How metaphors influence semantic relatedness judgments: the role of the right frontal cortex.
We used event-related fMRI (ER-fMRI) to test the hypothesis that metaphors bias cognitive processing of semantic relatedness towards a search for a wider range of associations. Twelve right-handed male volunteers read a mixture of metaphoric and literal sentences, each sentence being followed by a single word, which could be semantically related or not to the preceding sentence context. We found that judging unrelated words as contextually irrelevant was associated with increased blood oxygenation level-dependent (BOLD) signal in the right ventrolateral prefrontal cortex in the metaphoric but not in the literal condition. The same region was also activated when subjects endorsed a semantic relation between words and metaphoric sentence primes but not between words and literal sentence primes. We argue that these results are consistent with the notion of semantic open-endedness, whereby figurative statements bias cognitive processing towards a search for a wider range of semantic relationships compared to literal statements, and thus lend further support to the view that coarse semantic coding occurs preferentially in the right hemisphere.
Stringaris
Argyris K
AK
Section of Cognitive Neuropsychiatry, Institute of Psychiatry at the Maudsley, King's College London, PO 68 Denmark Hill, London SE5 8AF, UK. a.stringaris@iop.kcl.ac.uk
Medford
Nicholas
N
Giora
Rachel
R
Giampietro
Vincent C
VC
Brammer
Michael J
MJ
David
Anthony S
AS
D001931:Brain Mapping; D016000:Cluster Analysis; D005625:Frontal Lobe / Q000502:physiology*; D007839:Functional Laterality; D006801:Humans; D007600:Judgment; D007802:Language; D008279:Magnetic Resonance Imaging; D008297:Male; D019365:Metaphor; D011930:Reaction Time; D012660:Semantics; D013060:Speech