Department of Psychology, City of London Polytechnic, Old Castle St., London E1 7NT, UK.
J Psychopharmacol. 1992 Jan;6(3):352-6. doi: 10.1177/026988119200600302.
Chronic exposure to very mild unpredictable stress has previously been found to reduce or abolish the acquisition of place preference conditioning. In the present study, chronic mild stress was found to abolish the acquisition of preferences for a distinctive environment paired with morphine (0.7 mg/kg). However, chronic mild stress did not impair the acquisition of place aversion conditioning induced by naloxone (0.7 mg/kg) or picrotoxin (2.0 mg/kg). The results demonstrate that chronic stress does not cause a general impairment of associative learning but, rather, a specific impairment of rewarded behaviour.
先前的研究发现，慢性暴露于非常轻微的不可预测的应激下，会减少或消除位置偏好条件形成。在本研究中，慢性轻度应激被发现会消除与吗啡（0.7mg/kg）配对的独特环境偏好的获得。然而，慢性轻度应激并不损害纳洛酮（0.7mg/kg）或苦毒蕈碱（2.0mg/kg）诱导的位置厌恶条件形成的获得。结果表明，慢性应激不会导致联想学习的普遍损伤，而是导致奖励行为的特异性损伤。
