Insights from introspection: A commentary on Gould et al. (2014), “An extended case study on the phenomenology of spatial form synaesthesia.”

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 previously argued that sequence-space synaesthesia shows strong continuity with normal voluntary visuospatial imagery (Price, 2009; 2013), and may be an extension of normal childhood development of visuospatial skills (Price and Pearson, 2013). Additionally I have suggested that behavioural evidence for the automaticity of this synaesthesia is less robust than often claimed (Price and Mattingley, 2013). Gould et al.’s data provide striking support for these claims. Take continuity with normal visuospatial imagery: 1. Some spatial forms seem indistinguishable from normal imagery: e.g. AB’s multiple and dynamic ‘spatial forms’ for clock-time constitute a vivid visual imagery of clocks that would unlikely be considered synaesthetic if reported by a non-synaesthete. 2. Spatial relationships of sequence items are only a subset of AB’s total visualisation experience: e.g. Equations and graphs are visualised together with numerals on his number line; scenes of embryonic development are associated with his autobiographical timeline; his alphabet form resides within the dark, muddy atmosphere of a cave, itself part of an expansive landscape. 3. Imagery when attending single sequence items is similar to normal alphanumeric imagery: e.g. Individual numerals/letters are often imaged in isolation from the rest of AB’s number or alphabet form, and although these images contain salient colour, texture and font, they do not seem so far removed from non-synaesthetic ability to visualise graphemes. 4. Like normal imagery, aspects of the synaesthetic imagery can be somewhat modulated voluntarily: e.g. AB can effortfully but unstably modify the font of single letters or numerals in a form. 5. Like normal visual imagery, spatial forms can be mentally scanned: e.g. AB appears to intentionally shift attention from one sequence member to another, progressively reconstructing his spatial form by activating long term memory of the relative locations of sequence members. Next consider how voluntary attention mediates AB’s experiences: 1. Attentional movement is required to activate parts of AB’s number line that were not previously in focus. 2. Focal attention increases stability of AB’s