Only few studies on the development of oculomotor functions after the age of 6 - 7 y have been published so far. Recently, Fischer et al. (1997) reported augmented error rates and response latencies of children aged 6 to 15 y in the antisaccade task. The present study aimed at replicating and extending these results.

Three sex- and IQ-matched age groups (6 - 7, 10 - 11, and 18 - 26 y) of 17, 18, and 20 participants, respectively, were tested on two successive days. On day/session 1, horizontal pro- and antisaccades under the 200 ms gap and overlap conditions were measured. On day/session 2, a horizontal and a vertical antitask as well as a nogo condition were presented. Eye movements were measured binocularly with the IRIS infrared device (SKALAR, Delft, NL). Each of the task blocks comprised 100 trials (50 targets at either side in random order).

Adult and 10 - 11 year old participants exhibited faster saccadic reaction times (most pronounced during the antitask), less antitask direction errors, less anticipatory eye movements, and less go responses during the nogo fixation condition than 6 - 7 year old children. Adults differed from 10 - 11 year old children in showing reduced saccadic reaction times and proportions of errors during the antitask. Both children groups made more express saccades during the protasks than the older participants.

Our results suggest different degrees of improvement with increasing age for the oculomotor functions assessed in this experiment, these effects being greatest for the proficiency to inhibit reflexive prosaccades during the antitask. These results are consistent with the assumption of protracted development of prefrontal cortical functions.

Research was supported by the Deutsche Forschungsgemeinschaft (DFG; Kl 985/6-1).