Department of Clinical Psychology and Psychobiology, Faculty of Psychology, University of Santiago de Compostela, Spain.
Biol Psychol. 2012 Oct;91(2):201-11. doi: 10.1016/j.biopsycho.2012.06.004. Epub 2012 Jun 26.
It is still not well known whether the age-related behavioural slowing observed during visual search is due to changes in the allocation of attention, in response activation patterns, or to a combination of both. To help in clarifying it, attention-related (N2 posterior contralateral; N2pc, and N2 central contralateral; N2cc) and response-related (Motor Potential; MP, and Reafferent Potential; RAP) event-related potentials (ERPs) were obtained in healthy young and older participants executing a visual search task. Age was associated with N2pc and N2cc longer latencies, earlier MP onsets and longer MP rise times. Lower N2pc, higher MP and lower RAP amplitudes were also observed. Results suggest that older participants need more time to allocate spatial attention onto the target (N2pc) and to prevent cross talk between response selection and attention direction (N2cc), and that they are slower and need higher cortical activation when preparing and executing correctly selected responses (MP).
目前尚不清楚在视觉搜索过程中观察到的与年龄相关的行为减速是由于注意力分配的变化、反应激活模式的变化还是两者的结合。为了帮助澄清这一点，在健康的年轻和年长参与者执行视觉搜索任务时，获得了与注意力相关的（N2 对侧后部；N2pc 和 N2 中央对侧；N2cc）和与反应相关的（运动电位；MP 和再传入电位；RAP）事件相关电位（ERP）。年龄与 N2pc 和 N2cc 潜伏期延长、MP 起始较早和 MP 上升时间较长有关。还观察到较低的 N2pc、较高的 MP 和较低的 RAP 振幅。结果表明，年长参与者需要更多的时间将空间注意力分配到目标上（N2pc），并防止反应选择和注意力方向之间的串扰（N2cc），并且当准备和正确执行选择的反应时，他们的速度较慢，需要更高的皮质激活（MP）。
