Accessing orthographic representations from speech: the role of left ventral occipitotemporal cortex in spelling.
Bottom Line: Such an orthographic word lexicon is posited by cognitive dual-route theories of reading and spelling.In the scanner, participants performed a spelling task in which they had to indicate if a visually presented letter is present in the written form of an auditorily presented word.Our results suggest that activation of left vOT during spelling can be attributed to the retrieval of orthographic whole-word representations and, thus, support the position that the left vOT potentially represents the neuronal equivalent of the cognitive orthographic word lexicon.
Affiliation: Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria.Show MeSH
Related in: MedlinePlus
Mentions: The experimental conditions were presented in six blocks of five trials. Each block started with an instruction screen (1,500 ms) that indicated the task (i.e., spelling or gender decision) and informed about the stimulus type (i.e., words or pseudowords). The individual trials of all conditions began with a fixation cross that was presented centrally on the screen for 1,500 ms. During this time interval, a signal tone (200 ms) followed by an auditory word or pseudoword were presented via headphones. The length of the auditory words/pseudowords ranged from 534 to 1,068 ms (M = 757 ms). The end of the auditory stimuli was aligned to the end of the fixation period. After the auditory stimuli a lower-case letter was presented centrally on the screen for 500 ms. Trials ended with a 2,500 ms response interval during which a fixation cross was presented. The sequence of events in a trial is illustrated in Figure 1. The total length of a trial was 4 s resulting in a total block length of 21.5 s. Throughout each block, visual task reminders were present centrally in the upper half of the display: a tick for the spelling probe task and the Venus symbol for the gender decision control task. The number of “yes” responses for the five trials per block varied from one to four. The experimental design also included six rest blocks (fixation periods) of the same length as the task blocks. All blocks were presented within a single run. The order of block presentation was optimized using a genetic algorithm [Wager and Nichols, 2003]. When a task block was not followed by a rest block, a short fixation period of 3,000 ms was inserted between task blocks. The total length of the experiment was approximately 14 min.
Affiliation: Centre for Cognitive Neuroscience, University of Salzburg, Salzburg, Austria.