Building an Investment Knowledge Network: Cognitive Science Tactics for Long-Term Podcast Learning

A step-by-step guide to curating, capturing, and connecting ideas from podcasts: A workflow for investors

Canva. (n.d.). [Meme with text "There's just TOO many podcasts!"] [Digital image]. Retrieved March 15, 2025, from https://www.canva.com/

This may not be your typical post featuring investment ideas, but I believe the topics discussed here could, even if indirectly, enhance your investment process. Let’s dive in.

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Podcast content creation exploded after the pandemic and never stopped. As of January 2025, there are 4,396,378 total podcasts registered around the world¹. More so, current data shows there are now over 103,286,051 episodes published in Apple Podcasts.

If you are a podcast fan like me, you know that it’s impossible to keep up with all the interesting new releases that come up each week.

Not only that, but too many times I have listened to an episode while running or working out, thinking the host was sharing an exciting idea, and then forgot about it.

As an investor, you probably rely on podcasts for valuable information – in fact, 48% of investors use financial podcasts as a source of information, and 38% have acted on that information in investment decisions². Yet human memory is fallible.

Podcasts are a good source of knowledge locked in audio, but it’s really challenging to capture insights and take notes on those memorable moments.

Why? We usually listen to podcast while doing other things.

So, we listen, nod along, and then oops – the details are gone, they fade away.

But, why does this happen? Cognitive research shows that our brains quickly discard information we don’t actively engage with. Studies suggest people forget about 50% of new information within an hour, and up to 70% within 24 hours if there’s no reinforcement³.

In other words, simply hearing something once isn’t enough to make it stick. Memory isn’t a passive recording device; rather, “your memory is a product of what you think about” – we remember what we actively process, not just what we hear in passing⁴.

Without a system to capture and revisit ideas, even game-changing insights you learn listening to podcasts can slip away.

The good news is that you can beat the forgetting curve.

In this article I share an easy, step-by-step workflow to curate, capture, and connect ideas from podcasts so that valuable insights become part of your knowledge network to improve your investment process.

Let’s get right into it.

Polymath Investor. (2025). “Network of Knowledge”.

Step 1: Preview, Have a Purpose and Listen Actively

With thousands of podcasts available, the first step is curation – deciding what to listen to and how to listen. As a professional investor or analyst, your time is limited.

Rather than passively tuning in to whatever’s on, we have to be intentional in selecting episodes that align with your research purpose or knowledge gaps. Scan episode descriptions or show notes to get a graps of what the podcast is about.

There are dozens of podcasts apps that help you do this.

The one I use is called Snipd. With this app, you can create AI-generated summaries of podcast episodes. This give you a quick overview of the topics, guests, and key takeaways before you even hit play.

Think of it as getting an executive summary upfront – you can quickly assess if an episode is worth your time. Not only that, If you conclude the podcast is relevant, then having done this preview step will jump start your comprehension on the topic.

The second part of this step is to define your purpose. Have a goal to listen to the podcast. What are you expecting to get after you finish listening.

Define the purpose and keep it in mind.

Third part of step one, bear with me, is to listen actively.

Active listening means engaging with the content – jotting mental notes, anticipating what might be important, and staying focused. It’s easy to treat podcasts as background noise, but for retention, a bit of mental effort goes a long way. As cognitive science tells us, whatever we think about is what we remember⁵.

So there you have it, the three parts of Step 1 are:

1. Preview the meta information of the episode.

2. Mentally define a goal or a purpose for listening to the podcast.

3. Engage in active listening.

Before diving into this process, keep in mind that it’s designed for when you want to boost retention and comprehension—typically for work or research purposes. If you’re listening to a podcast purely for enjoyment, there’s no need to bother with the full technique.

Step 2: Capture Key Insights with Snipd

Once you’re listening to a curated, high-value podcast, the goal is to capture the key insights in the moment. It’s not enough to assume you’ll remember them later (you likely won’t, as we learned).

This is where Snipd comes in. This app lets you save highlights from podcasts instantly, almost like highlighting text in a book, but for audio (I have no affiliation with the app, it’s just useful).

Using Snipd, whenever you hear something noteworthy – a statistic, a quote, an investment idea – you can tap a button (or even use your earpods controls) to create a "snip" of that segment.

All you have to do is triple-tap your headphones or hit the Snipd button, and the app will automatically save that moment, select the best start and end points to capture the full context, and generate a transcript and key takeaways of the snippet.

