Have you paid any mind to the growing popularity of mindfulness? It seems everywhere I look there is a new promotion or app touting the benefits of this meditative practice. But what exactly is mindfulness and how might it benefit us?

Mindfulness is a state of being that is characterized by a nonreactive awareness of current surroundings, actions, and thoughts. Put simply, mindfulness is about accepting the present moment as is. By being in the present moment, obtrusive thoughts can be avoided. Though there are many forms of mindfulness training, including a series of short, meditation exercises. In these exercises, people are instructed to let their minds wander for a few minutes before being told to reel their minds back to the present moment.

Research suggests that mindfulness can reduce stress, enhance general well-being, and even improve the healing process. (Challenges in this line of research and the conclusions have been discussed.) Mindfulness may be beneficial for cognition too. Research suggests that mindfulness may improve the ability to detect an unexpected distractor in a change-blindness task, increase recall, and recognition memory. (Yet, other research has found that mindfulness leads to greater susceptibility to false memories.)

If mindfulness does improve learning and memory, how might it work? It seems reasonable to assume that mindfulness might free up cognitive resources necessary for peak learning and memory performance. Some argue these additional resources are reallocated to increasing attentional capabilities. According to this view, mindfulness helps to keep you focused on the task which in turn benefits learning and memory.

Another view is that mindfulness improves processes central to learning and memory without altering attention. These central processes include the encoding of information (i.e., encoding processes), the storage of information into long-term memory (i.e., consolidation processes), and the retrieval of that information from long-term memory during a subsequent memory test (i.e., retrieval processes).

Which view is correct? Adam Lueke and Niloufar Lueke (pictured below) investigated this question by conducting two experiments that were described in a recent paper in the Psychonomic Society’s journal Memory & Cognition. Their main hypothesis was that mindfulness helps free up cognitive resources that specifically enhance the encoding of information without affecting attentional capabilities.

To test this hypothesis, the researchers used standardized memory tests, including the Rey Auditory Verbal Learning Test (RAVLT) and the Item-Specific Deficit Approach (ISDA). The RAVLT is a series of memory tests where participants first listen to and recall the same list of words over five consecutive learning trials. Then participants study a new list of words, which acts as interference for the original list. A free recall test of the original list is administered immediately after studying this new list of words as well as after a 20-minute delay (i.e., two delayed free recall tests). Participants finally take a recognition test of the original list.

The ISDA is used in conjunction with the RAVLT to separately measure encoding, consolidation, and retrieval processes, the processes involved in memory, by providing indices for each process. The indices are:

• The encoding index, which is determined by the number of studied words that were not recalled on at least three of the five learning trials. If a studied word is only recalled once or twice during the learning trials, that counts as an encoding failure because those words were not encoded successfully.
• The consolidation index, which is determined by counting the number of studied words that were recalled during the learning trials but not recalled on either of the two delayed free recall trials. This pattern would suggest that the words were encoded because they were successfully recalled during the initial learning trials but not consolidated because they were not recalled after a delay.
• The retrieval index, which is determined by counting the number of words recalled during the learning trials but were inconsistently recalled on the two delayed free recall trials. This pattern would suggest a retrieval failure. These words were consistently recalled during the learning trials (i.e., encoded) and were recalled successfully on one of the delayed free recall trials (i.e., consolidated), but participants failed to recall these items on both of the delayed free recall trials (i.e., a retrieval failure).

To measure attention, Lueke and Lueke used the Color-Word Interference Test (CWIT), which is an extension of the classic Stroop procedure. The CWIT generally measures how well participants selectively attend to task-relevant stimuli.

In Experiment 1, participants were randomly assigned to either take part in a 10-minute mindfulness training session (the experimental condition) or listen to a 10-minute audiotape (the control condition) before completing the CWIT and then the RAVLT. The results of Experiment 1 are shown below.

Those assigned to the mindfulness training outperformed those assigned to the control condition in every single RAVLT trial. This result is consistent with previous research that has shown a marked improvement in memory performance following a brief mindfulness training.

And, by using the ISDA, Lueke and Lueke found that the participants in the mindfulness condition had fewer encoding failures compared to controls, but an equivalent amount of consolidation and retrieval failures. Further, both groups of participants performed equally on the CWIT. Together, these results suggest that mindfulness did not improve attentional capabilities but did improve the encoding process.

Lueke and Lueke next manipulated the time during which the mindfulness training took place. If mindfulness training selectively boosts encoding, then performance should not be improved when taking the training after the learning trials. In Experiment 2, participants either took part in mindfulness training (the experimental condition) or listened to an audiotape (the control condition) following the learning trials but before the delayed free recall trials of the RAVLT.

If performance still improves for those in the mindfulness condition, then mindfulness might boost consolidation or retrieval processes in addition to the encoding process. Consistent with their main hypothesis, mindfulness did not boost memory performance in Experiment 2. Furthermore, mindfulness training did not affect attentional capabilities as measured by the CWIT (a replication of Experiment 1).

Together these results suggest mindfulness training selectively boosts encoding rather than attentional capabilities. More broadly, this research suggests that a simple, cost-effective strategy to improve learning and memory is to take part in a brief mindfulness training. Importantly, that training should be done prior to learning. This training could also be beneficial to those with attention deficits. Lueke and Lueke found that mindfulness training improved performance “across the board” from those with low attention capabilities to those with high attention capabilities.

Regarding the growing popularity of mindfulness, if these effects are generalizable, then the ~8% of Americans and others who meditate should have a nice boost in memory.

Psychonomics article featured in this post:

Lueke, A., & Lueke, N. (2019). Mindfulness improves verbal learning and memory through enhanced encoding. Memory & Cognition, 47(8), 1531-1545. doi:10.3758/s13421-019-00947-z