Toxic.
Justice.
Misinformation.
These three words garnered much attention in 2018. For example, there was a 45% increase in the number of times that the word “toxic” was looked up and a 75% increase in the number of times that the word “justice” was looked up on online dictionaries. The increase in interest in these words were part of the reasons they were selected as the word of the year by Oxford Dictionary, Merriam-Webster, and Dictionary.com, respectively.
Let’s put that aside for now.
Next, take a moment to think about an event from anytime in your life. We’ll get back to that later too.
How memories activate other memories is an issue that has been of interest to researchers for decades. This is known as priming and occurs as responses to stimuli are affected by prior exposure to other stimuli. There are many types of priming, including semantic priming, conceptual priming, perceptual priming, repetition priming, masked priming, and autobiographical priming. (See Hal Pashler’s 2018 keynote address at the Psychonomic Society 59th Annual Meeting where he discussed reproducibility issues with social priming experiments.)
In semantic priming tasks, participants are faster to recognize or produce words that are semantically related than words that are unrelated. You are faster processing ‘butter’ if it was preceded by ‘bread’ rather than ‘aardvark’. In autobiographical priming tasks, participants who remember life events from a particular time, for example during elementary school, will remember more events from that time, rather than other stages of their life, when later asked to remember events from any time period.
The two forms of priming can also operate together: The semantic-autobiographical priming hypothesis holds that semantic memories prime autobiographical memories. This hypothesis was tested by John Mace, Megan McQueen, Kamille Hayslett, Bobbie Jo Staley, and Talia Welch, and the findings were reported in a recent article published in in the Psychonomic Society’s journal Memory & Cognition.
In three experiments, participants were assigned to a priming group or a control group. Those in the priming group were exposed to prime words and those in the control group were not. All participants were then asked to recall personal experiences. The number of items and events recalled from life experiences that were related to the prime words were counted and compared across groups. Before we turn to the results, we need to sort out a few methodological details and differences between the three experiments.
The semantic priming task
In all of the experiments, as shown in the figure below, participants in the priming group rated the familiarity of high vs. low frequency words on a scale from 0-5 (0 = unknown; 5 = highly familiar).
It could be the case that the semantic primes did not directly activate autobiographical memories because it is possible that participants in the priming group probed autobiographical memories to rate the familiarity of the words in the priming task. This would mean that autobiographical memories, not semantic primes, activated related autobiographical memories.
To address this possibility, in Experiment 3, there was a third group (a second priming group) where the participants took part in a lexical decision task. Instead of rating words on familiarity, participants were presented with a list of words and non-words and decided if each item was a word or non-word. This priming task is less likely to elicit the retrieval of autobiographical memories.
The autobiographical task
In Experiments 1 and 3, the autobiographical memory task was voluntary. Participants were given cue words and asked to write about a personal experience related to that word.
In Experiment 2, the autobiographical memory task was involuntary. As shown in the figure below, participants were presented with hundreds of slides of horizonal lines and many fewer slides of vertical lines. Each slide had a statement in the middle, some of which contained a prime word for those in the priming group. Participants were to ignore the words and to respond by saying “yes” aloud every time a slide with vertical lines appeared. During this task, participants were encouraged to record any memories that came to mind.
The researchers measured the overlap between the semantic priming content that was presented and the content of the autobiographical memories that were later retrieved. For example, a participant in the priming group may have been primed with the word “pet” and then during the autobiographical task, she was given the word “friend.” She may have written about the times she and her childhood friends would play in the woods with her dog. The mention of her dog and the prime word “pet” would count as overlap. If those in the priming group had more overlap than those in the control group, then that would be support for the semantic-autobiographical priming hypothesis.
That is exactly what Mace and colleagues found. In all experiments, the priming groups had more overlap than the control group, irrespective of whether the autobiographical memory task was voluntary or involuntary, and whether the priming task was a familiarity rating task or a lexical decision task.
The table below shows the mean percent of content that overlapped between primes and autobiographical memories. In each experiment, the priming group had greater overlap than the control groups: 11% more in Experiment 1, 20% more in Experiment 2, and 10% more in Experiment 3 (averaged across priming groups).
The results from these experiments provide support for the semantic-autobiographical priming hypothesis. In all of the experiments, semantic words primed the content of autobiographical memories that later came to mind. The authors raised the thought-provoking possibility that “…involuntary remembering is not functional to everyday cognition, as these memories are merely a consequence of semantic-autobiographical priming.”
Let’s get back to the memory you thought of when first reading this post. Any chance it had to do with one of the 2018 words of the year? Based on the results of Mace and colleagues, commonly used words such as these, may bring to mind related autobiographical memories. This may make you want to be exposed more to positive words than to negative words such as “toxic” or “misinformation”.
For that reason, I’ll leave you with these words…
Laughter.
Justice.
Psychonomics article focused on in this post:
Mace, J. H., McQueen, M. L., Hayslett, K. E., Staley, B. J. A., & Welch, T. J. (2019). Semantic memories prime autobiographical memories: General implications and implications for everyday autobiographical remembering. Memory & Cognition, 47, 299-312. DOI: 10.3758/s13421-018-0866-9.
