Beyond the leftward limit of the perceptual span: Parafoveal processing to the left of fixation in Chinese reading.

During reading, Chinese readers have been found to obtain useful visual information from one character to the left to three characters to the right of fixation. The perceptual span is asymmetrical, and its leftward extent seems to be limited compared with the rightward extent. We conducted an experiment to investigate whether Chinese readers could process written information beyond the leftward extent of the perceptual span. We did this by using a variation of the gaze-contingent display change paradigm (Rayner, Cognitive Psychology, 81, 65-81, 1975) in order to manipulate the parafoveal "postview" that was available to the left of where readers were fixating. Each sentence contained an invisible boundary. Once the readers' eyes crossed the boundary, all of the characters to the left of the boundary except for one, two, or three characters directly to the left of the boundary were replaced with visually similar characters. The change lasted for only one single fixation, resulting in four different "postview" conditions including a control condition (n - 1, n - 2, n - 3, control). The results showed that, compared with the control condition, there were more regressions to the display change area immediately after readers' eyes crossed the boundary in the n - 1, n - 2, and n - 3 conditions, demonstrating that readers can acquire information from the three characters to the left of fixation at least

Cerebellar Structures and the Programming of Movement Sequences

Two patients with unilateral damage to the medial and lateral cerebellum were examined to determine whether local structures in the cerebellum are used to execute programmed movement sequences. Both patients performed a sequential tapping task which required the execution of either a single keystroke or of a sequence of three keystrokes. Movements executed with the contralateral hand showed increases in response onset times as the movement sequence increased from one to three response elements (sequence length effect). Furthermore, noninitial response elements were executed considerably faster than sequence initial responses (position effect). Movements executed with the ipsilateral hand showed a different pattern of results. Damage to medial cerebellar structure had no qualifying effect but damage to the lateral cerebellar structure eliminated effects of sequence length and of response position. The results suggest that the lateral cerebellum is implicated in the execution of programmed manual movement sequences