The DRC Model of reading

The DRC Model

The DRC model is a computational model of reading which is intended to explain how skilled readers perform certain basic reading tasks. The acronym emphasizes the two fundamental properties of the model: it is a Dual Route model, and within the model information processing occurs in a Cascaded fashion.

The model consists of three routes, the lexical semantic route, the lexical nonsemantic route, and the GPC route. Each route is composed of a number of interacting layers. These layers contain sets of units. The units represent the smallest individual symbolic parts of the model, such as words in the orthographic lexicon or letters in the letter unit layer.

There are two ways in which the units of different layers interact. One is through inhibition, where the activation of a unit makes it more difficult for the activation of other units to rise. The other is through excitation, where the activation of a unit contributes to the activation of other units. Units may also interact on the same level through lateral inhibition.

The 2001 Psychological Review paper on DRC (9.1MB PDF) describes version 1.0 of the model in detail.

Simulator

A simulator of the lexical nonsemantic and GPC routes is available for Mac OS X, Linux (x86) and Windows. It is a command line application, so it must be operated from the Terminal application in Mac OS X, the Shell in Linux or the Command (or DOS) Prompt in Windows.

Differences between DRC 1.2 and DRC 1.0 (PDF)
DRC 1.2 Incremental Modelling (PDF)
DRC Mac
DRC Linux (x86_64)
DRC Linux (armv7l, Raspberry Pi)
DRC Windows

DRC-SEM

An experimental version of DRC that includes a semantics layer.

DRC-SEM Mac
DRC-SEM Linux (x86_64)
DRC-SEM Linux (armv7l, Raspberry Pi)
DRC-SEM Windows

DRCView

A Max OS X app for viewing DRC activation-level files.

DRCView

Related Papers

1. Coltheart, M., Curtis, B. Atkins, P. and Haller, M. (1993). Models of reading aloud: Dual-route and parallel-distributed-processing approaches. Psychological Review, 100, 589-608.

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2. Coltheart, M. and Rastle, K. (1994). Serial Processing in Reading Aloud: Evidence for Dual-Route Models of Reading. Journal of Experimental Psychology: Human Perception and Performance, 20, 1197-1211.

3. Coltheart, M. and Leahy, J. (1996). Assessment of lexical and nonlexical reading abilities in children: Some normative data. Australian Journal of Psychology, 48, 136-140.

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