Introduction

In ch. 1 (section 1.4.4.2) we outlined the model of the mind we had previously argued for in an attempt to accommodate the abilities both of Christopher and the general population. In this chapter we return to the role of modality, sign versus speech, in the representation of language in the human mind. We begin by summarising the putative modality differences between signed and spoken languages, looking at ‘articulatory’ differences, at deixis and the use of space more generally, at iconicity and the special case of classifiers, and at the role of facial action (the other major area where signed and spoken languages look superficially most different). We then elaborate a revised model of the mind. It should be emphasised that we cannot hope to address the whole range of phenomena that have been treated under the heading ‘modality’ in sign language research and will restrict ourselves to dealing with issues pertinent to the construction of a model adequate to describe the abilities of Christopher and those we have compared him with. We end with a detailed exemplification of how the model allows for the description of the full range of Christopher's (and others’) abilities, and finally draw our conclusions.

Modality effects

In this section we revisit and elaborate our earlier discussion of the differences between signed and spoken languages and include some discussion of the results of Christopher's learning of BSL.