Tool Cognitive Load
Category: Cognitive Transport · Since: v18.27.0 · Tier: All
Estimate the cognitive load a specific persona experiences on a page, broken down across 8 dimensions. Identifies the bottleneck dimension — whether the persona is overwhelmed by information density, visual complexity, too many choices, or something else.
Why This Matters
A page that's fine for a power-user might overwhelm an ADHD user. This tool quantifies exactly why — not just "it's too complex" but "the 53 choice points create decision fatigue at 0.37 load, and the animations create attention fragmentation at 0.50 load."
Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
persona |
string | Yes | Persona name |
informationDensity |
number (0-1) | Yes | Content density (0=sparse, 1=dense) |
visualComplexity |
number (0-1) | Yes | Visual complexity (0=simple, 1=complex) |
interactiveElements |
number | Yes | Number of interactive elements |
textDensity |
number (0-1) | Yes | Text heaviness (0=minimal, 1=wall of text) |
animationLevel |
number (0-1) | Yes | Animation/motion amount |
choiceCount |
number | Yes | Number of decision points/options |
navigationDepth |
number | Yes | Clicks needed to reach content |
Example
Estimate cognitive load for an ADHD user on a page with high animation and 30 interactive elements
Response
{
"persona": "cognitive-adhd",
"totalLoad": 0.41,
"overloaded": false,
"bottleneck": "attention",
"breakdown": {
"information": 0.50,
"visual": 0.50,
"attention": 0.50,
"decision": 0.37,
"motor": 0.50,
"text": 0.50,
"memory": 0.15,
"patience": 0.22
},
"recommendation": "cognitive-adhd can handle this page. Closest to overload on: attention."
}
The 8 Dimensions
| Dimension | What It Measures | High For |
|---|---|---|
| Information | Content density vs comprehension | Low comprehension personas |
| Visual | Visual complexity vs processing | Low visual processing personas |
| Attention | Animations vs attention capacity | ADHD, easily distracted |
| Decision | Choice count (Hick-Hyman) vs decision style | Indecisive, satisficing |
| Motor | Interactive elements vs motor precision | Motor impairment, elderly |
| Text | Text density vs text processing | Dyslexia, low literacy |
| Memory | Navigation depth vs working memory | Low working memory |
| Patience | Baseline impatience factor | Impatient personas |
Automatic Integration
When empathy_audit runs, cognitive load is automatically computed for each persona using page metrics extracted via extractPageMetrics(). You don't need to call this tool separately during empathy audits — it's included in the response as cognitiveLoad.
Related Tools
cognitive_distance— Distance between personascognitive_coverage— Select maximally different personascognitive_interpolate— Blend between personasempathy_audit— Full accessibility audit (includes cognitive load)attention_analysis— Where attention goes on a page