Reading habits and emotional vocabulary

Reading increases vocabulary and helps us to communicate better, but also has less well-known benefits. For example, some studies have shown that reading fiction improves our ability to empathise. One theory for this effect on empathy is that when exposed to emotionally relevant words, we develop a more nuanced understanding of emotions, making us more self-aware and better able to regulate our emotions.

In this study of adolescent students, the authors found that time spent reading was correlated with the number of emotionally positive (e.g. happy, excited) and emotionally negative words (e.g. sad, anxious) the students could list, and that females outperformed males. According to the authors, these findings support the idea that reading improves emotional self-awareness and regulation by enhancing emotional vocabulary.

Dylman et al. (2020) Reading habits and emotional vocabulary in adolescents. Educational Psychology 40(6): 681-694 DOI: https://doi.org/10.1080/01443410.2020.1732874

Memory consolidation not just about neurons

Memory consolidation converts newly acquired information into long-term memories, a process that involves dialog between the hippocampus and the cortex. While research into this topic has focused mostly on neural activity in these structures, this study shows that astrocytes – a class of non-neural cells in the brain – also play a vital role.

The researchers show that interfering with astrocytes in the CA1 area of hippocampus disrupts the connection between the hippocampus and a region of frontal cortex. As a result, the recall of remote memories – those formed a long time ago – is less reliable, even while recall of recent memories remains normal. The study adds to a growing body of evidence that astrocytes play critical roles in memory processes.

Kol et al. (2020) Astrocytes contribute to remote memory formation by modulating hippocampal-cortical communication during learning. Nature Neuroscience DOI: https://doi.org/10.1038/s41593-020-0679-6

Memory structure linked to arousal levels

Although our life experiences are continuous, our memories of events are made of discrete, often sequential snapshots. How does this happen? In this study, researchers show that changes in context – for example being in a different spatial location, or a different auditory environment – are important. These contextual shifts produce changes in arousal (measured in this study by tracking pupil diameter), which may affect the way memories are structured for storage.

The authors point out that this could have implications for educational settings. If teachers can orchestrate rapid changes in the classroom environment, they can increase arousal and potentially help memory processing and retention.

Clewett et al. (2020) Pupil-linked arousal signals track the temporal organization of events in memory. Nature Communications 11: 4007 DOI: https://doi.org/10.1038/s41467-020-17851-9

Manipulating memory consolidation in humans

Memory consolidation involves the hippocampus replaying brain activity in a dialog with the cortex. This process occurs when we sleep, but also during restful waking periods. In humans, the evidence that such memory replay affects subsequent memory performance is mostly correlational – more replay is linked to better memory.

In this study, researchers give causal evidence that memory performance in humans depends on consolidation processes that occur while we are awake. By delivering transcranial magnetic stimulation (TMS) to a specific area of cortex, the researchers could disrupt memory retention. Under normal circumstances, this area of cortex is reactivated during consolidation, but when TMS was applied before consolidation can occur, less reactivation occurred. As a result, people who received TMS performed worse in a subsequent memory test.

Tambini and D’Esposito (2020) Causal contribution of awake post-encoding processes to episodic memory consolidation. Current Biology DOI: https://doi.org/10.1016/j.cub.2020.06.063