tailieunhanh - .Neuroscience of Rule-Guided Behavior Phần 3

Các nghiên cứu khác cũng lôi kéo APF trong các đại diện của các quy tắc nhiệm vụ cao hơn. Ví dụ, Bunge et al. Điều chỉnh linh hoạt được thúc đẩy bởi những kinh nghiệm trong quá khứ, mục tiêu hiện tại, và các yếu tố môi trường. | 76 Rule Representation Phonological judgment Figure 4-6 Schematic drawing of the neural mechanisms of task preparation left target word processing middle and task processing right . Task set activity in the anterior prefrontal cortex APF establishes the pattern of inter-regional interaction specific to the task to be performed. The incoming information from a visually presented target word influences the activity in the fusiform gyrus FG and then in the premotor cortex PM and anterior part of the inferior frontal gyrus aIFG in the same manner across the tasks. Due to the pre-established task set pattern the processing of the word occurs in areas associated with the task specified by the instruction. Other studies also implicate the APF in the representation of higher-order task rules. For example Bunge et al. 2003 have shown that the activity in the APF is significantly higher during the delay when participants prepare to perform a non-Match task than when they perform a Match or simple sensorimotor association task. In this study the participants reported that they conceptualized a non-Match task as the reverse of a Match task and the activity in the APF was believed to reflect elaboration of a default rule. In other studies the APF was shown to be especially active when participants switched between two tasks based on different rules than when they performed a single task Braver et al. 2003 and when participants need to activate delayed intentions to perform a secondary task during performance of another task Koechlin et al. 1999 Burgess et al. 2003 Badre and Wagner 2004 . The APF is also involved in guidance of memory control mechanisms Lepage et al. 2000 Otten et al. 2006 . Otten et al. 2006 used an electroencephalogram while participants performed an incidental encoding of words and they found that the activity in the APF before the word presentation differed depending on whether the word was subsequently remembered. Importantly the participants were not .