REM sleep and memory consolidation

 An interesting lecture given by Dr. Gabriela Torres Platas discussed her findings on two-way communication during REM sleep. Before her presentation, we read the article “Real-time dialogue between experimenters and dreamers during REM sleep,” written by Karen R. Konkoly et al., which explored an individual’s ability to perceive external stimuli during REM sleep without waking up. Using eye movements (left-right patterns) and facial muscle contractions, the researchers found that individuals asleep were able to compute simple answers, maintain information in working memory, and express replies to yes or no questions, mathematical problems, and auditory cues. The researchers concluded that two-way communication with dreamers is possible during REM sleep, opening new approaches for research in memory and future studies on dream modifications. This led me to explore further other topics that discussed learning in REM sleep and memory retrieval. An article I found aims to investigate how sleep can affect the memorization of fear extinction in people with chronic sleep disturbance.  

 

In the article “Fear extinction memory is negatively associated with REM sleep in insomnia disorder,” written by Ryan Bottary et al., the authors observe the impact of chronic poor sleep following fear conditioning and extinction learning on memory consolidation. The authors focus on individuals with Insomnia Disorder (ID) to view how it influences fear extinction, and how it can influence memory consolidation compared to individuals with no chronic sleep disorder. The participants did two sessions to measure fear conditioning, extinction learning, and recall. In the first session, participants experienced fear conditioning and extinction learning. Fear conditioning was paired with a neutral stimulus and a shock, causing the neutral stimulus to create a fear response. In the second session, participants were re-exposed to the conditioned stimuli without shock. The researchers used skin-conductance responses (SCR) to record conditioning, extinction, and recall, measuring physiological fear learning and memory. Overall, the researchers found that individuals with ID are more likely to favor fear memory retention over emotional “safety” memory retention. 

 

Both articles demonstrated the importance of REM sleep in memory consolidation. This research, among others, is vital to finding solutions for individuals with PTSD and other anxiety-like disorders. As we see in the article by Ryan Bottary and others, people with PTSD are more likely to retain fear memory over safety memory, influencing extinction learning and recall. From Dr. Plata’s presentation, we learned that two-way communication is possible with individuals during REM sleep, vital for future research in memory modification. Overall, the importance of memory consolidation in REM sleep is vital for future research to aid individuals with PTSD and other anxiety-like disorders. It is interesting to see what individuals could do during REM sleep and how these findings are used to explain memory retrieval and pave future research in memory modifications. 

 

References:

 

Bottary, R., Seo, J., Daffre, C., Gazecki, S., Moore, K. N., Kopotiyenko, K., Dominguez, J. P., Gannon, K., Lasko, N. B., Roth, B., Milad, M. R., & Pace-Schott, E. F. (2020). Fear extinction memory is negatively associated with REM sleep in insomnia disorder. Sleep, 43(7). https://doi.org/10.1093/sleep/zsaa007  

 

Konkoly, K. R., Appel, K., Chabani, E., Mangiaruga, A., Gott, J., Mallett, R., Caughran, B., Witkowski, S., Whitmore, N. W., Mazurek, C. Y., Berent, J. B., Weber, F. D., Türker, B., Leu-Semenescu, S., Maranci, J., Pipa, G., Arnulf, I., Oudiette, D., Dresler, M., & Paller, K. A. (2021). Real-time dialogue between experimenters and dreamers during REM sleep. Current Biology, 31(7). https://doi.org/10.1016/j.cub.2021.01.026