Glick S D, Weaver L M, Meibach R C
Psychopharmacology (Berl). 1981;73(4):323-7. doi: 10.1007/BF00426459.
Rats with bilaterally implanted lateral hypothalamic electrodes were tested daily for self-stimulation to each side of the brain; rotation (circling behavior) was recorded concomitantly. All rats rotated in a perferred direction regardless of the side of the brain stimulated and all rats had asymmetries in self-stimulation sensitivity (threshold and rate-intensity functions) related to the direction of rotation. Amphetamine both enhanced rotation and potentiated the asymmetry in self-stimulation sensitivity. Subsequently rats were tested in a choice procedure providing concurrent access to rewarding stimulation of either side of the brain; currents were titrated such that, under baseline conditions, rats continually alternated between self-stimulating one side of the brain or the other. Amphetamine induced a robust preference for stimulation to the more sensitive side of the brain (the side having a lower threshold). The results are discussed in relation to mechanisms of drug reinforcement and to biological etiologies of schizophrenia. It is proposed that schizophrenia results from a lateralized overactivity of dopaminergic neuronal systems mediating reward and that amphetamine mimics schizophrenic symptomatology by enhancing lateralization of the same systems.
对双侧植入下丘脑外侧电极的大鼠每天进行测试，以检测其对脑两侧的自我刺激情况；同时记录旋转（转圈行为）。所有大鼠无论刺激脑的哪一侧，均沿偏好方向旋转，且所有大鼠在与旋转方向相关的自我刺激敏感性（阈值和频率-强度函数）上存在不对称性。苯丙胺既增强了旋转，又增强了自我刺激敏感性的不对称性。随后，让大鼠在一种选择程序中接受测试，该程序能让大鼠同时获得对脑两侧奖励性刺激的机会；对电流进行调整，使得在基线条件下，大鼠在自我刺激脑的一侧和另一侧之间持续交替。苯丙胺引发了对脑更敏感一侧（阈值较低的一侧）刺激的强烈偏好。结合药物强化机制和精神分裂症的生物学病因对结果进行了讨论。有人提出，精神分裂症是由介导奖励的多巴胺能神经元系统的偏侧化过度活动导致的，而苯丙胺通过增强同一系统的偏侧化来模拟精神分裂症的症状学表现。
