a Centre de recherche, Institut universitaire de gériatrie de Montréal & Faculté de médecine, Université de Montréal, Montréal, Canada.
Neuropsychol Dev Cogn B Aging Neuropsychol Cogn. 2011 Jul;18(4):452-70. doi: 10.1080/13825585.2011.568047.
The possibility that the HAROLD phenomenon (i.e., Hemispheric Asymmetry Reduction in OLDer adults) is manifested in the course of access to semantic information, in particular the meaning of emotional words, was investigated using the visual half-field priming paradigm. The time course of priming was tracked in the cerebral hemispheres across three SOAs: 150, 300, and 750 ms. The results showed older and young adults had the same level of accuracy. While priming occurred unilaterally in young participants, the pattern of priming in older participants appeared to be bilateral whenever it was present, that is, at the 300- and 750-ms SOAs. The delay in the appearance of priming in older adults may be due to an increase in sensory thresholds that causes older adults to need more time to encode stimuli and fully activate their semantic network. It is concluded that the bilateral pattern of priming in the presence of an equivalent level of performance in older adults provides behavioral evidence supporting the compensatory role of the HAROLD phenomenon for this particular task.
该研究采用视觉半视野启动范式，探讨了 HAROLD 现象（即老年人大脑两半球不对称性降低）是否表现在语义信息，尤其是情绪词的意义获取过程中。实验追踪了三个 SOA（150、300 和 750 毫秒）条件下大脑两半球的启动时程。结果表明，老年人和年轻人的准确率相同。年轻参与者的启动呈单侧性，而老年人的启动模式无论是否存在（即 300 和 750 毫秒 SOA 条件下），均呈双侧性。老年人启动延迟可能是由于感觉阈值增加，导致老年人需要更多时间来编码刺激并充分激活他们的语义网络。结论认为，老年人在表现出同等水平的任务绩效时呈现出双侧启动模式，为 HAROLD 现象在特定任务中的补偿作用提供了行为证据。
