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Happy St. Patrick’s Day! For this week’s topic, we’re covering time. Specifically, we’re asking:

  • Does the amount of time between learning materials impact memory?
  • How do non-standard days/times impact motivation?

Spaced Training

Did I use this opportunity to throw in a Doctor Who GIF? Absolutely. But we’re not actually talking about that kind of space… more so about the “time” kind of space… Which really still sounds like Doctor Who. Well, allons-y!

One of the most consistent findings in learning deals with retention - specifically, forgetting happens quite quickly. Back in the 1800s, Hermann Ebbinghaus discovered that forgetting occurs rapidly, within the first 24 hours of learning, and then levels out. This is called the “forgetting curve.” Ebbinhaus’ findings have since been replicated time and time again, consistently illustrating this drop in new information. So, how do we keep that new information we just learned?

The “spacing effect” tells us that creating a system where we learn material over spaced intervals, rather than a “massed” time, leads to higher recall, recognition, and overall memory. The spacing effect is also commonly referred to as “distributed practice,” which we’re huge fans of and cover quite a bit (see LSW Issues 43 & 54)! While the effects of distributed practice have been replicated many times, the researchers on this study wanted to find the optimal interval lengths (Kornmeier, Sosic-Vasic, & Joos, 2022).

In this research paradigm, native German speakers were tasked with learning Japanese vocabulary words. Learners engaged with 5 learning blocks during a “Learning Period.” Each learning block, remember: 5 of these, had a “Study Phase” and “Test Phase” as well. During the learning blocks, learners were provided with German-Japanese vocabulary pairs to learn and then tested on those words. The total “Learning Period” was then followed up with a “Final Test Period.” TL;DR - Learners had 5 sessions of studying/testing, then two final exams. Learners were split into groups that differed in their spacing intervals between learning blocks. Groups were as follows: 7.5 minute, 4 hours, 8 hours, 12 hours, and 24 hours. Finally, all learners completed two final tests, “one 24 h and another one 7 days after the last learning period” (Kornmeier et al., 2022).

Which group forgot the most words? In the 24 hour final test, almost no forgetting occurred for learners with “spacing intervals of either 4, 8, or 13 h[ours],” while the 7.5 minute learners forgot almost 10% of what they learned (Kornmeier et al., 2022). The one week final test did show forgetting across all groups. However, again, the 7.5 minute learners showed the highest amount with over 30% of words forgotten; all other groups combined showed an average of 12% of forgetting (Kornmeier et al., 2022). Overall, this study illustrates that spaced learning continues to be best. Specifically, if the retention interval needed is short (i.e., a day or two), then a spacing interval between 4 to 12 hours is ideal. If we want to learn long-term, then longer spacing intervals (up to 24 hours) are better (Kornmeier et al., 2022).

The authors point out that a 12 hour interval seems to work best with our circadian rhythm, but ultimately recommend any interval between 4 and 24 hours, pending how many “learning blocks” need to be completed in a day and individual preferences (Kornemeier et al., 2022).

Key Takeaway: Spacing learning materials is crucial for long-term memory. When learning information, it is best to learn small amounts that are spaced out by at least 4 to 24 hours. Spaced learning promotes better retention of information over a massed learning approach, or over smaller spaced intervals (i.e., less than an hour).

Read More (Open): Kornmeier, J., Sosic-Vasic, Z., & Joos, E. (2022). Spacing learning units affects both learning and forgetting. Trends in Neuroscience and Education, 26.

It’s St. Patrick’s Day! (How’s your motivation?)

From Kormeier et al. (2022), we know that there should be time between what we learn. Recent research from Giurge and Woolley (2022) also suggests that when we’re working affects our motivation. When we focus on learning, intrinsic motivation (covered back in LSW Issue #4) is a crucial component to consider. While external motivation (i.e., badges, leaderboards, gamification, rewards, etc.) are helpful, we generally want learners to, well, want to learn. One aspect of intrinsic motivation that has gotten somewhat tricky as we educate employees and students is when we are doing the teaching/learning; this timing aspect is particularly potent in the virtual age. So, when should we have people working on learning?

The researchers on this paper conducted a series of 6 studies to evaluate how employees' intrinsic motivation was affected by working either standard (Monday-Friday, 9-to-5) or non-standard (weekends/holidays) work times (Giurge & Woolley, 2022). Through these studies, both academic and work pursuits were evaluated.

In one study, university students found studying in the library on a federal holiday, but not university holiday, were surveyed. Researchers then made half of the students aware of the federal holiday, changing their perception of the day to a non-standard work day, while the other half were not told. Students told about the holiday, and thus had a non-standard notion, reported lower intrinsic motivation than the standard students (Giurge & Woolley, 2022).

Another study assessed employee motivation to work on a standard Monday vs. a Monday that is a holiday. One important difference here is that employees were not explicitly told about the holiday, rather it was simply displayed on the calendar (see image).

(Giurge & Woolley, 2022)

When comparing motivation on these work days, employees reported lower intrinsic motivation “when working during federal holiday versus a regular work day” (Giurge & Woolley, 2022).

The researchers also evaluated counterfactual thinking, which in this scenario would look something like “If I wasn’t working on this holiday, I could be… playing dolls with my son, organizing the garage, hanging out with my friends, etc.” As expected, when engaging in counterfactual thinking, intrinsic motivation decreased (Giurge & Woolley, 2022). However, the researchers also evaluated an intervention technique, which consisted of making counterfactual thoughts less accessible. The results showed that when people were engaged in thinking that was unrelated to counterfactuals, intrinsic motivation actually increased. Further, it even improved work persistence (Giurge & Woolley, 2022). Something that I found particularly compelling about this last piece is that the participants were university students working during their Spring Break, which qualitatively made the results *that much more robust* for me.

Overall, intrinsic motivation does seem to decrease when working or studying during non-standard times. So, if possible, create a learning environment that takes time of day (or day of the week/year) into consideration. When learning or work must take place during non-standard days/times, implement other types of thinking to combat counterfactual thoughts.

Key Takeaway: Working or learning during non-standard times negatively affects intrinsic motivation. Encourage employees to learn or work during standard times, if possible. For those working or learning in non-standard times, fostering connections with others working during that time may decrease counterfactual thoughts and increase motivation.

Read More ($): Giurge, L M., & Woolley, K. (2022). Working during non-standard work time undermines intrinsic motivation. Organizational Behavior and Human Decision Processes, 170.

Pets of Learning Science Weekly

This week’s floof is brought to us by reader Carmen M.! And, I must say, I am truly obsessed with this handsome traveler!

“Wilbur is a six year old poodle-mutt rescue. He's an avid hiker with a record of 22 miles in one day! He can also now say that he's an international traveler as he went to Italy with his parents for four months (his first ever airplane ride).”✈️

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The LSW Crew

Learning Science Weekly is written and edited by Katie Erhardt, Ph.D.

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