52. Listening to Podcasts for Maximal Retention | Interstitial time, task type, hour of day, driving vs undivided attention

• Listen to educational podcasts when your mind is fresh, such as when on your way to work rather than commuting home after a long day.
• Our limited amount of attention is relatively fixed, but it does depreciate as the day goes on and our energy wanes.
• Many choose to listen to podcasts during “interstitial time”, like when driving, exercising, or grocery shopping. You’re more likely to retain information if you’re doing a task that doesn’t require your full attention.

• Just like a computer will become bogged down and slow when it’s overloaded, so too does your brain processing speed diminish when cognitively overloaded.
• If your working memory is doing something fairly simple, like driving down the highway, then you have a fair amount of residual attention that you can spend on something like listening to a podcast. While driving through a busy city, however, the residual attention is going to be much less.

• Josh is often trying to cram podcasts into the interstitial spaces of life, but he finds that his mental ability to focus and vigilance are highest in the morning. This is the time that it makes the most sense to devote attention to something that involves integrating new information. As his ability to focus wanes, it becomes less and less productive to listen to informational podcasts.
• Similarly, it is common for people to do their “deep work” (that which requires the most attention) during the morning hours and “shallow work” later in the day.

• When we first wake up, the vigilance that we have is very helpful for detail oriented tasks where we have to focus and pay attention. Conversely, we’re not so great at coming up with creative and innovative solutions to problems at that time.
• As the day goes on and attention wanes, napping or taking a deliberate break can help restore vigilance.
• Towards the end of the day, we do better at solving creative problems and “thinking outside the box”.

• Lost among our culture is the value of a quiet moment while you’re sitting alone. “Go for a walk and leave your phone at home. Enjoy the silence. Enjoy the solitude.”

“A lot of the insights that we have come from quiet moments when we’re actually not focused.”

• On road trips or long drives with his wife, they will pause and discuss points that come up. There is a spaced repetition element to this, but it also enhances the listening experience.
• For educational podcasts (of which this is one) he reads the show notes and occasionally reads the linked references.
• When deciding which podcast to listen to, first looks at the podcatcher summary and time stamped topics to see if it’s interesting. The title doesn’t always reveal what’s inside.
• Educational podcasts only when fresh, such as on the way to work. If had time, would teach pearls from that show to the ED staff.
• Usually, it’s not so high brow, it’s listening while cleaning the garage or folding laundry.

• The authors presented 2 competing theories for this type of knowledge acquisition and tried to determine which applied to driving and listening.
• Limited capacity theory: “Humans have a limited capacity for the cognitive processing of information, because humans have finite resources available for learning. Each simultaneous task theoretically reduces available cognitive resources and may decrease their potential capacity for learning.”
• Theory of threaded cognition: “Tasks that do not require the same form of cognitive processing (e.g. walking and talking) may not compete for the same resources, thereby allowing for the performance of two distinct tasks without inhibiting the success of either component.”
• This was a randomized, crossover trial of 100 emergency medicine residents who listened to an educational podcast either while driving or when sitting undistracted in a room. After each podcast they took a test on the content.
• The findings: There was no significant difference between the driving and undistracted cohorts on the initial recall (74.2% vs. 73.3%) or delayed recall (52.2% vs. 52.0%).
• Bottom line: Getting your education or trying to learn while driving seems to be an effective strategy, at least as far as retention goes.

• Leave some of the interstitial cracks of time in your life open or free. Don’t fill all of them with things like podcasts. “Sitting in silence can have a rejuvenating, calming or stilling effect.”
• One of the most famous studies on the effect of silence was published in 2006. Study subjects were exposed to 5 different types of music of varying tempo and type, from slow sitar to fast Vivaldi.
• They found that passive listening to music accelerates respiratory rate, increases blood pressure and raises heart rate. The sympathetic activation of music was proportional to the tempo of the rhythm. The authors theorized that it was the level of concentration and attention that led to the arousal and sympathetic activation.
• The most striking part of the study was that a randomly inserted short pause of 2 minutes decreased blood pressure, minute ventilation, and heart rate. This relaxation effect was even greater than that seen at the end of 5 minutes of quiet relaxation at baseline.
• Bottom line: Inserting a few minutes of silence had a significant effect on relaxation, even more than listening to what is ostensibly relaxing music. Further, the effect of interspersed silence had an even greater relaxation impact than just baseline levels, giving importance to the contrast between listening and silence.

• In this study, the nerve growth was in the hippocampus which is associated with memory, learning, emotion, and memory. The results infer the benefit of silence.