it less effective at controlling the articulatory loop. The central executive could block out the distracting music, but this requires cognitive energy which could also reduce focus on reading task.

Based on the functions of the articulatory loop and the limited capacity of the phonological store, it makes sense that lyrical music would decrease memory compared to non-lyrical music. This is similar to studies on the irrelevant sound effect that show irrelevant, background phonological sounds (any sound relating to language) have direct access to the phonological loop and so disrupt the information in the articulatory loop that we’re trying to comprehend and learn.

This study is about reading comprehension. What about listening comprehension? This brings us to another important application of WMM ideas – media-multi-tasking.

Media Multi-tasking

Multi-tasking means performing two tasks at once. We’ve seen in dual task studies that this is incredibly difficult and results in reduced performance because it taxes our working memory capacity. Many people erroneously believe that multi-tasking makes them more productive. In fact, the opposite is true. In education, this is becoming increasingly important as smartphones and laptops in the classroom become increasingly ubiquitous. It has caused many teachers and parents to worry that the constant source of distractions and attention being divided across multiple devises is reducing the attention span of kids today. Not surprisingly this has also sparked a lot of research.

Cain et al., 2016 conducted a study to see if there was a correlation between use of media (TV, smartphones, etc.) and working memory capacity. Seventy-four eighth graders from Boston, U.S.A. participated in the study and data was gathered on their media use through questionnaires. The amount of time using media was correlated with the students’ test scores of their working memory capacity (e.g. n-back and digit span tasks, activities that require remembering sequences of numbers). The results showed a statistically significant (yet moderate) negative correlation between working memory capacity and media usage, with a -0.27 for digit span tasks and -0.38 for n-back tasks. This study suggests using technology may reduce working memory capacity.

This study shows how multi-tasking across multiple devices could have a negative impact on working memory. Based on other research we know the dangers this might bring.

You might argue, though, that this study is correlational and correlation doesn’t mean causation. Plenty of other experimental studies have shown similar detrimental effects on multi-tasking on working memory and learning.

Kuznekoff and Titsworth (2013) conducted a study to see how texting during a lecture would affect learning. The researchers got 54 American college students to watch a 12 minute video lecture about communication theories and told them to take notes as they normally would in class. After viewing the video they were given three minutes to review and then two tests: a multiple choice test and a free recall test. But there were three different conditions – a high distraction group, a low distraction group and a control (no distraction) group. Students in the distraction groups used their mobile phones to access a web-page that sent them messages to respond to (e.g. “What’s your favourite restaurant?” or “Comment on this photo.”). This was designed to resemble a conversation someone might have on Facebook messenger during class. Messages were sent every 60 seconds in the high-distraction group and every 30 seconds in the low-distraction group. The control condition scored 66% on the multiple choice quiz, compared to 60% and 52% for the low and high-distraction groups, respectively. The control condition also wrote 62% more in their notes and scored higher in the free recall test than the low and high distraction groups (36% and 51%, respectively).

The two possible explanations for these results are consistent with those on music: (a) texting could reduce memory because it detracts our attention and (b) it disrupts information processing in the phonological loop. In the distraction conditions, students wrote less and left out more key details. This is evidence for the aforementioned diverted-attention hypothesis. But analysis of their notes showed they were also more likely to write inaccurate or unclear notes of key details. This means they were paying attention as they did write the notes, but because they got details wrong it suggests “…texting/posting must also impact how students process information after the information has passed through their attention filters.” In terms of working memory, the researchers conclude that “…not only is attention diminished, but the act of processing information in working memory could also be compromised.” (Kuznekoffand Titsworth, 2013)

This study shows the valuable contributions Baddeley and Hitch’s model has made to educational psychology despite the model being proposed decades before the invention of mobile phones and social media. The breaking-down of working memory into the attentional control centre of the central executive and the slave systems that process information has enabled psychologists to study and explain modern phenomena, like the influence of digital technology on learning and memory.

My mantra is “Do the thing you’re doing!”

Other Applications

But the applications of the WMM stretch beyond just academic achievement and education. It has been used to understand ADHD, PTSD and even paleoanthropology where scientists have suggested working memory might have been the difference between Neanderthals and homo sapiens. Working memory deficits have also been used to test for early detection of Alzheimer’s disease. Baddeley believes these applications are due to the simplicity of the model and the development of basic experimental procedures like dual task studies that have been developed to test it. (Baddeley, 2012).

References

Gathercole, S. E., & Alloway, T. P. (2006). Practitioner Review: Short-term and working memory impairments in neurodevelopmental disorders: diagnosis and remedial support. Journal of Child Psychology and Psychiatry, 47(1), 4–15. doi:10.1111/j.1469-7610.2005.01446.x

Colmar, S., & Double, K. (2017). Working Memory Interventions With Children: Classrooms or Computers? Journal of Psychologists and Counsellors in Schools, 27(02), 264–277. doi:10.1017/jgc.2017.11

Pickering, S. J., Gathercole, S. E., & Peaker, S. M. (1998). Verbal visuospatial short-term memory in children: Evidence for common and distinct mechanisms. Memory & Cognition, 26(6), 1117–1130. https://doi.org/10.3758/BF03201189

Perham, N., & Currie, H. (2014). Does listening to preferred music improve reading comprehension performance? Applied Cognitive Psychology, 28(2), 279–284. doi:10.1002/acp.2994