Theory Card 008 — Cognitive Load / Structure
Research lens
Cognitive load theory argues that solving unfamiliar problems can consume the same limited mental resources needed to learn and reason clearly. In the Structure stage of BASIC, the goal is to externalize a plan, invariant, or architecture. That makes this concept especially relevant here, because it shapes how much mental work the candidate is trying to carry at once and what gets made explicit.
Why it matters in SWE interviews
In interviews, this shows up when a candidate knows the topic but melts down as soon as the prompt becomes multi-step or ambiguous. BASIC helps by giving the brain a fixed order of operations instead of asking it to invent the process from scratch every time. In practice, Structure is where the candidate should ask: What is the sequence, helper structure, invariant, or component map that will carry the solution? That question acts like a cognitive boundary. It protects the answer from turning into an unstructured search.
BASIC move
A strong move here is to make the plan visible before full execution. For Cognitive Load, that means deliberately naming the important units instead of juggling them implicitly. The interviewer sees cleaner reasoning, and the candidate benefits from reduces hidden-state thinking and makes reasoning inspectable.
Common miss
The common miss is trying to optimize and code at the same time, which overloads memory and causes avoidable confusion. When that happens, the candidate usually feels busy, but the answer is actually becoming less inspectable.
Practice prompt
“While practicing, pause at the Structure step and explain how Cognitive Load changes the way you would handle the prompt.”