In Part One of this series, I detailed the Testing Effect and argued that students should frequently and objectively test their knowledge and analytic abilities. I also noted that faculty should support these efforts by guiding students towards quality materials and away from inferior ones. In Part Two, I discussed metacognition and self-regulated learning and contended that schools seeking higher bar pass rates should move away from controlling students’ learning processes and instead train students to monitor their own comprehension and abilities.
In this post, I’ll examine spaced repetition, the idea that revisiting information at specified intervals solidifies memory and ultimately drastically increases knowledge and understanding.
More after the jump….
Spaced repetition is the simple fact that learning is enhanced when information is distributed over time instead of learned in a “massed” (or crammed) fashion. This phenomenon is one of the most consistently replicated effects in experimental psychology, and a robust literature exists confirming the effect in many different contexts. It works like this: If students learn a concept on September 14th and ignore that concept until just a week before their exam on December 2nd, that approach constitutes massed practice and is dramatically inferior to interleaving multiple retrievals at certain specific intervals.
The neuroscience behind this effect is instructive. Neurogenesis is the generation of neurons over time in the areas of the brain involved in learning. Between the neurons are spaces called synapses, whose job is to communicate between neurons. This is the basis of memory. If unused, synaptic connections weaken. But if more learning occurs, the strength of the signal (called synaptic plasticity) returns.
The speed with which the neural networks deteriorate is deemed the “forgetting curve.” The following figures demonstrate that curve:
These figures should frighten students (and when I present this material in class, it often elicits a gasp) because they mirror the way most law students approach learning. They walk out of a class on res ipsa loquitur and “feel” like they get it; that might be true or might be untrue. But, assuming that it is true, students often ignore that material for the next two months and review it again just a few weeks before exams. Given what we know about the forgetting effect, you can see that even with the cramming that occurs before exams (Fig. 2), the memory does not return to optimal levels.
This figure shows how spaced repetition could allow students to walk into the exam with far more knowledge:
By spacing repetitive memory interventions, the learner essentially keeps the neurons, and the synaptic signals between them, alive by repeatedly activating them. Note, however, that the learner shouldn’t review the material at regular intervals. The figure above shows that the first interval is shorter than the second, which is shorter than the third, etc. It turns out that as the neurons are reactivated and the synapses again carry signals to each other, they increase their durability and need less frequent stimulation until they begin to decline again; this is known as “the lag effect.” Also, materials that the learner knows well require less review than the materials students know less well, thus allowing yet more spacing. These two features – longer intervals and prioritizing less well-known material – make the spaced repetition process more efficient than otherwise would be the case.
I should address one counterargument. I would imagine that some would claim that exam success – and building lawyerly competence – is not about the rote memorization of information. Legal concepts are sometimes indeterminate and are therefore different from more determinate materials, like anatomy or (non-theoretical) mathematics. Success on exams is also based on analytical skills and issue spotting. Given that, spaced repetition becomes irrelevant.
I would rebut this argument in several ways. First, comprehension, issue spotting, and analysis are predicated upon knowing doctrine. You can’t thoroughly understand FRE 801 if you don’t remember what that rule says or what the Committee Notes state. You can’t spot a specific Confrontation Clause issue if the brain has not encoded the “primary purpose” rule. You can’t argue for your client that FRE 403 prohibits otherwise relevant evidence if you don’t remember that unfair prejudice (et al) must substantially outweigh probativeness.
Second, we know that spaced repetition not only positively impacts memory, but also aids understanding. Learning occurs not through some literal recording mechanism but instead by the relationship between the meaning of one bit of information to the meaning of and associations with preexisting knowledge. Therefore, comprehension of the second matter is contingent upon the memory and meaning of the preexisting knowledge. This notion touches upon the concept of “cognitive schema,” which I’ll explain in my next post.
Lastly, my claim isn't that spaced repetition is the only method of study. To develop comprehension and analytical skills, students also should (among other things) take practice exams, complete "issue spotter drills," and understand the analyses used in the cases they read.
The implications of spaced repetition for pedagogical change are substantial. As I’ve noted before, however, the purpose of my series is not to discuss how faculty can change their classrooms but instead to discuss how students can change their learning. (I will address specific study techniques – for this and the other topics covered in this series – in my final post). In short, spaced repetition, a mostly ignored technique, could enhance students’ performance both in law school and the bar exam.