Ludwig-Maximilians-Universität München, Munich, Germany.
J Cogn Neurosci. 2023 Jul 1;35(7):1075-1091. doi: 10.1162/jocn_a_02002.
Flexible changes in behavior can involve changes in the processing of external information (i.e., shifts in attention between different stimuli) or internal information (i.e., shifts in task rules stored in memory). However, it is unclear if different types of flexible change rely on separate, domain-specific neural processes or on a domain-general system, which enables flexible actions independent of the type of change needed. In the current study, participants performed a task switching procedure while we measured neural oscillations via EEG. Importantly, we independently manipulated the need to switch attention between 2 types of stimuli, as well as the need to switch between two sets of stimuli-response rules stored in memory. Both attentional and rule switches significantly increased error rates and RTs. On a neural level, both types of changes were associated with a widespread decrease in alpha power, predominantly over the parietal cortex. Attentional switches and rule switches showed a subadditive interaction effect on both participants' performance as well as on their alpha power reactivity. This indicates that implementing both changes at the same time was more efficient than implementing each individual change separately. Independent of the presence or absence of either attentional or rule switches, higher frontal theta power and lower parietal/posterior alpha power predicted faster responses on correct trials. Our study suggests that flexible behavior relies on domain-general frontal and parietal oscillatory dynamics, which enable efficient implementation of goal-directed actions independent of which aspects of the task change.
行为的灵活变化可能涉及外部信息处理的变化(即注意力在不同刺激之间的转移)或内部信息处理的变化(即存储在记忆中的任务规则的转移)。然而,目前尚不清楚不同类型的灵活变化是依赖于独立的、特定于领域的神经过程,还是依赖于一个通用的、能够使动作灵活变化而不受所需变化类型影响的系统。在当前的研究中,参与者在执行任务转换程序的同时,我们通过 EEG 测量了神经振荡。重要的是,我们独立地操纵了在两种类型的刺激之间转换注意力的需求,以及在存储在记忆中的两组刺激-反应规则之间转换的需求。注意力和规则的转换都显著增加了错误率和 RT。在神经水平上,这两种类型的变化都与广泛的 alpha 功率下降有关,主要是在顶叶皮层。注意力转换和规则转换在参与者的表现和他们的 alpha 功率反应性上都表现出亚加性的相互作用效应。这表明同时执行这两种变化比分别执行每一种变化更有效率。无论是否存在注意力或规则转换,更高的额部 theta 功率和更低的顶叶/后部 alpha 功率预示着在正确试次上更快的反应。我们的研究表明,灵活的行为依赖于通用的额部和顶叶振荡动力学,它能够使目标导向的动作高效执行,而不受任务变化的哪些方面的影响。