No abstract

Three experiments investigated the nature of the information required for the lexical access of visual words. A four-field masking procedure was used, in which the presentation of consecutive prime and target letter strings was preceded and followed by presentations of a pattern mask. This procedure prevented subjects from identifying, and thus intentionally using, prime information. Experiment I extablished the existence of a semantic priming effect on target identification, demonstrating the lexical access of primes under these conditions. It also showed a word repetition effect independent of letter case. Experiment I1 tested whether this repetition effect was due to the activation of graphemic or phonemic information. The graphemic and phonemic similarity of primes and targets was varied. No evidence for phonemic priming was found, although a graphemic priming effect, independent of the physical similarity of the stimuli, was obtained. Finally Experiment I11 demonstrated that, irrespective of whether the prime was a word or a nonword, graphemic priming was equally effective. In both Experiments I1 and 111, however, the word repetition effect was stronger than the graphemic priming effect. It is argued that facilitation from graphemic priming was due to the prime activating a target representation coded for abstract (non-visual) graphemic features, such as letter identities. The extra facilitation from same identity priming was attributed to semantic as well as graphemic activation. The implications of these results for models of word recognition are discussed.

reported by Hillinger (1980, Experiment 3). He used a priming technique in which subjects made a lexical decision about visual prime-and target-letter strings. In a test that assessed whether phonological information is automatically accessed, performance when targets were primed by phonologically similar but graphemically different words (e.g., EIGHT-MATE) was compared with performance when primes were neutral (e.g., ******-MATE). Hillinger found that, relative to the neutral-prime baseline, lexical decisions were facilitated by phonological priming. This indicates that phonological information from the prime affected target recognition. There are at least two ways in which such a facilitatory priming effect could occur. One is by the prime automatically activating representations common to both stimuli. The other is by subjects using phonological information from the prime to anticipate the target (Posner, 1978; Posner & Snyder, 1975). Such an anticipatory strategy would lead to incorrect expectations when primes and targets are unrelated, precipitating an inhibition effect relative to the neutral condition (Mclean & Shulman, 1978; Neely, 1977). Since, in Hillinger's (1980) study, no inhibition effect was found when primes and targets were phonologically unrelated (e.g., VEIL-MATE), it appears that subjects did not anticipate targets from the phonological properties of primes.

One of the most popular and influential theories of word processing, dual-route theory, proposes that there are two functionally independent means of processing words, one involving access to lexical knowledge and the other involving nonlexical grapheme-to-phoneme conversion. Three topics germane to this theory are the processing of nonwords, spelling regularity effects, and the manner in which reading may be impaired following selective damage to either route. This paper evaluates evidence on these topics, and in each case the claims of the theory for an independent nonlexical processing route are called into question. This conclusion is further supported by a discussion of the linguistic constraints that limit any nonlexical grapheme—phoneme conversion process. Some alternative approaches to visual word processing, which share the assumption that lexical knowledge can guide the assembly of phonological information, are discussed. It is argued that these approaches should direct future research.

The research reported here is part of a larger project which seeks to combine serious games (or games based learning) with location based services to help people with intellectual disability and additional sensory impairments to develop work based skills. Specifically this paper reports on where these approaches are combined to scaffold the learning of new routes and ultimately independent travel to new work and educational opportunities. A phased development methodology is applied in a user sensitive manner, to ensure that user feedback drives the ongoing development process. Methods to structure this include group feedback on conceptual storyboards, expert review of prototypes using usability heuristics relating to the main system goals, and finally co-discovery methods with student pairs exploring all three modes of the system in real world contexts. Aspects of developmental and cognitive psychological theories are also reviewed and it is suggested that combining games based learning approaches with location based services is an appropriate combination of technologies for an application specifically designed to scaffold route learning for this target audience.