A pilot study of the reading processes combining reading-related potentials (RRPs) and fMRI

Aim of this work is to describe temporally and spatially the activation of the cerebral areas involved in reading processes by combining fMRI and reading-related potentials (RRPs). RRPs and fMR images were recorded in separate studies during a specifically designed experimental procedure. The protocol consisted of three visual tasks of increasing complexity. In the first two tasks subjects were asked to passively watch at letters and symbols respectively without making any effort in reading or articulating silently them. In the third task subjects were asked to read aloud letters appearing on a screen at a rate of 0.5 Hz. 7 young healthy subjects participated in the experiment. The analysis of RRPs highlighted the following results. During non-alphabetic symbols presentation the amplitude of the potentials was lower in comparison to presentation of letters. Reading aloud generated RRPs of greater amplitude than implicit reading. The analysis of fMRI scans revealed that the visual presentation of both letters and symbols produced similar activation of primary visual areas. Besides these areas, reading aloud activated the motor and pre-motor cortices and the left anterior temporal lobe. The combined analysis of RRPs and fMRI characterizes both temporally and spatially the development of reading processes.