Right hemisphere contributions to the comprehension of low-imagery words

A priming experiment, with normal university students as subjects, was used to investigate whether the right cerebral hemisphere contributes to the co mprehension of low-imagery words. Each hemisphere's access to semantic repr esentations of low-imagery words was gauged by comparing responses to low-i magery targets preceded by associated low-imagery primes (e.g., BELIEF-IDEA L) with responses to the same targets when they were preceded by unrelated primes (e.g., FATE-IDEAL). All primes and targets were independently projec ted to the left or right visual fields (LVF or RVF), and temporally separat ed by a stimulus onset asynchrony of 250 ms. There was a clear RVF advantag e in response speed and accuracy measures, confirming the left hemisphere's advantage in processing low-imagery words. Nonetheless, the priming effect s provided evidence that the right hemisphere contributes to the comprehens ion of low-imagery words, as primes projected to the RVF equally facilitate d responses to associated targets subsequently appearing in either visual f ield. In contrast, primes directed to the LVF did not facilitate responses to associated targets projected to the LVF or RVF. The results suggest that low-imagery words projected to the left hemisphere activated low-imagery a ssociates in both hemispheres to an equivalent degree, whereas low-imagery primes directed to the right hemisphere failed to activate low-imagery asso ciates in either hemisphere. Like Kounios and Holcomb's (1994) study of eve nt-related response potentials evoked by abstract and concrete words, the f indings indicate that while the left hemisphere is the primary processor of low-imagery/ abstract words, the right hemisphere plays a subsidiary role in the comprehension of these words.