Fischer B, Biscaldi M, Gezeck S
Brain Research Unit, Institute of Biophysics, University of Freiburg, Germany.
Brain Res. 1997 Apr 18;754(1-2):285-97. doi: 10.1016/s0006-8993(97)00094-2.
The saccadic performance of a large number (n = 281) of subjects of different ages (8-70 years) was studied applying two saccade tasks: the prosaccade overlap (PO) task and the antisaccade gap (AG) task. From the PO task, the mean reaction times and the percentage of express saccades were determined for each subject. From the AG task, the mean reaction time of the correct antisaccades and of the erratic prosaccades were measured. In addition, we determined the error rate and the mean correction time, i.e. the time between the end of the first erratic prosaccade and the following corrective antisaccade. These variables were measured separately for stimuli presented (in random order) at the right or left side. While strong correlations were seen between variables for the right and left sides, considerable side asymmetries were obtained from many subjects. A factor analysis revealed that the seven variables (six eye movement variables plus age) were mainly determined by only two factors, V and F. The V factor was dominated by the variables from the AG task (reaction time, correction time, error rate) the F factor by variables from the PO task (reaction time, percentage express saccades) and the reaction time of the errors (prosaccades!) from the AG task. The relationship between the percentage number of express saccades and the percentage number of errors was completely asymmetric: high numbers of express saccades were accompanied by high numbers of errors but not vice versa. Only the variables in the V factor covaried with age. A fast decrease of the antisaccade reaction time (by 50 ms), of the correction times (by 70 ms) and of the error rate (from 60 to 22%) was observed between age 9 and 15 years, followed by a further period of slower decrease until age 25 years. The mean time a subject needed to reach the side opposite to the stimulus as required by the antisaccade task decreased from approximately 350 to 250 ms until age 15 years and decreased further by 20 ms before it increased again to approximately 280 ms. At higher ages, there was a slight indication for a return development. Subjects with high error rates had long antisaccade latencies and needed a long time to reach the opposite side on error trials. The variables obtained from the PO task varied also significantly with age but by smaller amounts. The results are discussed in relation to the subsystems controlling saccade generation: a voluntary and a reflex component the latter being suppressed by active fixation. Both systems seem to develop differentially. The data offer a detailed baseline for clinical studies using the pro- and antisaccade tasks as an indication of functional impairments, circumscribed brain lesions, neurological and psychiatric diseases and cognitive deficits.
前扫视重叠（PO）任务和反扫视间隙（AG）任务，对大量不同年龄（8 - 70岁）的受试者（n = 281）的扫视表现进行了研究。从前扫视重叠任务中，确定了每个受试者的平均反应时间和快速扫视的百分比。从反扫视间隙任务中，测量了正确反扫视和不稳定前扫视的平均反应时间。此外，我们还确定了错误率和平均校正时间，即第一次不稳定前扫视结束到随后的校正反扫视之间的时间。这些变量针对在右侧或左侧（以随机顺序呈现）的刺激分别进行测量。虽然右侧和左侧变量之间存在很强的相关性，但许多受试者存在相当大的侧不对称性。因子分析表明，七个变量（六个眼动变量加年龄）主要仅由两个因子，即V和F决定。V因子主要由反扫视间隙任务的变量（反应时间、校正时间、错误率）主导，F因子由前扫视重叠任务的变量（反应时间、快速扫视百分比）以及反扫视间隙任务中错误（前扫视！）的反应时间主导。快速扫视百分比与错误百分比之间的关系完全不对称：高快速扫视数量伴随着高错误数量，但反之不然。只有V因子中的变量与年龄共变。在9岁至15岁之间，观察到反扫视反应时间（减少50毫秒）、校正时间（减少70毫秒）和错误率（从60%降至22%）快速下降，随后在25岁之前有一段下降较慢的时期。根据反扫视任务要求，受试者到达与刺激相反一侧所需的平均时间在15岁之前从约350毫秒降至250毫秒，并在再次增加到约280毫秒之前进一步减少20毫秒。在较高年龄时，有轻微的迹象表明出现了回归发展。错误率高的受试者反扫视潜伏期长，在错误试验中到达相反一侧需要很长时间。从前扫视重叠任务中获得的变量也随年龄有显著变化，但变化量较小。结合控制扫视产生的子系统对结果进行了讨论：一个是自主成分，另一个是反射成分，后者在主动注视时受到抑制。这两个系统似乎有不同的发展。这些数据为使用前扫视和反扫视任务作为功能损伤、局限性脑损伤、神经和精神疾病以及认知缺陷指标的临床研究提供了详细的基线。
