How can I take effective notes during lectures on complex topics like quantum mechanics and organic chemistry without getting overwhelmed by the amount of new information?

Focus on capturing just the core concepts and the relationships between them instead of trying to write down every formula or detail. As you listen, pause after each major idea, write a one‑sentence “concept headline” that names the principle (e.g., “wave‑function collapse describes measurement outcome”) and then add a quick arrow or bracket linking it to the preceding headline, noting any cause‑effect or prerequisite (e.g., “→ requires superposition”). This skeletal outline forces you to process the material in real time, so you’re actively deciding what’s essential, and the visual links make it easier to reconstruct the full picture later. For instance, in a quantum‑mechanics lecture you might end up with a chain of three headlines—“quantum states live in Hilbert space → observables are operators → measurement projects onto eigenstates”—instead of a wall of equations. Because you’ve already organized the ideas, reviewing the outline triggers the deeper details without feeling overwhelming, and you’ll notice retention improving as you spend less time copying and more time connecting. This streamlined approach keeps notes manageable while preserving the conceptual scaffolding you need for complex subjects.