Short-Term & Working Memory

In our introductory article on memory, we talked about the different types of memories in brief. If you have not seen the introductory article on memory, you can find it here. In this article, we will be spending more time on the subject of limited capacity memory, working memory, and how information becomes stored in the brain.

Short-term memory as it’s name implies is a form of memory that lasts for a short time. To bring the time frame into perspective, we are talking about milliseconds to seconds. Without a reason to retain, information gathered from sensory perceptions fades almost as soon as we receive it. For example, the concept of stories on social media platforms harvests our short-term memories as we almost forget about the previous story while scrolling through the next one.

According to a Harvard psychologist named George Miller, short-term memory can hold up to seven units of information per time, and anything beyond that may get mixed up. In some ways, short-term memory might sound quite inefficient, but this is not the case. If the brain were to be able to process and store every bit of information that it were to be exposed to, this would lead to mental crowding and an ineffective memory retrieval process.

We are likely to depend on short-term memory when there are no preset cues both internally & externally to remind us. This necessitates the use of writing these things down for reference. We tend to form short-term memories of things that grab our attention and briefly rouses our emotions. This is why we could pass an obvious billboard on our way to work everyday, possibly notice that it’s there, but probably don’t know one word written on the sign itself. But if we were to narrowly escape an accident around that same point where the billboard is located, we’d have a more vivid short-term memory of the sign at that spot. If we rehearse the short-term memory of narrowly escaping a road traffic on accident near a yellow billboard on our way to work, then that memory gets moved over to long-term memory where it gets stored and can be retrieved.

Working memory is similar to short term memory but can pass as an intermediate memory system. While scientists are unsure of its classification, they however agree that working memory is what we rely upon when we need multiple pieces of information from both the short-term & long-term memory pools. To bring more clarity in the differences between the two, short-term memory holds data for a brief period of time while working memory uses the held data for task execution. Interestingly, the strength of one’s working memory is suspected to be directly linked to the level of their IQ. It is also generally accepted that how well the working memory performs depends on our ability to focus on what is important & tune out distractions.

So what happens when we need to hold more than a short string of information for a longer period? Two things; repetition & chunking. Repetition is rehearsing the information over and over again. Chunking is splitting large pieces of information into smaller groups that are easy to rehearse. For example, we use chunking when recalling phone numbers.