Sleep on it: making emotional memories last
Emotion-inducing events can form some of our most enduring memories, but how these memories become consolidated—particularly during sleep—is not well understood.
To answer this question, György Buzsaki and colleagues tracked the activity of cells in the hippocampus (representing location) and amygdala (representing emotion) while rats learned where a noxious puff of air would occur. During learning, some pairs of cells in the hippocampus and amygdala were active at the same time (“co-active”). During the sleep that followed learning, these co-activations grew stronger, signalling memory consolidation. Thus the endurance of emotional memories may be due, in part, to sleep-induced strengthening of communication between hippocampus and amygdala.
Girardeau et al. (2017) Reactivations of emotional memory in the hippocampus–amygdala system during sleep. Nature Neuroscience DOI: https://doi.org/10.1038/nn.463...
Making errors to improve learning
Nobody likes making mistakes, but it’s a great way to learn. Unfortunately, we seem to underestimate just how useful errors and corrective feedback can be.
According to researchers from University College London, this lack of understanding can lead learners to study in a suboptimal way. In this experiment, that meant spending more time reading test material, rather than being tested, making mistakes, and getting corrective feedback. Even straight after learning, subjects still judged reading to be the better strategy (it was actually worse).
Changing learner attitudes towards maligned but effective strategies, such as making mistakes and being corrected, is therefore important. As shown in this study, a good way to do this is by letting learners compare their own results as to which strategy works better; this proved more effective than simply telling them of the benefits of making mistakes.
Yang et al. (2017) Metacognitive unawareness of the errorful generation benefit and its effects on self-regulated learning. Journal of Experimental Psychology: Learning, Memory, and Cognition 43(7): 1073-1092. DOI: http://dx.doi.org/10.1037/xlm0000363
Brain signatures of different types of memory formation
Our knowledge base consists partly of memories from specific events, but also our own generalizations across multiple experiences. This means that when a new memory is formed, it must also integrate with – and perhaps update – our stored knowledge.
How does the brain achieve such specific and general memory formation at the same time? In this study, researchers show that two distinct brain mechanisms are involved. Using EEG to record brain activity while participants performed a memory test, the researchers showed that generalization performance could be predicted by brain oscillations in the theta frequency (4–6 Hz), but not by a different brain signature, the so-called late positive component of the EEG. This late positive component did, however, signal episodic memory performance. Thus two different neural mechanisms underlie specific and generalized memory formation.
Sans-Dublanc et al. (2017) Distinct neurophysiological mechanisms support the online formation of individual and across-episode memory representations. Cerebral Cortex 27(9):4314-4325. DOI: https://doi.org/10.1093/cercor/bhw231
Forgetting on purpose: Why some students want to actively forget course material
Students who experience stress when learning course material can, once the course finishes, be motivated to actively forget what they have learned. In this study, researchers from UCLA found that the amount of motivated forgetting depends on a student’s perception of their own ability.
For students in a university-level mathematics course, those who had the strongest self-belief in their ability had the highest level of motivated forgetting. In contrast, those with low self-belief showed no such behaviour. The authors suggest that this is because students whose experiences don’t align with their own expectations have their self-belief undermined, so leading them to suppress the stress-associated memories. Managing students’ expectations and emotional reactions to stress could therefore be important for how well they retain information in the long-term.
Ramirez et al. (2017) Classroom stress promotes motivated forgetting of mathematics knowledge. Journal of Educational Psychology 109(6): 812-825. DOI: http://dx.doi.org/10.1037/edu0...