The Cognitive Processes And Neural Mechanisms Of Different Metaphors At The Lexical Level

One of the most interesting phenomena of human language is the widespread use of metaphor,in which the intended meaning does not coincide with the literal meaning.For example,when we say that “Time is money”,we do not mean to say that “money” is really “time”.Instead,our intention is to suggest that some properties of money(eg: the value of money)can be attributed to time.In recent decades,experimental work on the processing of metaphor has been expanding rapidly.There has two hot issues which previous studies most concerned about,one is the processing differences between metaphor and literal,the other is whether the right hemisphere is necessarily involved in metaphor comprehension.About this two questions,different studies produced very different results.Those contradictory results may be due to a confusion between different types of metaphors.Following this argument,the present study proposed that metaphors can be divided into two different categories,which are called derived metaphors and evoked metaphors,respectively.We examine cognitive processes and neural mechanisms of processing derived metaphors and evoked metaphors and literal expressions.The stimuli materials were two-words expressions consisting of literal semantic relations,evoked metaphor or derived metaphor.Participants were asked to judge the semantic relation between the two words.Experiment 1 using traditional cognitive behavioral methods to investigate processing differences between metaphor and literal.Experiment 2 using traditional cognitive behavioral methods to verify whether the right hemisphere is necessarily involved in metaphor comprehension.Experiment 3 using ERP methods to clarify this two hot issues.In conclusion:(1)The results support the parallel hypothesis of metaphor comprehension,we conclude that metaphors may share the same mechanism with literal ones,but evoked metaphors comprehension need more cognitive resources.In the semantic integration stage,the evoked metaphors processing is more complicated.(2)The results contrary to the right hemisphere theory of metaphor.Metaphorical nature and processing stages may determine whether the right hemisphere involved in metaphor comprehension and the degree of its involvement.In the early stages,evoked metaphor elicited more negative amplitudes than literal expressions in the right hemisphere,however,there was no significant difference between three materials at the late stages.