When you hear the words Brown-Peterson you may think of a law firm. Turns out it’s a cool exercise to test memory.
Want to learn more about it and give it a shot? Read on for details.
What Is Memory?
Have you ever tried to remember a phone number for take out? Or remember a algebraic formula for a test? Both of these are examples of working memory, or how we hold on to and process new and old information. We use working memory for a lot of reasons, like learning, understanding, analyzing or building new memories.Psychologists like to study how memory works. Two experiments were conducted to test memory.
One was by John Brown in 1958 and another by Lloyd and Margaret Peterson in 1959, hence the name Brown-Peterson. Both memory tasks were mostly the same and yielded similar results. Want to see how it works?
What Is the Brown-Peterson Task?
Both Brown and the Petersons created their experiment to test memory, specifically the impact that using strategies, such as rehearsal, has. You’ve probably used rehearsal before, like when you’re trying to remember a phone number, and you repeat it in your head or out loud several times. The studies that Brown and the Peterson team conducted showed that the ability to recall decreased if a person wasn’t allowed to use rehearsal. Here’s how it worked.
Participants in the study were given a trigram, or sequence of three letters, such as UKQ or JKW. They were then given a distractor task, or an event meant to focus their attention elsewhere so they didn’t remember the trigram using strategies like mental rehearsal. Participants were asked to count backwards by threes or fours, starting at a large 3-digit number. Test organizers stopped the participants at between three and 18 seconds, referred to as a recall interval, to see if they could remember the trigram.The researchers found the longer they let participants count, or in other words distracted them, the less likely they were to recall the number.You try it. In a second, look at your trigram, then away from the screen and count backwards by three starting with the number 566.
Set a timer for fifteen seconds; when the time is up, see if you can remember the trigram. Ready? Your trigram is KPE. Go!How’d you do? We used a high time interval, so don’t worry if you didn’t remember your trigram. Human memory isn’t wired to keep information long term unless we work at it.
Let’s take a closer look at this thing called rehearsal.
We talked earlier about rehearsal, or the mental process of repeating to increase short term memory. The Brown-Peterson Task is based on preventing rehearsal. When you use rehearsal you’re focusing your mind on what you want to remember – like repeating a phone number or a new acquaintance’s name. We categorize rehearsal in two ways:
When you use that repetitive process we talked about before, like repeating a phone number, you’re using maintenance rehearsal. You can either verbalize or think about what you’re trying to remember. Scientists have studied memory and found out it can hold information for about 20 seconds.
Using maintenance rehearsal can increase that time to about 30 seconds.
Unlike maintenance rehearsal, elaborative rehearsal uses the meaning of the word to help recall. This works well with vocabulary words, such as botany.
Looking up the definition of the word, studying pictures and examples, or reading about the practice can all help increase the chances of remembering.
Brown-Peterson Task Details
The above Brown-Peterson task was a brief rundown of the experiment. Here are some important details to keep in mind.
- Unlike our little experiment above, all communication was verbal. The researchers gave the trigram verbally, not in writing.
- The participants were given a light signal to alert them to stop counting backwards and repeat the trigram.
- Participants were each tested eight times for 3, 6, 9, 12 or 15 second intervals.
- Each trigram was used an equal amount of times for each participant; additionally, the experiments were equally split by counting by threes or fours.
- Trigrams never repeated the same letter twice in a row.
- Participants were given exactly 15 seconds between the end of one task and the start of the next.
- Finally, to be sure the pace of the trial was constant, researchers and participants used a metronome, or device that marks time, with a 120 BPM (beat per minute) and told to follow the rhythm of two letters or number spoken per second.
Memory can be tricky, and there’s still much scientists don’t know. However, Brown and the Petersons have helped make great strides in understanding how rehearsal impacts short term memory.
Two separate, yet similar, research studies were conducted in the 1950s – one by John Brown and the other by husband and wife team Lloyd and Margaret Peterson. These studies found that when rehearsal is prevented from being used, short term memory is decreased. Researchers gave participants a trigram, or three letter sequences, to remember, then prevented them from using rehearsal techniques by having them count backwards.
They found that the more time that they allowed to count, the less participants recalled.We look at rehearsal in two ways – maintenance and elaborate rehearsal. Just as the words imply, maintenance rehearsal is repeating what you want to remember to increase recall. Elaborate rehearsal requires you to be more active, finding the definition and using that information to help remember meanings of words.