We investigated grapheme-colour synaesthesia and found that The induced colours led to perceptual grouping and pop-out, a number rendered invisible through 'crowding' or lateral masking can induce synaesthetic colours -- a form of blindsight -- and peripherally presented graphemes did not induce colours even when they were clearly visible. Taken collectively, these and other experiments prove conclusively that synaesthesia is a genuine perceptual phenomenon, not an effect based on memory associations from childhood or on vague metaphorical speech. We identify different (...) subtypes of number-colour synaesthesia and propose that they are caused by hyperconnectivity between colour and number areas at different stages in processing; lower synaesthetes may have cross-wiring within the fusiform gyrus whereas higher synaesthetes may have cross-activation in the angular gyrus. This hyperconnectivity might be caused by a genetic mutation that causes defective pruning of connections between brain maps. The mutation may further be expressed selectively in the fusiform or angular gyri, and this may explain the existence of different forms of synaesthesia. If expressed very diffusely, there may be extensive cross-wiring between brain regions that represent abstract concepts, which would explain the link between creativity, metaphor and synaesthesia. Also, hyperconnectivity between the sensory cortex and amygdala would explain the heightened aversion synaesthetes experience when seeing numbers printed in the 'wrong' colour. Lastly, kindling -- induced hyperconnectivity in the temporal lobes of temporal lobe epilepsy patients -- may explain the purported higher incidence of synaesthesia in these patients. We conclude with a synaesthesia-based theory of the evolution of language. Thus, our experiments on synaesthesia and our theoretical framework attempt to link several seemingly unrelated facts about the human mind. Far from being a mere curiosity, synaesthesia may provide a window into perception, thought and language. (shrink)

Sound-symbolism is the nonarbitrary link between the sound and meaning of a word. Japanese-speaking children performed better in a verb generalization task when they were taught novel sound-symbolic verbs, created based on existing Japanese sound-symbolic words, than novel nonsound-symbolic verbs (Imai, Kita, Nagumo, & Okada, 2008). A question remained as to whether the Japanese children had picked up regularities in the Japanese sound-symbolic lexicon or were sensitive to universal sound-symbolism. The present study aimed to provide support for the latter. In (...) a verb generalization task, English-speaking 3-year-olds were taught novel sound-symbolic verbs, created based on Japanese sound-symbolism, or novel nonsound-symbolic verbs. English-speaking children performed better with the sound-symbolic verbs, just like Japanese-speaking children. We concluded that children are sensitive to universal sound-symbolism and can utilize it in word learning and generalization, regardless of their native language. (shrink)

Measuring event-related potentials (ERPs) has been fundamental to our understanding of how language is encoded in the brain. One particular ERP response, the N400 response, has been especially influential as an index of lexical and semantic processing. However, there remains a lack of consensus on the interpretation of this component. Resolving this issue has important consequences for neural models of language comprehension. Here we show that evidence bearing on where the N400 response is generated provides key insights into what it (...) reflects. A neuroanatomical model of semantic processing is used as a guide to interpret the pattern of activated regions in functional MRI, magnetoencephalography and intracranial recordings that are associated with contextual semantic manipulations that lead to N400 effects. (shrink)

This article presents empirical evidence of the high referential specificity of sound-symbolic words, based on a FrameNet-aided analysis of collocational data of Japanese mimetics. The definition of mimetics, particularly their semantic definition, has been crosslinguistically the most challenging problem in the literature, and different researchers have used different adjectives (most notably, “vivid,” since Doke 1935) to describe their semantic peculiarity. The present study approaches this longstanding issue from a frame-semantic point of view combined with a quantitative method. It was found (...) that mimetic manner adverbials generally form a frame-semantically restricted range of verbal/nominal collocations than non-mimetic ones. Each mimetic can thus be considered to evoke a highly specific frame, which elaborates the general frame evoked by its typical host predicate and contains a highly limited set of frame elements, which correlate and constrain one another. This conclusion serves as a unified account of previously reported phenomena concerning mimetics, including the lack of hyponymy, the one-mimetic-per-clause restriction, and unparaphrasability. This study can be also viewed as a methodological proposal for the measurement of frame specificity, which supplements bottom-up linguistic tests. (shrink)