Williams Leanne M, Felmingham Kim, Kemp Andrew H, Rennie Chris, Brown Kerri J, Bryant Richard A, Gordon Evian
The Brain Dynamics Centre, Westmead Millennium Institute & Western Clinical School, University of Sydney, Westmead Hospital, New South Wales, Sydney, Australia.
Neuroreport. 2007 Feb 12;18(3):197-202. doi: 10.1097/WNR.0b013e328010ff80.
Orienting responses are elicited by salient stimuli, and may be indexed by skin conductance responses. Concurrent functional magnetic resonance imaging and skin conductance response recording was used to identify neural correlates of orienting to abrupt sensory change (infrequent high pitch oddball 'target' tones embedded in frequent lower pitch 'standard' tones) in 16 healthy participants. 'With skin conductance response' responses to targets were distinguished by preferentially greater activity in the amygdala and ventral medial and lateral frontal cortical regions. By contrast, 'without skin conductance response' responses elicited distinctive activity in the dorsal lateral frontal cortex and supramarginal gyrus. These findings suggest that orienting to unexpected sensory change elicits a network for appraising salience and novelty, whereas, in the absence of orienting, a parallel network for sensory and context evaluation is preferentially engaged.
朝向反应由显著刺激引发,可通过皮肤电导率反应进行测量。对16名健康参与者采用功能磁共振成像和皮肤电导率反应同步记录的方法,以识别对突然的感觉变化(频繁出现的低音调“标准”音调中偶尔出现的高音调“目标”音调)产生朝向反应的神经关联。“伴有皮肤电导率反应”的对目标的反应,其特征在于杏仁核以及腹内侧和外侧额叶皮质区域有优先增强的活动。相比之下,“无皮肤电导率反应”的反应在背外侧额叶皮质和缘上回引发了独特的活动。这些发现表明,对意外感觉变化的朝向反应会引发一个用于评估显著性和新颖性的神经网络,而在没有朝向反应的情况下,则优先启用一个用于感觉和情境评估的并行网络。