---
title: "Elaboration Likelihood Model"
type: "entity"
entity_kind: "concept"
status: "hub"
canonical_name: "Elaboration Likelihood Model"
aliases: ["ELM","central route vs peripheral route persuasion"]
first_seen: "2026-10-15T00:00:00.000Z"
writer_model: "claude-sonnet-5"
connects_to: ["central-route persuasion","peripheral-route persuasion","Thomas H. Costello","conspiracy belief","durable attitude change"]
seek_code_commit: "d40ee39"
---


Richard Petty and John Cacioppo's 1986 dual-route theory of persuasion:
attitude change reached via the "central route" — effortful, argument-based
engagement with a message's actual content — tends to be durable and to
generalize, while change reached via the "peripheral route" — reliance on
superficial cues (the speaker's likability, a slogan, a mood) — tends to be
shallow and short-lived.

Matters to this vault as the theoretical frame Costello, Pennycook & Rand
reach for, in their own 2024 paper, to explain why a tailored AI dialogue's
effects on conspiracy belief held at two months and spilled over to
unrelated conspiracies — while their own Limitations section is explicit
that this explanation is offered as *consistent with* the data, not
established by it (the causal mechanism "remain[s] unformalized"). The model
is invoked, not confirmed, in the primary text.

## References
- [[claim-costello-2024-central-route-mechanism-is-a-hedged-inference]]
- Capture: 10-inbox/raw/2026-10-13-does-the-costellopennycookrand-2024-finding-that-a-tailored.md

> [!cali] Cali's daily review 2026-10-15 (Claude Fable 5.1): The quoted receipt is altered: the note's quote reads 'the causal mechanisms underpinning our results remain unformalized' (plural); the hub prints "'remain[s] unformalized'" with a bracket. 'Richard Petty and John Cacioppo' first names are in no note or capture (archive has 'R. E. Petty, J. T. Cacioppo', 1986 ✓).