Abstract
Does the perception of the end-product of an action reflect the temporal sequence of the action that produced it? Human actions have distinct temporal signatures. Letter writing is a particularly prevalent form of motor action involving the production of character strokes in an invariant sequence with a common temporal order. We have previously demonstrated that the temporal order of letter strokes primes letter recognition (Parkinson & Khurana. 2007, QJEP 60(9), 1265–1274): If letters are presented dynamically as an additive sequence of constituent strokes, letter/non-letter judgments are speeded when the temporal order of the strokes is consistent with that used in writing action. This stroke order priming effect is evidence for an influence of learned writing action upon ongoing visual perception of letters. Here we present direct evidence for the influence of the action-consistent temporal sequences on letter perception. We investigated the neural correlates of the stroke order priming effect by measuring event-related potentials (ERPs) associated with early visual processing, both when engaging in speeded letter/non-letter judgments and passively viewing identical stimuli. In accord with the behavioural results, we found that visual processing was speeded for letters that were produced by action-consistent stroke sequences, measured as significant latency shifts in early visual ERP components. Moreover, visual processing was speeded in the action-consistent sequence even prior to it becoming a letter or non-letter, implying that the action-consistent stroke sequence produces a visual prediction for letters before the onset of the letter stimulus. These effects are independent of the letter-judgment task, suggesting that the effect is not a form of response priming. Thus, if the dynamic sequence resembles the actions used to produce a letter, perceptual prediction and speeded visual processing occur for the final stimulus. This is further evidence for an action-perception link for common motor behaviours such as writing.