Talk Andrew, Stoll Elizabeth, Gabriel Michael
Department of Psychology, University of Illinois at Urbana-Champaign, IL, USA.
Behav Neurosci. 2005 Dec;119(6):1524-32. doi: 10.1037/0735-7044.119.6.1524.
Neuronal activity of the auditory thalamus, amygdala, cingulate cortex, and substantia nigra was recorded during the administration of a behavioral test for latent inhibition (LI) or the retardation of behavioral conditioning because of preexposure of the conditional stimulus (CS). Following CS preexposure, both the preexposed CS and a control CS predicted avoidable footshock. LI occurred as significantly fewer avoidance conditioned avoidance responses after the preexposed CS than after the control CS. Attenuation of neuronal responses to the preexposed CS, or neural LI, occurred in all monitored areas. One group of subjects (Oryctolagus cuniculus) then received context extinction, and additional groups experienced novel context exposure or handling. Context extinction enhanced behavioral responding to the preexposed CS, eliminating LI. Context extinction also eliminated cingulate cortical neural LI by enhancing posterior cingulate cortical responses to the preexposed CS and attenuating anterior cingulate cortical responses to the control CS. Present and past results are interpreted to indicate that LI is (a) a failure of response retrieval and/or expression mediated by interfering CS-context associations and (b) a product of interactions of the posterior cingulate cortex and the hippocampus.
在进行潜在抑制（LI）行为测试或由于条件刺激（CS）预暴露导致行为条件反射延迟时，记录了听觉丘脑、杏仁核、扣带回皮质和黑质的神经元活动。在CS预暴露后，预暴露的CS和对照CS都预示着可避免的足部电击。LI表现为预暴露的CS后产生的回避条件回避反应明显少于对照CS后产生的反应。在所有监测区域都出现了对预暴露CS的神经元反应减弱，即神经LI。然后，一组受试者（穴兔）接受情境消退，其他组经历新情境暴露或处理。情境消退增强了对预暴露CS的行为反应，消除了LI。情境消退还通过增强后扣带回皮质对预暴露CS的反应并减弱前扣带回皮质对对照CS的反应，消除了扣带回皮质的神经LI。当前和过去的结果被解释为表明LI是（a）由干扰性CS-情境关联介导的反应检索和/或表达失败，以及（b）后扣带回皮质和海马体相互作用的产物。
