St Lukes Grammar School


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  • Teenagers and Sleep

    Posted On 12 June, 2020

    Teenagers and Sleep

    Alma Loreaux | Dean of Learning | Grammar News 12 June 2020


    Over the past two weeks, we have been reviewing the reflections by students on their experience of Off-Campus Learning. We have asked them about aspects of their learning which they would like to keep and we have also asked them to reflect on and identify what they will miss now that they are back in the regular school routine. 


    Not surprisingly, many of our students are identifying their need to sleep in as a major factor they will miss. So, I did a little bit of research on teenagers and their sleep patterns. What was particularly helpful was Dr Jared Cooney’s review of the paper A Mechanism for Learning with Sleep Spindles(Adrien Peyrache and Julie Seibt, April 2020). Dr Cooney distills key ideas of the paper which I have paraphrased here. 


    Before we move to the details about how much sleep teenagers need, let’s think about the neuroplasticity of our brain. Brain plasticity is the ability of the brain to change structurally or physiologically. This change means that our synaptic connections are always increasing or decreasing. When we are awake, our brain is constantly building new connections. During sleep, the brain consolidates the day and ‘resets’. Yet, the brain manages to hold onto and lock away key memories. What scientists believe happens while we sleep is that our hippocampus cycles through our memories from the day we have just had. In a sense, it replays the memories and pushes them out to the edge of our brain where, what scientists refer to as sleep spindles, activate and hold onto certain memories. Therefore, if we don’t sleep, we don’t make the memories that we need to make the learning stick. 


    While we sleep, we go into stages of deep sleep, which form our sleep cycle. Each cycle is approximately 90 minutes in duration and we go through 3-5 cycles each night. Our memories are getting locked down by the sleep spindles during the second sleep cycle, after our brain has had a chance to ‘replay’ initial memories from the day. 


    For teenagers, the experience of sleep is rather different due to their changed circadian rhythm. The circadian rhythm changes in teenage years, shifting two-three hours later than for young children and adults. As such, teenagers go to bed later. Yet, they are still required to wake up early in time for the school day. This means that their sleep cycle does not allow for a full ‘replay’ and consolidation of memory. As they don’t get all of their sleep cycles, their memory consolidation lasts only 1.5hrs. Consequently, teenagers’ memory retention decreases. 


    So, what can we do to help teenagers consolidate their memories in a way that will help their learning?


    1. Establish a set routine. It is advisable for teenagers to start unwinding at the same time each day. This involves, putting devices down, switching off notifications, not watching TV right before bedtime, and identifying a set series of small steps that signal to the body that it is time to sleep. This won’t happen instantly, so teenagers must persevere with their routine no matter what assignment needs completing, or no matter what message is popping up on their devices. 

    2. Activate reflectiveness through planning, revising, distilling and meta-learning. To assist in memory retention, sleep is not the only factor. Students need to learn to develop effective learning strategies that allow them to retrieve information and space out their study over time. This will enable them to move away from late-night cramming and move them towards effectively planning their learning, revising concepts at regular and purposeful intervals, distill key ideas and become cognisant of their own learning process.