The most commonly used method for formally assessing grapheme-colour synaesthesia (i.e., experiencing colours in response to letter and/or number stimuli) involves selecting colours from a large colour palette on several occasions and measuring consistency of the colours selected. However, the ability to diagnose synaesthesia using this method depends on several factors that have not been direc...

People with synaesthesia have been reported to show atypical electrophysiological responses certain simple sensory stimuli, even if these stimuli are not inducers of synaesthesia. However, it is unclear whether this constitutes a neural marker that relatively specific or reflects some other trait co-occurs synaesthesia, but it. One candidate sensitivity (e.g., strong aversion lights and sounds,...

The present study investigates the consistency of synaesthetic attribution. By means of a local press campaign we recruited 50 participants reporting synaesthesia. Of those, 19 reported mainly lexical synaesthesia, and 11 reported occasional lexical synaesthesia besides other synaesthetic experiences. By comparing repeated colour selection (RGB-colour space) attributed to alphanumeric signs (vo...

INTRODUCTION Over the last century, researchers and laypeople alike have been captivated by synaesthesia—a developmental condition present in approximately 5% of the adult population, where the presentation of an “inducer” stimulus gives rise to additional “concurrent” sensation absent from the veridical sensory world (Ward, 2013). For example, the most common variant is grapheme-color synaesth...

Synaesthesia has been described as a perceptual phenomenon that creates a 'merging of senses'. Therefore, academic treatments have focused primarily on its sensory characteristics and similarities with veridical perception. This approach has dominated, despite parallel work that has suggested conceptual influences are involved, including data that show a large number of synaesthetic variants ar...

Gould et al. (2014) refreshingly devote an entire paper to investigating the detailed experience of a synaesthete (AB), using a rigorous qualitative method. Their paper addresses sequence-space synaesthesia, in which people associate members of sequences such as months or numbers with specific spatial locations that together create an overall spatial pattern or “form” for each sequence. I have ...

Synaesthesia is a rare condition in which stimulation in one modality leads to a secondary experience in another sensory modality. Varying accounts attribute the condition to either neuroanatomical differences between the synaesthetes and nonsynaesthetes or functional differences in how sensory brain regions interact. This study employed voxel-based-morphometry to examine whether synaesthetes w...

In spatial sequence synaesthesia (SSS) ordinal stimuli are perceived as arranged in peripersonal space. Using fMRI, we examined the neural bases of SSS and colour synaesthesia for spoken words in a late-blind synaesthete, JF. He reported days of the week and months of the year as both coloured and spatially ordered in peripersonal space; parts of the days and festivities of the year were spatia...