Mental Model
Sleep Architecture (Walker): NREM and REM Cycles
Sleep architecture is the distribution and sequence of non-REM stages N1, N2, and N3 and REM sleep
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Mental Model
Sleep Architecture Model (Comprehensive)
Sleep architecture describes the structured cycling of sleep stages throughout the night: NREM Stage 1 (light transition), NREM Stage 2 (spindle-rich consolidation), NREM Stage 3 (deep/slow-wave sleep for physical restor…
Mental Model
Sleep Hygiene Checklist Protocol
A comprehensive protocol for optimizing sleep quality through environmental, behavioral, and timing interventions, based on sleep medicine research
Mental Model
Sleeper Effect
The counterintuitive finding that persuasive messages from low-credibility sources become MORE persuasive over time, not less
Cognitive Move
slide
One screen, seen for well under a minute while someone else talks over it. The reader does not control the pace and cannot go back. Anything that takes more than a few seconds to decode is simply not read, so a slide holds one point, one figure, and the fewest words that make the point land without narration.
Cognitive Move
slider or parameter
One continuous input the reader drags, with the rest of the picture recomputing as it moves. The finding is not any single position but the shape of the response: where the curve is flat, where it bends, and where it crosses a line that matters. Mark the default, and label the units and the range so the reader knows what they are moving.
Mental Model
Slippery Slope
A slippery-slope argument claims that an initial step increases the risk of a later progression or outcome
Mental Model
Slippery Slope Argument
An argument that an initial step can enable or increase the likelihood of a sequence leading to an unacceptable result.
Mental Model
Slippery Slope in Ethical Reasoning
The ethical slippery slope describes how small, seemingly innocuous moral compromises establish precedents and psychological patterns that lead to progressively larger violations
Cognitive Move
Small multiples
Build one small template and repeat it identically for every case, so differences pop out instead of hiding. Because the shape stays fixed, your eye only has to notice what changed, rather than re-learning a fresh layout for each item.
Mental Model
Small World Networks (Six Degrees)
The empirical finding that most nodes in large social networks can reach any other node through a surprisingly small number of intermediate connections—typically around six (Milgram's 'six degrees of separation')
Mental Model
SMART Formula
A flexible objective-writing checklist; common modern wording is Specific, Measurable, Achievable, Relevant, and Time-bound, while Doran's original used Assignable and Realistic.
Mental Model
Smart Home Automation Logic
Smart home automation follows trigger-condition-action logic: IF trigger occurs (motion detected, time reached) AND conditions met (nighttime, someone home) THEN execute action (lights on, thermostat adjust)
Cognitive Move
Snapshot to Movie
When a present state seems inexplicable, draw the before, transition, and now frames, then predict the next one.
Cognitive Move
Snowball / Flywheel
A hypothesis that accumulated success or decline is making each next turn easier in the same direction.
Cognitive Move
Snowball or Thermostat?
Test whether a deviation amplifies itself or recruits its own correction.
Mental Model
Sobremesa (Table Talk Culture)
Sobremesa (literally 'over the table') is the Spanish and Latin American practice of lingering at the table after a meal for extended conversation, digestion, and social bonding -- sometimes for hours
Mental Model
Social Capital (Bonding vs Bridging)
Putnam's distinction between two forms of social capital: bonding capital (strong ties within homogeneous groups that provide support, trust, and solidarity) and bridging capital (weak ties across different groups that p…
Mental Model
Social Contagion of Habits
Christakis and Fowler's Framingham Heart Study network data revealed behaviors spread through social networks: if a friend becomes obese, your risk increases 57%
Mental Model
Social Convoy Model (Kahn & Antonucci)
A life-course model of significant social relationships whose composition, closeness, support, and quality change with personal and situational factors
Mental Model
Social Convoy Model Applied to Adult Life
Robert Kahn and Toni Antonucci's Social Convoy Model visualizes each person surrounded by concentric circles of relationships that travel with them through life — like a convoy of ships traveling together
Mental Model
Social Determinants of Health
The social determinants of health (SDOH) framework recognizes that clinical healthcare accounts for only 10-20% of health outcomes, while social and environmental factors—income, education, housing, food access, employme…
Cognitive Move
social graph
A node-link diagram whose nodes are people and whose edges are one named relationship, such as has worked with, has introduced, or owes a favor to. Naming the edge is the whole discipline. It is what stops the picture from collapsing into a general sense of who knows whom, and it is what makes a broker, someone standing between two groups that do not otherwise touch, findable.
Mental Model
Social Identity Theory (Tajfel) — Applied
Henri Tajfel's Social Identity Theory (SIT) proposes that a significant portion of self-concept derives from membership in social groups—professional, ethnic, national, organizational, ideological, generational