The processing of asymmetric and symmetric sentential conjunction

Bjorkman (2010) claims that symmetric 'and' involves coordination of CPs, while asymmetric ‘and’ involves TPs. If the processor is guided by structural considerations, we predict a possible two-way split in the processing costs of these structures. We examine the processing time involved in sentences interpreted as: (i) temporal, (ii) causal, (iii) logical, versus the distinctions of (i) asymmetric (TP structure), (ii) symmetric (CP structure). Symmetric 'and' structures involve longer processing times than those of asymmetric, causal 'and', and although the processing times of structures with logical 'and' are longer than with temporal 'and', this distinction does not approach statistical significance.