In essence, Snipd acts as your digital highlighter and note-taker for audio. You don’t have to stop the conversation or scramble for a pen; keep listening and let the app grab the insight for you.

Each snippet you save is stored in Snipd’s library with the audio clip, transcript, and even an AI-generated summary of that clip. For example, if an expert gives a 2-minute explanation of emerging AI trends in fintech, you can snip it – later, you’ll have the verbatim transcript and a concise summary of it.

After finishing the episode, take a moment to review your Snipd highlights. This step in itself is a form of active recall – you’re replaying the important points in your mind shortly after hearing them, which helps reinforce memory.

Now, you have to move these insights into a system where they can connect with your broader knowledge base.

Step 3: Connect and Organize Notes in Obsidian

Capturing snippets is good, but it’s only the start. The next step is to connect those insights to the rest of your knowledge so they truly become useful. For this, I use Obsidian, a great note-taking and knowledge management app. You can use whatever you want here-Notion, Roam, Logseq…there are plenty.

Obsidian and the likes are often described as a “second brain” – it allows you to create a network of interlinked notes, helping you see relationships between ideas. This is great for investors and analysts synthesizing information across many sources, if you search on Youtube you will find many ways in how people are using Obsidian.

But let’s continue with the process on how to move on from Snipd.

First, get your Snipd highlights into Obsidian. Fortunately, Snipd makes this easy: you can export your saved podcast insights as Markdown and sync them with Obsidian.

The goal here is to make each snippet (with its transcript and notes) a note in your Obsidian vault.

Now you can enrich and organize these notes. Give each snippet note some context – for example, tag it with topics or link it to relevant existing notes. If you have an Obsidian note on a particular company or trend, link your new podcast insight to that note.

For instance, if you snipped a quote about electric vehicle adoption rates and you maintain a note on “EV Market Trends,” link them. Obsidian’s strength lies in these bidirectional links: over time, you’ll create a web of connected ideas (this practice is related to the Zettelkasten method of taking notes, but that’s for another post).

So, why go through this linking step? Because connected notes allow you to see relationships and connections that would otherwise be invisible⁶.

For an investor, these connections can spark insights that lead to sharper questions or stronger investment hypotheses. Think of it as building a knowledge network: each podcast insight becomes a node, linking to other pieces of knowledge you’ve gathered—from articles, books, research, and more—forming a richer, more detailed picture. Insights often emerge from spotting connections others miss, and an Obsidian note system makes those links concrete. In fact, many ideas for this newsletter come directly from that network.

"Obsidian has a feature that visually displays the connections in your knowledge network. I exported a video showing how mine has evolved:

Organizing notes also means clarifying them. Take a minute to write a brief summary or commentary in your own words on the snippet. This extra effort of rephrasing and elaborating further cements the knowledge (another principle from cognitive science: the more you do with information, the more it sticks).

Now that your idea is captured and connected, one step remains: ensuring you truly remember it long-term.

Step 4: Reinforce and Retain Insights with Anki

The final piece of the workflow addresses long-term retention. You’ve captured an insight and integrated it into your knowledge network; now, how do you make sure you can recall it next week, next month, or next year? This is where Anki, a spaced repetition flashcard tool, comes in.

Anki is an app that uses two proven techniques from cognitive science: active recall testing and spaced repetition⁷. I’ve written before about different methods and techniques related to this here:

The idea is simple but powerful. You create flashcards from your notes – for example, one side could ask, “What did expert X say about emerging market consumer trends on X podcast?” and the other side contains the answer or key point. Anki will quiz you on these cards over time, scheduling them at intervals that get spaced out (every few days, then weeks, then months) as you remember them correctly. If you struggle to recall a card, Anki shows it more frequently until it sticks.

Why go to this length? Because active recall (trying to retrieve information from memory) is far more effective at building strong memories than passive review, by a mile.

The act of recalling an insight strengthens the neural pathways related to that memory, making it easier to retrieve in the future. And by spacing out reviews over time (spaced repetition), you’re countering the forgetting curve I discussed earlier – effectively telling your brain “this piece of information matters, don’t drop it.” Research-backed evidence supports this approach: repetition with active recall significantly boosts learning retention and slows down forgetting⁸.

In practice, you don’t need to make a flashcard for every snippet or snipd – focus on high-impact facts or concepts you really want to internalize.

Many professionals use Anki to remember formulas, checklists, or key quotes. As an investor, you might create cards for things like macroeconomic signals, historical market analogies, or nuggets of wisdom from legendary investors mentioned in podcasts.

