A recent study of the use of metaphors in spoken language and various sign languages shows that certain types of metaphors are difficult to convey in sign language. The study, "Iconicity and metaphor: Constraints on metaphorical extension of iconic forms," to be published in the December 2010 issue of the scholarly journal Language, is authored by Irit Meir of the University of Haifa. A preprint version is available on line at: http://lsadc.org/info/documents/2010/press-releases/meir.pdf.
Dr. Meir's research sheds new light on the interrelations between two notions that play an important role in language and communication, iconicity and metaphor. This study shows that the iconicity of a form may constrain the possible metaphorical extensions that the form might take. Put another way, certain metaphorical expressions in spoken language cannot be "translated directly" into sign language if their form is iconic.
Sign languages are natural languages, with rich and complex grammatical structures and lexicons. Sign languages have rich use of metaphors. But quite often, when trying to translate metaphors from a spoken language to a sign language, we find that it is impossible to use the same words. For example, it is impossible to use the sign FLY (in Israeli Sign Language and American Sign Language) in the expression "time flies" or "the day just flew by". The metaphorical uses of a word such as FLY are impossible because of the form of this sign, in particular, its iconicity. The sign for FLY is produced by moving the arms as if flapping one's wings. But in the expression "time flies", we do not mean that time is flapping its wings. Rather, the metaphor is built on an implication of the action of flying, namely that it is a very fast way of motion. So there is a clash between what the form of the sign encodes (wing flapping) and the aspect of meaning on which the metaphor is built (fast movement).
When such a clash occurs, the metaphorical use is not possible. The meaning components reflected by the form of the (iconic) verb and the meaning component which serves as the basis for its metaphorical use should be congruent. If they are not, then the sign cannot be used for the specific metaphorical use in question. Iconic signs, then, are more restricted in the metaphorical extensions they can undergo than non-iconic signs, because their form is not arbitrary. The effects of iconicity on metaphors are much more salient in signed languages, because of their better ability to express many concepts in an iconic way. Sign languages, then, are instrumental in getting better understanding of metaphors and the forces that shape them.
EurekAlert. 2010. "Sign languages help us understand the nature of metaphors". EurekAlert. Posted: December 10, 2010. Available online: http://www.eurekalert.org/pub_releases/2010-12/lsoa-slh121010.php