Letters persistence after physical offset: Visual word form area and left planum temporale. An fMRI study. Issue 6 (16th January 2012)

• Record Type: Journal Article
• Authors: Barban, Francesco; Daniele Zannino, Gian; Macaluso, Emiliano; Caltagirone, Carlo; Carlesimo, Giovanni A.
• Is Part Of: Human brain mapping. Volume 34:Issue 6(2013:Jun.)
• Page Start: 1282
• Page End: 1292
• Publication Date: 2012-01-16
• Subjects: fMRI -- iconic memory -- partial report -- visual perception -- consciousness; Brain mapping -- Periodicals; 611.81
• DOI: 10.1002/hbm.21509
• Languages: English
• ISSNs: 1065-9471

Abstract

Abstract: Iconic memory is a high‐capacity low‐duration visual memory store that allows the persistence of a visual stimulus after its offset. The categorical nature of this store has been extensively debated. This study provides functional magnetic resonance imaging evidence for brain regions underlying the persistence of postcategorical representations of visual stimuli. In a partial report paradigm, subjects matched a cued row of a 3 × 3 array of letters (postcategorical stimuli) or false fonts (precategorical stimuli) with a subsequent triplet of stimuli. The cued row was indicated by two visual flankers presented at the onset (physical stimulus readout) or after the offset of the array (iconic memory readout). The left planum temporale showed a greater modulation of the source of readout (iconic memory vs. physical stimulus) when letters were presented compared to false fonts. This is a multimodal brain region responsible for matching incoming acoustic and visual patterns with acoustic pattern templates. These findings suggest that letters persist after their physical offset in an abstract postcategorical representation. A targeted region of interest analysis revealed a similar pattern of activation in the Visual Word Form Area. These results suggest that multiple higher‐order visual areas mediate iconic memory for postcategorical stimuli. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.