Over time, reviewing these cards for a few minutes each day will ensure these insights are at your fingertips when you need them – whether in a client meeting, an investment committee discussion, or writing a report.

There are even community plugins to streamline this step, such as Obsidian-to-Anki exporters, which can convert your marked-up notes into Anki cards automatically. But even doing it manually is a worthwhile habit: the process of crafting a question and answer itself makes you engage deeply with the material.

Remember, the more you make your brain work with the information, the more it will reward you by remembering it. Spaced repetition is like compound interest for knowledge – small efforts added over time result in a good memory that sets you apart as someone who truly remembers what they learn.

Anki provides a good tracking calendar for the days you worked with the app, I’m still aiming for the perfect year.

Auditory Contrast Adaptation Or Tempo Tunning

Podcasts often include drawn-out introductions and sponsor segments, like Tim Ferriss’s show, where he delivers an extended intro and reads through all his sponsor ads upfront.

Now, obviously I’d skip these parts and while skipping them entirely is an option, you can also train your brain to process them more efficiently using a clever speed trick that taps into how your brain adapts to auditory input.

Start by cranking the playback speed to 2x or 2.5x during these less engaging sections. At this pace, the words blur into a rapid stream, and your brain, which is wired to seek patterns and meaning, shifts into a heightened state of alertness to keep up. It won’t fully decode every word—and that’s fine—because the goal is to prime your neural circuits for faster processing, not to absorb the ads.

When the main content starts, dial the speed back to may be 1.6x. Here’s where the brain’s adaptability kicks in: after wrestling with the near-incomprehensible 2x, 1.6x feels slower and more manageable by comparison, almost like regular speed. Yet, because your auditory processing has been revved up, you’ll still comprehend the material faster than you would at 1x. This works because your brain recalibrates its perception of "normal" based on the contrast, a bit like how your eyes adjust to light after being in the dark.

Play around with this technique—push the intro to even higher speeds like 3x if you’re feeling bold, then settle into a sweet spot (say, 1.6x to 1.8x) for the meat of the episode.

You’re essentially hacking your brain’s ability to adapt to tempo, training it to listen and process more efficiently over time. With practice, you’ll find the fastest pace you can handle while still grasping the ideas.

Conclusion: From Passive Listening to Building Your Own Knowledge Network For Better Investments

By using this capture-connect-reinforce system, you transform podcast listening from a passive experience into an active learning process. Instead of vaguely recalling that “I heard something about supply chains on a podcast once,” you’ll have the specifics at hand, linked to other knowledge and committed to memory.

The true power of this approach lies in the knowledge network you build. Each snippet captured, each note connected, and each flashcard reviewed is an investment in your personal intellectual capital.

Over weeks and months, your Obsidian vault will grow into a rich map of ideas – a unique database of industry wisdom, market anecdotes, and strategic frameworks all cross-referenced. This network not only helps you remember facts, but also encourages seeing the bigger picture: you might draw connections between a geopolitical insight from a podcast and data from a recent earnings call. Your second brain becomes an “insight engine” that keeps on giving.

So next time you press play on that podcast, be ready to snip, link, and review. Your future self (and perhaps your portfolio) will thank you for it!

1. According to podcastindex.org

2. Brunswick Group. (2019, February 13). Investors turn up the volume on podcasts. Retrieved from https://www.brunswickgroup.com/digital-investor-survey-investors-turn-up-the-volume-on-podcasts-i9573/

3. Gupta, D. (2022, January 7). Ebbinghaus's forgetting curve: How to overcome it. Whatfix. Retrieved from https://whatfix.com/blog/ebbinghaus-forgetting-curve/

4. Willingham, D. T. (2021, Summer). Ask the cognitive scientist: Why do students remember everything that's on television and forget everything I say? American Educator. Retrieved from https://www.aft.org/ae/summer2021/willingham

5. Willingham, D. T. (2021, Summer). Ask the cognitive scientist: Why do students remember everything that's on television and forget everything I say? American Educator. Retrieved from https://www.aft.org/ae/summer2021/willingham

6. Novis, S. (n.d.). How I set up my personal knowledge management system. Obsidian Publish. Retrieved from https://publish.obsidian.md/scottnovis/Published/How+I+Setup+my+Personal+Knowledge+Management+System

7. Anki Manual. (n.d.). Background. Retrieved from https://docs.ankiweb.net/background.html

8. Gupta, D. (2022, January 7). Ebbinghaus's forgetting curve: How to overcome it. Whatfix. Retrieved from https://whatfix.com/blog/ebbinghaus-forgetting-curve/